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Anniversary Issue 1/2011

Porsche Engineering Magazine

80 years of engineering services.Time to look back?

Anniversary Issue 1/2011

Porsche Engineering Magazine

Sure, but not for too long.The future is waiting.

At Porsche Engineering, engineers areworking on your behalf to come up withnew and unusual ideas for vehicles andindustrial products. At the request ofour customers we develop a variety ofsolutions – ranging from the design ofindividual components and the layout ofcomplex modules to the planning andimplementation of complete vehicles,inclu ding production start-up manage -ment. What makes our services specialis that they are based on the expertise

About Porsche Engineering

4 Porsche Engineering Magazine 1/2011

EditorFrederic Damköhler

Design: Agentur Designwolf, Stuttgart Repro: Piltz Reproduktionen, StuttgartPrinting: Leibfarth&Schwarz, Dettingen/ErmsTranslation: TransMission Übersetzungen, Stuttgart

All rights reserved. No part of this publication may be reprodu-ced without the prior permission of the publisher. We cannotguarantee that unrequested photos, slides, videos or manus-cripts will be returned.

Porsche Engineering is a 100% subsidiary of Dr. Ing. h.c. F.Porsche AG.

PublisherPorsche Engineering Group GmbH

AddressPorsche Engineering Group GmbHPorschestraße71287 Weissach, Germany

Tel. +49 711 911 - 8 88 88Fax +49 711 911 - 8 89 99

E-mail: [email protected]: www.porsche-engineering.com

Impressum Porsche Engineering Magazine

of a premium car manufacturer. Whetheryou need an automotive developer foryour project or would prefer a specialistsystems developer, we offer both – be -cause Porsche Engineering works rightwhere these two areas meet. The exten -sive knowledge of Porsche Engi neeringconverges in Weissach – and yet it isglob ally available, including at your com -p any’s offices or production facili ties.Regardless of where we work, we alwaysbring a part of Porsche with us.

Impressum

Editorial

5

Intelligent thermal management also playsan important role in electromobility. Theengineers at Porsche Engineering havethus developed new technologies toachieve optimum temperatures usingonly the available battery capacity.

The increasing use of electricity topower vehicles is evident in numerousother areas of mobility, whether it isbattery-operated watersports equip mentor all-terrain hybrid mountain bikes. Thecurrent pinnacle of this development isthe Panamera S Hybrid, which marriesvehicle efficiency, sportiness and ele -gance like no other vehicle.

As you can see, our ideas reach far intothe future. We look forward to every newchallenge to master.

We hope you enjoy the anniversary issueof our magazine.

Yours, Malte Radmann and Dirk LappeManaging Directors Porsche Engineering

For more than 80 years, the name Porsche has stood

for engineering services with the highest standards of

quality and levels of innovation. We develop solutions

that help our customers to move forward and are always

dedicated to meeting the challenges of tomorrow.

Dear Readers,

Ferdinand Porsche was also always look -ing ahead: he developed the first func -tioning hybrid automobile in the worldway back in 1900. With the founding ofhis engineering office in 1931, FerdinandPorsche also made his creativity and hisengineering expertise available to exter -nal clients. We are honored to continuethis tradition.

Come with us on a journey through ourhistory and discover the milestones ofour customer projects. But let’s notremain in the past for too long, be causethe future is waiting. Everyone is talkingabout electromobility. We will show youour contribution to this exciting deve l -op ment.

For example with the results from theBoxster E research project, a fully elec -trically powered Porsche Boxster, whichmarks a new chapter in Porsche Intelli -gent Performance and for which wedeveloped, constructed, and tested thehigh-voltage battery among other things.

Porsche Engineering Magazine 1/2011

ANNIVERSARY

Pioneering performance for 80 yearsPorsche Engineering

About Porsche EngineeringImpressumEditorial

ELECTROMOBILITY

Intelligent ways to innovative performanceThe Boxster E research project

Thermal managementNew thermodynamic solutions for electro mobility

Mobility goes electricThe Porsche Hybrid RS mountain bike andthe Seabob


Contents

Cover

Ferdinand Porsche had been working on electro-mobility long before 1942, when the cover photowas taken – what would he have had to say about the Boxster E?

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The Panamera S HybridThe Porsche Gran Turismo sets a new benchmark for its class 40

News

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Contents

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Innovation as a traditionAn interview with the Managing Directors ofPorsche Engineering

7Porsche Engineering Magazine 1/2011

History

Over many decades, Porsche Engi-neering has built up a reputation asan excellent and multi-faceted engi-neering service provider

Interview

The Managing Directors of Porsche Engineering discuss the traditionand future of the engineering service provider

Research

Cutting-edge research for electro-mobility: the Boxster E researchvehicle, for which Porsche Engi-neering developed, constructedand tested the high-voltage battery

Development

Innovative thermodynamic solutions for thechallenges of electromobility

Contents

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For the Porsche Museum in Stuttgart-Zuffenhausen, the 80th anniversary ofengineering services by Porsche, whichwas founded way back in 1931, is oneof the central themes of 2011. From June21 to September 11, 2011, the specialexhibition “80 Years of engineeringservices by Porsche” is paying tributeto the most important and interestingcustomer projects of the past eight de-cades. On display are ap proxi mately 20special exhibits extending from the de - velopment of entire vehicles via engi-nes and transmissions to remarkablein dus trial projects of the present day.The ten vehicles on display engineeredby Porsche include a 1931 vintage Wan -derer sedan, the legendary Auto UnionGrand Prix racing car and the Audi SportQuattro S1.

Porsche Museum special exhibitionThe Porsche Museum is open Tuesdayto Sunday from 9:00 a.m. to 6:00 p.m.

For further information please visit:www.porsche.com/museum


News

The Porsche Museum in Stuttgart-Zuffenhausen

Just in time for the 10 year anniversaryof Porsche Engineering s.r.o., Prague,the engineers at the Czech subsidiaryare moving into their new offices. ThePrague office specializes in complextechnical calculations and simulations.This involves using all the latest de -velopments and methods from currentresearch. For this reason, PorscheEngineering has been working closelywith the Technical University in Praguefor a number of successful years.

The Prague office moves into a new building

NEWS

Historical edition

News


The Porsche Classic Cooler is the per-fect synthesis of technology and design.A genuine Porsche original. The exclusivebottle cooler was developed as part of ayoung talent development program by tenyoung engineers at Porsche Engineeringfor the Porsche Design Driver’s Selection.

The design language of the PorscheClassic Cooler is defined by the use ofan original ribbed cylinder and thereforeemanates the simple and pure design ofthe early air-cooled Porsche 911 engine.The participants in the program were in-volved in the entire development pro-cess for the bottle cooler – from thevery first idea to the finished product.

The Porsche Classic Cooler is available in Porsche Design Driver’s

Stay coolThe Porsche Museum is also highlighting80 years of the history of Porsche Engi-neering with a further publication in theseries “Porsche Museum Editions.” Thepublication includes approximately 200pages of the most interesting customerprojects from the last 80 years. Numer -ous photographs, drawings and docu-ments from the Porsche archive collec-tion provide a real insight into the workof Porsche engineers — material which isnormally strictly labeled “top secret”.

The book is available for 14.90 Euro inthe museum shop and in retail stores.

The Swedish commercial vehicle manu-facturer Scania is developing a new gen -eration of truck cabs with Porsche En -gineering. “In Porsche Engineering, wehave found a partner that shares Scania’svalues and views on development andproduction. We will develop a cab frametogether that is optimized for Scania’srequirements on styling and functionality,as well as for rational production,” saysPer Hallberg, Executive Vice Presidentand Head of Research and Development,Purchasing at Scania.

Selection Shops and online: www.porsche.com/shop

Scania relies onPorsche Engineering

Anniversary History

Pioneering performance for 80years – Porsche EngineeringON APRIL 25, 1931, FERDINAND PORSCHE FOUNDED AN ENGINEERING OFFICE UNDERTHE NAME OF “DR. ING. H.C. F. PORSCHE GESELLSCHAFT MIT BESCHRÄNKTER HAFTUNG,KONSTRUKTION UND BERATUNG FÜR MOTOREN- UND FAHRZEUGBAU” IN STUTTGART.TODAY ENGINEERING SERVICES BY PORSCHE OPERATES UNDER THE NAMEPORSCHE ENGINEERING AND HAS DEVELOPED PROJECTS FOR AUTOMOBILE MANU-FACTURERS, SUPPLIERS AND OTHER INDUSTRIAL COMPANIES FROM ALL OVER THEWORLD FOR MORE THAN 80 YEARS.

Anniversary History

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The engineering services companyPorsche Engineering Group GmbH hasits roots in the oldest Porsche AG compa-ny. On April 25, 1931, Ferdinand Porscheregistered a design bureau named “Dr.Ing. h.c. F. Porsche Gesellschaft mit be-schränkter Haftung, Konstruktion und Be-ratung für Motoren- und Fahrzeugbau”in Stuttgart. At that time, the companyfounder, Ferdinand Porsche, had alreadybuilt up more than 30 years of experi -ence working successfully for the leadingautomobile manufacturers of his time.

Ferdinand Porsche, the automotive designer

The name Porsche has been associ -ated with pioneering innovations in auto -motive engineering since the beginningof the last century. Ferdinand Porschehad already been busy de s igning anddeveloping his first cars as far back as1896. The first fruit of this endeavorwas an electric vehicle known as the“Lohner - Porsche” driven by steer edwheel hub motors that caused a sen -

sation at the Paris World Exhibition in1900. No less visionary was FerdinandPorsche’s next idea: again in 1900 hecombined his battery-powered wheelhub drive with a petrol engine – theprinciple of the serial hybrid drive hadbeen born.

With the first functional, full hybrid carin the world, the “Semper Vivus” (“al-ways alive”), Ferdinand Porsche hadentered uncharted territory in terms oftech nol ogy. In this vehicle, two genera-

Dr. Ing. h.c. F. Porsche AG, Stuttgart, has been the leading manufacturer of premium

sports cars for more than six decades. This success story of Porsche AG is however

also based on decades of development experience, stretching far beyond just building

sports cars. Over many decades, Porsche has built up a reputation as one of the best

known and multi-faceted engineering service providers in the world.

80 years of engineering services by Porsche

1950, Prof. Ferdinand Porsche (third from left) and Ferry Porsche (second from left) examining an engineering drawing in their office


Anniversary History

13

tors twinned with petrol engines formeda single charging unit, simultaneouslysupplying electricity to wheel hub motorsand batteries.

As a full hybrid concept, the “SemperVivus” was also able to cover longer dis -tances purely on battery power until thecombustion engine had to be engagedas a charging station. To save weightand create space for a petrol engine,Ferdinand Porsche used a compara- ti ve ly small battery in the “Semper Vivus”with only 44 cells. In the middle of thevehicle he installed two water cooled3.5 hp (2.6 kW) DeDion Bouton petrolengines for generating electricity, driv -ing two generators, each producing2.5 hp (1.84 kW). Both engines oper -ated independently of one another, eachdelivering 20 amps with a voltage of 90volts. Starting as far back as 1901 as theLohner-Porsche “Mixte” and from 1906onward as the “Mercedes Electrique”,Ferdinand Porsche brought his hybriddrive to series production.

which the Austro-Daimler works teamwon the first three places in the 1910running of the highly regarded PrinzHeinrich Race. In the guise of the Austro-Daimler “Sascha”, he developed a smallcar which prevailed against its largerdis placement competitors in the 1922Targa Florio, notching up no fewer than43 racing victories in total.

This was followed in 1906 by the nextstep in Ferdinand Porsche’s career. Atthe tender age of only 31 he landed theposition of Technical Director at AustroDaimler in Wiener Neustadt, putting himin charge of the products of one of Eu - r ope’s leading automotive companies.One of the greatest successes of this erawas the so-called “Prinz-Heinrich Car”, in

Left: 1900, an original sketch of the Lohner-Porsche electric car

Below: 1900, the Lohner-Porsche electric car at the ParisWorld Exhibition

1922, the Austro-Daimler “Sascha” Type ADSR-I at the Ries Race in Graz in Styria, Austria


Anniversary History

and used in international automotivemanufacturing over many decades is alsoheld to be a milestone in automotivehistory.

In the spring of 1933, Ferdinand Porschewas commissioned by Auto Union inSaxony to develop a 16-cylinder rac ingcar according to the new 750 kilogram(approximately 1653 pounds) rac ing for -mula. By January 1934, the Auto UnionP racing car (P for Porsche) had already

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1933, the Porsche Type 7 for Wanderer, the first Porsche customer project

1931, the patented Porsche torsion bar suspension(Porsche Type 17)

In 1923 Ferdinand Porsche moved tothe Daimler engine company in Stuttgart-Untertürkheim as Technical Director.There, in addition to the Type 8/38 mid-sized model and the first eight-cylinderengine Mercedes-Benz, the “Nürburg”Type 460, it was first and foremost thesupercharged sports and racing carsthat further consolidated his worldwidereputation as an automotive designer.In January 1929 he left Daimler-BenzAG. Following a short interlude at theAustrian Steyr plant, he returned toStuttgart at the end of 1930 and openedan engineering office.

The founding of Porsche’s engineering office

On April 25, 1931, at the height of theworld economic crisis, “Dr. Ing. h.c. F.Porsche Gesellschaft mit beschränkterHaftung, Konstruktion und Beratung fürMotoren- und Fahrzeugbau” was enteredinto the commercial register in Stutt-gart. The work of the team under Ferdi-nand Porsche, initially comprising twelvepeople, covered the entire scope ofautomotive engineering from the verybeginning.

1927, the Mercedes Benz Type S at a tribute to Otto Merz on the occasion of his winning the GermanGrand Prix


As early as 1931, Porsche designed asix-cylinder average mid-size saloon forthe Chemnitz car manufacturer Wandereras well as a new in-line eight-cylinderengine. In addition, the engineering of- f ice developed a small car for ZündappGmbH, which with its rear-engine, rigidtubular backbone chassis and transmis-sion mounted forward of the rear axlewas to prove to be decisive for the Volks -wagen that came later. The torsion barsuspension patented on August 10, 1931

Anniversary History

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In November 2007, the Porsche Museum decided to under -take one of the most interesting and challenging projects inits history: the faithful reconstruction of the Lohner-Porsche“Semper Vivus” from 1900. The construction of the first hy-brid automobile in the world was still a huge challenge for allthose involved in the project, even 100 years after its inven-tion. The aim was not only to recreate a car that looked exactlylike the original down to the finest detail, but also one withexactly the same driving performance. The Porsche Museumcontracted the mechanical work to an expert team under thebodywork specialist Hubert Drescher. Along with numerousother racing car projects, the aluminum body of the PorscheType 64 exhibited in the museum also originates from Dre-scher’s workshop in Hinterzarten.

Before work could be started, extensive research had to becarried out in various archives all over Europe. Finally, a hand-ful of black and white photographs and an original technicaldrawing provided the basis to start work. Just as FerdinandPorsche had once worked, the reconstruction of the “SemperVivus” began first of all on paper. As neither technical specifi-

cations nor other helpful drawings are extant, experts had toinstead create technical drawings and calculation tables theold-fashioned way, by hand on graph paper. Additionally,existing photos and drawings were painstakingly studied andmeticulously measured. As no functioning wheel hub motorstill exists, technical details such as driving performance andrange had to be calculated and figured out from scratch.

When selecting materials, the bodywork specialist Drescherlooked to coaches and carriages from the beginning of the19th century for inspiration. This also required the support ofexperienced suppliers, who have solid expertise in the manu-facture of unusual materials. The fully functioning replica ofthe “Semper Vivus” does not just consist of re-manufacturedparts however: original combustion engines, which functionas generators, were found and incorporated into the recon-struction.

The highly impressive result of the restoration of the “SemperVivus” was on show at the world premiere of the Porsche Pana -mera S Hybrid at the International Motor Show in Geneva.

The recreation of the “Semper Vivus”

Hubert Drescher restoring the “Semper Vivus” and in the car on the Porsche “skid pad” in Weissach

Lohner Porsche


Anniversary History

set three world records and won threeinternational Grand Prix races in addit ionto several hill climb races. Between 1934and 1939, with drivers such as Bernd Ro-semeyer, Hans Stuck and Tazio Nuvolari,the constantly refined Auto Union racingcar became one of the most successfulpre-war era racing cars. Its mid-enginetechnical design proved to be a trendset-ter for all modern racing cars and is usedto this very day in Formula One.

Pioneering developments

In addition to developing racing cars,since 1933 the engineering office hadbeen equally hard at work on the designof a low-cost, small car commissioned bythe NSU works. When Ferdinand Porschebegan work on designing the Type 32compact car, this was already the sev -enth small car design of his career. Anumber of prototypes of this vehicle typewere built, which with the air-cool ed,flat-four, rear-mounted engine and Por-sche torsion bar suspension ex hibit eddis tinct similarities with the later Volks-wagen Beetle.

The “Memorandum on the constructionof a German people’s car” (Volkswagen)that he presented to the Reich TransportMinistry on January 17, 1943 was to provecritical to the breakthrough of the smallcar concept. Shortly thereafter, on June22, 1934, he received the official orderfrom the RDA, the “Reichsverband derDeutschen Automobilindustrie” (GermanReich Automobile Industry Association)to design and build the Volkswagen Type60 and Volkswagen prototypes, whichwere assembled in the garage of his Por-sche villa in the north of Stuttgart in 1935.

ver arrows” between 1937 and 1939 aswell as the design of the Type 80 high-speed car for an attempt on the landspeed record.

In 1938, the Volkswagen works awardedthe Porsche engineering office the con-tract to develop a racing car based on

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Alongside the Volkswagen project, thePorsche engineering office, located in theZuffenhausen district of Stuttgart since1938, was working on numerous otherdevelopment contracts from the automo-tive industry. For Daimler-Benz AG, workincluded the development of technicalengine components for the Mercedes “sil-

1937, the Auto Union P racing car on the Nürburgring (Type 22)

1934, the prototype built for the NSU (Type 32) in front of the Porsche engineering office in Kronenstrasse 24


Anniversary History

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the Volkswagen Type 60, which was totake its place on the grid for a plannedlong distance race from Berlin to Romeas a promotional event for the “KdF” car(“Strength through Joy” car). By thespring of 1939, the Porsche engineershad developed three sports car coupésunder the in-house designations Type64 and Type 60K10, for the “Non-stopspeed endurance test” scheduled forSeptember, which however never tookplace because of the outbreak of theSecond World War. With a sleek, stream-lined aluminum body, shrouded wheelwells and a modified VW horizontallyopposed engine, the record-breakingcar, weighing a mere 600 kilograms(approximately 1,322 pounds), reacheda speed of over 140 km/h (87 mph).

The Second World War

After the outbreak of the Second WorldWar, other types of vehicles were devel -op ed on the basis of the Volkswagen formilitary use. In addition to the Type 81

“VW Kastenwagen” the company, trad -ing as Porsche KG since the end of1937, developed the Type 62 “KdF off-road vehicle”, the Type 82, known as the“VW Kübelwagen” and the all-wheel driveType 87 and Type 166 “VW Schwimm -wagen” amphibious vehicle. A commis-sion then came from the ArmamentsMinistry to design and build militarytanks between 1939–1942. It resultedin two prototypes, however the tanksnever saw military action.

New beginning with engineeringservices and sports car construction

The most important customer in theearly post-war years was the Italiancompany Cisitalia, whose car enthusiastowner Piero Dusio awarded numerousdesign contracts at the end of 1946.Besides a tractor and a water tur b ine,Dusio also ordered a mid-engine sportscar with hydraulic torque converter anda Grand Prix racing car. The result was

1938/39, the Type64 is consideredthe forefather of allPorsche sports cars

1941, a tropical delivery vehicle based on the Type 82


Anniversary History

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From the engineering office to theWeissach Development Center

Despite the successful entry into vehiclema nufacturing, customer projects re -main ed a firm fixture in the then PorscheKG’s service portfolio. The most impor-tant client right into the 1970s wasVolkswagen AG, with whom an extensivecoop eration agreement had been made.Numerous detailed improvements weredevised for the VW “Beetle”. Porsche wasalso involved in developing the succes-sor models for the successful “Beetle”.The Stuttgart-based company devel -op ed numerous prototypes on behalfof the Volkswagen Group, which wereto prove groundbreaking for the VW’spassenger vehicle product portfolio. Thebest-known customer pro jects were theVW Porsche 914 unveiled in the autumnof 1969 and the Porsche 924 built inresponse to Volkswagen developmentcontract EA 425.

In addition to the numerous ordersfrom the Volkswagen Group, Porsche’s

In July 1947, independent design workbegan on the Type 356 “VW sportscar”. The design concepts became real -ity in the first half of 1948 as a prototypeunder the in-house design number 356,based on earlier designs such as theVolkswagen or the Type 64 “Berlin-Romecar”. Once the chassis had completedits maiden drive in February, the finish ed prototype with the chassis num-ber 356-001 received one-off approvalby the State Government of Carinthiaon June 8, 1948. The Porsche sportscar brand had been born.

1958, developments for Volkswagen: the Type 60, Type 728, Type 726/1 and Type 726/2 (from left to right)

the Type 360 “Cisitalia” completed in1948, which was technically far ahead ofits time. Unlike the front-engine FormulaOne racing cars of the post-war years,which usually still featured rigid axles,the Type 360 was designed with a mid-engine layout. The suspension featureddouble trailing arms on the front axle, therear axle being configured as a double-joint swing axle with torsion bar suspen -s ion. The drive train of the single-seaterwas a 385hp (283 kW) 12-cylinder en -gine with compressor, achieving a maxi-mum engine speed of 10,600 rpm.

Left: 1948, technically ahead of its time: the Porsche Type 360 “Cisitalia”

Above: 1948, the 356 No. 1 Roadster


Anniversary History

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1983, theFormula 1 engine,the “TAG Turbomade by Porsche”for the McLarenracing team

engineering services developed numer -ous other pioneering innovations for do -mestic and foreign clients in the 1950sand 1960s. Porsche developed the am-phibious all-wheel-drive Type 597 Jagd-wagen vehicle in response to a Bundes-wehr invitation to tender. Although thePorsche Jagdwagen proved to be techni-cally superior, the contract was award edto car and motorcycle manufacturer DKWfor labor market reasons.

In 1961, Ferry Porsche laid the founda-tion stone for Porsche’s research anddevelopment center in Weissach, ap-pro xi mately 25 kilometers (15.5 miles)north west of Zuffenhausen in Stuttgart.He had already had a so-called “skidpad” built there 10 years earlier, whichhad been used ever since for conduct -ing suspension tests. In 1971, Porsche’sdevelopment division with its construc-tion, tes ting and design departmentsrelocated to the newly constructed de-velopment center in Weissach. Alongsidethe “skid pad”, a large test track as wellas high-spec installations such as a windtunnel, crash facility, emissions testing

center and a wealth of engine test rigswere built and made avai l able for cus -tomer projects and in-house develop-ments alike.

For example, in the 1980s, the engineersat Weissach developed the “TAG Turbomade by Porsche” engine for the BritishMcLaren International racing team, withthe aim of causing a sensation at thevery pinnacle of motor sport. The secretof the Formula One high-performanceengine’s success lay in marrying turbo-charger technology with an electronicengine management system. As a conse-quence, the racing car’s fuel consump-

1969, the VW-Porsche 914 1970, the construction of the first development center building in Weissach


tion was particularly economical, whichcritically influenced racing strategy.

AvtoVAZ, the largest passenger vehiclemanufacturer in Russia and EasternEu r ope, also relied on the technical exper-tise of Porsche’s engineering services.The Weissach engineers were assignedwith revising the five-seat Lada Samarain order to achieve a competitive priceand the necessary sturdiness for roadconditions in the Soviet Union. With theexception of the styling, nearly all as-semblies such as the motor, transmis-sion, chassis, body, acoustics and elec-tronics were optimized or redeveloped.

Anniversary History

Industrial projects

Being innovative has a long traditionat Porsche Engineering. For example,Porsche designed the cockpit layout forwidebody aircraft in cooperation withaircraft maker Airbus in the early 1980s,and set the trend through the use ofmonitors instead of conventional analoginstruments. The project’s goal was tonoticeably improve working conditionsfor pilots by optimizing the visual designof the cockpit.

A milestone in the development of ve-hicles for industry was the beginning ofa cooperation with Linde Material Hand-ling, which continues successfully to thisvery day. Having already designed slew -ing gears and chain drives for Linde, inthe early 1980s the sports car manufac-turer Porsche was retained to design anew generation of forklift trucks. Porschestyling for Linde’s products has sincebe come a multiple award-winning trade-mark. For instance, Linde forklifts havejust recently once again received thecoveted “red dot award for productdesign” from the prestigious North RhineWestphalia Design Center: the electriccounterbalance E20-E50 forklifts earn edthis distinction in 2011 and thereforecontinue the award-winning traditionwhich includes over 20 design awardssince the beginning of the cooperationbetween Porsche Engineering and Linde.For Linde Material Handling, productdesign has become an integral part ofthe “Linde” brand and a clear compe ti -tive advantage. In addition to design,Porsche Engineering also assists LindeMaterial Handling with other develop-ment projects.

Series development and production

From the late 1980s and early 1990sonwards, Porsche’s engineering ser -vices team worked for Daimler-Benz AGon the design and test aspects of aW 124 series saloon fitted with the 5 liter,V8 four-valve M 119 engine. With thefour-speed automatic transmission fit-ted as standard, the Mercedes-Benz500 E reached the 100 km/h mark (62mph) in only 5.9 seconds, with the topspeed electronically limited to 250 km/h(156 mph). In the process, the contractfar exceeded the usual development ac-tivities. Series production together with

Above: 1981, the Airbus cockpit; below right: 1990, the Mercedes 500 E

the assembly of the body shell and finalassembly took place at Porsche’s Zuffen-hausen works. The Dai mler-Benz worksin Sindelfingen were responsible for thepaint finish and delivery. Production ofthe Mercedes-Benz 500 E started up inthe spring of 1990.

Porsche’s department for engineeringservices also entered into a joint venturewith Audi to develop a high-performanceversion of a series vehicle. The high-performance sport station wagon, theAudi Avant RS2, unveiled in the autumnof 1993, came into being in Weissach asthe 315 hp variant of the all-wheel driveAudi Avant S2. This borrowed numer ousPorsche components, such as for ex -ample wheel hubs, high-performance

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Award-winning design since the 1980s: the LindeE25 forklift, which received the red dot award in 2011


Anniversary History

Today, as in the past, Porsche Engineeringis grappling with the engineering chal -lenges of the future. Be it the solid exper -tise in the area of electromobility thatPorsche Engineering displayed in theBoxster E research project in 2011 or inthe development of the Seabob seriesproduction sports watercraft in 2007, ex-perience in the lightweight constructionand downsizing, but also thinking outsidethe box with the development of a pre-mium outdoor barbecue in 2008 –Porsche engineers dedicate themselvesto each project with the same commit-ment to ultimate quality, innovativedesigns and customized solutions.

On the road since 2002: the 115 hp V2 enginefor the “V-Rod” by Harley-Davidson

Electromobility is advancing: Above: 2011, the Boxster E research project

Below: 2007, the Seabob sports watercraft

Nowadays, all development projects forcustomers worldwide are managed bythe Porsche Engineering Group GmbH(PEG) founded in 2001 with headquar- t ers in Weissach. By networking all ofthe Porsche Engineering locations inGermany and abroad, and sharing infor-mation closely between project teams,PEG offers interface competency andlat eral thinking, ensuring that customerprojects are delivered consistently andproductively, and without any hitches.

The combined expertise of Porsche En-gineering’s engineers and the compre-hensive resources at the Weissach Deve-lopment Center’s disposal form the basisof its innovative services with the high -est quality standards. But the publiconly gets to see the tip of the iceberg.Thanks to extremely strict confiden -tiality, Porsche Engineering protects itscus tomers’ product strategies and brandidentities with the greatest care at alltimes. Only very few projects are knownof, and only with the customers’ explicitconsent. Because Porsche Engineeringonly succeeds if a customer returns. Thismaxim prevails to this day – as it has formore than 80 years.

Want to find out even more? Discoverexciting developments from 80 years ofengineering services by Porsche in ourweb special: www.porsche-engineering.com/80years


brakes and rims. Exterior parts such asfog lights and indicators as well as theexterior mirrors also came from thePorsche 911 of the then current 993model series. The Audi Avant RS2 wasbuilt at Porsche’s Zuffenhausen worksbetween October 1993 and July 1994.

Design study

At the Beijing International Family CarCongress, Porsche presented the C88study in November 1994, which wasdeveloped especially for the Chinesemarket. The automobile constructedunder the project name C88 catered tothe needs of Chinese customers andwas designed in three versions: in addi-tion to an extremely affordable, two-door version, a standard and four-doornotchback luxury version were alsoplanned. The development goals alsoaccounted for simple manufacturingmethods, a high quality standard andhigh level of vehicle safety.

Into the future with tradition andinnovation

In 2001, under the development name“Revolution Engine”, Porsche Engineer -ing started work as a developmentpartner on developing a new V2 enginefor the American motorbike manufac- t urer Harley-Davidson’s “V-Rod” model.Against the backdrop of a collaborativerelationship stretching back to the 1970s,Porsche engineers designed a water-cooled, 1,131 cc power unit based on aracing engine which delighted discern -ing Harley-Davidson customers withits performance and engine sound inequal measure.

Anniversary Interview with the management

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Mr. Radmann, Mr. Lappe, this yearmarks the 80th anniversary of Por-sche’s engineering services. Howdoes this history influence the workof Porsche Engineering today?RADMANN: Our 80-year anniversaryis an important event for us. The storyof Porsche Engineering, which began in1931 when Ferdinand Porsche foundedan engineering office, defines the waywe think and act every day. In past dec -ades, we have shown that the Porschebrand stands for excellent quality, long-term customer relationships and highlyinnovative technologies. This has shap edour drive and our commitment.

One doesn’t normally associatePorsche with the engineering ser -vices provider Porsche Engineering,but with the manufacturer of sportscars ...RADMANN: Correct. However, thosesports cars would not have been possib lewithout the engineering services work ofFerdinand Porsche. The success story ofPorsche AG today is also based on theexperiences Ferdinand Porsche gather -ed in engineering ser vices before thecre ation of the Porsche automobilebrand. The engineering services are anessential part of the Porsche brand core.LAPPE: And even before the foun -dation of Porsche’s engineering ser -


Malte Radmann, Managing Director of Porsche Engineering

Innovation as a tradition

For more than 80 years, Porsche has developed tailor-made engineering solutions for

its customers. Malte Radmann and Dirk Lappe, the Managing Directors of Porsche

Engineer ing, explain how Porsche Engineering supports its customers in the projects

of today and helps them to solve the challenges of the future. They also discuss which

role the 80-year tradition plays in their everyday work.

23

vices in 1931, Ferdinand Porsche had al-ready been active in the developmentfor the automotive industry for a longtime – for example in the developmentof the first serial hybrid vehicle in theworld in 1900, the "Semper Vivus". Al-ready at this time, Ferdinand Porschewas build ing up experience in the areaof hybrid technology.

Porsche Engineering as an essentialpart of the Porsche brand core – onemight ask the question then, howmuch of your customers’ expertisegoes into a Porsche sports car?RADMANN: Without the trust of ourcustomers in our absolutely reliableconfidentiality, the last 80 years wouldnever have been such a success storyfor our customers and for us. Confiden-tiality is our top priority. Only with theexplicit permission of our customers weeven mention their names – like we didfor example with our recent coopera-tion with the truck manufacturer Scania.

What areas of expertise does Por-sche Engineering offer?LAPPE: We define ourselves through ouroutstanding total vehicle competence,both in the development of new vehiclesand vehicle derivatives. We also considerthe smallest parts and their role in thevehicle as a whole when developing com-ponents and assemblies. In this area,customers benefit from the expertise ofthe sports car manufacturer Porsche. Weare able to take every development toproduction readiness.

How important is the Weissach re -search and development center forPorsche Engineering in this context?

employees is also concentrated in thisarea. In combination with the compre-hensive testing facilities and engineerswith project experience at our other lo-cations, we are able to offer tailor-madesolutions to customers from a variety ofindustries.

What sets the employees of PorscheEngineering apart?LAPPE: First and foremost, their ex -per tise in their respective field sets.How ever, that alone is not enough fora service company. We strategically cul-tivate interdisciplinary thinking amongour employees. This means that a pro-

LAPPE: Weissach is and will always bethe central development resource forPorsche innovations, for both sports carsand engineering services. We have thenecessary infrastructure that enablesthe development of high-tech solutionsand testing up to production readiness.The knowledge of more than 2,500



Dirk Lappe, Managing Director of Porsche Engineering

“The engineering services arean essential part of the Porschebrand core.”(Malte Radmann)

24 Porsche Engineering Magazin 1/2011

ject is viewed from as many differentperspectives as possible. Our emplo y -ees also contribute another very impor-tant qualification, which we at Porschevalue just as much as our customers:the ability to think outside the box andto create solutions that are not apparentat first glance.

What character does this kind of lateral thinker have?RADMANN: Having solid expertise inyour field and enjoying figuring outcom plex puzzles are important require-ments for interdisciplinary lateral think -ing. You also need to have the abilityto think outside your own box, your owndiscipline, that’s essential. However, atthe end of the day it’s often a person’spersonality which decides whether wedecide in favor of someone or not. Everysingle em ployee communicates directlywith our customers and his or her per-sonality and social competence is thedeciding factor for whether our custom -ers come back.

What defines the corporate culture ofPorsche Engineering?LAPPE: First of all, a good blend of high-ly experienced employees and young,well trained junior staff. We offer dedicat -ed colleagues the opportunity to quicklyassume responsibility due to very leanorganizational structures. For us, pro-fessional management of our interns isthe basis for winning over new potentialemployees for our company early on. RADMANN: Our colleagues have thewill to make a difference. They are veryperformance-oriented and display initia -tive. Our employees value team spirit, afriendly working environment ...


LAPPE: ... and most importantly, pas-sion, a sense of humor, and taking plea-sure in everyday work.

You have already mentioned thatPorsche Engineering is working onprojects in various industries. Soyou don’t just concentrate on theautomotive industry?RADMANN: Correct, in the 80 years ofPorsche Engineering, we have repeated-ly proven our development abilities in avery large number of fields such asshipping, power engineering, agricul -ture, load-carrying vehicles, in competi -tive and aquatic sports, and in the healthsector. In our work, we always focus ontransferring our expertise from theautomotive industry to other, relatedsectors. In this way, we tap valuable syn-ergies for entirely different fields.LAPPE: The industrial landscape of-fers big potential for engineering ser -vice providers. Our many years of suc-cessful coop eration with the forkliftmanufacturer Linde, for example, is clearevidence of this potential. But at thesame time, the automotive industry isstill very important for us and is aboutto go through dramatic changes, whichwe as an engineering services providerare able to support our customers inhandling.

Are you talking about electromo-bility?LAPPE: Exactly. Whatever role thespread of electrification assumes in thefuture, we at Porsche Engineering arecapable of developing hardware andsoftware for the widest range of electro-mobility solutions. We have shown in theBoxster E research project, for example,

how to develop a high-performance, ful-ly electric sports car. Whether fast charg -ing processes, thermal management,crash safety or battery managementsys tems: the quality of our solutionsremains true to the Porsche name.RADMANN: We started to work onelectromobility at a very early stage.The structure and staff of our organiza-tion is oriented towards this develop-ment, so that we can offer our custo-mers comprehensive expertise in theareas of full hybrid, plug-in hybrid andelectric vehicles.

What's the situation with range ofelectric vehicles that have beendeveloped so far? Are you alreadyhappy with the status quo here?LAPPE: That really depends funda-mentally on what the electric vehicle isbeing used for. As a complete replace-ment for a vehicle with a combustionengine, electric vehicles and their cur-rent technology are naturally not suffi-cient. But it is very possible that a vehi-cle with a range of only 93 miles wouldbe more than enough for the majorityof the population. The daily dis tancedriven by the average person is actuallya lot less. If someone wants to drive forlonger distances, then a vehicle with arange extender or an efficient full hybridwould be required. But we also have not

reached the end of the road yet when itcomes to battery development. We’reworking extremely hard on optimizingcell efficiency. The cell manufacturers arealso continuously improv ing the storagecapacity.

So, in your opinion, is electromobil -ity the most significant trend thatwill define the automotive industryof the future? RADMANN: We see electromobility asone of many trends in the same direc-tion: increased automobile efficiency.Apart from the increasing electrification,this also includes lightweight construc-tion with high-tech synthetics such ascarbon-fiber-reinforced plastic, the opti-mization of gasoline and diesel engines,as well as what’s known as downsizing.We assume leading development re -sponsibilities in all these fields and arecontinually increasing our high perfor-mance.LAPPE: It is possible that we are moreable to intelligently link a wide range oftechnological developments than otherengineering service providers, becausewe can utilize our experience from thedevelopment of Porsche sports cars.They are also defined by an intelligentcombination of the latest technologicaladvances and set standards not just inthe sports car sector.

Could you summarize the idea andcommitment of Porsche Engineeringin one sentence?LAPPE: We view ourselves as a reliablepartner for our customers, who devel -ops first-class technological solutionsthat consider the entire product up toproduction readiness.



“We are capable of developinghardware and software for thewidest range of electromobilitysolutions.”(Dirk Lappe)

Intelligent ways to innovative performanceWITH THE DEVELOPMENT OF THREE BOXSTER E RESEARCH VEHICLES, POWERED EXCLUSIVELY BY ELECTRICITY, A BRAND NEW CHAPTER IS OPENED IN PORSCHEINTELLIGENT PERFORMANCE. PORSCHE ENGINEERING WAS RESPONSIBLE FOR THEDEVELOPMENT, CONSTRUCTION AND TESTING OF THE HIGH-VOLTAGE BATTERY ANDPROVIDED SUPPORT IN THE AREAS OF OPERATIONS AND DISPLAY, THERMALMANAGEMENT AND BATTERY MANAGEMENT SYSTEM DESIGN.

Electromobility Boxster E

Boxster E research project


28

Porsche Intelligent Performance:the Boxster E research project

Performance is nothing without intelli-gence. More horsepower alone doesnot win the race. Only ideas drive theadvancement of real progress. For moreefficient engines, lighter car bodies andinnovative drive technologies.

Such as with the completely hybrid se-ries vehicles, the Panamera S Hybrid andthe Cayenne S Hybrid, which impresswith lower fuel consumption but thesame sportiness and elegance. Or withthe hybrid super sports car, the Porsche

918 Spyder, a concept car unveiled in2010 which is being developed for seriesproduction as fast as possible.

Additional research projects and racingexperiments such as the mid-engine


The Boxster E – a research vehicle with the mark of Porsche Intelligent Performance

The future of mobility is setting new challenges for the automotive industry.

The intelligent combination of efficiency and performance through the optimized use

of innovative technology provides answers to the mobility needs of the future. This

principle, Porsche Intelligent Performance, is embodied by all Porsche development

projects and is paving the way to the future.

29

hybrid Coupé 918 RSR embody the ideasof Porsche Intelligent Performance andprovide ways to research methods forachieving more sustainable improve-ments in efficiency.

With the development of three complete -ly electric Boxster E research vehicles,another great leap is made in the devel -opment of cutting-edge technol ogy forthe future of mobility.

The electromobility challenge

“Electromobility is the most importantchallenge of the next few years and theengineers at Porsche are determined toachieve the kind of outstanding resultsthey always obtain, in order to meet thischallenge,” said Matthias Müller, CEOof Porsche AG, during the presentationof the first of the three brand new electricBoxsters. Early in 2011, Matthias Müllerdrove the first few almost silent meterswith the former federal state leader ofBaden-Württemberg, Stefan Mappus, inthe impressively sporty research vehiclein front of the equally impressive PorscheMuseum in Stuttgart. “The Boxster E, asa laboratory on wheels, will help us signif -icantly to solve the practical problemsof electromobility, and meet our custom -ers’ high expectations,” says Müller.

Federal Government created a strongfoundation for achieving their ambi-tious and stated goal of getting onemillion electric cars on the road in Ger-many by 2020. The first research anddevelopment projects and regional pi-lot programs were implemented alongwith the Economic Stimulus Package IIand 500 million Euro of funding be -tween 2009 and 2011. It was in thiscontext that the Porsche Boxster with apurely electric drive was developed.

The Boxster E research project is partof the regional pilot program in Stuttgart,one of eight “Electric Mobility Pilot Re-

Electromobility is setting significant chal-lenges for the automotive industry. Cus -tomer requirements and the utilizationprofiles customers expect must be har-monized with what is technologicallypossible and ecologically sustainable. Allover the world, governments and agen-cies are funding countless different initia -tives to encourage development in thearea of electromobility and the wideruse and acceptance of electric cars.

Developing the future

With the National Development Plan forElectric Mobility in 2009, the German



Knowledge gained from the Boxster E research projectprovides answers to the mobility needs of the future Funding of the Boxster E research project is part of the Stuttgart electromobility pilot program

Efficiency and performance in one: the Boxster E researchvehicle

Supported by


30

gions” in Germany, in which pilot pro-jects for electric cars and electromobil -ity infrastructure are being realized upuntil the middle of 2011. The pilot re-gion Stuttgart is being funded and sup-ported as part of the national programfor “Electric Mobility in Pilot Regions”. TheFederal Ministry of Transport, Buildingand Urban Development (BMVBS) is pro-viding a total of 130 million Euro from theEconomic Stimulus Package II for eightpilot regions across Germany. The pro-gram is being coordinated by NOW GmbH(Nationale Organisation Wasserstoff- undBrennstoffzellentechnologie GmbH).

The aim of the Boxster E research pro-ject is to gain new insights into every-day usability and user behavior, in par -t icular when driving and charging electriccars, using three electrically poweredPorsche Boxsters. This should provideresearchers with valuable knowledgeabout the requirements for future prod -ucts and the relationship between electricvehicles and infrastructure. Are electro-mobility and Porsche a contradiction?

resents a battery with incredible powerand performance. Its maximum output isaround 240 kW, so an extra 60 kilowattsmore than the all-wheel drive Boxster Erequires at full throttle.

High-voltage battery

The high-voltage battery was developedand constructed at Porsche Engineering.It was designed especially to be used inthe Boxster E and delivers a level of per-formance typical of a sports car, while atthe same time being lightweight andoptim ally positioned in the car. The trac-tion battery replaces the combustion en-gine of the conventional series vehicle,normally powered by a mid-engine (seeimage on the opposite page). This has apositive effect on the center of gravityof the vehicle and therefore also on thedriving dynamics.

The cells used are made of lithium ironphosphate (LiFePO4) and are a very goodcompromise between energy consump-tion and performance, while also being

Quite the opposite: efficiency united withperformance are typically Dr. Ing.

Boxster E research vehicle

The design of the Porsche Boxster as amid-engine sports car provides the idealvehicle basis for testing the electric drivein an everyday context. The open-top twoseater is extremely light and enables thenew components, the electric ma ch ine,battery and high-voltage technology, tobe housed safely in the car. At the sametime the high performance associatedwith a Boxster S with a conventional fuel-powered engine guarantees the future-oriented fascination of a sports car withnew technology. The Boxster E researchvehicle exists in two different versions:one with a single electric mach ine thathas an output of 90 kW, and anotherwith two electric machines and 180 kW,making the Boxster E the first Boxsterwith an all-wheel drive (see image above).As an energy storage device, a batterywith a capacity of 29 kWh, of which inprinciple around 26 kWh can be used, rep -


In the version withtwo electric ma -chines, the Boxster Eresearch vehicle reaches an effectiveoutput of 180 kW

very sturdy and safe. The battery is fullycharged at approximately 400 volts. Thetarget is a distance of 170 km (106 miles)in accordance with the New EuropeanDriving Cycle (NEDC). Depending on theway the car is driven, a distance of morethan 150 km (93 miles) is possible. Theresulting electrical currents can reachmore than 600 amperes. Keeping thisunder control is an especially big chal-lenge. This applies especially to theconstruction and selection of the elec-trical components.



The supporting frame of the battery is a lightweight construction made of high-strength aluminum

The cover of the battery is specially coated in order to protect it from electro-magnetic waves

The main structure is provided by a cen-tral supporting frame, which is a light-weight construction made from high-strength aluminum (see image belowleft). All the internal components of thebattery are attached to this supportingframe. Two covers made of glass-fiberreinforced plastic provide protection onboth sides against dirt and moisture. Inorder to shield the battery from electro-magnetic waves, the covers are coatedwith a conductive coating (see imagebelow right).

High-voltage connectors for charging in less than 30 minutes

The cells are housed in a total of tenblock-shaped modules containing 44individual cells each. There are fivemodules in the top half of the battery.Five more modules are positioned sus -pended in the bottom half. The fuse,contactors and distributors are locat edin the top part of the battery. The bat-tery has a total of five high-voltageconnectors for two drive motors, and

The battery in the Boxster E research vehicle is positioned in the same position as the mid-engine of the series vehicle

an air-conditioning compressor, charg -ing device and heater in each. Theinternal charging device is connectedat the high-voltage port, so that thebattery can be charged at a capacity of3.3 kW using a normal household socket.However, a higher charging capacity ofup to 60 kW is also possible with anexternal fast charger, which reducescharging time to under 30 minutes. Thebattery weighs a total of 341 kilograms(751 lbs.).

Stay cool

To ensure that the cells remain in theoptimum temperature range of between–10 and +40° C (+14 and +104 °F),they must be heated or cooled as nec -essary. The battery is therefore ther-mally conditioned while being chargedfor example. One big challenge is keep -ing the battery cool when the car isbeing driven in a sporty manner. In thissituation the battery can lose up to 5 kWof heat, which must be conducted else -where. If the battery were to be cooledusing air, an air volume of 500 liters(17.7 cubic feet) per second would berequired, which could not be achievedwith the amount of space available inthe vehicle. For this reason, five coolingplates are located in the center of thesupporting frame of the battery pack,which cool the cells in the upper andlower modules with liquid.

On the one hand, these plates are opti-mized in such a way that they have ex-cellent contact with the cell modules.This results in the best possible heatconductivity in the cooling agent. Onthe other hand, the cooling channelsare designed so that the pressure los-ses are low and the heat is very evenlydistributed through the plates.

The battery cooling system is also con -nected to the low temperature circuit inthe vehicle. In very low ambient temper -atures, the battery is kept warm by ahigh-voltage heater. In average temper -atures, heat exchange is controlled byan air heat exchanger (cooling sys tem).When cooling is required, the air-condi-tioning compressor takes over.



Just like the fuel cap on every Porsche sportscar, the charging socket is located in the front

Monitoring the battery

When operating lithium batteries, it mustbe ensured that their voltage is always ata specific level, which has been specifiedby the manufacturer. Voltage that is toohigh or too low can reduce the life spanof the cells or in extreme cases damagethem. A similar rule applies to the tem-perature. Cells that are too hot age fast -er, cells that are too cold provide re ducedoutput.

The circuit boards of the “cell control-lers” can be seen on the front of the mo d -ules. The controllers constantly mon - itor the voltage and temperature of thecells. The data measured by them is thenanalyzed in the central battery manage-ment system. This system sends thenec essary information to the motor andthe built-in 220 volt charging device viathe vehicle electrical system. The chargestate of the battery is thus controlledduring charging and driving.

Cross-section of the Boxster E battery showingthe cooling circuit

Fast exchange in only a few minutes

All of the electrical connectors haveplugs which can be quickly detached.The conductors for the water coolingare also connected with water-tight,quick-release connectors from motorracing technology. If a platform lift isavailable, the battery can be changed invery little time using the appropriatetools, which is a particular advantage indevelopment processes.

When the two covers are removed, all ofthe components can be accessed. Thishas advantages for the assembly of thebattery, which can therefore be carriedout very easily and safely.

Test of strength

After the battery has been assembled, itis then extensively tested. At the end of2010, a high-voltage testing facility wasset up at Porsche Engineering in Bietig-heim. There, the battery and the batterymanagement system were tested meti c -ulously, before they were allowed to beput to work in the Boxster E. During test -

ing, all of the basic functions of charg -ing and discharging were first tested atmo derate capacities. Even the unlikelycapacity of over 200 kW was carefullytested.

A very important aspect of testing isthe careful check of all the importantsafe ty features that are relevant to themonitoring of the cells described above.Another important function is the correctcalculation of the charge state of thebattery. Only after the calibration of nu-merous parameters in the system is thecharge state reliably transmitted anddisplayed to the driver in the cockpit.



Porsche Engineering’s expertise in electromobili-ty can also be seen in the development of the dis -play and operating design of the Boxster E

Intelligently into the future

After the successful completion of com-prehensive testing, nothing more impe-ded the battery of being fitted into theBoxster E and the car’s presentation.The result: typical Porsche performancein the charging function and also in driv -ing, from the very first few meters. Andall this without any local emissions. Thetesting of the three completely electricvehicles has resulted in a solid foun -dation for future research and develop -ment in electromobility. You can thereforeexpect a few more chapters in the storyof Porsche Intelligent Performance ...

Electromobility Thermal management

34

Thermal management in vehicles with electric drive system

Up until now, thermodynamics special -ists at Porsche were responsible for effi-ciently conducting waste heat awayfrom the combustion engine, ensuringthermal stability and functionality withan optimized cooling system and reduc -ing fuel consumption at all operatingpoints using sophisticated thermal man -agement strategies. They also had toensure that components, auxiliary equip-ment and the transmission were cooled,ventilated and protected from high tem-peratures.

Electric vehicles have completely chang -ed the core tasks required. Along withcontrolling the temperature in the trac-tion battery and cooling the power elec-

tronics, electric motor and range exten-der, integrating these different coolingsystems and the efficient climate con-trol in the vehicle interior while alsosaving energy is now the main focus.

Because traction batteries in electricvehicles still have a limited capacity incomparison to conventional cars, elec-tric vehicles have a significantly smallerrange. This means that it is of centralim por tance to ensure that all oper atingfunctions are reliable, while also main-taining comfort and the energy effi -ciency of all technical systems. This lim -ited range can be even more drasticallyre duced by auxiliary loads such as heatingand climate control.

Cooling the battery, power electro-nics and the electric motor

From a thermal point of view, there arethree main aspects to take into accountwhen using lithium-ion batteries in elec-tric vehicles. At temperatures below zerodegrees Celsius (32 degrees Fahrenheit),the performance and therefore the rangedrop significantly due to slower chemi-cal reactions taking place in the battery.At temperatures above 30 degrees Cel-sius (86 degrees Fahrenheit) the batterydeteriorates exponentially, while extremetemperatures of above 40 degrees Cel-sius (104 degrees Fahrenheit) can leadto serious and irreversible damage inthe battery.

The ideal temperature for a lithium-iontraction battery is approximately thesame temperature that is ideal for hu-man beings. In order to achieve themaximum power output and a long life -span for the battery, it must be keptwithin an ideal temperature range ofbetween 20 and 30 degrees Celsius (68and 86 degrees Fahrenheit). To achievethis, it must be ensured that the batterydoes not exceed a maximum tempera-ture limit, while heat must also be distrib -uted as evenly as possible in the batterycells.

The thermal influence on a battery,such as fluctuations in the battery’sown temperature caused by resistanceinside the battery, external tempera tures,sunlight and waste heat, must thereforebe monitored and controlled by appro-priate thermal control systems, i.e. bymeans of heating or cooling as neces-sary. This ensures proper functioning

Transforming the drive train into an electric drive sets new

and exciting challenges for the thermodynamics specialists

at Porsche Engineering.


Power electronicsand electric drive Passenger cabin

Coolingand

heating systems

Traction battery

Synergy effects

35

in the temperature range of –20 to+45 degrees Celsius (–4 to +113 de-grees Fahrenheit) as required by cus -tomers.

Depending on the type of electricallypowered vehicle (for ex ample mild hy- b rids, full hybrids, plug-in hybrids, com-pletely electric vehicles), requirementsprofile, battery type, cell chemistry andcell geometry, various cooling agents andmethods can be used. These methodsinclude air-cool ing, cooling with cool antsor refrigerants, and direct cooling orsecon dary cooling.

The latter involves cooling the batteryusing an external low-temperature cooler.Only if necessary, e.g. at high outdoortemperatures, an additional heat ex-changer (chiller) is used to transfer thelow temperature of the evaporating re-frigerant from the climate circuit to thebattery cooling circuit.

Along with the traction battery, it isimportant to take the temperature ofother components in an electric vehi-cle into account, such as electric mo-

development using previously identi-fied performance data and driving pro-file requirements.

The graphic below shows an example ofsome of the results from a thermal sim -ulation of a battery cooling processfor the New European Driving Cycle(NEDC). Based on the calculation ofthe power loss, the increase in the tem-perature of components as well as thecool ing requirement can be defined.Furthermore, the energy requirementsfor var ious cooling systems can be calcu-lated and the optimum design for lowenergy consumption in the entire vehiclecan be selected.

Thermodynamic engineers at PorscheEngineering develop and optimize thevehicle’s entire cooling system, indi -vidual cooling and heating circuits orcomponents according to customer re-quirements. An example of this processis the cooling plate from the traction

tor(s), power electronics and range ex-tenders.

As these systems all operate at differ -ent temperature levels and must becooled to different degrees (see graphicon the left), the aim is always to createsynergy effects by harmonizing all thevarious cooling and heating circuits(see graphic on opposite page). By har-monizing the temperature levels, thenumber of different cooling circuits canbe minimized, which in turn results inlower weight and costs, as well as morespace in the vehicle.

The engineers at Porsche Engineeringselect the cooling agents and methodsas early as during the first design con-cept phase. For this purpose, PorscheEngineering has developed a thermalsimulation tool and validated it in tests.This can be used to work out and definethe optimum cooling and heating sys -tem design at an early stage of vehicle



Time

—— T Targets —— T Coolant —— P Loss —— Speed

Temperature levels

fi

fi

fi

fi

Electric motor

Power electronics

Battery

Combustion engine

140

120

100

80

60

40

20

T [°C]

fiAMBIENT TEMPERATURE

Simulation results for a vehicle in the NEDC

Calculations show that these kinds ofheating systems can actually absorb justas much power as driving itself and cantherefore reduce the range by up to 50percent. Porsche Engineering has devel -oped new and innovative approaches torelieve customers from the need to pickwhether to drive or freeze. Integratedauxiliary heating systems based on re-newable fuels or combinations of heatpumps, latent heat-storage units and air-and water-based auxiliary heaters can bedesigned and built according to the vehi-cle model and the requirements profile.

The Porsche engineers and designers al-ways have the whole vehicle in mind,which means that secondary methodsare also taken into account and testedfor efficiency and feasibility in the op-timization of thermal management.The use of innovative (insulation) ma-terials and designs to insulate the inte-rior and components can therefore leadto targeted results in order to promoteheat transfer or specifically insulate it.

Conclusion: challenges and solutions

Electrically powered vehicles no longerrequire conventional cooling as in com-


bustion engines, or they require it only toa limited extent. With the lack of enginewaste heat and the option of poweringaccessories using the combustion en -g ine, new solutions must be developedfrom the viewpoint of both thermal andenergy requirements.

This leads to complex thermal mana ge -ment systems at various temperaturelevels for cooling the battery, the elec-tric motor, the power electronics andany range extender. Climate control inthe vehicle interior is also becomingmore complex.

The specialized engineers at PorscheEngineering meet these challenges withsolid thermal management experienceand expertise from classic sports cardesign and construction as well as ex-perience from electromobility projects.

Using all available development toolsfrom simulation to calculation, from con -ventional component testing in the tes t -ing facility to the testing of the ent irevehicle on the test track, Porsche Engi-neering develops components, mod ulesand entire systems for the thermal pro-tection and optimization of vehicles andproducts of all kinds.

battery in the Boxster E, as it can beseen above. Based on the analysis re-sults from the thermal model describedabove, the cooling plate was designedgeometrically and optimized using com -putational fluid dynamics (CFD). The re-sult is a highly efficient and lightweightheat exchanger, optimally tailored andadapted to the battery pack, with lowpressure losses, high cooling perfor-mance and a very even distribution oftemperature.

Vehicle interior climate control

Another challenge in the design of elec-trically powered vehicles is the provi-sion of heating and cooling systems forpassenger comfort, as well as consider -ing aspects relevant to safety such askeeping the windows free of condensa-tion or ice (defrost function). The climatecontrol systems customers are familiarwith and expect from conventional vehi -c les require an energy input of up to 3 kWon hot and humid days, and up to 7 kWin the cold winter months for heating thevehicle. As there is no waste heat fromthe combustion engine, this energy re-quirement must be met by the tractionbattery, e.g. using a high-voltage PTCauxiliary heater.


Boxster E battery cooling plate

Temperature

Electromobility Hybrid mountain bike and Seabob

37

Mobility goes electric – the Porsche Hybrid RS mountain bikeand the Seabob


Whether it is the Panamera S Hybrid, the918 Spyder, the Cayenne S Hybrid orthe 918 RSR, the integration of electricpower in Porsche vehicles with conven-tional combustion engines is advancingall the time. Porsche Engineering hasalso demonstrated that electric energycan power more efficient mobility on asmaller scale. In the Hybrid RS mountainbike prototype and the series watercraftSeabob, batteries provide the energyfor new levels of performance.

At the beginning of 2010, the idea wasborn to emphasize the hybrid expertiseof Porsche by developing a hybrid moun-tain bike and presenting it alongsidethe Porsche Cayenne S Hybrid. Within a

very short period of time, engineers atPorsche Engineering developed fullyfunctioning prototypes of hybrid moun-tain bikes and unveiled them at the pre-sentation of the Cayenne S Hybrid.

As early as 2009, Porsche Engineeringhad already been developing “pedelecs”(Pedal Electric Cycles) as part of a re -s earch study. Unlike conventional bicy -c les, pedelecs feature an electric motorto propel the bicycle with electric powerin addition to muscle power through pe d -al ing. With a pedelec, the electric energycan be used only if the person on themountain bike is also pedaling at thesame time. Recuperation of energy in apedelec is achieved the same way as in

a car, using the brake system. This meansthat energy produced when cycling canbe recovered during braking and storedtemporarily in the pedelec battery. Thisenergy is then available again to the sys -tem to propel the mountain bike.

The characteristics of the prototype bikedeveloped for the Cayenne S Hybrid pre-sentation are those typical of a Porschevehicle: the high-performance HybridRS mountain bike is lightweight and yetsuitable for rough terrain (full suspensionmountain bike). The styling of the bikealso played an important role during de-velopment. Special emphasis was placedon creating a sporty look with high-qualitycomponents in typical Porsche design.



use sensors to recognize the angle of thebrake lever and transmit this informationfor a completely smooth recuperation.

The motor assistance can be set todifferent levels and is controlled via aniPhone, which is mounted securely on ahandlebar bracket. The app has beenprogrammed by Porsche Engineeringand not only controls the electric motor,but also displays the current flow ofenergy and the charge state of the bat-tery. The iPhone communicates with thecontrol electronics, which were alsodeveloped by Porsche Engineering, via

In good company: the hybrid bike was unveiled together with the Porsche Cayenne S Hybrid

wireless LAN. If desired, the app can sim -ulate cycling uphill for training purp -oses by specifying an electric brakingtorque.

When the Cayenne S Hybrid was pre -sen ted in Leipzig, national and interna-tional journalists were very impressedwith the Hybrid RS mountain bike’sdiverse functions and enthused abouthow much fun it was to ride. PorscheEngineering has successfully transferredhybridi zation to two wheels. The onlydownside of the Hybrid RS: the mountainbike is a concept bike and not plannedfor series production.

One series product that has been mak -ing waves in the water for some time isthe sports watercraft Seabob, whichhas an electric drive for environmentallyfriendly and speedy fun on and belowthe water. Porsche Engineering has madea decisive contribution to increasing thepropulsion efficiency of this unusual re-creational craft.

It can be easily steered and controlled,simply by shifting the body weight. Thespeed of the craft is controlled with acontrol grip. The Seabob weighs around60 kilograms (132 lbs.) and has an elec-tric jet drive rated at seven hp (5.2 kW).It can reach speeds of between 15 and20 km/h (9 and 12 mph) and can diveto a depth of 40 meters (130 ft.). Forsafety reasons, the series producedSeabob is currently pre-set to allow div -ing depths of 2.5 meters (8.2 ft.) orless. Users wishing to dive deeper canunlock its deep diving capabilities byentering a PIN code. Propulsion is prod -uced using the jetstream principle.

Porsche Engineering developed an app which vi su alises among other things the energy flows

The frame of the mountain bike alsoadvertises its hybrid nature.

The Porsche Hybrid RS mountain bikehas a lightweight carbon-fiber frame,which results in a total weight of lessthan 16 kilograms (35 lbs.). The electrichub motor with direct drive can contrib -ute up to 450 watts to the rear wheel,without additional gearing. The energyis provided by a lithium manganese bat-tery with 161 Wh, located on the framein place of the water bottle.

The drive is regulated by torque sens -ing: as soon as the pedals are turned,the motor delivers additional torqueand in this way boosts the pure musclepower of the cyclist. This allows evenvery steep inclines to be ascended withease and greater speeds to be reached.The electric power lasts for a distanceof around 50 kilometers or 31 miles.When the brakes are applied (for exam-ple when going downhill), the drive motorbecomes a generator and produces elec-tric braking torque. The patented brakes

The powerful rotating impeller sucks inwater and pushes it out through a jetchannel at high pressure. The CayagoSeabob is impressive not only thanks toits driving pleasure and striking look:hard work in development also produc -ed cutting-edge technology. The engi-neers at Porsche Engineering developedno less than three electronic compo-nents for the patented watercraft: thebattery manager, the motor control sys -tem and the operating sys tem withgraphical display.

With a capacity of 40 ampere-hours perfour-volt cell, the battery manager moni-tors the function of the lithium-ion bat -teries integrated into the craft. These bat -teries are also used in aerospace technol -ogy applications. In order to protect thelithium-ion batteries from damage, aspe c ial electronic system was developedto monitor the voltage in each individ -ual cell. The battery manager also con-trols the power monitoring system andthe power cutoff for charging and dis -charging the battery. Furthermore, nu-merous sensors monitor the operatingtemperature. Using cell balancing, the

Battery-operated watersports fun on and below the water: the Seabob

electronics ensures an equal voltage inall cells. This prevents the voltages ofthe series-connected batteries fromdrifting apart.

The Seabob’s electric motor is complet e -ly emissions-free and almost silent. Itscontrol system works with a digital signalprocessor (DSP) and creates a sinusoidalthree-phase current from the battery volt -age. Phase currents of up to 200 am -peres are generated from the DC link volt -age of 60 volts at maximum. The poweroutput stage even allows for up to 250amperes. The motor has a rated powerup to 7.5 kw but can be over loaded totwice this figure if necessary. The rotorposition is measured by three Hall effectsensors. The drive consists of a high-torque synchronous drive. Using the verylatest technology and despite its surpris -ingly compact size, the motor achieves

the optimum torque with an exceptionaleffi ciency level of over 96 per cent. Dur -ing an endurance test over more than10,000 operating hours at maximumoutput, there was neither a fault nor adecrease in power in the motor.

The illuminated LCD panel clearly and leg -ibly shows all important motor electro-nics technical data. This includes the cur-rent driving power, remaining operatingtime and the charge state of the battery.The rider is also given important informa-tion about diving depth and water tem-perature on this display. Finally, an inte-grated infrared interface allows softwareupdates to be uploaded and diagnosticdata to be read out, while important pro -gramming functions can be conven ientlycontrolled using the LCD panel.

The result is a sports watercraft that canbe intuitively operated, that has an intelli-gent battery and motor control system,and that guarantees endless fun in thewater. That is not all: Porsche Engineeringis currently working together with Caya-go to create a significantly lighter modelthat promises to be even more fun.

So whether it is a hybrid bike or theSea bob, Porsche Engineering brings itsexpertise and experience in the area ofelectromobility to a variety of differentapplications – even if they have little todo with automotive engineering.



Electromobility Panamera S Hybrid


Panamera S Hybrid: the Porsche Gran Turismo sets a new benchmark for its class

Without sacrificing sportiness or ele-gance, the new hybrid model combinesa total power output of 380 hp (279kW) with a best case fuel consumptionof only 6.8 l/100 km (41.54 mpg imp.)based on the NEDC (New European Driv -ing Cycle). This is equal to CO2 emis-sions of only 159 g/km. The PanameraS Hybrid is therefore not only the mosteconomical Porsche ever, it is also farahead of all other full hybrid series vehi-

cles in the luxury class in terms of fuelconsumption and CO2 emissions.

These incredible statistics were achiev -ed with Michelin all-season tires witheven lower rolling resistance, develop -ed especially for the Panamera andavailable as an option. Even with stan-dard tires the fuel consumption of thenew Porsche hybrid model is only 7.1l/100 km (39.79 mpg imp.) based on

the NEDC – the equivalent of 167 g/kmof CO2 – an exceptionally low level neverachieved before in this class.

Only the Panamera S Hybrid can “sail” up to 165 km/h

The Panamera S Hybrid sets new stan-dards, both in terms of classic perfor-mance and when measured against hy-brid vehicle characteristics. Capable ofaccelerating from zero to 100 km/h(62 mph) in just 6.0 seconds, the Pana -mera S Hybrid can reach a top speedof 270 km/h (168 mph). The range inpurely electric mode is approximatelytwo kilometers (1.24 miles), while elec-

The Porsche Panamera S Hybrid marks a new chapter

in Porsche Intelligent Performance and continues the

success story of the four door Gran Turismo.



torque capacity of up to 300 Nm (221ftlb.) from a standing start to power fullypropel the car forward. The maximumoutput of both of the drives, 380 hp,is achieved at 5,500 rpm, while thecombined torque of 580 Nm (428 ftlb.)is reached at only 1,000 rpm, whichguarantees a powerful and impressivethrottle res ponse.

Like the Porsche Cayenne S Hybrid, thePanamera S Hybrid also has an E-Powerbutton in the center console, which canbe activated to expand the range inwhich the vehicle can be driven underpurely electric power. The activation isshown firstly via an LED on the buttonand secondly, the word “E-Power” ap-pears in blue, illuminated text on theinstrument cluster. In E-Power mode, theaccelerator pedal characteristic curve ischanged so that pressure on the accel -erator pedal is converted much moremoderately. The combustion engine istherefore prevented from starting auto-matically too early when more power isrequired.

tric driving is possible at speeds of upto 85 km/h (53 mph), depending onthe situation. The Porsche hybrid drivealso enables even more energy-savingpotential to be unlocked at high speedsby using the so-called “sailing” func-tion on highways and rural roads. Thissystem is the first and only one of itskind in the world. At speeds of up to165 km/h (103 mph) (Cayenne S Hyb rid:156 km/h (97 mph)) when no power isbeing delivered from the combustionengine, it is disengaged from the drive-train and switched off.

A great team: the compressor andthe electric machine

The Panamera S Hybrid is powered bythe same engine combination that hasalready proven itself in the Cayenne SHybrid: a three-liter V6 compressor en-gine with 333 hp (245 kW) is responsi-ble for the main power, supported by anelectric machine with an output of 47 hp(34 kW). Both machines are capable ofpowering the Panamera S Hybrid either

alone or in combination. The electricmachine also operates both as a gen -erator and a starter. Together with thedecoupler, it makes up the compact hy -b rid module located between the trans-mission and the combustion engine. Theelectric motor is connected to a nickel-metal hydride battery (NiMh), where theelectrical energy recovered from drivingand braking is stored. Power transmis-sion is handled by the familiar eight-speed Tiptronic S, fitted as standard inthe Cayenne models, with a wide spreadof ratios.

The driver can unleash the maximumpower of the Panamera S Hybrid byusing the so-called “booster” function.When this is activated, the combustionengine’s and the electric machine’s drivetorque are combined and reinforce eachother. This is another major advan tageof the Porsche hybrid design. While thecombustion engine reaches its maxi-mum torque of 440 Nm (325 ftlb.) be - t ween 3,000 rpm and 5,200 rpm, theelec tric machine can make use of its full

The Porsche hybriddrive allows for thecombustion engine tobe disconnected andswitched off when nodrive power is required

Porsche exclusive: the parallel fullhybrid, compact and powerful

Instead of using a power-branched hy -b rid drive, Porsche went for a parallel fullhybrid. There were numerous reasonsfor this decision. Unlike other hybrid sys -tems, which offer particular advantagesfor stop-and-go city driving, the systemdeveloped by Porsche also provides theadditional option to “sail” in the Pana -mera S Hybrid, with the combustion en-gine switched off and at speeds of upto 165 km/h (103 mph). The parallel fullhybrid model also allows the kind ofacce leration and elas ticity typical of aPorsche without the so-called rubberband-effect of power-branched hybridsystems. The concept therefore fits per-fectly with the Porsche philosophy: ex-ceptional driving performance combin -ed with the highest level of efficiency.Another advantage is the comparativelysmall amount of space required: at only147.5 millimeters long, the full hybridmodule is particularly compact. It is po-

sitioned between the combustion eng -ine and the transmission, and consistsprimarily of the ring-shaped synchro-nous motor and a decoupler on the sideconnected to the com bustion engine. Inthis way, the power flux and characteris -tics are the same as a conventional drive.Additionally, the Porsche hybrid does notadd much extra weight. The Panamera SHybrid weighs only 1,980 kilograms(4,361 lbs.) when empty and is thereforequite trim for its class. It can also take aload of up to 505 kilograms (1,112 lbs.).

Impressive equipment

The range of standard equipment forthe Panamera S Hybrid is even widerthan that of the already extensive stan-dard equipment of the Panamera S witheight-cylinder engine. For example, thehybrid model is fitted as standard withthe adaptive air suspension includingthe adaptive shock-absorber system withPASM, with Servotronic and a rear wiper.The new Gran Turismo also features theinnovative display design from the Cay-enne S Hybrid that provides the driverwith all the relevant information aboutthe vehicle’s specific hybrid driving sta-tus. The performance of both powersources as well as all of the relevant sta-tistics related to the hybrid drive are dis -played to the driver on the TFT displayin the instrument cluster. The driver cansee the charge state of the traction bat-tery and the energy flows, illustrated byan arrow in the direction of flow, in realtime on the display. The Panamera SHyb rid creates totally novel highlightsin the luxury segment – from sporty toenvironmentally friendly – and thus un-derlines the strategic importance ofPorsche Intelligent Performance.Porsche Communication Management (PCM) shows the hybrid drive in operation and energy flows in detail

In line with the Porsche philosophy: exceptional driving performance combined with maximum efficiency



Porsche Engineeringdriving identities

www.porsche-engineering.com

Summing up 80 years of efficient engineering performance:

no resource wasted, no dream untapped.

Porsche Consulting heartily congratulates Porsche Engineering on its 80th Anniversary –

and looks forward to further successful teamwork.

www.porsche-consulting.com

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