a request for proposal supply of lithium … of lithium-ion batteries for isro leo missions ......

Information Proprietary to Battery Division, ISAC, ISRO

A REQUEST FOR PROPOSAL

SUPPLY OF LITHIUM-ION BATTERIES

FOR

ISRO LEO MISSIONS

March 2015

PREPARED BY

INDIAN SPACE RESEARCH ORGANISATION

DEPARTMENT OF SPACE

GOVERNMENT OF INDIA

BANGALORE - 560 017

INDIA

RESTRICTED Doc No: ISAC/PSG/BD/544/Li-Ion/ RFP/LEO Mission

Information Proprietary to Battery Division, ISAC, ISRO

THIS PAGE IS

INTENTIONALLY

LEFT BLANK

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TABLE OF CONTENTS Content ................................................................................... page # SECTION I ..................................................................................... 8

1.0 Preamble .................................................................. 8 SECTION II .................................................................................... 8

2.0 Specifications ............................................................ 8

2.1 General Requirements ................................................ 9

2.1.1 Heritage .......................................................... 10

2.1.2 Cell built in safety features ................................ 10

2.2 Mission requirements ................................................ 10

2.3 Cells Specifications ................................................... 11

2.3.1 Cell type ......................................................... 11

2.3.2 Cell LAT (Lot Acceptance) tests .......................... 12

2.3.3 Screening and matching of cells ......................... 12

2.4 Battery specifications ................................................ 13

2.4.1 Overall specifications ........................................ 13

2.4.1.1 Identification and Product Marking ...................... 13

2.4.1.2 Visual Inspection .............................................. 13

2.4.1.3 Conformance to drawing ................................... 13

2.4.1.4 Dimensions and mass ....................................... 13

2.4.2 Electrical requirements...................................... 14

2.4.2.1 Capacity performance at ambient ....................... 14

2.4.2.2 Capacity performance at different temperatures ... 14

2.4.2.3 Charge and Discharge rate capability .................. 14

2.4.2.4 Self discharge .................................................. 14

2.4.2.5 Output impedance ............................................ 14

2.4.2.6 Insulation resistance ......................................... 15

2.4.2.7 Bonding resistance ........................................... 15

2.4.2.8 Corona discharge ............................................. 15

2.4.3 Electrical Interface requirements ........................ 15

2.4.3.1 Electrical isolation ............................................. 15

2.4.3.2 Connectors ...................................................... 15

2.4.3.3 Wiring and derating .......................................... 15

2.4.3.4 General ........................................................... 16

2.4.4 Thermal requirement ........................................ 16

2.4.4.1 General ........................................................... 16

2.4.4.2 Temperature monitoring ................................... 17

2.4.4.3 Temperature requirements ................................ 17

2.4.4.4 Temperature range requirements ....................... 17

2.4.5 Mechanical Requirements .................................. 18

2.4.5.1 General ........................................................... 18

2.4.5.2 Vibration ......................................................... 18

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2.4.5.3 Mounting Interface ........................................... 19 SECTION III ................................................................................ 20

3.0 Management, Reporting, Documentation, and Reviews .. 20

3.1 Management and Reporting ....................................... 20

3.2 Documentation ........................................................ 20

3.3 Cell and Battery Design Reviews and Meetings ............. 20

3.4 Pre-shipment Review ................................................ 20 SECTION IV ................................................................................. 21

4.0 Quality Assurance and reliability ................................. 21

4.1 Quality Assurance Plan/Manual .................................. 21

4.2 Performance evaluation of the Vendor ......................... 21

4.3 Mandatory Inspection Points ...................................... 21

4.4 Reliability ................................................................ 22

4.4.1 Electrical, Electronic, and Electromechanical Parts Stress Analysis .............................................................. 22

4.4.2 Failure Report and Analysis ................................ 22

4.5 Workmanship .......................................................... 22

4.6 Safety Requirements ................................................ 22

4.7 Outgassing and Corrosion.......................................... 23

4.8 Traceability and Input Material Inspection.................... 23

4.9 Storage .................................................................. 23

4.10 Handling, Packaging and Shipping ...................... 23 SECTION V ................................................................................... 25

5.0 Initial acceptance test plan ........................................ 25

5.1 Acceptance test plan ................................................ 25 SECTION VI ................................................................................. 28

6.0 Deliverables ............................................................ 28

6.1 Documents .............................................................. 28

6.1.1 Before Design Review ....................................... 28

6.1.2 At MRR ........................................................... 28

6.1.3 At TRR ............................................................ 28

6.1.4 Before delivery of batteries ................................ 28

6.1.5 With the batteries ............................................ 29

6.2 Deliverable Hardware ............................................... 29 ANNEXURE - I .............................................................................. 30

Built-in safety features of cells ........................................ 30 ANNEXURE – II ............................................................................ 31

EIDs for Connectors ....................................................... 31 ANNEXURE – III .......................................................................... 32

1.0 Test plan for acceptance of Lithium-Ion batteries. ......... 32

2.0 Scope ..................................................................... 32

3.0 Test Sequence ......................................................... 32

3.1 Tolerances .............................................................. 32

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3.2 Standard test conditions ........................................... 33

4.0 Cell tests ................................................................. 33

4.1 Battery Conformance tests ........................................ 33

4.1.1 Identification and Product Marking ...................... 33

4.1.2 Electrical and Mechanical ICD verification ............ 34

4.1.3 Initial Functional checks .................................... 34

4.1.4 Visual Inspection As per Visual Inspection .......... 34

4.1.5 Dimensions and mass As per 2.4.1.4 ................ 34

4.1.6 Bonding Resistance .......................................... 34

4.1.7 Isolation.......................................................... 35

4.1.8 Thermistor calibration ....................................... 35

4.2 Battery electrical tests .............................................. 36

4.2.1 Standard capacity & Capacity Test at 20°C .......... 36

4.2.1.1 Standard capacity measurement at 20°C ............. 36

(Qual and acceptance) ................................................... 36

4.2.1.2 Capacity Test at 20°C(Qual and acceptance) ........ 36

4.2.2 Capacity Test at 30°C(Qual and acceptance) ........ 37

4.2.3 Capacity Test at 10°C (Qual and acceptance) ....... 37

4.2.4 Capacity Test at 0°C (Qual) ............................... 38

4.2.5 Capacity Test at 40°C (Qual) ............................. 38

4.2.6 Charge Retention Test(Qual) ............................. 39

4.2.7 Internal Resistance (Qual and acceptance) .......... 39

4.3 Environmental tests .................................................. 40

4.3.1 Mechanical tests ............................................... 40

4.3.1.1 Vibration Test .................................................. 40

4.3.1.2 Repeat tests [Post environmental tests] .............. 41

4.3.2 Thermal tests .................................................. 42

4.3.2.1 Passive Thermal cycling test .............................. 42

4.3.2.2 Thermal vacuum tests ...................................... 42

4.3.2.3 Standard Capacity measurement at 20°C [Post environmental tests] ...................................................... 43

4.3.2.4 Charge Retention Test [Post environmental tests] 43

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Abbreviations Aho: Ampere Hour Out

AIT: Assembly Integration and Test.

ATP: Acceptance Test Procedure.

BOL: Beginning Of Life.

CC: Constant Current

C.G.: Centre of Gravity

CIDL: Configuration Item Data List

DCL: Declared component list

DML: Declared Material List

DOD: Depth Of Discharge

DPA: Destructive Physical Analysis

DPL: Declared Parts List

EGSE: Electrical Ground Service Equipment

EID: Electrical Interface Detail

EIDP: End Item Data Package

EOC: End Of Charge

EOD: End Of Discharge

EOL: End Of Life

ESA: European Space agency

ESD: Electro Static Devices

FE: Finite Elements

FM: Flight Model

FMECA: Failure Modes, Effects and Criticality Analysis

GEO: Geostationary Earth Orbit

GRP: Glass Reinforced Plastic

GSFC: Goddard Space Flight Centre

ICD: Interface Control Document

ISRO: Indian Space Research Organisation

LAT: Lot Acceptance Test

LEO: Low Earth Orbit

MCD: Manufacture and Control Document

M.I.: Moment Of Inertia

MIP: Mandatory Inspection Point

MS: Measurement Specialities

NA: Not Applicable

NASA: National Aeronautics and Space Administration

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NC: Non - Conformance

NCR: Non-Conformance Report

PO: Purchase order

PFM: Proto flight model

PSR : Pre-Shipment Review

QA : Quality Assurance

QM: Qualification Model

RGA : Residual Gas Analysis

S/c : Spacecraft

SoC: State of Charge

TBD : To Be Decided

VOQ: Verification Of Quality

Who: Watt Hour Out

YSI : Yellow Springs Incorporation

Definitions (i) Standard Capacity: (C)

Capacity obtained when charged at C/10 rate to a maximum of 42V and

discharged at C/10 rate to 25V at 20°C, shall be called the Standard

capacity of the battery. This Capacity measured at/during ATP, shall

be taken as reference for all quality control measures.

(ii) Depth of discharge (DOD)

DOD is defined as the ratio of capacity discharged to the nameplate capacity.

(iii) Cell lot

It is defined as the cells produced from the same batch of source materials used to build the cell plates.

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SECTION I 1.0 Preamble

The Indian space research organization (ISRO) is responsible for developing and

maintaining GEO, LEO and scientific satellites. ISRO has planned domestic

satellites, scheduled to be launched by indigenously developed launch vehicle, in

the years to come. In these satellites, the power system is configured to provide

100% payload power support during eclipse and sunlit using Li-ion batteries.

ISRO proposes to use two 48 Ah nameplate capacity Lithium Ion batteries of

10S-nP (where n is number of parallel string) configuration, (meeting all the

specifications provided in this document) in domestic LEO spacecraft supporting

the eclipse load as per mission requirements specified in section 2.2. The

batteries shall have a design life of > 5 years in LEO orbit. ISRO intends to buy

three batteries (1(QM/PFM*) + 1 FM+ 1 FM spare) for domestic programs. The

delivery of the batteries is envisaged within a year of PO/export licence

whichever is later (To+12month). Separate quotations for (1) fabrication alone

with minimum tests as per Table 10 (section V) and (2) for both fabrication &

full-fledged testing as per Table 12 (section V) may be submitted by the Vendor.

Quotation for both the cases mentioned above needs to include (a) quote for 2

batteries as well as (b) 1 additional but spare battery (i.e. 2+1 batteries).

It is very important for our evaluation of your offer that your proposal includes

sufficient technical data in form, fit and function. Special features referenced to a

standard battery design aimed at improving the life and performance of the

batteries shall be given due consideration.

The quantities and the specifications in this document may be modified by ISRO

on any ground, during technical negotiations, before the finalization of the

contract.

ISRO reserves the right to witness the Qualification / Acceptance tests and to

review the progress of work at various milestones of the program. If any test is

to be carried out at a place other than the supplier's premises, the supplier shall

make appropriate arrangements for the participation of the ISRO nominee(s).

*To be decided after analyzing the heritage of cell/battery.

SECTION II 2.0 Specifications

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The space quality Lithium-Ion batteries shall be assembled using hermetically

sealed, SONY make 18650 HC/HCM standard cells or equivalent with good

heritage in space programs. The batteries shall have 10S–nP configuration to

deliver a minimum capacity of 45 Ah at C/2 rate discharge at 20°C. The batteries

shall have lightweight construction and shall be designed for use as per mission

requirements specified in section 1.2.2.

The cells shall be screened and acceptance tested as per VENDOR Technology

procedures based on ESA Hi-Rel standard specifications for similar electronic

components like electrolytic capacitors.

The following subsections provide the general requirements, details of mission

requirements, electrical, mechanical and thermal requirements, quality

assurance and reliability and life cycle requirements of the batteries.

2.1 General Requirements The base line design architecture shall be of “S-P” technology, using SONY

18650 HC/HCM cells or equivalent with highly uniform properties, closely

matched performance characteristics and built-in overcharge protection. The

configuration for the ISRO battery shall be 10S-nP i.e. 10 cells in series and n

cells in parallel.

Each battery shall have a minimum capacity of 45 Ah at C/2 discharge at 20°C

and a mid discharge voltage greater than 38V.

The battery design shall be such that no cell management electronics or bypass

switches are required to meet the mission requirements of ISRO LEO spacecraft

program

Note: vendor to carefully quote as two parts: (a) part one: - containing

only technical information and no costing information. It should have a

point to point compliance matrix & schedule information. (b) Part two:

- containing commercial information for slabs of 1-2 to 2-3 batteries.

Vendor shall make an MCD (manufacture and control document) including all

specifications, process and quality assurance / control parameters which shall be

submitted to ISRO for information to the extent defined below. Batteries with

similar design and proven flight history shall be supplied. The MCD shall include

the following:

1. The material list and process list for battery fabrication & testing. 2. Cell level process documents shall be available to ISRO for review. 3. Measurement and test equipment used and their calibration status. 4. Manufacturing flow diagram with internal process checks and QA check

points.

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5. Interface drawings shall be available to ISRO for on-site review. 6. Battery assembly procedure and check points shall be available to ISRO

for review. 7. Applicable documents for manufacture of batteries. 8. Unique travel cards for each battery, maintained during the process of

fabrication and testing, till delivery. 9. Duly completed formats for reporting Waivers, Non Conformances and

Results. Vendor shall make available all the above documents, for scrutiny by an

ISRO representative.

a) Vendor shall prepare a detailed plan and schedule for the fabrication and testing of batteries and it shall be submitted to ISRO for review. This plan shall be the basis for reporting the monthly progress.

b) Vendor shall ship the batteries by Air/ship after conforming to UN standards regarding Air-Shipment.

2.1.1 Heritage The proposed cell should have been flown in several LEO satellites. The proposed cell should have been well characterised on ground for various operating GEO and LEO mission profiles specifically DOD, cycle, and no of years. Vendor shall provide the list of LEO and GEO missions for which batteries have either been supplied or under manufacture.

2.1.2 Cell built in safety features Proposed cell should have built in safety features like overcharge protection, short circuit protection and other fault safe mechanisms as mentioned in annexure –I. 2.2 Mission requirements The design adequacy of 10S–nP configured Lithium-Ion battery to meet the mission requirements of the spacecraft program to be checked and confirmed.

S/N Performance parameter Value

1 Total spacecraft load (Eclipse +payload power to be supported by battery)

335W for 35mins (eclipse)and 400W for 10mins(sunlit) typical or 20%DoD (max)

2 Orbit Altitude (Km) 630

3 Orbital Inclination ( deg) 98

4 Orbit duration (minutes) 97

5 Mission life (years) >5

6 Number of charge/discharge cycles 15 per day

7 Total number of charge/discharge cycles over mission life

>30,000

9 Number of batteries per spacecraft 1 10 Battery operating voltage range(V) 30 to 42

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11 Minimum capacity margin at EOL 20% of nameplate capacity 12 Storage life

10 – 30°C

0 – 10°C

15 – 30°C

6 Months (transportation & Acceptance testing) 5 to 7 years (Cold Storage, low SOC) 6 Months (AIT operations)

13 Design temperature range of operation

10 – 30C

14 EODV at EOL > 34 V* 15 End of charge voltage of battery BOL: 40 V**

EOL: 42 V** 16 Charge current (Max.) C/4 *** 17 Discharge Current (Max.) C/2 *** 18 DOD on nameplate capacity 20% 19 No. of 100% DOD cycles during ATP

tests and AIT operations 20

20 No. of Temperature sensors 3 21 Number of string failure to be

accounted 1(minimum)

*Vendor to specify EODV at EOL. **Vendor shall provide the charge and discharge voltage profile over life. ***Vendor shall provide the allowed charge and discharge current for entire life.

Table 1: Mission Requirements

2.3 Cells Specifications 2.3.1 Cell type

The cells selected to fabricate the batteries shall meet the following performance requirements:

Parameter value

Cell type Sony 18650 HC/HCM or equivalent

Cell Dimensions 18mm Diameter (typical): __max*

65 mm length (typical): __max*

Cell mass 41grams (typical): _____ max*

Maximum cell voltage 4.2V

Minimum cell voltage 2.5V

Name plate cell capacity 1.5 Ah (typical): _____ max*

*Vendor is required to specify the actual maximum value.

Table 2: Cell Specifications

The cells selected for batteries shall have sufficient heritage in space and ground life tests should have been conducted to assure that the design meet the mission requirements provided in section 2.2. If already qualified battery configuration exists with the vendor, it will be preferred.

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Vendor shall select the cells not older than 3years.

2.3.2 Cell LAT (Lot Acceptance) tests

The cells selected (not older than 3years) for battery fabrication shall be part of the batch which is subjected to stringent standard LAT tests as specified in ANNEXURE – II.

The LAT tests shall include DPA, environmental, abuse/safety and endurance subgroups to detect any variations in the batch of cells. Each cell used in the space batteries shall be subjected to a screening test to achieve high reliability.

Vendor shall provide details of the LAT test results for tests done on the cells. The test procedures shall be made available to ISRO for review. The test results shall be submitted to ISRO for information.

2.3.3 Screening and matching of cells

Each cell selected for battery fabrication, shall be screened for the following aspects:

visual inspection at 10X magnification Mass and dimensional check Capacity measurement EOC impedance measurement EOD impedance measurement Self discharge rate measurement

The capacity, EOC impedance, EOD impedance and self discharge of every cell shall be measured to high precision. The measured cell properties shall be fully traceable to battery assembly through a unique BAR code on each cell. The charge-discharge characteristics of the cells shall be supplied to ISRO. The cells selected to form strings shall be closely matched in capacity, EOC resistance, EOD resistance, self discharge rate and voltage characteristics before fabrication of batteries. Vendor shall provide the screening and matching test procedure and test results to ISRO as a part of MRR and EIDP.

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2.4 Battery specifications 2.4.1 Overall specifications 2.4.1.1 Identification and Product Marking

Each battery shall be uniquely identified by marking battery type, batch number, serial number, energy, Vendor’s name and date of manufacture on a suitable surface of the battery so as to be visible. The battery batch number and serial number shall be located on the appropriate sidewall. The marking process and marking material shall not in any way affect the battery performance.

2.4.1.2 Visual Inspection

Each battery shall be examined for Quality of workmanship and absence of manufacturing defects Finish of welded and soldered joints Absence of Mechanical damages, scratches and other defects Identification markings as stated in 2.4.1.1 Presence of all deliverable parts.

2.4.1.3 Conformance to drawing Vendor shall generate mechanical, electrical and general assembly CAD drawings with Bill of Materials and parts and submit to ISRO for review / approval. Each battery shall be checked for conformance to the above drawings.

2.4.1.4 Dimensions and mass The battery dimensions and mass shall be as small as possible. All surface non uniformities shall be kept to a minimum.

Parameter value

Length (Max) 360mm (max), ___*

Width (max) (including connectors) 300mm (max), ___*

Height (max) 160 mm (max), ___*

Mass (max) 18 kg (max), ___* Flatness clearance (max) 0.1mm (max), ___*

* Vendor is required to specify the realisable maximum value ≤above specs.

Table 3: Battery Dimensions & mass

After finalization of contract, no increase in dimensions is possible. Vendor shall provide battery Interface Control Drawing giving mass, dimension and C.G. values. There shall be no change in the mounting interface and electrical interface drawings after approval.

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2.4.2 Electrical requirements

2.4.2.1 Capacity performance at ambient A standard capacity measurement at C/10 charge to 42 V and discharged at C/10 rate to 25V, at 20°C, shall be taken as reference for quality control measure. The battery shall have a minimum capacity of 45 Ah at C/2 rate at 20°C, when delivered by Vendor.

2.4.2.2 Capacity performance at different temperatures The battery when charged at C/10 rate to 42V and discharged at C/2 rate to 25V shall meet the following capacity requirements at different temperatures:

Temperature

Minimum guaranteed discharge capacity between 42V (EOCV*) to

25V (EODV*) (Ah)

40°C > 45 30°C > 45 20°C > 45 10°C > 42 0°C > 41

Table 4: Battery Capacity at different Temperatures

* Vendor is required to specify EOCV and EODV.

2.4.2.3 Charge and Discharge rate capability

4 The battery shall be capable of being charged at C/4 rate or higher* in the temperature range of 10°C to 30°C without any performance degradation or deterioration.

5 The battery shall be capable of supporting discharge current peaks of C rate for short bursts of 1 second for special operations at minimum of 50% state of charge, without any performance degradation or deterioration.

* Vendor is required to specify maximum charge rate allowed.

2.4.2.4 Self discharge The fully charged battery when kept open for 30 days at 20°C shall deliver more than 95% of its stored energy. The battery leakage current due to self-discharge shall be less than 4 mA.

2.4.2.5 Output impedance

The output impedance of a fully charged battery measured at the electrical power interface shall be less than 50*milliohms in the range 20Hz to 10 kHz at 20°C for 48Ah battery. *Vendor to specify the procedure and expected value.

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2.4.2.6 Insulation resistance The battery when tested for insulation resistance between the battery ground point with the battery positive, battery negative and the thermistor lines shall have a resistance > 100Mohms at 500V.

2.4.2.7 Bonding resistance

The battery when tested for bonding resistance between side walls to end walls, bonding stud to mounting feet and connector shells to end walls, shall have a resistance less than 5 milliohms. One bonding stud shall be provided on the battery structure for grounding purposes.

2.4.2.8 Corona discharge

The battery shall not exhibit voltage transient (corona discharge) during transition from ambient to vacuum.

2.4.3 Electrical Interface requirements 2.4.3.1 Electrical isolation

The voltage monitoring lines and the power lines shall be isolated from the aluminium interface structure of the module with a resistance of greater of 100 Mega ohms at 500V. An additional level of electrical isolation shall be ensured by wrapping a 50 µm Kapton sheet around the outer cells in each brick to prevent possible shorting to the support structure. A physical gap between the cells shall be ensured and adhesive shall be used to bond cells into the GRP support plates. The cell interconnections shall be conformally coated and covered with a layer of Kapton film.

2.4.3.2 Connectors

The battery shall be provided with Circular connectors for power and monitor and shall be of space qualified. These connectors shall have removable crimp contacts meeting ESA specifications ESA/SCC 3401 001. All connectors on the battery shall be of socket type.

2.4.3.3 Wiring and derating

The cells in the battery shall be arranged in series connection to form strings of cells and the strings are connected in parallel to form the battery (10S-nP). The cells shall be connected into series strings using nickel interconnects, made from nickel strip material, which shall be spot welded to each cell. The nickel strips used for the interconnects shall meet

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the standard specifications such as ASME SB 160 specifications. The cell interconnections shall be conformally coated. The cells and wiring shall be arranged to minimize loops to reduce the dynamic magnetic fields. All harness wires shall be derated in accordance with the ESA specification ECSS–Q–30–11A. The following shall be the connector wiring detail for each battery i. Power and Monitor Connector Positive wires for power, derated to 48 A (total):20AWG wires Negative wires for power, derated 48 A (total): 20AWG wires

(Spec 55 wires shall be used for all power lines). Three wires each of 22 AWG for sense and monitoring battery positive

voltage (One of the battery voltage monitoring lines, shall be provided with a protection resistor of RLR 20C1002, 0.5W, 10 kohm).

Three wires each of 22 AWG for sense and monitoring battery negative voltage.

Three live and Three return lines for thermistors: 24 AWG wires. One wire of 22 AWG for bonding stud. Any change proposed in the wires or schematic shall be mutually discussed and finalised. While routing wires positive and negative wires are to be isolated from each other.

2.4.3.4 General The cell-harnessing scheme shall use good design so as to minimize the magnetic moment generated by currents in the battery itself. Bonding straps shall be used to link all the sidewalls electrically. One bonding stud to be provided on each battery.

2.4.4 Thermal requirement 2.4.4.1 General

The battery shall be designed to conduct the heat generated in the cells efficiently to the spacecraft structure through the feet of the battery unit. A thermal plate can be bonded to the cell support plate to improve conductivity. The design shall thermally isolate the cells from the battery mechanical structure to optimize the battery performance. The thermal resistance between the cells and the battery deck shall be minimized.

Thermal analysis shall be performed by Vendor to show that the batteries can operate in a vacuum environment at operational temperature limits as seen at the base-plate. Vendor shall perform transient thermal analysis for the eclipse period to verify that maximum gradient within the battery does not exceed the specified limits as per section 2.4.4.3. Thermal analysis shall be made for both extremes of temperatures at BOL and EOL conditions at 100C and 300C at base independently. The thermal analysis report shall be delivered to ISRO.

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Vendor needs to specify thermal properties of cell as well as battery and

provide thermal model of both.

2.4.4.2 Temperature monitoring

Each battery shall be fitted with three standard 10k (make/ model: YSI 44908 / Measurement Specialities 44908) thermistors, meeting NASA GSFC S 311–P–18/07 specifications, to monitor the battery temperature at three different locations. The location of the thermistors shall be so as to indicate the maximum temperature on the battery and the maximum gradient within the battery. The location of thermistors shall be mutually discussed and finalised. Each thermistor on the battery shall be calibrated with respect to a standard calibrated thermocouple/thermistor in the temperature range of –20°C to +60°C. The thermistor calibration results as required by the above specification shall be provided to ISRO.

2.4.4.3 Temperature requirements

The battery module thermal design should meet the following temperature requirements during various conditions of charge and discharge: Maximum gradient across the strings: <10°C (between parallel strings) Maximum gradient along the string: <5°C (within a series string of cells)

Vendor shall inform where the temperatures shall be measured and the method to demonstrate gradients. A thermistor at the middle shall be taken as reference thermistor for any electrical test.

2.4.4.4 Temperature range requirements

The battery shall meet the following temperature range requirements under various conditions:

Conditions Temperature range Storage temperature range -10°C to +25°C* Qualification temp range 0°C to +40°C Acceptance temp range +10°C to +30°C Operating temp range +10°C to +30°C

Table 5: Battery Temperature ranges

*Vendor to specify extreme temperature range and duration of storage at extreme temperature. Battery specified performance should be met over the operating temperature range when tested after storage as above.

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2.4.5 Mechanical Requirements 2.4.5.1 General

The battery should have sufficient stiffness to meet the vibration requirements. The cells shall be bonded into the recesses in the cell support plates to ensure thermal contact and electrical isolation from each other and from the S/C structure. The structural load path from the cells shall be through the cell support plates to the sidewalls and finally to the S/C through the battery feet. The battery shall have the first natural frequency, with rigid interface, above 125Hz. The fully charged battery should withstand the vibration levels (as in Table 6 to Table 9) without any performance degradation. Use of accelerometer mounting interface plates shall be discussed with ISRO. One of the flight battery shall undergo vibrations to Qualification level while others to acceptance level vibrations. Quasi-static loads specified for battery is 25 g out of plane and 20 g in-plane. If the battery is already qualified to these levels only acceptance level vibration will be done for flight battery. Mechanical Analysis needs to be carried out by the vendor. FE model in MSC/NASTRAN format (optional) Mechanical analysis report shall be delivered to ISRO.

2.4.5.2 Vibration A fully charged battery shall be subjected to the following vibration levels without any performance degradation. One battery shall undergo Qualification Level or proto flight and the other(s) battery shall be subjected to acceptance level vibration test.

RANDOM VIBRATION: X, Y & Z axes

Frequency (Hz)PSD (g2/Hz)

Qualification Level Acceptance Level

20 – 100 + 3 dB/octave + 3 dB/octave

100 - 700 0.1 0.044

700 - 2000 - 3 dB/octave - 3 dB/octave

Overall rms 11.8 g 7.9 g

Duration 2 minute 1 minute

Table 6: Random Vibration levels: X,Y & Z axes

PFM(Proto flight module):Qualification level with acceptance duration.

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Table 7: Sine vibration levels: X & Y axes

SINE VIBRATION: Z axis(OUT OF PLANE)

Frequency (Hz) Amplitude


5 – 20 12.4 mm 8.3 mm

20 – 70 20 g 13.3 g

70 – 100 15 g 10 g

Sweep Rate 2 octave/minute 4 octave/minute

Table 8: Sine Vibration Levels: Z axis

Shock level (For all three axis)

Frequency (Hz) SRS

100-600 15 dB/octave

600-5000 1000g

No of pulse 2

Vendor to specify the shock level upto 1000g

Table 9: Shock

The levels are at the base of the battery. Note: Without degradation means the results of repeat tests shall match with the results obtained prior to mechanical tests after taking into account the measurement errors and usual behavior experienced during other battery test programs.

2.4.5.3 Mounting Interface The battery shall have suitable number of �6.2 mounting holes compatible to M6 bolt. The base plate feet, with adequate thickness, shall provide the structural and thermal interface with the spacecraft. Vendor to specify the bolt type, torque value and thermal contact area.

Battery handling requirements: Suitable battery handling provision to be provided. Base plate at the bottom to be provided with handling provision.

SINE VIBRATION: X & Y axes(IN-PLANE)



5 – 20 9.3 mm 6.2 mm

20 – 70 15 g 10 g

70 – 100 8 g 5.3 g

Sweep Rate 2 octave/minute 4 octave /minute

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SECTION III 3.0 Management, Reporting, Documentation, and Reviews 3.1 Management and Reporting

Vendor shall designate a single individual who will be given full responsibility and authority to manage and administer all phases of the work specified by the contract and ensure that all objectives are accomplished within schedule and cost constraints. This individual shall be the focal point for contact and communication with ISRO for all aspects of the battery contract.

3.2 Documentation

Vendor shall ensure the generation and delivery of all documentation as called for in the Contract. This is the QA documentation for the build standard, non conformance reporting, testing and progress reporting. Data of all the tests is needed to be provided in MS Excel format.

3.3 Cell and Battery Design Reviews and Meetings

Vendor shall organize and present a detailed MRR to an ISRO Review Team at the Vendor’s facility on a date mutually agreed upon or as defined in the contract. This review shall demonstrate readiness to start fabrication of the Batteries. This review shall cover programmatic, test and verification, and quality assurance aspects associated with the cell and battery manufacture. This review shall also provide an opportunity to review and approve cell matching data, cell and battery MCD before the start of battery fabrication.

Vendor shall provide required deliverable data to ISRO at least 10 working days in advance of the MRR.

A MRR Report shall be prepared following the review, which as a minimum shall contain meeting notice, agenda, minutes of the review meeting described above and response to all recommendations and action items generated during the review.

3.4 Pre-shipment Review

Vendor shall hold a pre-shipment Review, prior to shipment of batteries. The Batteries shall be conditionally accepted at the Vendors facility after completion of testing, PSR and close out of all open action items. The final acceptance of battery will be after receipt and inspection and capacity check / acceptance testing at ISRO (if not done at Vendor’s site).

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SECTION IV

4.0 Quality Assurance and reliability 4.1 Quality Assurance Plan/Manual

Vendor shall implement a Quality Management System that meets the requirements of International Standards Organization (ISO). ISRO shall be notified of any changes to the QA program. Vendor shall submit detail quality assurance plan for realizing the product. The plan shall include minimum of the following: Evidence for all parts, materials and processes used for realizing the

battery shall have proven heritage for space application. Declared parts and Material List (DML) and Declared Process List

(DPL) as per ECSS-Q-70. Incoming acceptance test plan for the parts /materials proposed to

be used in the battery. Cell selection/matching and Lot acceptance plan for the proposed cell

lot. Quality assurance plan for the subcontracted items including the cell. Process identification Document including assembly procedure with

relevant process flow / inspection points and criteria of acceptance. Safety assurance plan for the battery. Design verification and Test and evaluation plan for the battery. Non conformance management plan. Review process. Certification process. Qualification plan and results for similar design. Risk assessment and management plan Abuse test reports Failure reports, if any(on board or ground) Any other standards applicable.

4.2 Performance evaluation of the Vendor The work activities and operations, documents, records, equipment etc of Vendor, subcontractors, and suppliers are subject to evaluation, review, survey, and inspection by an ISRO representative.

4.3 Mandatory Inspection Points

Vendor shall identify key inspection points as part of in-process inspection of the battery. Vendor and/or ISRO representative will perform inspection at the following Mandatory Inspection Points (MIPs) listed below: Inspect 100% solder /crimps. Inspect 100% conformal coating, stacking, and potting. Rework Inspection. Pre-closure Inspection. PSR Inspection / Data Review.

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4.4 Reliability

All materials used in the manufacture of the battery shall be of space grade and of proven usage in space environment. The battery shall be designed to have very high reliability when used in space environment for the duration and type of mission specified in section 2.2 All batteries delivered shall be identical in all respects. They shall be of uniform quality and manufactured out of materials procured from same Vendors. All parts, materials and processes shall have been approved and previously used by Vendor in other space missions. Vendor shall specify the maximum allowed storage period & required storage conditions for mission requirement. Vendor shall provide reliability analysis document.

4.4.1 Electrical, Electronic, and Electromechanical Parts Stress Analysis

Vendor shall provide necessary documentation. Vendor shall provide evidence either by test or by analysis, that the battery designed, shall meet the mission requirement as per section 2.2.

4.4.2 Failure Report and Analysis Vendor shall provide the procedures and general practices that should be followed for handling failure and non conformance at various stages of manufacture and testing. Any failure during fabrication or testing shall be documented and reported to ISRO within 24 hours. Vendor shall provide, as part of the monthly report, a list of all failure reports, action for which are open and a separate list of the failure reports, action for which are closed, during the month. For each reported failure or non-conformance, there shall be a report that documents the investigation and engineering analysis needed to determine the cause and corrective actions to disposition the failure. Reports shall be submitted to ISRO for review and approval of the disposition.

4.5 Workmanship The batteries shall be in good shape and condition with good surface finish and devoid of scratches, dents, deposits etc. Any sharp edges and burrs shall be eliminated.

4.6 Safety Requirements

The batteries shall be designed to be non-hazardous associated with the launching of the spacecraft in an atmosphere containing hydrogen of concentration exceeding 1% by volume. The battery design shall conform to safety requirements as applicable to Lithium-Ion batteries such as overcharge, over discharge, short circuit, mechanical damage, high temperature etc.

Necessary launch pad safety certificate shall be issued by Vendor.

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4.7 Outgassing and Corrosion

The materials used external to the cell and internal to the battery shall have the following properties: Total Mass Loss when tested at 125°C for 24 hours in a vacuum of 10-6

torr, shall be less than 1%. The Volatile Condensable Material in a vacuum of 10-6 torr and 125°C

shall be less than 0.1% [Ref: method A of ESA-PSS-01-702]. All external materials used in the manufacture of batteries shall be non-

corrosive or shall be subjected to corrosion resistive treatment, resistant to fungus growth under conditions of 90% relative humidity at 20°C.

The following materials are consequently prohibited, unless adequately coated to limit evaporation: Mercury, Cadmium, pure Tin, unauthorized plastics or elastomeric materials. Deviation, if any, in this regard shall be communicated to ISRO and approval taken before Design Review.

4.8 Traceability and Input Material Inspection

All materials used in the manufacture of batteries shall be traceable to the input lot, whose characteristics shall have been measured, checked for conformity and recorded at the time of input material inspection. All material inspection reports shall be made available to the user when required. A log of all procedures, in-process checks, test conditions and results shall be maintained for all the batteries. This logbook shall be made available for scrutiny by ISRO. The logbook shall also include recent calibration certificates of all equipment used. Vendor shall provide reference numbers of all applicable documents in the manufacturing and Control Document and all of them shall be available for inspection by ISRO.

All logbooks and manufacturing records, which are not deliverable, shall be maintained by Vendor for 10 years from the date of delivery of the hardware for traceability and any other diagnostic purpose.

4.9 Storage

The batteries shall meet all the functional requirements stated above, after storage at room temperature or below (-10°C to room temperature) in a discharged and open circuit condition for long durations (minimum 5 years). Vendor to specify allowed storage duration and conditions.

4.10 Handling, Packaging and Shipping

The batteries shall be suitably packed and shipped as per standard procedure followed by Vendor. Each battery shall be mounted on a handling plate* and packaged in an insulated material to avoid any electrical short circuit. Required numbers of fused connector savers (fuse harness) shall accompany each battery. The batteries shall be packed in suitable containers, meeting UN norms, to withstand environmental stresses and

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handling loads during transport by truck, aircraft or ship. The container shall be equipped with suitable gadgets to indicate the humidity level, the maximum and minimum temperatures, and the shock and vibration levels experienced by the batteries during transit. During transportation by Sea or Air, the battery temperature should not exceed 30°C. Vendor to specify minimum SOC (state of charge) during Air/ship/road transportation.

*handling plate shall be compatible for thermovacuum test.

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SECTION V 5.0 Initial acceptance test plan

Vendor shall deliver the batteries after completing initial acceptance tests as defined in Table 10.

TEST DESCRIPTION TESTS ON ALL

BATTERIES 1. BATTERY CONFORMANCE TESTS

a. Identification and Product Marking

b. Electrical and Mechanical interface detail verification

c. Initial Functional checks d. Visual Inspection e. Dimension and Mass checks f. Bonding Resistance checks g. Isolation checks

X

2. Charge retention test @20 0C X 3. Standard capacity test [20°C] X 4. Review of results X

Table 10: BATTERY INITIAL ACCEPTANCE

5.1 Acceptance test plan

Acceptance testing of batteries shall be performed as per procedure given in ANNEXURE – III to ensure conformity with all the specifications given in SECTION II. Fig.1 gives the plan of activities. Table 11 gives the overall battery test plan and Table 12 gives the battery test matrix.

After receipt of batteries at ISRO, each battery shall be subjected to mandatory tests given in Table 10 to check health of battery after transportation. In case of failure of any battery, detailed analysis shall be performed to determine the cause of failure and reviewed by Vendor and ISRO for acceptance or rejection and re-export. The final acceptance of the batteries will be after successful completion of all tests. In case of failure of any battery, detailed analysis shall be performed to determine the cause of failure and reviewed by Vendor and ISRO. If the failure is due to a generic manufacturing / design defect then all the batteries of that lot shall be rejected and re-exported to Vendor as-is- where-is basis. Vendor shall re-design and fabricate three more flight model batteries entirely at its own cost. If the failure is diagnosed as not due to generic defect and is due to any equipment or human errors, the test shall be repeated on the same battery.

Vendor shall supply 100 cells, along with cell test data in MS Excel format, to ISRO. Vendor shall ensure that all cells of this lot shall conform to the

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same quality, maintain same process parameters and use same material as that of flight batteries.

ISRO reserves the right to witness and review the progress of work at various milestones of the programme. If any test is to be carried out at a place other than the supplier's premises, the supplier shall make appropriate arrangements for the participation of the ISRO nominee(s).

Fig. 1: PLAN OF ACTIVITIES

SL No.

TEST DESCRIPTION

TO BE DONE ON

TO BE DONE AS PER

RESPONSIBILITIES

1 tests on cells cell lot Vendor Procedure Vendor 2 Pre- Acceptance

tests on batteries

As per Table 10 Vendor Procedure Vendor

3 acceptance tests

on batteries

All FM batteries (with QM/PFM tests on one

battery)

AS PER TEST MATRIX GIVEN IN

Table 12 Vendor/ISRO

4 Final acceptance tests on batteries

All FM batteries (with QM/PFM tests on one

battery)

As per Table 10 ISRO(if SL No:3

is at vendor site)

Table 11: BATTERY TEST PLAN

AWARD OF CONTRACT

DESIGN REVIEW

MANUFACTURE OF BATTERIES and INITIAL TESTS

PRE-SHIPMENT REVIEW

RECEIPT OF BATTERIES AT ISRO

PROCUREMENT OF CELLS

MATCHING OF CELLS

TESTING OF BATTERIES AT ISRO

ACCEPTANCE OF BATTERIES, AFTER SUCCESSFUL COMPLETION OF

TESTS

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Note: Plan and schedule of activities for tests to be conducted by Vendor, shall be intimated to ISRO at least 30 days prior to start of the test. All tests shall be carried out in accordance with approved test procedures. Unless otherwise stated, all tests required shall be performed at standard atmospheric pressure, at a temperature of 20°C±3°C and a relative humidity of 30% to 60%.

Table 12: BATTERY TEST MATRIX

TEST DESCRIPTION Reference to test Procedure in

Annexure - III

Acceptance tests on Flight

batteries

Qualification tests on Qual Model battery

1. BATTERY CONFORMANCE TESTS a. Identification and Product Marking b. Electrical and Mechanical Interface

detail verification c. Initial Functional checks d. Visual Inspection e. Dimension and Mass f. Bonding Resistance g. Isolation h. Passive Thermal cycling i. Thermistor calibration

4.1 4.1.1 4.1.2

4.1.3 4.1.4 4.1.5 4.1.6 4.1.7

4.3.2.1 4.1.8

X

X

2. a. Standard capacity test [20°C] b. Capacity test at 20°C

4.2.1.1 4.2.1.2

X X

X X

3. Capacity test at 30°C 4.2.2 X X 4. Capacity test at 10°C 4.2.3 X X 5. Capacity test at 0°C 4.2.4 - X 6. Capacity test at 40°C 4.2.5 - X 7. Charge Retention test 4.2.6 X X 8. **Internal resistance test at 20°C 4.2.7 X X 9. Vibration test

Sine and Random Vibration Test -QM Shock test – QM Random to Acceptance level -FM

4.3.1.1

- - X

X X -

10. Repeat tests [Post Mechanical Tests] 4.3.1.2 X X 11. Visual Inspection 4.1.4 X X 12. Isolation measurement 4.1.7 X X 13. Capacity test [20°C] 4.2.1.2 X X 14. **Internal resistance test [20°C] 4.2.7 X X 15. Thermal Vacuum test 4.3.2.2 X X 16. Charge Retention test 4.2.6 X X 17. Standard capacity test [20°C] 4.2.1.1 X X 18. Review of results X ** Internal Resistance test and Capacity Test at 20°C may be combined together. For PFM test matrix will be same as ACCEPTACE except vibration.

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SECTION VI 6.0 Deliverables 6.1 Documents

Vendor shall provide the documents as detailed in following sections.

6.1.1 Before Design Review a) Detailed battery design document giving all battery design

parameters, with justification, assuring design adequacy in complying with all the specifications. Mechanical, Thermal & Electrical design documents shall be provided to ISRO. It should include all relevant interface control drawings, properties of materials and acceptance criteria and details of battery performance characteristics.

b) List of components and materials proposed to be used, their specifications, quality levels, derating criteria and sources of supply.

c) Reliability analysis of the proposed battery. d) Standard Product assurance plan. e) Key inspection points and Mandatory inspection points during

manufacture of batteries f) Documentary proof of previous space history, if any. g) Test facilities and test instruments proposed to be used for the

program along with calibration data. h) Detailed schedule plan to meet the delivery schedule requirement

including risk assessment management. i) Process control document giving details of each process involved,

tolerances, in-process checks and acceptance criteria. j) Chart of the plan of activities for battery manufacture with

schedule. k) Complete plan of activities for cell LAT and battery initial acceptance

tests, as per Vendor procedure. l) Progress report for every month during the period of the contract.

It shall compare the progress against the planned activities and projected activities for the coming month.

m) If any document is proprietary, it has to be shown to ISRO. n) Process Identification Document (PID) to be provided to ISRO.

6.1.2 At MRR

a) Test Procedures, Acceptance criteria and results of LAT, screening and matching of cells to be made available for review.

b) Results, with failure criteria of LAT, screening & matching of cells to be provided to ISRO.

6.1.3 At TRR a) Test Procedures, Acceptance criteria and Test facilities and test

instruments of battery proposed to be used for the program along with calibration data to be made available.

6.1.4 Before delivery of batteries a) Certificate of technical conformity and statement of compliance to

the technical requirements in sections 2.2, 2.4.4.3 and 2.4.4.4. & 2.4.5 etc.

b) Traceability records of materials used during manufacture and testing of all batteries.

c) Results of all battery tests done at Vendors site [data pack]. d) NCRs and their dispositions. e) The updated results of accelerated and real time life cycle tests

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for both LEO and GEO cases for various DODs and storage.

6.1.5 With the batteries a) Complete data pack of each battery (EIDP) which shall include all b) Battery fabrication and test data and any other information necessary to

ensure the batteries meet the requirements of the contract. c) Certificate of conformance. d) All test certificates required for the safety during handling and launch. e) A user handbook including performance characteristics of battery at

different rates and temperatures, storage and maintenance procedures for short and long term storage, maintenance procedures during AIT and pre-launch activities (including method for final charging before launch) at ambient, safety precautions to be followed and procedures for transportation, handling and disposal.

f) Launch Safety Certificate Note:

i) The exact details of the nature and contents of the documents shall be agreed to between Vendor and ISRO at appropriate times.

ii) All documents shall be delivered sufficiently in advance for study and approval by ISRO. Suitable changes as required shall also be documented. A clear 10 days shall be provided to ISRO for its comments or approval before start of the activity indicated in the document.

iii) Any other document, certificate, data or hardware that may be necessary for efficient and safe use of the batteries during launch and in space environment. The format for such a certificate /document as required by ISRO.

6.2 Deliverable Hardware The delivery schedule for the batteries at ISRO shall be as follows:

S/N Item Description Quantity Delivery Date

1. 10S – nP, 48Ah Lithium-Ion battery (made with cells from same cell lot)

2/3 a)(1QM/PFM+1FM) b)(1QM/PFM+2FM)

To+9 months (If tested by ISRO). To+12 months (If tested by Vendor).

2. Lithium-Ion cells from the same screened batch of flight cells. 100

3. Data Package (Battery & cells) 1 set

4. Structural & Thermal Model of the battery

To = date of export lincence or date of purchase order whichever is later Table 13: Deliverables

Vendor shall draw and submit detailed schedules giving various elements such as, fabrication, testing and delivery etc., in broad conformity with the schedules given above.

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ANNEXURE - I Built-in safety features of cells

Safety Features

Overcharge Protection

Shut-down Separator

Controlled Cell Vent PTC

Cell feature Internal disconnect

PDF separator between anode and cathode

Burst disc

Positive Temperature Coefficient Polyswitch

Purpose Fail safe on severe overcharge

Fail safe at extreme high temperatures

Fail safe in the event of fire

Prevent damage to the cell in the event of short-circuit

Safety feature initiation

Cell overcharge by more than 100% (1500mAh above 4.2V)

High ambient temperature or very rapid overcharge

Pressure rise through external fire

Multi-second cell short circuit

Safety feature activation

Cell internal pressure

Cell internal temperature

Cell internal pressure

Temperature rise in PTC

Activation level* (typical)

>6 bar >80C >14 bar Short for over two seconds

Whether reversible?

Non-reversible

Non-reversible

Non-reversible Reversible

Effect* O/C failure O/C failure O/C failure Temporary high cell-impedance

Table 14: Built-in safety features of cells

*Vendor to specify and confirm.

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ANNEXURE – II The typical test for LAT can be as follows:

Selection of lot from BATCH (Measure electrical properties)

Build quality group- cell material inspection

Environmental group-vibration, thermal cycling, thermal vacuum

Electrical abuse group - over current, over charge, cell disconnect

Endurance group – accelerated life test, storage

DPA

Batch acceptance

Vendor to specify /provide the flow chart of test and no. of cells for LAT.

EIDs for Connectors Battery EID details to be discussed with ISRO and shall be finalised.

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ANNEXURE – III 1.0 Test plan for acceptance of Lithium-Ion batteries. 2.0 Scope

This annexure gives details of tests along with procedures to be followed and the relevant failure criteria, acceptance of the space quality Lithium-Ion batteries. These tests are conducted to ensure compliance with all the laid down specifications. One of the batteries will be subjected to qualification/PFM level tests and the others will undergo acceptance level tests.

3.0 Test Sequence The tests to be performed on the Lithium-Ion batteries are given in Table 11. These tests shall be performed in the exact sequence agreed to between Vendor and ISRO.

3.1 Tolerances

Unless stated otherwise, the following tolerances are applicable for test conditions and measurement accuracy for corresponding measurements. S/N Parameter Test

tolerance Measurement

accuracy

1. Temperature ± 3C ±1C

2. Relative humidity ± 5 % ± 1 %

3. Time (test duration) +5% ,

-0%

<1hr: ±1%, >1hr: 1min

4. Voltage (0 to 45V) ± 20 mV >5V: ±0.2%

5. Current or Power ± 2% ± 1%

6. Vibration: Random grms ±10% ± 1%

PSD (20 - 300Hz) ±1.5dB

PSD (300-2000Hz) ±3 dB

Sine vibration ±10% ± 1%

Frequency ± 2%

(Below 20 Hz) 0.5Hz

8. Acceleration ± 10% ± 1%

9 Vacuum Pressure >=0.1torr 5% 1%

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Vacuum pressure < 0.1torr ±50%

All meters, scales, thermometers and similar measuring and test equipment

used in conducting the tests shall be accurate to within 1% of the full-

scale value. All test apparatus shall be calibrated at suitable intervals

against standards whose calibration is traceable to the National Bureau of

Standards. Records of such calibration shall be available for inspection.

3.2 Standard test conditions

Unless stated otherwise, the standard test conditions are as follows:

1. Temperature 203oC

2. Pressure standard atmospheric pressure

3. Relative Humidity Less than 60%

4. Stabilization Temperature variation in 2 hours time is less than 2oC.

5. Discharge voltage All capacities are measured to a discharge voltage (EODV) of 25 V/battery.

6. Charge voltage All batteries to be charged to 42V at constant current of C/10 amps.

Table 15: Standard test conditions

Note: For each test the battery shall be soaked at the required temperature for at least 2 hours before start of test.

4.0 Cell tests

Vendor shall provide details of the LAT results with failure criteria, of tests done on the cells and shall maintain a complete record of the test results. The test procedures and results shall be made available to ISRO for review.

4.1 Battery Conformance tests 4.1.1 Identification and Product Marking The following should be verified by vendor: As per 2.4.1.1

Battery type, Cell batch number, Battery batch number, Serial number, Vendor’s name, energy Date of manufacture.

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4.1.2 Electrical and Mechanical ICD verification

As per 2.4.1.3.

4.1.3 Initial Functional checks The following shall be conducted to verify the integrity of thermistors, cells and connections as defined in the design. Measurement of full battery voltage Verification of thermistor operation Measurement of thermistor resistance Verification of EGSE monitoring inline protection resistors Any other measurements

These tests shall be performed at various stages throughout the test program and the results shall be documented in the test results supplied with the test procedure.

4.1.4 Visual Inspection As per Visual Inspection

Battery shall be subjected to visual examination for workmanship, finish, markings, damage and any other non-conformances. This test will be carried out in clean area. Battery shall be handled with clean gloves examined with a 10X magnifier. Acceptance Criteria:

1. Surface finish is good. 2. No Damage in welded or soldered joints. 3. Presence of battery identification number. 4. Surface not having bulges or dents. 5. No Corrosion marks on any part of the battery. 6. No Damage to connectors.

4.1.5 Dimensions and mass As per 2.4.1.4 The measurement of mass shall be determined to an accuracy of 0.01kg.

Acceptance Criteria: Battery mass lower than the limit specified: 18 kg L, B, H lower than 360 mm, 300 mm, 160 mm respectively.

4.1.6 Bonding Resistance

Bonding tests shall be performed to ensure the electrical continuity between the following locations [procedure to be supplied by Vendor]: Connector shells with end wall End wall with side wall, mid wall and end wall Bonding stud with middle foot of all end walls Bonding stud with middle foot of all side walls

Acceptance Criteria: Bonding resistance< 5m

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4.1.7 Isolation [Procedure to be given by Vendor] Tests shall be performed to ensure isolation between the following: All positive and negative battery power & monitor lines from the bonding stud. Bonding stud to thermistors. Thermistors to power lines. Acceptance Criteria: Resistance > 100 M at 500V.

4.1.8 Thermistor calibration

This test shall be performed before the initial capacity check. Calibrate battery thermistors at 0°C, +20°C and + 30°C as per following procedure: a) Mount calibrated thermocouples close to the thermistors. b) Place the battery in a hot and cold chamber. c) Allow the chamber to stabilize at set temperature. d) Compare temperatures read by each of the thermistors to corresponding

thermocouples. e) Repeat steps (c) and (d) for other two temperatures. Acceptance criteria: TC & Thermistors are adjacent to each other: Temperatures measured by thermistors as compared to those measured by calibrated thermocouples differ by less than 1°C.

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4.2 Battery electrical tests

4.2.1 Standard capacity & Capacity Test at 20°C

4.2.1.1 Standard capacity measurement at 20°C

(Qual and acceptance) The following procedure shall be adopted to perform the standard capacity measurement. Stabilize the battery at T=20°C, or rest 1 hour if test is at the same temperature as the previous cycle. a) If the battery OCV is > 30V, Discharge the battery at C/10 rate, until the

battery voltage reaches 25V* typical (EODV). b) Charge at C/10 rate, until battery reaches the set upper limit of 42V*

typical (EOCV). c) Measure and record battery voltage, current and temperature every 30

minutes and also time to reach EOC V. d) Rest 10 minutes. e) Discharge at C/10 rate, until battery reaches 25V. f) Measure and record battery voltage, current and temperature every 15

minutes and also time to reach EOD V. g) Compute the charge and discharge capacities and the charge

efficiencies. h) Compute the charge and discharge energy and the energy efficiencies. i) Compute the average voltages (=Wh/Ah) in both charge and

discharge. j) Measure the end of charge resistance (EOCr) and end of discharge

resistance (EODr). *Vendor to specify the actual values.

Acceptance criteria: The capacity obtained is greater than 45 Ah.

4.2.1.2 Capacity Test at 20°C(Qual and acceptance)

Stabilize the battery at T=20°C, or rest 1 hour if test is at the same temperature as the previous cycle. a) If the battery OCV is > 30V, Discharge the battery at C/10 rate, until the




minutes and also time to reach EOD V. g) After 1 hour of discharge, increase the discharge rate to 1C (total) for

0.5 seconds and record the battery voltage drop and current. Calculate dynamic impendence.

h) Compute the charge and discharge capacities and the charge efficiencies.

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i) Compute the charge and discharge energy and the energy efficiencies. j) Compute the average voltages (=Wh/Ah) in both charge and

discharge. k) Measure the end of charge resistance (EOCr) and end of discharge

resistance (EODr).

*Vendor to specify the actual values. Acceptance criteria: The capacity obtained is greater than 45 Ah.

4.2.2 Capacity Test at 30°C(Qual and acceptance)

Stabilize the battery at T=30°C, or rest 1 hour if test is at the same temperature as the previous cycle.

a) If the battery OCV is > 30V, Discharge the battery at C/10 rate, until

the battery voltage reaches 25V* typical (EODV). b) Charge at C/10 rate, until battery reaches the set upper limit of 42V*






i) Compute the charge and discharge energy and the energy efficiencies. j) Compute the average voltages (=Wh/Ah) in both charge and

discharge. k) Measure the end of charge resistance (EOCr) and end of discharge

resistance (EODr). *Vendor to specify the actual values.

Acceptance criteria: The capacity obtained is greater than 45 Ah.

4.2.3 Capacity Test at 10°C (Qual and acceptance)

Stabilize the battery at T=10°C, or rest 1 hour if test is at the same temperature as the previous cycle.

a) If the battery OCV is > 30V, Discharge the battery at C/10 rate, until the



minutes and also time to reach EOC V. d) Rest 10 minutes. e) Discharge at C/2 rate, until battery reaches 25V.

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f) Measure and record battery voltage, current and temperature every 15 minutes and also time to reach EOD V.

g) After 1 hour of discharge, increase the discharge rate to 1C (total) for 0.5 seconds and record the battery voltage drop and current. Calculate dynamic impendence.


i) Compute the charge and discharge energy and the energy efficiency. j) Compute the average voltages (=Wh/Ah) in both charge and discharge. k) Measure the end of charge resistance (EOCr) and end of discharge

resistance (EODr). *Vendor to specify the actual values. Acceptance criteria: The capacity obtained is greater than 42 Ah.

4.2.4 Capacity Test at 0°C (Qual) Stabilize the battery at T=0°C, or rest 1 hour if test is at the same temperature as the previous cycle.

a) If the battery OCV is > 30V, Discharge the battery at C/10 rate, until the







i) Compute the charge and discharge energy and the energy efficiency. j) Compute the average voltages (=Wh/Ah) in both charge and discharge. k) Measure the end of charge resistance (EOCr) and end of discharge


4.2.5 Capacity Test at 40°C (Qual) Stabilize the battery at T=40°C, or rest 1 hour if test is at the same temperature as the previous cycle.

l) If the battery OCV is > 30V, Discharge the battery at C/10 rate, until the

battery voltage reaches 25V* typical (EODV). m) Charge at C/10 rate, until battery reaches the set upper limit of 42V*

typical (EOCV). n) Measure and record battery voltage, current and temperature every 30

minutes and also time to reach EOC V. o) Rest 10 minutes. p) Discharge at C/2 rate, until battery reaches 25V. q) Measure and record battery voltage, current and temperature every 15

minutes and also time to reach EOD V.

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r) After 1 hour of discharge, increase the discharge rate to 1C (total) for 0.5 seconds and record the battery voltage drop and current. Calculate dynamic impendence.

s) Compute the charge and discharge capacities and the charge efficiencies.

t) Compute the charge and discharge energy and the energy efficiency. u) Compute the average voltages (=Wh/Ah) in both charge and discharge. v) Measure the end of charge resistance (EOCr) and end of discharge


4.2.6 Charge Retention Test(Qual) This test can be performed independently or combined with a capacity measurement at the same temperature as follows: a) Stabilize the battery at 20±2°C. b) Discharge the battery at C/10 rate, until the battery voltage reaches

25V. c) Charge at C/3 up to 35V. d) Rest for 20 hours. e) Measure open circuit voltage V1. f) Rest for an additional 72 hours minimum. g) Measure open circuit voltage V2. h) Calculate the difference between voltages V1 and V2 for the duration

corresponding to 72 hours. Acceptance criteria: The difference in voltage between V1 and V2 (<140mV) corresponding to a leakage current less than 4 mA.

4.2.7 Internal Resistance (Qual and acceptance)

This test is done at room temperature (202oC).

a) Stabilize the battery at 20±2°C b) Discharge the battery at C/10 rate, until the battery voltage reaches

25V. c) Charge the battery at C/10 to 42V. d) Rest 1 hour [-0,+15 minutes]. e) Discharge the battery at C/2 for 1.2 hours. f) After 1.2 hours of discharge, increase the discharge rate to 1C (total)

for 30 secs and record the battery voltage drop and currents in the oscilloscope.

g) Reduce the discharge current to C/2 and continue discharge till each battery reaches 25V.

Acceptance Criteria: The battery internal resistance, calculated at the end of 1C rate, is less than 50 m. Note: This test may be done as a part of Capacity Test at 20°C.

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4.3 Environmental tests 4.3.1 Mechanical tests

One of the batteries shall undergo Qual level vibration/Proto flight level and the others shall undergo acceptance level random vibration as part of mechanical tests. For mechanical tests the battery shall be placed in a fixture, which will secure it firmly and ensure electrical insulation from the battery case to the ground. The mechanical tests shall be carried out at ambient temperature. The battery shall be charged at C/10 to 42V before the test. The battery shall be discharged at C/2 rate during vibration. Voltages and current shall be continuously recorded during that phase. In addition, the battery voltage shall be monitored on an oscilloscope to

observe for any voltage fluctuation. The required input levels shall be applied and controlled on the fixture

itself and not on the battery. At least one accelerometer shall be placed on the battery in the axis of

the test and shall be defined by Vendor and discussed with ISRO. Vendor to provide the levels for which the battery is successfully

qualified.

4.3.1.1 Vibration Test The battery shall undergo visual inspection and isolation checks prior to vibration tests as per section 4.1.4 and section 4.1.7. The battery shall be fully charged* and subjected to Qualification level/PFM or acceptance level random vibrations as specified in the table that follows. During vibration the battery shall be discharged at C/2 rate and variations in the battery voltage be monitored on an oscilloscope in the 50mV range. The vibration levels are as given below: *vendor to specify the charge voltage and SOC.

RANDOM VIBRATION: X, Y & Z axes

Frequency (Hz) PSD (g2/Hz)


20 – 100 + 3 dB/octave + 3 dB/octave

100 - 700 0.1 0.044

700 - 2000 - 3 dB/octave - 3 dB/octave

Overall grms 11.8 g 7.9 g

Duration 2 minutes 1 minutes

Table 16: Random Vibration levels: X, Y & Z axes

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SINE VIBRATION: X & Y axes(IN-PLANE)



5 – 20 9.3 mm 6.2 mm

20 – 70 15 g 10 g

70 – 100 8 g 5.3 g

Sweep Rate 2 octave/minute

PF 4 octave/minute

4 octave /minute

Table 17: Sine vibration levels: X & Y axes

SINE VIBRATION: Z axis(OUT OF PLANE)



5 – 20 12.7 mm 8.3 mm

20 – 70 20 g 13.3 g

70 – 100 15 g 10 g

Sweep Rate 2 octave/minute 4 octave/minute

Table 18: Sine Vibration Levels: Z axis

Failure Criteria: 1) Battery voltages have random variations of 300 mV or greater peak to

peak. 2) Battery showing visual damage. 3) Failure in performance of battery in repeat tests as in section Repeat

tests [Post environmental tests].

Note:

i) The levels are at the base of the battery. ii) The results of repeat tests shall match (within acceptable limits) with the

results obtained prior to mechanical tests, after taking into account the measurement errors and usual behavior experienced during other battery test programs.

4.3.1.2 Repeat tests [Post environmental tests] Subsequent to the random vibration, the following tests shall be repeated and the test results shall match with the results obtained prior to vibration tests on the batteries.

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Visual Inspection Refer section 4.1.4 of Annexure-III.

Isolation measurement Refer section 4.1.7 of Annexure-III

Capacity measurement at +20oC Refer section 4.2.1.2 of Annexure-III.

Internal resistance measurement at 20oC

Refer section 4.2.7 of Annexure-III.

4.3.2 Thermal tests

4.3.2.1 Passive Thermal cycling test

Keep the battery in hot & cold chamber and subject to 6 cycles of passive thermal condition between 0°C and 30°C. Dwell in each temperature for 2 hours. Refer thermal cycling profile given in Fig. 3.

4.3.2.2 Thermal vacuum tests

The battery shall undergo the following thermal vacuum tests: The battery shall be placed in thermal vacuum chamber plate. Additional thermistors / thermocouples shall be mounted at appropriate places to monitor the temperature gradients. The battery shall be loaded in the thermal vacuum chamber at 20°C and pressure reduced to 10 -6 torr.

The chamber temperature shall be maintained at 20°C. The battery shall be soaked at this temperature for 2 hours. The battery shall be discharged at C/10 rate, until the battery

voltage reaches 25.0V. The battery shall be charged at C/4 rate to 42.0V. The battery shall be discharged at C/4 rate for 35 minutes and

continue discharge cycle till 25V. Continuously monitored for mass nos. 62, 73, 75, 87, 89,

90,102,103 and 118 etc. or any other mass nos. specified by vendor for any leak using RGA.

Residual Gas Analysis shall be used to verify seal integrity of the cell in the battery under vacuum conditions.

Fig. 1: Passive thermal cycling profile

20°C

0°C

Time

30°C

Tem

pera

ture

2 hours dwell in each cycle

2 hours dwell in each cycle

2 hours in 100C

2 hours

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Failure Criteria: i. Any leak detected by RGA [leak rate to be defined by VENDOR]

ii. The end of discharge voltage of the battery at 60% DOD being less than

o 35 V at 20C Battery shall also meet the following criteria, if tested at the given

temperatures:

o 32 V at 0C. o 34 V at 10C. o 35 V at 30C

iii. Temperature gradient across strings >10°C

iv. Temperature gradient along a string >5°C

4.3.2.3 Standard Capacity measurement at 20°C [Post environmental

tests] As per section 4.2.1.1

4.3.2.4 Charge Retention Test [Post environmental tests]

As per section 4.2.1.1.