Organic Batteries Hiro Nishide

Waseda University, Tokyo, JapanGwangju Institute of Science and Technology, Korea

STYRIAN ACADEMY for Sustainable Energies Business Seminar, 6th July, 2011

Rechargeable/Secondary BatteryDefinition: A rechargeable battery is a cell for the generation of electrical energy in which the cell, after being discharged, is restored to its original charged condition reversibly by an electric current flowing in the direction opposite to the flow of current when the cell was discharged.

WASEDA Univ.

(Separator)(= Reducing Agent) (= Oxidizing Agent)

Reversible Conversion Cell for“Chemical Reaction Energy ⇄ Electrical Energy”

Cell Configuration

| Anode-active Material | Electrolyte | Cathode-active Material | ⊕

e- e- e- e-

Red2 → Ox2+ n2e-

AnodeOx1 + n1e- → Red1

CathodeOx2 + n2e- → Red2 Red1 → Ox1 + n1e-

Positive Electrode

Negative Electrode

WASEDA Univ.

Sustainable Battery

Energy devices designed to store and supply electric power, characterized by clean and reduced CO2 emission, effective utilization of alternative fuels, low environmental load, and safety, for a sustainable society. Organic batteries are inherently sustainable, owing to the environmentally benign fabrication and disposing processes, low toxicity and safety, based on the use of organic, resource-unlimited, and heavy metal-free materials.

Proposal of Li-Ion Battery by Prof. Goodenough

Prof. J. B. GoodenoughUniv. Texas at Austin

Li-Containing Transition Metal-Oxides as a Cathode-Active Material

Layered structure of LiMO2

• 4 V vs. Li/Li+(LixTiS2 : 2 V vs. Li/Li+)

• Reversible Intercalation of Li+

LiCoO2 Li1-xCoO2 + Li+x + e-

Li+

Concept of Rocking-Chair type Battery

e−

(-) (+)

e−ADischarge Charge

Charge

DischargeLi+

Graphite Anode (Intercalation)

Ethylene Carbonate Electrolytes(Safety Improvement)

Asahi Chemicals = Toshiba (Jp)Sony (Jp)

WASEDA Univ.

Global Production of Li-ion Batteries in 2009

0

2000

4000

6000

8000

1990 1995 2000 2005 2010

Wor

ldw

ide

Batte

ry M

arke

t (M

$/yr

)

Year

Pb

Ni-Cd

Ni-MH

Li-ion

JapanChina

Korea

Others

2009

JapanChina

Korea

Others2003

TOSHIBA

SONY

1993

Source: Calculated from data of Japanese Battery Industry Association (2010)

Li-Ion Battery

Lithium-ion Intercalation Materials

C6 + Li+ +e-→ C6Li

2LiCoO2 → 2Li0.5CoO2 + Li+ + e-[Cathode]

[Anode]

[Overall Reaction] 0.5C6Li + Li0.5CoO2 C3 + LiCoO2 : 100 mAh/gDischarging

Charging

C6Li → C6 + Li+ +e-

2Li0.5CoO2 + Li+ + e- → 2LiCoO2

[Cathode]

[Anode]

ChargingDischarging

e− e−

−

−

−

(Carbon)-Li Li1-xCoO2

Li＋

Li＋

Li＋

−

−

−

⊕

e− e−

⊕

LiCoO2

−

Carbon

Li＋

Li＋

−

−

Li＋

− Li＋ − Li＋−

Li＋Li＋

Li＋

WASEDA Univ.

Recycling of Used Li-ion Batteries in Japan

Primary battery: Landfill disposal = 57K ton/y

Secondary battery: Recycling = 1.4K ton/y

Used Li-ion batteries:

Recycling processCollection yield = 56% (64% for PC. and 80% for mobile phone)

Calcination Shredding

Sieving Melting Dissolving in acid Extraction of solvents

Used batteries Scrap steel and copper

Cobalt chlorideNickel chloride

Label:

25M ton/y

Chile

Australia

Argentina

China

Russia

Mineral Lithium

Calama

Santiago

Atacama

Argentina

Li Mineral Production

Bolivia

WASEDA Univ.

Conventional Primary and Secondary Batteries

Batteries Cathode Anode Voltage (V)Manganese oxide battery MnO2 Zn 1.5

Alkaline battery MnO2 Zn 1.5Silver oxide battery Ag2O Zn 1.6

Air battery O2 Zn 1.4Lead acid battery PbO2 Pb 2

Nickel-cadmium battery NiOOH Cd 1.2Nickel metal-hydride battery NiOOH MH(H) 1.2

Vanadium-lithium battery V2O5 Li-Al 3Lithium-ion battery LiCoO2 C 4

All of the conventional batteries are made up of HEAVY METALS !

WASEDA Univ.

・Given voltage is automatically governed by the coupling metal and metal oxide species.

・Limited metal resources / Tedious wasting processes / Non-safety such as ignition.

Previously Studied Electrode-Active Organic Materials

(1) Doping/dedoping of polyacetylene (in the early 80s)

CH=CH CH=C CH=CHx n-x

X- xe

+ xen

xn

< 0.1

WASEDA Univ.

(2) Doping/dedoping of polyaniline

・Low Energy-Density (limited doping degree)・Chemical Instability

・Inconstant Cell Voltage(3) Disulfide/thiol redox couple (in the latter 80s)

2 R-SH R-S-S-R 2H++- 2e

+ 2e・Slow Electrochemical Kinetics (bimolecular chemical reaction)・Nasty Oder

-2ne+2ne

Robust Organic Radicals

WASEDA Univ.

･sterically protected structure･resonanced structure

O

TEMPO

NO

O O

NO

N

OCH3CH3O

O

N

N

O

O

NO

NO

CCl

ClCl

Cl

Cl

Cl

ClCl

Cl

Cl

ClCl

ClCl

Cl

C

C N

S N

DPPH

N N

NO2

NO2

NO2 CN N

CH2

NN

N

OCH3CH3O

OCH3

C C C

O

WASEDA Univ.

Radical Precursors: Antioxidants & Light-stabilizers

Reductive removal of oxygen and radical contaminations, accompanied by their conversion into robust radical derivatives through the abstraction of hydrogen.

n

OH

OH OO

HN

N

HN

N

N N

N

HN

CH2 6 n

WASEDA Univ.

O-

p- and n-type Redox Couples of Organic Radicals

p-type: cathode-active

O N O N+ O

nitroxide radical oxoammonium cation

NO

-e-

+e-

NOO

n-type: anode-active

phenolate anion phenoxyl radical

-e-

+e-

O

Radical

Capacity (Mol. Wt.)(mAhg-1)

186 191 172 163 171 64 86 80

Electron Transfer Rate Const. k0 (cm s-1)

10-2 10-2 10-1 10-2 p: 10-1

n: 10-2 10-2 p: 10-2

n: 10-2 10-3

Electron ExchangeRate Constantkex (M-1s-1)

109 109 109 107 107 109 p: 107

n: 106 108

Durabilityhalf life

3 d 6 m 6 m 3 d 2 m 1 m 6 m 1 m

Molecular Designing of Radical Groups for High-Performance Charge Transport/Storage

NO

NO

N+NO O-

O

O

NNN N

N

OCH3

OCH3CH3O

NO N

O

K. Oyaizu, H. Nishide, in “Handbook of Radical Chemistry and Biology”, Ed. A. Studer, Wiley (2011)

Charge‐Transport and ‐Storage on Radical Polymer

NO

Charge Storage

Electron-Transfer (Charge-Transport) through Self Electron-Exchange Reaction

NO+

e‐

NONO

NONONONO

NO

e‐

e‐

NONO

NONONONONO+

e‐

e‐

e‐ NONO

NONONONO+

NO+

NO+NO+NO+NO+NO+

NO+NO+FullyCharged

NO+

NONO+

NO-e-+e-

Current Collector (Ex: ITO-PET with 100 m thickness)

Anode: n-Type radical polymer layer with thickness of 1－10 m

Electrolyte/Separator = Microporous film (Ex: polyethylene film with 200 nm pore and 20 m thickness) holding electrolyte (Ex: propylene carbonate or oligo ethyleneoxide containing ammonium salt)

Cathode: p-Type radical polymer layer with thickness of 1－10 m

Configuration of Radical Polymer Battery

WASEDA Univ.

Energy Diagram of p-Type and n-Type Radical Polymers as the Map of Redox Potentials vs Formula Weight-Based Capacities

Both current efficiency and Faraday efficiency are almost 100%.

0

0.2

0.4

0.6

0.8

1

1.2

0 50 100 150 200 250

Vol

tage

(V v

s. A

g/A

gCl)

Capacity (mAh/g)

○ = 10 C● = 50 C

2.53

3.54

4.5

Cel

l vol

tage

(V)

Cycle number0 1 2 998 9991000

2.0

1.6

1.2

0.8

0.4

0

Cel

l vol

tage

(V)

0 50 100 150 200 250 Capacity (mAh/g)

2.01.20.4

0 1 2 998 999 1000Cycle number

10 C60 C

N

CH3O OCH3

n

0 40 80 120

Redox Capacity / mAhg-1

OO

OO

NO

NO

n

N+NO O-

n

O

NO

O

n

NO

O

O n

Fe

n

O

NO

n

NO

O n

O

O

NO

n

O O

n

N+NO O-

n

NO

CF3

nN

OO

n

1.0

0.5

0

-0.5

-1.0

-1.5

E /V vs. Ag/AgCl

1.5

/eV

5.5

5.0

4.5

4.0

3.5

6.0

160

PTMA

PGSt

N N CH210 n

Redox capacity / mAhg-1

WASEDA Univ.

WASEDA Univ.

Charging curves Discharging curves

Current Rate Performance

Super rapid charging, High power discharge: Rapid electron-transfer in radical molecules / Amorphous morphology

Charging time: < 5 sec No voltage drop at any discharging rate

Unit C = Total capacity of the cell is (dis)charged for 1 hr.

Cel

l vol

tage

(V)

Discharge capacity (mAh/g)

0.5

1.0

0

-0.5

-1.0

-1.5

5 C 10 20 40 80120240360

0 20 40 60 80 100

Charging curves Discharging curves

3 C 2 C 1 C

100(%)

cf. Li-ion Battery

500

Cel

l vol

tage

(V)

Discharge capacity (mAh/g)

-0.5

0

360 C240120 80 40 20 10 5

0 20 40 60 80 100

1.0

0.5

Cycle number200 400 600 800 10000

20

40

60

80

100

Cycle number200 400 600 800 10000

20

40

60

80

100

Organic radicalbattery

Conventional Li-ion battery

WASEDA Univ.

Charge/Dischage Cycle-ability

Surprisingly long cycle life

Charge/discharging process without any structural change of the electrodeStability of the radical: shelf life of the battery > 5 years

e− e−

WASEDA Univ.

Polymer Electrode-Based Battery

Why a “polymer”?・Immobilization of the redox site in the electrode, to exclude elution of the redox site into the electrolyte and to avoid self-discharge.・The redox site with a very high density, for high capacity and high rate charge propagation.・Appropriate mobility of counter ions・Amorphous and plastisized, to avoid deformation and heat-generation during charging and discharging.・Molding of electrode・Flexibility・Wet fabrication process

(+) (-)

e− e−

Anode Cathode

Charging

(+) (-)

Red2

Red2

Red2

Red2

Red2

Red1

Red1

Red1

Red1

Red1

Ox1

Ox1

Ox1

Ox1

Ox1

Ox2

Ox2

Ox2

Ox2

Ox2

Red2

Red2

Red2

Ox1

Ox1

Ox1

Ox2

Ox2

Ox2

Red1

Red1

Red1

Charge Propagation in the Radical Polymer Layer Equilibrated with an Electrolyte Solution

WASEDA Univ.

Current collector

Polymer layer

e-NO・NO・ NO+NO+e‐ NO・NO+e‐e‐ e‐e‐

Reversible Electron-transfer of Organic Robust / Electroactive Radicals vs Doping of Organic Molecules

WASEDA Univ.

-e-

+e-

-e-

+e-

n-Doped

Openshell

OrganicMolecule

Closedshell

p-Doped

Openshell

-e-

+e-

-e-

+e-

Anion

Closedshell

RobustRadical

Openshell

Cation

Closedshell

SOMO

LUMO

HOMO

LUMO

HOMO

Large Flux of Charge Mediated through Radical PolymerThe redox gradient-driven charge transport by the enhanced

exchange reaction among the densely populated radical redox sites accomplishes substantial flux of electron with very-high current density of 0.1–100 mA/cm2 .

Thin Layer of the Radical Polymer Equilibrated with Electrolyte

10-8~-10 (cm2/s) × 10-2~-3 (mol/cm3) ÷ 10-4~-5 (cm) × 96485 (C/mol)≈ 10-4~1 (C/s•cm2 = A/cm2)

J = -nFD dcdx

kex 2c61

= -nF dcdx

x

c

Thinner

Larger c Larger k0

Larger kex

Proto-type Radical Battery:Radical Polymer Composite Cathode

WASEDA Univ.

Graphite Anode (10 m)

Separator + Electrolyte (20 m): (1.5 M LiPF6 EC/DEC)

Radical Polymer Composite Cathode (70 m): PTMA with Mol. Wt. 200K + 20% Graphite fiber 150 nm × 5 m)

+

-

NEDO Projects on “Radical Battery for Ubiquitous Power”

Energy Density: 120 Wh/L, Power Density: 11 kW/L, Cell Thick: 100 m

Screen Printing Process for Electrode Fabrication

WASEDA Univ.

Radical Polymer/C Composite Ink

Al Current Collector

MaskMesh

“Printable Power”

Ragone Plot

WASEDA Univ.

Q

VRadical Battery

Capacitor

Radical Batteryvs. Capacitor

・ Constant Output Voltage

・ Free from Self-discharge

Capacitor

Radical Battery

Li-ion

Ni-MHPow

er D

ensi

ty (k

W/k

g)

Energy Density (Wh/kg)1 10 100 10000.1

1

10

100

Ubiquitous Power

WASEDA Univ.27

Ultimately Enriched Unpaired Electrons Placed

on Non-Conjugated Polymer Scaffolds

Charge TransportCharge Separation Charge Storage

Hole-Transporting LayerPolymer Memory Photovoltaic Cell

Rechargeable Batteries

Electrochromic Display

OOOO

N NO O

n

O O

NO

n

O

O

NO

n

NO

O n

NNO O

n n

O O

Bias

Totally Organic-Based Dye-Sensitized Solar Cell

e- e- e-

e-

e-

色素

0 -4.5

1.0 -5.5

Eo (V vs NHE) E (eV) e- e- e-

OO

n

NO

O O

n

h

O O

NO

n

n

O O

Dye

WASEDA Univ.WASEDA Univ.

Radical Polymers as a New Class of Electroactive Materials: Their Electronic Functionalities Leading to Organic Devices

MemoryDiodeSwitch Solar Cell

BatteryCapacitor

Recharge-able Solar Cell

Trans-ducer

Charge Storage forWet-type Energy Storage Device

Charge Separation forEnergy Conversion Device

Charge Transport forElectrical Conductor

Electrochromic Cell

Adv. Mater., 21, 2339 (2009).