PROGRESS OF BATTERY SYSTEMS AT GENERAL MOTORS

Manfred Herrmann

Roland Matthé

World Mobility Summit Munich

October 2016

AG

EN

DA

DEVELOPMENT OF ELECTRIFICATION

ELECTRIFICATION

BATTERY SYSTEMS

PROGRESS OF BATTERY SYSTEMS

EREV BATTERIES

BEV BATTERIES

GM Milestones in Electric PropulsionFrom the first fuel cell vehicle to EREV and BEV

1966

1968 1972 1987 1991 1996

2000 2007

2010/11

1972 Lunar RoverAG-Zn primary battery

1990 ImpactElectric vehicle concept car

1997 S10 Electric

1968 Electrovair 1972 Electro-Vette 1987 Sunraycer 1991 Impuls 1996 EV1 2010 Volt 2011 Ampera

1966 Electrovan with fuel cell 2000 HydroGen1 2007 HydroGen4

Space technology

New materials for FC membranes

Li-ion batteries Longer life Reduced cost Shorter charge time No range issues

ZEV mandate Limited range Long charge time Range anxiety Lead acid & NiMh

2017 Ampera-e

GM Electrically Driven Vehicles1987 – 2012 from Lead acid to Lithium Ion batteries

1987 1990 1991 - 1993 1996 - 1999 2007 2010 - 2012

GM Sunraycer GM Impact Opel Astra Impuls GM EV1Chevrolet S10 EV

Opel HydroGen4Chevrolet Equinox Fuel CellChevrolet Tahoe2-Mode Hybrid

Opel AmperaChevrolet VoltBuick LaCrosseeAssist

AGgZnbatteries

Lead-Acidbatteries

NiCd, NaNiCI2NiMH batteries

PbPbO2NiMH batteries

Fuel CellNiMH batteries

Lithium-Ionbatteries

PM synchronousmotorMosFET

AC inductionmotorMosFET

AC inductionIGBT

AC induction motorIGBT

PM synchronousmotorIGBT

PM synchronousmotorIGBT

5

CONSERVATION DISPLACEMENT

Petroleum and Biofuels(Conventional and Alternative Sources)

Increasing Electrification

Electricity (Zero Emissions Energy Sources)

Light

Electrification

ExtendedRange Electric

Pure

ElectricHEV PHEV

MILD HYBRID TO PURE ELECTRIC TO DISPLACE PETROLEUM

6

ELECTRIFICATION AT GENERAL MOTORS

HEV PHEV EREV BEV

Gen 1

Gen 2

Gen 2

Battery

2016 CHEVROLET MALIBU HYBRID -- HEVSTYLE

Mid-size 4-door SedanSeats 5

RANGE & FUEL ECONOMY47 MPG combined (GM est.EPA)Estimated 5.0 L/100km in WLTP540 Miles total range (GM est)Estimated total range 870 km

PERFORMANCE0-60 mph in 7.8s0-30 mph in 2.9s

2016 CHEVROLET VOLT – EREV

STYLESmall 5-door hatchback

Seats 4+1

RANGE & FUEL ECONOMY53 miles EV (EPA City &HWY mix)

85 km (WLTP estimated)

420 miles total range

676 km

42 MPG combined

5.6 l/100km

PERFORMANCE0-60 mph in 8.4s

0-30 mph in 2.6s

STYLE

Small 5-door CUV

Seats 5

RANGE & FUEL ECONOMY

238 miles EV total range (EPA)

> 500 km (NEDC)

PERFORMANCE

0-60 mph in < 7s

2017 CHEVROLET BOLT EV – BEV2017 OPEL AMPERA-E BEV

KEY METRICS FOR BATTERIES: HEV – EREV(PHEV) - BEV

1 0

HEV EREV (PHEV) BEV

Energy 1.5 kWh 18.4 kWh 60 kWh

Discharge Power 52 kW 120 kW 160 kW

Mass 43 kg 183 kg 429 kg

Power to Energy

Ratio kW per kWh

35 6.5 2.7

*) ilustration, not to scale

** *

MODULARITY ENABLES EREV AND PHEV BATTERY

Pouch cells integrated in modules.

Design enables parallel connections.

Common Modules used in different

arrangement.

EXTENDED RANGE ELECTRIC VEHICLES

1 2

Gen 1:

Opel Ampera MY 2012

Chevy Volt (not shown)

Gen 2:

Chevy Volt MY 2016Gen

No. of cells: 288

Liquid thermal system (Cooling & Heating)

Energy content: 16 kWh (> 10 kWh useable)

Power discharge: > 115 kW

Nominal voltage: 360 V

Charging time: 4 h @ 230 V & 16 A

Warranty: 8 years / 160,000 km

System weight: 193 kg

EREV Battery System Gen 1 Opel Ampera MY 2012GEN 1 BATTERY SYSTEM EREV

GEN 2 BATTERY SYSTEM EREV)

OPTIMIZED CHEMISTRY AND NEW CELL DESIGN

Energy density increased by 20 percent (pack Wh/l)

Total capacity increased:

Fewer – 192 cells /larger cells (~50% thicker)

Simplified controls architecture

Total mass reduced by 10 kg

Active thermal system (Cooling, heating)

-> More energy at reduced cost

BATTERY DETAILS

Gen 1 (2010) Gen 2 (2016) Difference

Mass 193 kg. 183 kg - 10 kg

Energy 16 kWh 18.4 kWh +15 %

Cells 288 192 -96 cells

EREV GEN 2 CELL CAPACITYRatio of NMC-LMO optimized for desired power to energy ratio

Single layer “G4” separator for 9% increase in power

6% increase in active material area

Cell height increased by increasing available module height

Cell width increased by “wing folding” of the pouch

Results (Comparing the latest Gen 1 cell to the Gen 2 cell)

12.3% improvement in energy density (Wh/l)

10% improvement in specific energy (Wh/kg)

Cells by

BATTERY ELECTRIC VEHICLES (BEV)

Chevy Spark Opel Ampera-e

Chevy Bolt

Gen 1: Gen 2:

BEV BATTERY SYSTEMS GEN 1 & 2

1 7

Vehicle Name Gen 1 Gen 2

Range (EPA) 82 Miles 238 Miles (EPA)

Battery Chemistry Lithium Ion Lithium Ion (Nickel – rich)

Battery Nominal Energy 18.4 kWh 60 kWh

Battery Mass 215 kg 430 kg

Max Battery Power 120 kW 160 kW

Battery Nominal Voltage 360V 350V

Battery Position Underfloor Underfloor

Battery Thermal SystemLiquid active thermal

control

Liquid active thermal

control

Energy Density Pack 86 Wh/kg 140 Wh/kg

Gen 1

Gen 2

PROGRESS OF BEV BATTERY – GEN 1 TO GEN 2

• Triple the energy to 60 kWh • +50% energy density in Wh/kg

• Power increase by 33% to 160 kW• Effective vehicle integration – ease of passenger egress/ingress

• High volumetric density -> +150 % volumetric energy density Wh/l• More than double the cell capacity in Ah

• Large format pouch cells, footprint to enable „flat pack“

• lower P/E ratio, while meeting power requirements

• Designed for long-life with advanced thermal system and controls

1 8

BEV Gen 2 cell

GEN 2 BEV BATTERY

1 9

Technology Enablers for 60 kWh

• Improved integration into vehicle structure

• Cell sizing to module format optimization

• Cell and bi-cell optimization for power and energy

• Advanced cell chemistry – Nickel-rich NMC

• Active cooling / heating packaging optimization

• Topology optimization to meet all internal and external safety and crashworthiness requirements

TARGETS FOR BATTERY DEVELOPMENT

Reduce:

Cost [$]

Weight [kg]

Volume [dm³]

Increase:

Energy [kWh]

Power [kW]

Energy throughput or cycle life [kWh]

Range of temperature [°C]

2 0

Introduction [calendar years]

En

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[kW

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Tro

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hpu

t[k

Wh

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em

pe

ratu

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Co

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ass

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Siz

e [

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Progress of batterie packs is „evolution“ and „optimzation“

Introduction [calendar years]

BATTERY TECHNOLOGY ROAD MAP REALITY

2 1

Graphite/Layered,

Spinel, or Olivine

Cathode

Silicon or Metal Alloy

High-V Cathode

Li-Sulfur or Li-Air or

beyond lithium...

Today 2020 202x

Challenges

Cell Expansion

Cycle Life

Electrolyte Stability

Manufacturing

Cost

Brownstown Battery Assembly Plant opened in summer 2009

Assembles lithium-ion batteries for:

Chevrolet Volt

Chevrolet Malibu Hybrid

Chevrolet Silverado eAssist

GMC Sierra eAssist

Buick LaCrosse Hybrid

Cadillac CT6 Plug-In Hybrid

GM BROWNSTOWN BATTERY ASSEMBLY PLANT

2 2

CONCLUSION

• EREV batteries improved significantly

• Increased energy

• Reduced Cost

• GEN 2 BEV battery system delivers energy of 60 kWh and power of 160 kW

• Energy density (mass) Wh/kg plus 50% (system level)

• Energy density (volume) Wh/L plus 150%

• Reduction of specific ($/kWh) system cost

• Progress in the future will require Lithium Ion cell material innovation, Lithium Ion cells and further improved battery pack design.

• Executing the battery roadmap requires resources in research and engineering

2 3

Thanks to all involved engineers at General Motors

and our suppliers!

Thank you for your attention!