1. Future Trends of Batteries for E-Mobility
Future Trends of Batteries for E-Mobility
Dr.-Ing. Horst Muenzel
Bosch Research and Technology Center, Palo Alto
Baden-Wuerttemberg Forum “E-Mobility”
Stanford University
October 24, 2011
Research and Technology Center North America
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2. Future Trends of Batteries for E-Mobility
Outline
 Market Trend and Portfolio for e-mobility
 The Battery System is a Key Component
 Battery Technology Challenges and Trends
 Conclusions
Research and Technology Center North America
2 CR/RTC-NA | 10/1/2011 | © 2011 Robert Bosch LLC and affiliates. All rights reserved.

3. Future Trends of Batteries for E-Mobility
Market for electric-powered vehicles will grow long-term
Total market:
Total market: 70 M 82 M 103 M
20 19.2
3 -10 units
3.0
15
Units [Million vehicles]
and
Units [million vehicles]
6.0 EV and PHEV
10 9.4
0.3 Hybrid vehicles (HEV)
1.9
1,9
4.8 Other (FlexFuel, CNG, LPG)
5 0.6 0.002
4.2 7.2 10.2
0
2008 2012 2020*)
*) Estimated total production
Research and Technology Center North America
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4. Future Trends of Batteries for E-Mobility
Our view for 2050
 “The future belongs to e-mobility.
By 2050 2% or less of power trains will be internal combustion engines”
Dr. Bernd Bohr, Robert Bosch
Chairman of the Automotive Technology Business Sector
2011
Research and Technology Center North America
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5. Future Trends of Batteries for E-Mobility
Bosch is involved in many areas of e-Mobility
E-Machines and Battery of SBLimotive Navigation Systems Charger EV and PHEV
Power Electronics for A Joint Company of
Hybrids and EV Samsung and Bosch
Power Train for
E-Bikes
ABS, ESP, Break-Booster
Software for Infra-
structure Integration
Charging Stations for
Electric Vehicles
FUTURE
Hydraulic Hybrid Systems Starter and Generators Research and Advanced
& Industrial Drives for Start/Stop Systems Engineering for future
Electric Vehicle Concepts
Research and Technology Center North America
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6. Future Trends of Batteries for E-Mobility
Battery tailoring for electrified vehicle segments
Mild Hybrid Strong Hybrid Plug-In Hybrid Electric Vehicle
Battery type Medium Power High Power High Energy
Power 5 kW – 15 kW 20 kW – 60 kW 40 kW – 80 kW 15 kW – 150 kW
Energy 0.6 kWh – 1.8 kWh 5 kWh – 15 kWh > 15 kWh
Cell size 5 Ah 20 Ah – 40 Ah 40 Ah – 66 Ah
Power Energy
Typical car segments:
Dedicated battery cells and systems for each vehicle segment required
Research and Technology Center North America
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7. Future Trends of Batteries for E-Mobility
Battery System Design: Scalable, flexible, modular
Cell Subunit
Battery
System
Module
Research and Technology Center North America
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8. Future Trends of Batteries for E-Mobility
Integrated Engineering along the Value Stream
Chemistry Cell Battery System Automotive Integration Aftermarket
• Materials for Anode • Electrode- & cell Pack manufacturing: • Layout of electrical system • Spare part supply/logistics
Separator, Electrolyte, manufacturing • Thermal Management • Expertise in system tailoring • Diagnostics (software/test
Cathode • Prismatic cell design • Electrical components • Strong validation equipment)
• Housing • Vehicle integration • Repair & maintenance
• Battery assembly • Training for automotive
workshops
Features
 Safe materials  High quality manufacturing  Flexible construction kit  Common specification  Worldwide network
 Ceramic layer to prevent  Safety proved cell-design based on modular concept  Aligned system quotations  High quality spare parts
inner short circuits  Balancing of electrodes for different customers & • Electrical machine and diagnostics
 Shut down function  Clean room conditions applications • Power electronics  Original equipment
of separator  Packaging optimized w/ • Battery know-how in all
 Flame retardant additives reduced weight & size  Common customer automotive technologies
 Active materials with  Lifetime optimized cell approach
improved inherent stability bracing, integration of
automotive qualified
materials & parts
 Serviceability
Research and Technology Center North America
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9. Future Trends of Batteries for E-Mobility
Hardware and Software Integration is important
Cells & Modules Cooling System BMS Hardware BMS Software Pack
High Power Internal liquid Battery State of Charge Cells/Modules
cooling system Management ECU and Health Monitor
Cooling System
High Energy SCS Units,
Safety & Fuse Box Safety Functions
Valve, Pump & BMS HW&SW
Chiller, Heater
Thermo- Wiring harness
Relays, Fuses,
management
Safety plug,
Interface to vehicle Degassing
Sensors, Cell
refrigerant circuit, structure-plugs
monitoring
or environment Communication
& Balancing
& OBD System Housing and
external interfaces
Products & Engineering Services Engineering Services
Research and Technology Center North America
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10. Future Trends of Batteries for E-Mobility
Battery Research and Development Challenges
 A Li-ion battery is a complex chemical and physical system.
Optimization takes long and is difficult.
 The specific energy needs to be increased to improve the range of
the vehicle.
 The lifetime of automotive batteries needs to be verified.
 The cost needs to be reduced to increase market penetration and
customer acceptance.
Research and Technology Center North America
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11. Future Trends of Batteries for E-Mobility
Example: Li-ion battery cell cross section
Cathode materials
Li(Ni,Co,Mn)O2, LiFePO4, HV-NCM
Anode materials
Graphite, soft carbon, hard carbon, Si and Sn alloys
Binder & Solvents
PVDF variants, NMP, acetone, MEK, DMSO
Electrolytes
EC, PC, DMC, DEC, EMC, DME, THF, mixtures
Conducting salt
LiPF6, new salts e.g. LiBOB, LiBF4
Additives
SEI improver e.g. VC, overcharge protection, Al-
corrosion inhibitor, wetting agents
Separator
PE, PP, PET, inorganic composite, other
Packaging
Coating, drying, sealing, process control
Cell formation
Sources: Tiax, Exponent
Research and Technology Center North America
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12. Future Trends of Batteries for E-Mobility
Challenge: Specific energy needs to be increased
Target window
350 for full range EV
Tesla Roadster
300
250
Vehicle range (km)
200
150
BMW Mini E
100
50
GM Volt
(electric range only)
0
0 100 200 300 400
Battery system weight (kg)
Research and Technology Center North America
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13. Future Trends of Batteries for E-Mobility
New Battery Cell Designs: Research ongoing
Specific energy (Wh/kg) Achieved
Technology change; need to
overcome fundamental barriers Future
800 800
Potential
700 700
600 600
500 Shift to advanced Li-ion 500
anodes and cathodes
400 400
300 300
200 200
100 100
0 0
Lead NiMH Li-Ion Li/Sulfur Li/Air
Acid
Research and Technology Center North America
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14. Future Trends of Batteries for E-Mobility
Li/air research in early stages, but rapid progress
Top research challenges
 Demonstrate excellent chemical
reversibility.
 Achieve a high practical capacity.
 Determine if it’s necessary to
separate oxygen from air; if so, find
a way to do so.
 Achieve a high energy efficiency.
 Accommodate volume changes.
 …
Research and Technology Center North America
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15. Future Trends of Batteries for E-Mobility
Challenge: Lifetime needs to be verified
 Complex aging mechanisms
 Carefully designed experiments and modeling required for lifetime predictions
 Some examples:
Aging of standard CE battery cells at Particles can lead to fracture and
different temperatures subsequent battery cell capacity loss
Li+
Research and Technology Center North America
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16. Future Trends of Batteries for E-Mobility
Example: Advanced simulations to predict cell behaviour
Goal:
Battery performance simulation to determine Goal:
temperature distributions within cells Prediction of critical thermal reactions
SIMULATED CELL CAN T
SIMULATED JELLYROLL T
EXPERIMENTAL
INFRARED CAN T
Model can be used to improve cooling strategy and to improve cell design for longer lifetime
Research and Technology Center North America
16 CR/RTC-NA | 10/1/2011 | © 2011 Robert Bosch LLC and affiliates. All rights reserved.

17. Future Trends of Batteries for E-Mobility
Challenge: Cost of Li-ion batteries needs to be reduced
Energy per mass Cost per energy
(Wh/kg) ($/kWh)
Today’s values: 75 to 130 750
(battery system) (battery system)
Nissan Leaf 24 kWh, 150 km range $18k pack
(small passenger car)
Tesla Roadster 53 kWh, 400 km range $35k pack
(performance car)
Research and Technology Center North America
17 CR/RTC-NA | 10/1/2011 | © 2011 Robert Bosch LLC and affiliates. All rights reserved.

18. Future Trends of Batteries for E-Mobility
Cost Trend
Battery system
cost ($/kWh)
750 750
At this price a 25 kWh
pack (150 km range)
would cost about $7500
500 500
250 250
Increasing production, increasing energy per mass / volume
0 0
2011 2015 2020
Sources: Tiax, Institute of Information Technology, SB Limotive
Research and Technology Center North America
18 CR/RTC-NA | 10/1/2011 | © 2011 Robert Bosch LLC and affiliates. All rights reserved.

19. Future Trends of Batteries for E-Mobility
Conclusions
 The market for electric powered vehicles grows significantly. However
internal combustion engines will still dominate the market for many years.
 The battery is the key component in electrical vehicles and is a complex
system with many subcomponents.
 Batteries for HEV and PHEV have reached series production status. First
EV-solutions with limited driving range are enabled by batteries.
 Among the top R+D Challenges of batteries are the increase in specific
energy, cost reduction, safety aspects and lifetime verification
 Li/S and Li/air battery systems are in research focus. They may offer a
longer range and lower cost in future.
Research and Technology Center North America
19 CR/RTC-NA | 10/1/2011 | © 2011 Robert Bosch LLC and affiliates. All rights reserved.