Bosch future trends of batteries

CR/RTC-NA | 10/1/2011 | © 2011 Robert Bosch LLC and affiliates. All rights reserved.

Future Trends of Batteries for E-Mobility

Research and Technology Center North America


Dr.-Ing. Horst Muenzel Bosch Research and Technology Center, Palo Alto

Baden-Wuerttemberg Forum “E-Mobility”

Stanford University October 24, 2011

1




Market Trend and Portfolio for e-mobility

The Battery System is a Key Component

Battery Technology Challenges and Trends

Conclusions

Outline

2




Market for electric-powered vehicles will grow long-term Total market:

Uni

ts [M

illio

n ve

hicl

es]

and

0

5

10

15

20

2008 2012 2020

EV and PHEV

Hybrid vehicles (HEV)

Other (FlexFuel, CNG, LPG)

Uni

ts [m

illio

n ve

hicl

es]

4.8

19.2

7.2 10.2

6.0

3.0

0.002

4.2

1,9

*) Estimated total production

*)

0.6

0.3 1.9

9.4

Total market: 70 M 82 M 103 M

3 -10 units

3




“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

Our view for 2050

4




Bosch is involved in many areas of e-Mobility

Charging Stations for Electric Vehicles

Power Train for E-Bikes

FUTU

RE

Research and Advanced Engineering for futureElectric Vehicle Concepts

Battery of SBLimotive A Joint Company ofSamsung and Bosch

E-Machines andPower Electronics forHybrids and EV

ABS, ESP, Break-Booster

Starter and Generatorsfor Start/Stop Systems

Software for Infra-structure Integration

Charger EV and PHEV

Hydraulic Hybrid Systems & Industrial Drives

Navigation Systems

5




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

Dedicated battery cells and systems for each vehicle segment required

6

Typical car segments:




Battery System Design: Scalable, flexible, modular

Cell

Module

Battery System

Subunit

7




Integrated Engineering along the Value Stream

Chemistry Cell Battery System Automotive Integration Aftermarket

• Materials for AnodeSeparator, Electrolyte, Cathode

• Electrode- & cell manufacturing

• Prismatic cell design

Pack manufacturing:• Thermal Management• Electrical components• Housing• Battery assembly

• Layout of electrical system• Expertise in system tailoring • Strong validation• Vehicle integration

• Spare part supply/logistics• Diagnostics (software/test

equipment)• Repair & maintenance• Training for automotive

workshops

Features Safe materials Ceramic layer to prevent

inner short circuits Shut down function

of separator Flame retardant additives Active materials with

improved inherent stability

High quality manufacturing Safety proved cell-design Balancing of electrodes Clean room conditions

Flexible construction kitbased on modular concept for different customers & applications

Packaging optimized w/ reduced weight & size

Lifetime optimized cell bracing, integration of automotive qualified materials & parts

Serviceability

Common specification Aligned system quotations

• Electrical machine • Power electronics • Battery

Common customer approach

Worldwide network High quality spare parts

and diagnostics Original equipment

know-how in all automotive technologies

8




Hardware and Software Integration is important

BMS HardwareCooling System BMS Software PackCells & Modules

Products & Engineering Services Engineering Services

High Power

High Energy

Internal liquid cooling system

Valve, Pump & Chiller, Heater

Interface to vehicle refrigerant circuit, or environment

Battery Management ECU

SCS Units,Safety & Fuse Box

Relays, Fuses, Safety plug,

Sensors, Cell monitoring& Balancing

State of Charge and Health Monitor

Safety Functions

Thermo-management

Communication & OBD System

Cells/Modules

Cooling System

BMS HW&SW

Wiring harness

Degassing structure-plugs

Housing and external interfaces

9




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.

Battery Research and Development Challenges

10




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

11




Challenge: Specific energy needs to be increased

12

0

50

100

150

200

250

300

350

0 100 200 300 400

Veh

icle

rang

e (k

m)

Battery system weight (kg)

Target window for full range EV

GM Volt (electric range only)

BMW Mini E

Tesla Roadster




New Battery Cell Designs: Research ongoing

Lead Acid

NiMH Li-Ion Li/Sulfur Li/Air

Specific energy (Wh/kg)

800

700

600

500

400

300

200

100

0

800

700

600

500

400

300

200

100

0

Shift to advanced Li-ion anodes and cathodes

Achieved

Future Potential

Technology change; need to overcome fundamental barriers

13




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.

…

14




Challenge: Lifetime needs to be verified

Complex aging mechanisms Carefully designed experiments and modeling required for lifetime predictions

Some examples:

Li+

Particles can lead to fracture and subsequent battery cell capacity loss

Aging of standard CE battery cells at different temperatures

15




Example: Advanced simulations to predict cell behaviour

Goal: Prediction of critical thermal reactions

SIMULATED CELL CAN T

SIMULATED JELLYROLL T

EXPERIMENTAL INFRARED CAN T

Goal: Battery performance simulation to determine temperature distributions within cells

Model can be used to improve cooling strategy and to improve cell design for longer lifetime

16




Challenge: Cost of Li-ion batteries needs to be reduced

Energy per mass (Wh/kg)

Cost per energy ($/kWh)

Today’s values:

Nissan Leaf (small passenger car)

Tesla Roadster (performance car)

24 kWh, 150 km range

53 kWh, 400 km range

$18k pack

$35k pack

75 to 130 (battery system)

750 (battery system)

17




Cost Trend

Sources: Tiax, Institute of Information Technology, SB Limotive

Battery system cost ($/kWh)

2011 2015 2020 0

250

500

750

0

250

500

750 At this price a 25 kWh pack (150 km range) would cost about $7500

Increasing production, increasing energy per mass / volume

18




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.

Conclusions

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