LI-ION BATTERIES FOR NEXT GENERATION EV

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1 LI-ION BATTERIES FOR NEXT GENERATION EV

2 ecartec 2016 Li-ion batteries for next generation EV - Content Next Generation EV Vehicle segments Requirements Key Performance Indicators KPIs: Cost Energy Density Fast Charging Safety Lifetime Battery Management System BMS Summary and outlook 2

3 NEXT GENERATION EV VEHICLE SEGMENTS AND REQUIREMENTS

4 ecartec 2016 Next generation EV Vehicle segments City- EV Vehicle classes Mini Sub-compact Compact Compact class Vehicle classes Compact- and middle class Compact class SUVs Roadster Premium class Vehicle classes Upper- and higher middle Luxury Large-SUVs Sport EV-dedicated vehicle platforms drives differentiation of EV battery by: Cost, energy density, power and lifetime 4

5 ecartec 2016 Next generation EV Use cases, requirements City- EV Use cases Battery requirements 1 Cost Cycle Life Volumetric Energy Vehicle classes Mini Sub-compact Compact Urban use 2nd car Fleet cars Car sharing Robot taxis Charging C-rate Power Specific Energy 5

6 ecartec 2016 Next generation EV Use cases, requirements Compact class Use cases Battery requirements 2 Cost Cycle Life Volumetric Energy Vehicle classes Compact- and middle class Compact class SUVs Roadster City use Rural use Highway Charging C-rate Specific Energy Power 6

7 ecartec 2016 Next generation EV Use cases, requirements Premium class Use cases Battery requirements 3 Cost Cycle Life Volumetric Energy Vehicle classes Upper- and higher middle Luxury Large-SUVs Sport Long distance driving Business cars Charging C-rate Power Specific Energy 7

8 Driving Range [km] ecartec 2016 Driving range requirements Assuming pack cost 20% of vehicle sales price is economical limit: Small economical limit Small Small technical technical limit limit 2 Compact/Middle economical limit Compact/Middle economical limit Compact/Middle technical limit Premium economical limit 3 Premium economical limit Premium technical limit Premium technical limit Premises battery volume Small: 130 l Compact/Middle: 280 l Premium: 320 l Small and medium class vehicles limited mainly by battery cost Premium EV limited by volumetric energy density 8

9 ecartec 2016 Next Generation EV Requirements, overview Small Compact / Middle Premium Range (WLTC incl. acc.) km km km Battery energy kwh kwh kwh Continuous power mechanical kw kw kw Peak power mechanical kw kw kw DC charging power kw kw kw Battery Pack Wh/l Wh/l Wh/l High volumetric energy density required for driving range comparable to ICE 9

10 KEY PERFORMANCE INDICATORS (KPI)

11 Cost [EUR/kWh] ecartec 2016 Cost Cell Pack

12 Energy density [Wh/l] ecartec 2016 Energy density Cell Pack

13 80 % ecartec 2016 Fast Charging Market analysis Voice of user Voice of customer Requirement for Fast Charging time to 80% SOC Mainstream Premium cars 20 min 15 min 13

14 ecartec 2016 Fast Charging Expected infrastructure 2020 Europe Charging power 3 kw 50 kw 150 kw Premium services 22 kw 350 kw North America Charging power 3 kw 50 kw 150kW Premium services 350 kw Asia Charging power 3 kw 50 kw 100 kw Premium services Infrastructure will provide enough power for Fast Charging in the future 14

15 Current Voltage ecartec 2016 Fast Charging Charging sequence Today Charging sequence: CC CV CC CC AC CV CV Up to 30% Future New charging sequence: Challenge: No Lithium plating, no unreasonable aging due to fast charging sequence CC AC CV Time CC Constant Current CV Constant Voltage AC Anode Controlled New BMS algorithms for Fast Charging: Expected potential of new sequence compared to CC / CV: up to 30% time reduction 15

16 OCV ecartec 2016 Fast Charging Li-plating Simplified equivalent circuit Li-plating j Cathode_SF I cell + R diff_c R trans_c Real structure R trans U cell R diff1 R diff2 R diff1_a j Anode_SF j Li-plating R diff2_a R trans_a - Excessive Li-plating can be avoided in case j Anode is kept below j Li-plating Li-plating avoided by control of BMS Accurate cell models required! 16

17 ecartec 2016 Fast Charging Cell design, impact on other KPIs Sensitivity of KPIs on Fast Charging capability Fast Charging capability influenced by design parameters, e.g. electrode thickness, electrode porosity KPI 1C 2C 3C Gravimetric energy density 103% +3% 100% -3% 97% Volumetric energy density 105% +5% 100% -3% 97% Cost 95% -5% 100% +7% 107% Impact of fast charging (1C 3C) on affected KPI is limited No severe conflict with market requirements expected 17

18 ecartec 2016 Safety Today Different safety concepts available Small cells, safety measures on pack level High capacity cell with integrated safety devices Focus on abuse tests, e.g. nail penetration Future Safety concept has to ensure product safety during whole product life cycle (starting from cell manufacturing, ending with recycling) Best concept for large EV batteries? 18

19 ecartec 2016 Lifetime Lifetime is a combination of Calendar life Cycle life 12 years & Cycle life requirement: km Calendar life requirement will only change, in case of new business models Today (< 25 kwh): 2500 cycles for km Future (75 kwh): 700 cycles for km Less # of cycles is enabler for introduction of new technologies, e.g. Si-anode 19

20 BMS

21 SOC SOH ecartec 2016 Battery Management System BMS Calculation of SOC and SOH Failure 5 % Today Next Gen EV Electrical driving range 150 km km Inaccuracy BMS 5% 2% 5% Not used driving range 15 km km Significant benefit of high accuracy BMS regarding driving range in Next Generation EV 21

22 SUMMARY AND OUTLOOK

23 ecartec 2016 Summary and outlook Li-ion battery technology will make significant improvement until 2020 especially regarding energy density and cost Thank you! Li-ion batteries will fulfill requirements regarding volume, cost and fast charging of next generation EV Safety of high capacity batteries with high energy density is very challenging New safety concepts required 23