Li-Ion Batteries for Low Voltage Applications Christoph Fehrenbacher 19 October 2016
OEM Portfolio Planning; A Balanced Strategy for Fuel Economy Low voltage hybrids are a cost effective solution for higher volume impact on fuel economy requirements Fuel Economy / Emsission Requirements EV HEV Mild hybrid Low voltage 48V & 12V Micro-hybrid sales volume
Comparison of Lithium-Ion Chemistry Fit Considerations for 48V mild HEV battery solutions High Energy EV EV EV EV w/ w/ fast fast charge charge PHEV Transportation Battery Solutions Single Battery Micro-Hybrid 12V Single Battery (Europe/VDA) HEV HEV 48V Hybrid Dual Battery/ Aux 12V Micro-hybrid High Power NMC (13s) (20s) LTO Considerations of market solutions LFP (14s) + Cost will limit favorability of LTO in this application due to inherent series cell counts + NMC and LFP have most potential for mainstream success based on cost A123 concluded that LFP could be optimized to further reduce impedance and thus be the best fit chemistry high P/E ratio 48V applications NMC based solutions may be required for 48V applications with high E/P ratio 3
Segmenting OEM Requirements 48V battery systems Luxury features & further fuel efficiency Fuel efficiency focus One battery solution can address the requirements of this segment
Sizing a 48V Battery Market segment: Fuel efficiency focus Lithium-ion cells used for HEV applications have power/energy ratios that work well in 48V applications, but most are not sized properly to balance energy, thermal requirements, and cost Energy throughput requirements for 48V battery systems range from 100-200Wh + Sizing toward the maximum of 180-200Wh yields approximately 4Ah capacity at EOL Assuming 50% capacity needed for usable energy window and capacity fade over life, approximately 8Ah BOL capacity is required 5
Introducing UltraPhosphate 8Ah prismatic cell Impedance Change by Attribute 100% 80% HEV Electrode High P/E Ultra Electrode Extreme P/E 60% 40% 20% 0% Cathode Anode Electrolyte Loading 14Ah Nanophosphate [HEV] 8Ah UltraPhosphate [48V] Nanophosphate UltraPhosphate UltraPhosphate improvements total 65% additional power over previous HEV design 6
A123 48V UltraPhosphate Battery Launching in Q4 2016 Specification Unit Performance Pack Configuration - 14s1p Chemistry - UltraPhosphate Capacity Ah 8 Minimum Voltage* V 24 Nominal Voltage V 46 Maximum Voltage* V 54 SOC Range % 30-80 10s Discharge @25 C, 50% SOC kw 15 60s Discharge @25 C, 50% SOC kw 7.5 10s Charge @ 25 C, 50% SOC kw 16 60s Charge @ 25 C, 50% SOC kw 9 Usable Energy @ 25 C Wh >180 Mass kg 8 Communication Protocol CAN Length x width x height mm 304 x 180 x 96 Design goals + Compact with optimized height profile + Thermal efficiency to avoid need for active cooling in many applications + Crush resistant for applications packaged within crash zones 7
Comparison of Lithium-Ion Chemistry Fit Considerations for 12V battery solutions High Energy EV EV Transportation Battery Solutions EV EV w/ w/ fast fast charge charge 12V Single Single Battery Battery Micro-Hybrid PHEV (Europe/VDA) HEV HEV 48V Hybrid Dual Battery/ Aux 12V Micro-hybrid High Power NMC Not matched for voltage Nanophosphate /Ultraphosphate (LFP) Lithium Titanate (LTO) Key requirements + Meet todays power net operation voltage requirements + Balance of power (CCA) and energy (ignition-off draw) + Minimize cost Key applications + Light-weighting and micro-hybridization + Prepare for expiration of EU s lead ban exemption
Standard Construction Leads to Economies of Scale Led by the five German automakers Capacity Size Package 20Ah LN0 40Ah LN1 60Ah LN2 80Ah LN4 Lead ban preparation in Europe is another driver to economies of scale, although legislation timing is unknown Common specification for Li-ion Starter Batteries (LiSB) was initially released in December 2013 + Form factor, capacity & cold crank performance Some OEM programs still deviate from this template spec
UltraPhosphate also supports 12V Starter Battery Cold crank gap with lead-acid addressed Ultra Electrode Extreme P/E 8Ah UltraPhosphate HE Electrode High E/P 20Ah UltraPhosphate A123 has achieved parity with lead-acid cold crank performance at -30 o C, erasing the performance barriers to mass market 1000 900 800 700 600 500 400 300 200 100 0 * Tested to BS EN 50342-1 lead-acid AGM 12V 60Ah Cold Cranking Amps (7.5V minimum for 10 seconds*) A123 Gen2 12V 60Ah A123 Gen3 12V 60Ah -18degC -30degC 10
Li-Ion Batteries for Low Voltage Applications UltraPhosphate Lithium-Ion Technology + Outstanding cold cranking power + Outperforms lead-acid technologies + Exceptional cycle-life + High charge acceptance 12V Starter Battery + 60% weight reduction over lead-acid + Solution for start-stop and recuperation demands + Compact solution 48V Battery + Supports fuel savings initiatives + Powerful charge acceptance + Potential to eliminate battery cooling system + Supports engine downsizing and electric supercharging