Quantifying the Cold-Weather State-of-Power Benefits Enabled By Multi-Chemistry EV Battery Pack

The degradation of electric vehicle (EV) range in winter is widely acknowledged, while the degradation of state-of-power (SOP) is more subtle and less recognized. This work analyzes a multi-chemistry battery (MCB) pack, composed of lithium-iron-phosphate (LFP) and lithium-titanium-oxide (LTO) cells, to quantify its improved cold-weather SOP performance compared to a conventional single-chemistry battery SCB) pack in winter commute scenarios. Simulation results, utilizing a measured drive-cycle on a Tesla Model 3 EV, showed that the cumulative time where maximum propulsion and regenerative braking are available increased from 109 hours with the SCB pack to 142 hours with the MCB pack, over the total of 144 hours of driving during the winter. The analysis was repeated for batteries near end-of-life, demonstrating that the MCB delivers more benefits as the batteries age.