Capacity Measurements for Second Life EV Batteries

After they reached the end of their useful EV life, lithium-ion batteries are still satisfactory for second life (SL) energy storage applications. However, spread in SL cell capacities may be much wider than EV, and this raises a question as to what type voltage equalizer (EQU) should used. Most users plan retain same passive EQU (PEQ) from but means battery capacity will worst battery, just it was EV. Unfortunately, if so, most cells under-utilized. This can corrected by using an active (AEQ) or hybrid, such bilevel (BEQ), provide close average; first, measured data is needed on actual size spread. To simplify reduce cost these measurements, new method proposed that provides average.