Bilevel vs. Passive Equalizers for Second Life EV Batteries

Once lithium-ion batteries degrade to below about 80% of their original capacity, they are no longer considered satisfactory for electric vehicles (EVs), but still adequate second-life energy storage applications. However, once this level is reached, capacity fade increases at a much faster rate, and the spread between cell capacities becomes wider. If passive equalizer (PEQ) from EV used, battery remains equal that worst in stack, just like it was EV. Unfortunately, eventually weaker than average, other cells not fully utilized. operated while use, an active (AEQ) can increase higher value close AEQs more expensive cost effective. be shown bilevel (BEQ), PEQ/AEQ hybrid, also provide very average lower AEQ.