There is a darker side to the battery market. When batteries reach their true end-of-life, they become , often containing lead, mercury, and cadmium.

While a new EV battery might cost $150–$250/kWh, a repurposed "second-life" battery can drop to $44–$180/kWh.

From a purely financial standpoint, the decision to buy used is driven by a stark price difference. Pre-owned batteries typically cost than new ones. However, this "discount" comes with an invisible tax: uncertainty .