Even rechargeable batteries eventually die. Month after month of using a battery, topping it up and repeating the cycle gradually reduces its ability to hold a charge and the amount power it can supply. That’s why electric vehicle (EV) manufacturers suggest replacing the battery pack when its storage capacity drops below 80 per cent of maximum, and have 8 year warranties.

WISE researchers envisioned a different approach. A battery is only as strong as its weakest cells, propose researchers in…