As lithium batteries cycle, they accumulate little islands of inactive lithium that are cut off from the electrodes, decreasing the battery's capacity to store charge. But the research team discovered that they could make this "dead" lithium creep like a worm toward one of the electrodes until it reconnects, partially reversing the unwanted process.

Adding this extra step slowed the degradation of their test battery and increased its lifetime by nearly 30%.

"We are now exploring the potential recovery of lost capacity in lithium-ion batteries using an extremely fast discharging step," said Stanford postdoctoral fellow Fang Liu, the lead author of a study published Dec. 22 in Nature.