Researchers at the US Department of Energy’s SLAC National Accelerator Laboratory and Stanford University may have found a way to increase battery life in next-generation electronic devices.

As lithium batteries cycle through their life, they accumulate small islands of inactive lithium that are cut off from the electrodes, reducing the battery’s ability to store a charge. But the research team found that they could make this “dead” lithium crawl like a worm towards one of the electrodes until it reconnected, partially reversing the unwanted process.

Adding this extra step slowed down the degradation of their test battery and increased its lifespan by almost 30%.

“We are now exploring the potential of restoring the lost capacity of lithium-ion batteries with an extremely fast discharge stage,” said Fang Liu, a Stanford postdoc researcher and lead author of the study.

A large amount of research is focused on finding ways to make rechargeable batteries with lighter weight, longer life, improved safety and faster charging speeds than the lithium-ion technology currently used in mobile phones, laptops and electric vehicles. Particular attention is being paid to the development of lithium metal batteries that can store more energy per unit volume or weight. For example, in electric vehicles, these next-generation batteries could increase mileage per charge and possibly take up less trunk space.

Both types of batteries use positively charged lithium ions that move between the electrodes. Over time, some of the lithium metal becomes electrochemically inactive, forming isolated islands of lithium that no longer connect to the electrodes. This results in loss of capacity and is a problem for lithium metal technology and for fast charging lithium ion batteries.

However, in a new study, researchers have demonstrated that they can mobilize and recover isolated lithium to extend battery life.