Researchers used nanoscale manufacturing techniques from the semiconductor industry to design a copper current collector that helps lithium build up evenly during battery charging.

Electric vehicles could travel farther on a single charge if their batteries could store more energy without getting bigger or heavier. A promising alternative, known as an anode-free battery, eliminates materials such as graphite that normally store lithium during charging, saving weight and space.

Lithium instead deposits directly onto thin copper foil, where repeated charging and discharging can cause it to build up unevenly into sharp, branching spikes called dendrites. The protective layer over the lithium also becomes unstable, reducing battery performance and shortening its lifespan.