A team in Germany has now demonstrated a new lithium-metal battery with a density well beyond the significant 500-Wh/kg benchmark and an ability to retain its performance across hundreds of cycles.

Today's lithium-ion batteries do a wonderful job of keeping the modern world running, from electric vehicles to smartphones, to laptop computers, but scientists see a lot of potential that could be unlocked through tweaks to their architecture. One of the more promising possibilities is swapping out the graphite used in one of the battery's electrodes for pure lithium metal, a material that can hold as much as 10 times the energy.