Fighting Has Broken Out Over How Long Lithium Metal Can Sit on the Shelf

A new paper has claimed up to a 25% capacity loss

Lithium in its pure extracted state in evaporation ponds at Uyuni Salt Flat, Bolivia. Photo: Pablo Cozzaglio/AFP/Getty

For years, they were the Don Quixotes of the battery world — tinkerers in pure lithium metal romantically seeking to install them in batteries, only to find them catching fire and the answers they thought would fix them a mirage. Then, over the last six months, these People of La Mancha became the toast of Silicon Valley and Wall Street, winning high-dollar valuations in SPAC deals and courted by virtually every major automaker in the world.

Now, a new paper published Monday at Nature Energy has triggered a heated debate in the battery community, asserting that in certain cases, lithium-metal batteries suffer a catastrophic loss of lifetime capacity. The issue is calendar life — how many years a battery can be useful, regardless of whether the vehicle in which it’s installed is driven or not. The paper, written by nine authors at Stanford University led by Yi Cui, a materials scientist, found that in extreme testing, lithium-metal batteries lose up to 25% of their lifetime capacity just sitting around.

Major automakers including General Motors and Volkswagen are relying on pure lithium-metal batteries to make next-generation electric vehicles ultra-affordable and allow them to crack the…