A new battery idea could power electric cars for 1,200 miles, someday

A report says a new kind of battery, called lithium-air, could let an electric car travel 2,000 km, about 1,242 miles. Nobody has built such a car. The claim comes from a Chinese tech outlet, and the battery maker tied to the buzz has not given a launch date.

Where the claim came from

According to CarNewsChina, the figure traces back to IT Home, a Chinese tech outlet. IT Home says lithium-air batteries could pack up to five times more energy than solid-state ones. The buzz is linked to CATL, a battery maker. Its Chief Scientist, Wu Kai, called lithium-air a long-range research goal at this year's Equipment Powerhouse Forum. CATL has not promised any timeline.

How it works

In a regular lithium-ion battery, lithium lives inside both electrodes, the two sides where energy is stored and released. A lithium-air battery uses lithium metal on one side and pulls oxygen from the air on the other. That removes a heavy material the battery would otherwise carry, so it can store far more energy for its weight.

On paper, the chemistry can reach roughly 3,505 Wh/kg, a measure of energy stored per kilogram. But that number only describes the chemistry. A real battery needs extra parts, including air-handling hardware, and the figure drops a lot.

Why it is not close

• Air also carries water vapor and carbon dioxide, which can wreck the lithium and gunk up the battery.
• Filters and humidity control would add weight and eat into battery power.
• Recharging can produce harmful oxygen byproducts that slowly eat away at the battery and shorten its life.
• Storing lots of energy means little if the battery cannot deliver quick bursts of power for passing or fit inside a car.

What to do

Anyone shopping for an electric car should not wait for this battery. For now, CATL is focused on sodium-ion and all-solid-state batteries, which are much closer to hitting the market. Near-term range gains will come from other types. A 2,000 km electric car is still a theory rather than something you can buy.