World’s first 18650-sized potassium-ion battery aims to fill lithium gap

The vast majority of our portable electronic gadgets, and the new wave of electric transportation, are powered by lithium batteries. Texas-based startup Group1 has developed a more sustainable alternative, and has now launched the world’s first 18650 potassium-ion battery.

Group1 was co-founded in 2021 by battery tech veterans, including Leigang Xue who currently serves as Chief Product Officer but previously worked in the lab of 2019 Nobel Laureate and battery pioneer Dr. John Goodenough at University of Texas at Austin – who co-invented the Li-ion battery.

It was in this lab that Dr. Xue invented the company’s Potassium Prussian White (KBW) cathode material – which is reported to be the key development that enables production of the “safer, quickly charging, more efficient and sustainable” potassium-ion battery (KIB).

To make a KIB cell, KBW is paired with a commercial-grade graphite anode, along with readily available electrolyte formulations and separators – with the company also highlighting the distinct lack of critical minerals like lithium, cobalt, nickel and copper in the new batteries.

“As our transition away from fossil fuels accelerates, the demand for lithium-ion batteries is spiking quickly, and our lithium supplies will soon be incapable of meeting that demand,” said CEO Alexander Gira as the company came out of stealth in 2022. “Group1 and potassium-ion batteries can provide a viable alternative to bridge this supply gap.”

Group1 notes that potassium is more than a thousand times more abundant than lithium, and its KBW cathode is produced using low-temperature sustainable processes.

Development began small with a coin-cell battery, then progressed to a pouch-cell format and now the world’s first 18650 KIB has been unveiled. This format should mean relatively easy deployment to electric vehicle manufacturers, as well as potential use in power banks and portable gadgetry, for the promise of “the best combination of performance, safety, and cost when compared to LiFePO4 (LFP)-based Li-ion batteries and sodium-ion batteries.”

The new cells operate at 3.7 volts and are reported to have exceeded performance expectations, demonstrating “a practical path to achieve a gravimetric energy density of 160-180 Wh/kg.” Though this is up there with typical LFP packs currently in the wild, it still lags behind the next-gen CATL Shenxing Plus batteries – which top out at 205 Wh/kg. In a straight performance shootout, it’s even farther behind the lithium batteries in the lab as well as 4680 cells found in Tesla’s electric vehicles, for example.

Group1 has sent out samples to “key Tier 1 OEMs” and battery cell manufacturers, aiming for “widespread adoption of this transformative technology” in the very near future.