June 20, 2025: US lithium battery tech developer 24M has unveiled what it described as a breakthrough electrolyte that enables ultra-fast charging and “unparalleled” performance in extreme cold temperatures.

The company said on June 18 its ‘Eternalyte’ electrolyte marked a step change with up to three times the ionic conductivity of standard electrolytes, said to significantly increase performance without compromising energy density, regardless of the chemistry.

Resulting in a charge rate four times higher than a conventional electrolyte, Eternalyte can deliver 300+km of additional range in under four minutes (charging from SOC 15% to 80%), the company claimed.

Crucially, 24M said the ultra-fast charging capability does not require a mega-watt charging infrastructure either.

And where conventional batteries lose about 25% of their capacity at 0°C and almost all capacity at much lower temperatures, 24M claims Eternalyte electrolyte retains essentially all capacity at 0°C and more than 80% capacity at -40°C.

Although initially designed for lithium metal batteries, 24M said Eternalyte can also be used for silicon and graphite-based batteries. The firm said it can be integrated into existing manufacturing processes and, when used with 24M’s Impervio separator tech, can deliver a fundamentally safer, long-lived battery.

Naoki Ota, president and CEO, said the innovation tackled some of the key challenges facing the use of lithium ion batteries.

He said rapid charge, superior low-temperature performance and great cycle life with lithium metal and other high energy density chemistries, Eternalyte provides outstanding performance for applications ranging from EVs to consumer products.

“It paves the way for next-gen batteries, including lithium metal, with 1,600km driving range and years of reliable performance.”