Independent testing confirms Cuberg’s progress toward next-gen eVTOL batteries

June 17, 2020 | Press

This article orignally appeared in

Elan Head – The next-generation battery startup Cuberg has received independent validation of its lithium-metal battery technology, confirming an increase in specific energy of up to 80% relative to lithium-ion cells of comparably high power output.

Idaho National Laboratory tested Cuberg’s five-amp-hour battery cells on behalf of the U.S. Department of Energy (DOE). It determined the cells to have a specific energy of 369 watt-hours per kilogram at a discharge rate of C/20 (down to 303 Wh/kg at 1C), a specific power of 2,000 W/kg, and around 370 cycles with C/2 charging before the cells reached end of life at an 80% capacity cut-off. (Excerpts of the test results can be viewed here.)

After Cuberg receives the cells, it injects the electrolyte in-house, completes manufacturing and quality checks, then ships the cells directly to customers. “For the next couple years, we see this as the most efficient model, because it allows us to scale up very easily and maintain good quality control, and also competitive pricing,” Wang said.

Cuberg’s “secret sauce” has the additional advantage of being non-flammable, something that could prove to be a particular selling point in the high-stakes, safety-critical world of aviation.

“All historic electrolytes with lithium-ion batteries are made of organic solvents that are highly combustible,” Wang said. “[Our] more stable electrolyte allows it to be much more tolerant to abuse in different kinds of conditions.”

Wang said that over the past few months Cuberg has been ramping up commercialization “very aggressively,” and shipping samples to top electric aircraft developers around the world. Initial results have been encouraging.

“Right now we’re at a stage where many customers are testing our cells and starting to progress to the next stages in terms of co-development,” he said. “Our hope is that we’ll be able to work with some key customers to integrate our technology into their systems . . . and get to the point of maturity and performance where we can start actually doing full-scale system and even flight testing.”