Scientists solve battery mystery – allowing for ultra-fast charging breakthrough

Anthony Cuthbertson
Mon, 30 January 2023 


Scientists say they have finally figured out how to overcome a major barrier to ultra-fast battery charging.

The mysterious short circuiting and failure of next-generation lithium metal batteries was solved by a team from Stanford University and SLAC National Accelerator Laboratory in the US, who said their findings could have major implications for the electric car industry.

Rechargeable lithium metal batteries are lightweight, inflammable, hold a lot of energy and can be charged very quickly, however until now they have been unsuitable for commercial use due to mechanical stress experienced while charging.

“Just modest indentation, bending or twisting of the batteries can cause nanoscopic fissures in the materials to open and lithium to intrude into the solid electrolyte causing it to short circuit,” said Associate Professor William Chueh at the Stanford Doerr School of Sustainability.

“Even dust or other impurities introduced in manufacturing can generate enough stress to cause failure.”

The phenomenon has puzzled researchers for years, with some hypothesising that it was due to the unintended flow of electrons, while others claimed it was a chemical issue.

The Stanford scientists undertook a series of 60 experiments to prove that the problems were in fact caused by nanoscopic cracks, dents and fissures within ceramic electrolytes.

“Given the opportunity to burrow into the electrolyte, the lithium will eventually snake its way through, connecting the cathode and anode,” said Geoff McConohy, who used to work in Associate Professor Cheuh’s lab but now works in industry. “When that happens, the battery fails.”

The research was detailed in a study, titled ‘Mechanical regulation of lithium intrusion probability in garnet solid electrolytes, published in the scientific journal Nature Energy on Monday.

Germany's Vacuumschmelze agrees binding deal with GM on magnet factory


Mon, 30 January 2023 

LONDON (Reuters) - Vacuumschmelze (VAC) has agreed a binding deal with General Motors to build a North American factory to make rare earth permanent magnets for electric vehicles, the privately held German company said on Monday.

The agreement finalises a memorandum of understanding the two companies announced in December 2021, a statement said. No financial details were provided.

The factory to make rare earth permanent magnets needed for EV motors is expected to open in 2025 and supply a wide range of GM models, including the Chevrolet Silverado, Cadillac Lyriq and the Hummer, it added.

Rare earths are a grouping of 17 metals that, after processing, are used to make magnets found in EV motors that turn electricity into motion.

VAC, the largest producer of rare earth permanent magnets in the Western hemisphere, said the factory will use locally sourced raw materials and support GM for a minimum of 10 years.

GM has said that it could produce up to 2 million EVs globally by 2025, the year when it expects that EVs will make money for the company.

(Reporting by Eric Onstad; Editing by David Goodman and Jane Merriman)