Storedot hails ‘extreme fast-charging’ silicon batteries

Israeli battery firm Storedot says its silicon-based cell, which allows for five-minute charging times, has received “very positive” feedback from prospective clients. Storedot, established in 2012, plans to license this technology – rather than manufacture and sell complete cells – to automotive partners including the Mercedes-Benz Group, Ola Electric, Polestar, Vinfast and Volvo. It claims its unique chemistry allows for a 100-mile charge in five minutes. It's targeting 100 miles in three minutes by 2028 and cutting that down to two minutes within a decade. Storedot CEO Doron Myersdorf told Autocar Business that the company began supplying test cells to manufacturers in September. He said: “On the cell level, the feedback is very good. Everything that we said is repeatable.” Storedot boasts of an energy density of 300Wh per kg – greater than the 260Wh/kg figure reported by CNBC for Panasonic’s type-2170 cell, used in the Tesla Model 3. Storedot cells have now completed 1000 full ‘extreme-fast’ (350kW) charging cycles, not degrading within the first 600 but losing 20% capacity after “more than 1000”, according to an official statement. Yaron Fein, Storedot's vice-president of R&D, said: “I'm delighted to announce that not only have we achieved our target but have also exceeded it – and we already have in our labs enhanced formulation that allows us to show further improved performance. “This is the first time ever that cell performance of this magnitude has been achieved.” However, there are significant hurdles to overcome before the technology is ready for production in 2024. The most challenging, Myersdorf told Autocar Business, is thermal management. “There's cooling in the vehicle, [but] it's mostly designed for the discharge," he explained. “In a Tesla, when you go into Ludicrous Mode [for unrestricted performance], there's a lot of heat on the discharge. We're creating very similar heat while charging.” Compounding the difficulty is that a car is parked while charging, so there's no air flowing through the radiator as there is with a car in motion. Myersdorf continued: “It's not like it used to be with people looking for plug-and-play solutions. It's not the case any more because more people are realising that this is an [integral part] of the vehicle.” Storedot’s success will also rely on whether the infrastructure can adapt to charging at a rate of 350kW or faster – creating demand for its battery technology. “It’s a chicken-and-egg problem,” said Myersdorf. “Until we [developed] this solution, people didn't think that they would be able to push 350kW-plus. "BP, for example, didn't see that coming. The reason they invested [in Storedot was] to be part of this ecosystem, because they understand that they need to repurpose their fueling stations to charging stations.” Storedot’s claims are yet to be scientifically peer-reviewed, although the firm had been granted 68 US patents as of 1 June 2022, with a further 27 pending approval.