American company QuantumScape hopes next year to start pilot production of multi-layer solid-state lithium-metal batteries that will reduce charging time and increase the range of electric vehicles. At this stage, developers have managed to demonstrate the ability of existing prototypes to withstand several hundred consecutive fast charge cycles.
Express charging in this case meant recharging from 10 to 80% in 15 minutes for a prototype battery with characteristics close to the traction battery of an average electric car. Single-layer cells were used, tested in the temperature range from 25 to 45 degrees Celsius, the pressure rose to 3.4 atmospheres and the depth of discharge was up to 100%. Under these conditions, after 400 consecutive 15-minute high-current charge cycles that have restored the charge to 80%, the battery is could save himself 80% remaining capacity.
The types of lithium-ion batteries on the market with such intensive charging over many cycles in a row can lose their original capacity much more quickly after several tens of cycles. QuantumScape considers the ability to quickly replenish the traction battery charge as one of the factors contributing to the popularization of electric vehicles as they are now forced to sit idle at charging stations for at least half an hour. On average, owners of internal combustion engine cars fill up in five minutes, and the company’s solid electrolyte lithium-metal batteries can reduce the lag for electric vehicles to several minutes.
According to QuantumScape, an electric car with a range of 640 km, four hundred fast charging cycles, is enough to cover almost a quarter of a million kilometers. Recall that one of the main investors in this company is the Volkswagen Group, which by last year’s results has already become the second largest manufacturer of electric vehicles in the world. If such batteries find application in cars of related brands, then this will be a strong argument in the fight against increasing competition. Incidentally, previous representatives of QuantumScape made it clear that the batteries they developed are not only safer than conventional lithium-ion batteries in terms of fire hazard, but also better tolerate lower temperatures.