Nikkei. Fuji Heavy Industries (FHI) has developed new rapid recharge technologies that can recharge its R1e electric car to 80% capacity in approximately 8 minutes—twice as fast as before.
FHI plans to commercialize the Subaru R1e in 2010, and hopes to further reduce the recharge time to about five minutes, so that the car cab be recharged as quickly as a regular car can be refueled at the pump.
The R1e runs off a set of 16 battery modules, each assembled from 12 lithium ion cells. Since lithium ion batteries cannot withstand overcharging very well, care must be taken when recharging, and the current must be reduced once a certain overall voltage is reached even if some modules are slower to recharge than others.
To speed up recharging, the company built a microcontroller into each battery module to monitor voltage at both terminals of each cell. This not only allows recharging with a large current, but also enables the batteries to be charged up to 90% capacity with the rapid charger. This extends the R1e’s range on a single charge to 72km, up 8km.