Tiny computers could keep EV batteries from crapping out when one cell dies
Perhaps along with the fact that they don't allow for thousands of miles of travel on a single charge, electric vehicle batteries do have a shortcoming – they're only as good as their weakest cell. That's because all their 100-plus cells are connected in series, meaning that if one of them dies, then the whole battery pack stops working. That could be about to change, however, thanks to research being carried out at Germany's Fraunhofer Institute for Manufacturing Engineering and Automation.
In a prototype system developed by Fraunhofer, each cell within a battery has its own microcontroller that monitors parameters such as temperature and charge level. All of these processors communicate both with one another, and with the vehicle's central onboard computer.
In this way, if an individual cell loses power while the others are still well-charged, it's simply shut off and "uncoupled" so that the current bypasses it. This means that the vehicle can keep going, using the electricity stored in the other cells – ordinarily, this wouldn't be possible.
Drivers are still made aware of the faulty cell, however, so they can have it (and only it) replaced at their convenience. By contrast, if it were a conventional battery pack, the whole thing would have to be replaced.
Not only should the technology make EV batteries more dependable and longer lasting, but it could also lower their price. This is because cells of slightly varying capacities could be used, with no one cell throwing off the capacity of the battery pack as a whole. Ordinarily, cells of exactly the same capacity must be selected, which drives up production costs.
The company is currently working at miniaturizing the technology.