GM said Friday that its investigation into recent battery
fires involving the cars found that manufacturing defects in a certain battery
cell were the root cause. It is asking owners of 2017-2019 model year Bolts to
keep their electric-vehicle charges at a certain level and to park the cars
outside after charging them.
Under the previous recall, initiated in November, owners of
69,000 Bolts were advised to get a software update that would monitor the
condition of the lithium-ion battery and flag any potential problems. Customers
began receiving those software updates in the spring, a GM spokesman said.
GM has since learned that at least one battery fire occurred
in a vehicle that had received the software update, the spokesman said. The
company is aware of eight fires total and two related injuries but no deaths,
he said.