A vehicle includes a traction battery to propel the vehicle. The traction battery includes a plurality of cells that are each selectively connected to a resistor. A controller or controllers are provided that are configured to control the charging and discharging of the cells. The controller or controllers command the battery or a selected group of cells of the battery to discharge in response to a fault or triggering condition. The discharge enables the battery or the group of cells to achieve a state of charge of approximately zero or less.