BATTERY FIRE SUPPRESSION SYSTEM

A fire suppression system for a battery pack includes a controller, an inlet line, an outlet line, a detector, a first pressure vessel with a first valve, and a second pressure vessel with a second valve. The pack includes: an inlet, battery modules housing battery cells, and an outlet. The inlet line connects to the pack inlet and the outlet line connects to the outlet. The detector senses a condition indicative of a fire event caused by a battery cell breaking and produces a signal. The controller, connected to the detector, determines a fire event is occurring based on the signal. The first vessel and the second vessel connect to the inlet line. A first suppressant flows from the first vessel into the pack when the controller opens the first valve. A second suppressant flows from the second vessel into the pack when the controller opens the second valve.