Energy Storage Fire Protection Solutions

Once a lithium-ion battery overheats in a BESS and the process of “thermal runaway” occurs, it can be nearly impossible to extinguish, potentially causing catastrophic damage and risking the lives of first responders called to put out the fire. 

Awareness of the abuse factors listed below can help operators prevent thermal runaway at its earliest stage.

Electrical Abuse

This occurs when a battery exceeds voltage limits during charge or discharge and overheats. The simultaneous operation of these batteries poses the risk that any one of the battery cells could exceed voltage limits during charge or discharge and could cause overheating that triggers a potential fire event.

Thermal Abuse 

This is initiated when the operational temperature exceeds the limits of the battery. If caused by overcharging, the extra current triggers a chemical reaction that breaks down the battery’s organic liquid electrolytes and changes them from a liquid to a highly flammable gaseous state.

Mechanical Abuse 

This can be caused by physical or mechanical damage to the battery, such as a crush, indentation, or puncture from vibration or shock.

When an abuse factor occurs or continues undetected and unaddressed, more of the liquid electrolyte from the battery will convert to gas, causing an internal buildup of pressure sufficient to vent or rupture the battery seals and resulting in an off-gassing event. Eventually, as more gas is generated, internal pressure and heat continue to increase, rupturing, melting the separator, and releasing smoke. By this point, thermal runaway or fire is imminent and can no longer be stopped. The failure of a single cell can quickly overheat and spread rapidly to surrounding cells, leading to thermal propagation. The earliest possible detection of battery failure is vitally important to mitigate or prevent thermal runaway from starting and to maintain integrity and safety.