The Fire Risk of Lithium-ion Batteries

Battery fire is difficult to put out due to its self-sustaining nature. Taking away oxygen from the equation will further complicate the issue as the heating of the electrolytes will generate flammable gas. The formation of a flammable gas cloud is the precursor to an even worse outcome, an explosion.

There are two common reasons for lithium-ion battery fires:

• Structural damage / impact
• Overcharging

In the case that the batteries are physically damaged, the common outcome is electrolyte leakage. Electrolytes are commonly flammable liquid, and with the presence of oxygen, all the elements required for a battery fire are in place. If the internal compartment of the battery is compromised, a short circuit may occur and an instantaneous thermal runaway could happen, resulting in fire.?

Under normal operating conditions, the charging and discharge of Lithium-ion batteries will naturally create a passivating layer on the carbon. This formation process is exothermic (releases heat) and produces a small amount of flammable gas.

Overcharging can cause the temperature to rise over the recommended operating conditions. This results in the formation of flammable products and the battery exhibiting a self-heating behaviour known as thermal runaway.

Consequences of a Lithium-ion battery thermal runaway may include:

• Radiant heat: Battery electrolyte is a flammable liquid and will release a large amount of heat
• Toxic fume release: Fluoride or phosphate-based electrolyte will decompose at a high temperature and form toxic gases that spread in smoke for an extended distance
• Explosive over-pressure: In the event a flammable gas cloud is formed, explosions may occur, resulting in an over-pressure wave

As known industry leaders in the Energy sector, ACOR has undertaken detailed studies and modelling to understand the risk of a battery thermal runaway scenario. We can assist in preparing management strategies, targeting the likelihood and consequence of an event from the following aspects:

• Separation from nearby assets
• Spill or leak of electrolytes
• Fire management
• Asset life-cycle management

Want to know more?

Get in touch with our Energy team to understand how we can make your workplace safer.