Understanding battery fires

We live in an age when everything from smartphones and laptops to electric vehicles, forklifts and powered pallet trucks, even UPS (Uninterruptible Power Supply) systems run on stored power from batteries. Understanding and tackling the risk of battery fire enables you to charge equipment safely and help protect your employees, premises and operations.

What causes battery fire?

Batteries, particularly the rechargeable lithium-ion batteries commonly used in electric vehicles and personal electronics (such as the device you are using to read this), are safe during normal use but can pose fire hazards in some circumstances:

Overcharging 

If you charge for too long (or at the wrong voltage) it can cause the battery to rapidly overheat, a process known as ‘thermal runaway’.

Over-discharging 

When the battery is depleted beyond its critical level; this can also cause thermal runaway.

Exposure to heat

High temperatures, including prolonged exposure to direct sunlight, could cause battery failure and fire.

Physical damage 

If the battery is punctured or has a manufacturing defect, it may cause an internal short-circuit which could ignite the electrolyte solution.

How can a battery cause an explosion?

When batteries become damaged or overheated, an internal chemical reaction can cause the electrolyte solution within the battery to break down. This process releases hydrogen gas which, when mixed with oxygen, forms a highly volatile and combustible mixture. If the area is not adequately ventilated, hydrogen can build up and increase the risk of explosions and fires.

What can I do to prevent it?

Overcharging 

Always use the correct charger supplied or recommended by the manufacturer, ideally one that shuts off automatically once the device is fully charged. Don’t charge batteries overnight, or leave them unattended whilst charging; monitor the temperature and stop charging if necessary. Ensure you have adequate and regularly-tested smoke detection and fire suppression systems in place.

Over-discharging 

A Protection Circuit Module, or PCM, will protect against this, and extend the life of the battery.

Exposure to heat 

Store and charge batteries in a cool, dry, well-ventilated location, away from sunlight, hot environments, heat sources and flammable materials. Good ventilation is crucial to help prevent the build-up of the gases caused by electrolysis, so charge forklifts in an open area wherever possible. Alternatively, consider fitting a dedicated LEV extraction above the charge point to remove any hydrogen.

Physical damage 

Source batteries from reputable manufacturers and suppliers. Store batteries safely away from sharp objects or heat sources and do not puncture or compress them. Implement routine inspections of battery systems, including visual checks for signs of damage or deterioration, and schedule periodic maintenance to address any issues promptly and pro-actively. 

IMPORTANT: If a battery is overheating, emitting smoke or is swollen or leaking, shut down the device and remove the battery safely if possible; follow your company’s reporting procedure and dispose of the battery at a designated recycling point.

Are there specific risks associated with large battery charging?

Several industries have environments and large battery charging processes which could lead to hydrogen formation and therefore risk of explosion; these include data centres and server farms, electric vehicle manufacturing and charging stations, multiple forklift/pump truck charging banks and renewable energy storage systems, such as wind farms and battery manufacturing and recycling facilities, 

Can I get expert advice on my business?

A Dangerous Substances and Explosive Atmospheres Regulations (DSEAR) assessment covers all aspects of battery management including charging, storage and handling to identify potential sources of hydrogen generation and ignition. It helps identify and assess hazards and recommends ways to mitigate them to ensure a safe working environment. 

How to Take Action

If you're looking for more information or a no-obligation quote, our Risk Solutions Team is here to help you. 

Contact us at 01427 420 404 or risksolutions@skaltd.co.uk to learn more about how exposure monitoring can safeguard your employees and ensure compliance.