Lithium-Ion Battery Fires: Is Your Workplace Prepared?

Lithium-ion batteries are now part of everyday working life. They power everything from laptops and mobile phones to cordless tools, cleaning equipment, e-bikes, warehouse equipment and portable machinery.

For most businesses, these batteries are used every day without incident. However, damaged, poorly maintained or incorrectly charged batteries can create a significant lithium-ion battery fire risk.

The issue is particularly important for workplaces where several batteries are stored or charged together. Workshops, warehouses, offices, retail premises and facilities using rechargeable equipment should all consider lithium battery fire safety as part of their wider workplace fire safety arrangements.

Why Can Lithium-Ion Batteries Cause Fires?

Lithium-ion batteries store a considerable amount of energy within a relatively small unit. If a battery becomes damaged, overheated, overcharged or develops an internal fault, that energy can be released uncontrollably.

One of the main concerns is a process known as thermal runaway. This happens when rising temperatures inside a battery trigger chemical reactions that generate further heat. If the process continues, it can spread between individual battery cells and potentially lead to fire, explosion and the release of hazardous gases. Government guidance identifies thermal runaway, overcharging, short circuits and mechanical damage among the potential causes of lithium-ion battery fires.

Unlike many conventional workplace fires, a battery fire can develop extremely quickly. Lithium battery fires can produce intense flames and potentially flammable and toxic vapours, making them particularly challenging incidents to manage.

Where Could the Lithium-Ion Battery Fire Risk Be in Your Workplace?

The first step in managing lithium battery fire safety is identifying where batteries are being used, stored and charged.

Charging areas deserve particular attention. A single laptop charger may present relatively little risk when correctly used, but a dedicated area where numerous power tools, handheld devices or equipment batteries are charging simultaneously creates a greater concentration of potential ignition sources.

Businesses should also consider batteries contained within equipment rather than only loose battery packs. Common examples include cordless tools, mobile devices, cleaning machines, warehouse equipment, power banks, e-bikes and other rechargeable workplace equipment.

This is why lithium-ion battery fires should be considered as part of an appropriate fire risk assessment. UK workplace fire safety guidance requires the responsible person to identify fire hazards, consider who may be at risk and put appropriate precautions in place.

Warning Signs That a Battery May Be Failing

A damaged battery should not simply be placed back on charge.

Possible warning signs can include:

• unusual levels of heat
• swelling or changes in shape
• visible physical damage
• leaking
• unusual smells
• unusual noises or hissing
• changes in the way the battery charges or performs

London Fire Brigade advises users to stop charging a battery if it starts swelling or expanding and not to tamper with the equipment.

Businesses that regularly use battery-powered equipment should make sure employees know how to recognise these warning signs and understand what to do if damaged equipment is discovered.

Review How Batteries Are Being Charged

Battery charging safety should form part of day-to-day workplace procedures.

Where possible, batteries should be charged using the correct charger supplied or recommended for the equipment. Chargers should be kept in good condition, sockets should not be overloaded and equipment should not be covered while charging.

London Fire Brigade also recommends protecting batteries from physical damage and avoiding continuous charging once the charging cycle has finished.

For workplaces charging numerous batteries, it may also be worth reviewing where the charging area is positioned. Charging batteries beside combustible stock, within busy escape routes or in unsuitable storage areas could unnecessarily increase workplace fire risks.

Consider Whether Your Fire Detection Still Reflects the Risk

Workplaces often change faster than their fire protection arrangements.

A warehouse may introduce more battery-operated equipment. A maintenance team might switch from mains-powered tools to rechargeable alternatives. An office could install charging stations for multiple devices. Businesses may also begin storing spare batteries that were not present when the original fire risk assessment was completed.

When these changes occur, existing fire detection systems should be reviewed to establish whether they remain suitable for the way the premises are now being used.

UK Government guidance states that a fire risk assessment must be regularly reviewed and should consider fire detection and warning systems alongside other fire safety measures.

Businesses can also review the suitability of their existing commercial fire alarm systems as part of a broader commercial fire safety review.

Do Not Treat a Battery Fire Like an Ordinary Fire

A failing lithium-ion battery can behave differently from many other sources of fire.

Once thermal runaway has begun, the battery can continue generating heat internally. There can also be a risk of re-ignition and hazardous gases.

This makes staff training particularly important. Employees should not be expected to tackle a developing lithium-ion battery fire unless doing so forms part of an appropriate, professionally assessed fire safety procedure and they have received suitable training.

London Fire Brigade advises people confronted with a serious lithium battery fire to move to safety and call 999.

The priority should always be protecting people and ensuring evacuation arrangements remain effective.

Update Your Fire Risk Assessment When Your Workplace Changes

Managing lithium-ion battery fire risk is not simply about inspecting individual batteries.

Businesses should consider the wider picture:

• how many batteries are kept on site
• where they are charged
• whether damaged batteries are isolated appropriately
• whether charging areas are near combustible materials
• whether escape routes could be affected
• whether staff understand the risks
• whether existing fire detection systems remain appropriate

Under UK fire safety requirements, the responsible person must regularly review the premises’ fire risk assessment and maintain suitable fire safety measures.

If the number of lithium-ion batteries being used within a workplace has increased, this can be a sensible trigger for reviewing the existing fire safety arrangements.

Make Lithium Battery Fire Safety Part of Everyday Fire Prevention

Lithium-ion batteries are unlikely to disappear from workplaces. In many sectors, their use will continue to grow as equipment becomes increasingly portable, rechargeable and electrically powered.

The aim is therefore not to avoid battery technology, but to manage it properly.

Good battery charging safety, suitable storage, regular inspections and clear reporting procedures can help reduce the likelihood of lithium-ion battery fires. These measures should sit alongside appropriate fire detection, staff training and an up-to-date fire risk assessment.

If the equipment, charging arrangements or battery usage within your premises has changed, it may be worth reviewing whether your current fire protection measures still reflect the risks present on site.