As lithium-ion battery use grows, so do fire risks

Lithium-ion batteries power everything from smartphones to electric vehicles. Even if you primarily use a desktop computer, you’re still surrounded by them – smartwatches, digital cameras, robot vacuums, and more.

While essential to modern technology, they have made headlines due to occasional fires or explosions. Although such events are rare considering how widespread these batteries are, lithium-ion battery fires are nonetheless an emerging resilience challenge for global businesses.

To address these concerns, FM has developed a first-of-its-kind loss prevention data sheet for manufacturing and storing lithium-ion batteries. This comprehensive resource provides much-needed fire protection standards – something the industry has long lacked despite the rapid rise in lithium-ion battery use. While hazards exist, awareness of proper management and mitigation is limited, leading to misconceptions about their overall safety.

The data sheet represents the culmination of years of research, rigorous testing, and engineering analysis aimed at improving fire safety standards. FM engineers conducted real-world fire simulations at their research facilities, working alongside manufacturers, battery users, and other industry experts.

These large-scale experiments involved setting pallet-loads of lithium-ion batteries on fire under controlled conditions, helping researchers observe fire behaviour, heat release, and thermal runaway potential. Additionally, smaller-scale tests analysed the fundamental physics behind lithium-ion battery failures, allowing FM to pinpoint key risk factors and develop effective safety measures.

THE HIDDEN DANGER

Even if you only know a little about lithium-ion batteries, you’ve likely heard of thermal runaway – one of the biggest concerns associated with their use.

Thermal runaway happens when a battery cell has a short-circuit, setting off a chemical reaction that releases gases. This reaction can escalate rapidly, potentially resulting in a fire or even an explosion. Once it begins, it cannot be stopped, making prevention the best approach. The most effective way to contain it is by either removing the affected battery or using water to cool it down and stop the heat from spreading to nearby cells.

But what causes thermal runaway in the first place? In most cases, the batteries involved have experienced some form of physical damage – whether from being dropped, punctured, or overcharged.

Occasionally, defects during the manufacturing process can weaken a battery, making it more vulnerable to failure. In other instances, a fire in one battery can trigger a chain reaction, causing others to overheat and enter thermal runaway.

Despite these risks, most lithium-ion batteries in everyday devices never experience any issues. Most phones, laptops, and other battery-powered products function safely without incident. The ones that do catch fire or explode have most likely been damaged or mishandled in some way.

FIRE PROTECTION IN FOCUS

The storage and handling of lithium-ion batteries are as varied as the products they power. The level of fire risk depends on multiple factors, including charge levels, packaging, and overall storage configuration. Properly managing these factors can significantly impact fire prevention and containment.

For instance, a warehouse storing power tools with built-in lithium-ion batteries poses a relatively low fire risk. These batteries are encased within the tool’s protective shell, further secured in product packaging, and placed inside shipping boxes.

If the batteries are only partially charged to around 30% the chances of thermal runaway are significantly reduced. In the event of a fire, the outer packaging would ignite first, activating sprinklers before the flames could spread to the batteries themselves.

On the other hand, storing large quantities of loose lithium-ion cells, modules, or battery packs presents a much higher fire hazard. Without the protective casing and packaging, more batteries are likely to become involved in a fire, leading to rapid escalation.

To address these risks, FM’s data sheet outlines fire protection strategies based on key factors such as charge levels, ceiling and storage heights, and packaging materials. For example, it is recommended to provide a minimum of 10 feet of separation between lithium-ion battery storage and other combustibles. In high-risk scenarios, additional safeguards such as lower storage heights or in-rack sprinklers may be necessary to limit fire spread.

By implementing FM’s proven best practices, companies can strengthen their fire protection measures, minimise risks, and create a safer environment for manufacturing and storage operations.

Our data sheet is just the beginning. As research and engineering continue to evolve alongside this rapidly advancing technology, updates and refinements are already under way. With emerging risks and new challenges, our experts remain committed to staying at the forefront, ensuring businesses have the most up-to-date guidance for lithium-ion battery safety.

Stephanie Thomas is senior staff engineering specialist and Benjamin Ditch is principal research engineer at FM.