Lithium-ion batteries are everywhere - powering our smartphones, laptops, e-scooters, electric vehicles, and energy storage systems. Their usage has grown over time thanks to their high energy capacity, long life, and contribution to a greener future. However, there is a downside.
In February, CROSS published a Topic Paper to draw attention to the fire and explosion risks posed by lithium-ion batteries. This Paper recommended that everyone involved in the built environment stay up to date with the latest guidance and research.
What are the fire safety concerns with lithium-ion batteries?
At the heart of the issue is a phenomenon called thermal runaway. This is a chain reaction that can happen when a battery becomes too hot - perhaps due to overcharging, physical damage, or a short circuit. The battery generates heat faster than it can disperse it, and in rare circumstances this can lead to gas build-up, fire, or explosion.
While other types of battery can also experience thermal runaway, lithium batteries are particularly vulnerable due to their high energy density.
A fire involving lithium-ion batteries can escalate quickly, producing flammable gases, spreading rapidly, and potentially reigniting even after being put out. Common extinguishers don’t always work effectively, and water can make things worse by producing explosive gases like hydrogen.
Such risks have also evolved and expanded with wider usage and technology. Modern cars, for example, are made with more plastics and higher-powered batteries than vehicles from just a couple of decades ago. This means that if they do catch fire, they burn hotter and faster.
Lithium-ion battery safety in buildings
The good news is that these risks can be mitigated, if everyone involved understands them and adapts.
CROSS’ Topic Paper encourages those responsible for designing, building or managing buildings, including structural engineers, to read the latest research and take proactive action.
Such action could include the use of battery management systems which can prevent overcharging and overheating, or measures that ensure that batteries are properly stored in cool, ventilated areas away from flammable materials.
Buildings using or storing large numbers of lithium-ion batteries should also include specific fire safety plans. These might involve enhanced ventilation and appropriate extinguishing systems. Large battery systems should be treated as complex fire risks, particularly in places like underground car parks or buildings with energy storage systems.
For members of the public, the Topic Paper warns against second hand lithium-ion battery use in DIY projects. Such projects can introduce unregulated and potentially hazardous systems into your home (for example, DIY modified e-bikes or e-scooters). Don’t overload or overcharge batteries and avoid using damaged devices.
Research, reporting and guidance
A growing body of research is helping improve understanding. Projects like SafeBatt from The Faraday Institution are studying how batteries fail, how to detect the warning signs, and how best to respond.
The Topic Paper also points to guidance from the Fire Protection Association, the Office for Zero Emission Vehicles, and NHS Estates that offers practical safety advice for different settings, from hospitals to homes.
Engineering and fire professionals are encouraged to add to this growing body of knowledge by confidentially reporting safety concerns or near-miss incidents involving lithium-ion batteries to CROSS.
Lithium-ion batteries are widely used and integral to modern technology. They offer many advantages, including long lifespans and are key to enabling renewable energy storage.
By working together and sharing knowledge, we can ensure lithium-ion technology continues to benefit society - without putting people or buildings at unnecessary risk.
For more information and to read the full Topic Paper, visit the CROSS website.