Lithium-ion BatteryDo you have equipment powered by Lithium-ion Batteries, they can be a fire risk?

Lithium-ion batteries have been blamed for several incidents that have occurred in Australia where property has been damaged. Other countries are facing similar issues. This post is to highlight these issues. This is not to say that all lithium batteries are dangerous, but the batteries have the potential to be a risk.

The Lithium-ion batteries must be handled with knowledge, care and the correct equipment. Much the same way that we handle petrol when filling adding it to a fuel tank.

Issues with Lithium-ion Batteries

Lithium-ion batteries are susceptible to heat and structural damage that may lead them to heat uncontrollably and start a fire. This has been described in articles as a “Thermal Run-Away” where the heat generated leads to further failure which leads to more heat, exponentially. This is not ‘new’ news as it has been #discussed as early as 2013. Lithium cells are generally safe and have been designed with various inbuilt safety measures.

The batteries have pressure-sensitive vent holes, separator serves as a fuse, Positive Temperature Coefficient (PTC). However, if damaged they can still overheat and possibly catch fire if one of the safety features are not fully effective.

Several gases can be generated during the failure stage, and some are flammable. A mix of gasses including carbon monoxide; carbon dioxide methane and hydrogen make up the greater proportion of gasses generated when a battery fails. These gasses by themselves are flammable and will present breathing hazards in the immediate area when ignited.

If the Lithium-ion batteries have a manufacturing defect or design flaw. Abnormal or improper usage that may be because of a charger issue or even low-quality components. The best course of action is to stand clear and let the fire burn itself out however if the fire is in an enclosed area. If there is a risk that the fire can spread to other plant or a building, this is not suitable.

Safe Charging Lithium-ion BatteriesĀ 

Safe charging processes and understanding how the Lithium-ion batteries work can assist in elevating the risk.
Some of the key issues that will assist in safe charging a lithium battery are:
– Ensure that the battery has high grade cells from known manufacturers.
– The charger should of a type that can monitor the battery temperature as part of the charge cycle. If the battery gets too warm, then the charger should shut off.
– The charger should be of a type that will stop charging when batteries are just off 100%. This will assist in reducing the risk and increase the battery life.
– Lithium batteries are not to be left on a permanent charge. Once charged the battery is to be disconnected.
– Never charge a battery that has been compromised in any way. Mechanical damage or water ingress for these types of batteries may increase the risk of failure with little warning.

Further considerations to improve safety when charging lithium-ion batteries

– Choose an external location away from buildings and other plant to charge batteries.
– Park electric powered vehicles at a safe distance from each other. This way should an issue arise either the vehicles can be safely separated from each other.
– Use a fireproof cabinet, (example, an old chemical storage container) to charge multiple small batteries. There will need to a vent in the cabinet should a battery fail to ensure that the container does not pressurise.

Responding to a fire in lithium-ion batteries

– Fire blankets will assist if the fire is evolving. Parts of the battery may be expelled (explode) and there is a risk of a secondary fire. This is a short-term control on a small fire.
– A CO2 fire extinguisher can be used to cool the battery, but battery fires can easily reignite, so it may not be worth wasting the extinguisher.
– A F-500 Extinguisher is stated as being suitable for lithium-ion battery fires. This extinguisher is water based so you will need to disconnect the charger before using the extinguisher. The manufacturer states that it ‘performs extraordinarily well on combustible materials that output extremely high temperatures’.

This post was to make readers aware that there is a risk associated with Lithium-ion batteries. These batteries are used in most rechargeable hand tools and other rechargeable items like scooters and buggies. There is a risk that a damaged battery can fail and cause a fire that is difficult to extinguish.

Sources of information for Lithium-ion Batteries
#The European Association for Advanced Rechargeable Batteries