Lithium-ion Battery Safety
by Fiona Nelmes
Lithium-ion (Li-ion) batteries, or LIBs - with their high efficiency and compact design – have revolutionised energy and are now a familiar component in the automotive world. However, with great power comes great responsibility and - due to their thermal instability - improper storage and handling of these batteries can result in leaks, overheating, thermal runaway (a chain-reaction caused by overheating, overcharging or mechanical damage that generates excessive heat and flammable gasses - which can lead to fires or explosions - often leaving behind toxic materials as a result.)
With incidents on the rise, insurers Allianz recently highlighted the importance of reviewing storage, handling and transport of LIBs – found not only in Electric Vehicle batteries but also many portable hand tools in the workshop. With unique challenges to overcome that pose a risk of potentially-devastating consequences, safe processing of LIBs is crucial for the safety of personnel, the environment and businesses.
Although there are currently no specific regulations or legislation covering the safe storage of lithium-ion batteries in the UK, we are moving toward stricter safety oversight with the proposed Lithium-ion Battery Safety Bill, which outlines provisions that:
Planning authorities consult safety agencies before approving battery energy storage systems;
Devices powered by lithium-ion batteries meet stricter safety standards;
Guidelines are implemented for the safe disposal of lithium-ion batteries.
While formal legislation is still in development, the Health and Safety Executive (HSE) has provided guidance on best practices for handling and storing batteries. Storing lithium-ion batteries specifically follows similar principles as the correct storage of chemicals. According to the HSE, employers are expected to:
Ensure batteries are stored in cool, dry and well-ventilated areas, ideally between 5°C & 20°C;
Ensure proper disposal of batteries in authorised recycling facilities;
Provide appropriate PPE for working with batteries;
Provide training to employees on safe battery handling, storage and use.
In addition, we recommend further proactive management measures, including:
Maintaining 40-60% charge level for batteries in long-term storage, regularly checking their status and recharging to optimal range if it has dropped below 20%. Storing fully charged or entirely depleted batteries can strain cells, increasing the risk of degradation or failure;
Use non-conductive, fireproof lithium-ion battery storage containers or specialist battery cases away from metal tools to minimise the risk of short circuits and fires;
Keep terminals clean and free from dust/debris to maintain optimal performance and safety,
Avoid leaving batteries in areas prone to temperature fluctuations, such as near radiators, in direct sunlight or cold garages during winter;
Always store batteries away from flammable or combustible materials to reduce the risk of fire spreading in case of an incident.
Avoid storing loose batteries together, as their terminals may come into contact and cause a short circuit.
Regularly inspect batteries periodically for signs of damage, swelling or corrosion. Isolate any damaged batteries in accordance with the Battery Supplier’s instructions and arrange for their safe disposal ASAP if these issues are present, to limit the time a battery is stored on site.
We are expecting the requirement for all batteries to be individually stored in specialist cases to become mandatory in the near future. For now, we are limited our recommendation for these cases only to be required in damaged/end of life batteries (see below) but we expect this to change shortly.
Damaged* and End of Life Batteries
*In addition to visual signs such as dents, scratches or expansion, a battery is also considered damaged if:
Ø dropped 30cm or higher
Ø is involved in a crash at 20mph or higher;
Ø is punctured by a sharp object.
Treating battery damage as an emergency is essential in fire prevention. Generally, if a worker is ever concerned about a battery, they should notify their designated Health and Safety Officer immediately and where appropriate, the emergency services.
Batteries requiring disposal are dangerous waste and should be assessed for suitability to transport by a qualified battery expert at the earliest opportunity:
A green battery is a high voltage battery (HVB) that has been assessed as "safe for transport" by a competent person with specific qualifications (e.g. training) based on the manufacturer's assessment protocol.
A red battery is one assessed as "not safe for transport" by a competent person with special qualifications (e.g. training). A battery of this type has different requirements for transport to reduce the risk of an incident in transit.
If a battery is classified as unsafe, a quarantine zone should be set up and only personnel trained in the safe handling of Lithium-Ion Batteries should handle them until they are passed to an approved disposal contractor.
In order to be safely transported, BAM certified safety battery boxes for unsafe batteries will be required. These boxes are large and heavy, so space must be considered and lifting aids are likely to be required to move them on site. These should be stored at least 10 metres away from buildings and people, and should be enclosed in either non-conductive fireproof storage containers or be kept in an isolated area with a concrete wall surrounding them.
Unsafe and end of life batteries require specialist transport, therefore, disposal contractors should be selected based on meeting the requirements of Standard UN38.3. This standard consists of tests and criteria for the safety of lithium batteries (stand-alone or installed in devices) in transport.
You must provide documentation to the disposal contractor including Dangerous Goods related documents: Material Safety Data Sheets, COSHH Assessments and Manufacturer Protocols. The disposal contractor must provide you with certificates detailing information that uniquely identifies each battery being transferred: Battery Identification, Part Number, Vehicle Identification Number (FIN/VIN), Dealer Name & Address, Dealer Number, Time and Date.
The ADR Agreement sets out the international Carriage of Dangerous Goods by Road with regards to packaging, load securing, classification and labelling of dangerous goods. Adherence to these protocols ensures proper information is conveyed to emergency services, transport personnel, and others who may come into contact with the goods. You should ensure your disposal contractor meets these obligations.
Emergency Preparedness
For businesses handling lithium-ion batteries, having documented procedures, staff training and ongoing consultation for what do in the event of a battery malfunction, damage or fire is of paramount importance. In addition to regularly-reviewed policies and procedures, manufacturer training, Toolbox Talks and frequent refresher training should be provided.
For further insight, this topic was recently discussed at an online event hosted by the Institute of Occupational Safety & Health (IOSH) with speaker Gillies Crichton, Managing Director of Resilire Assure Ltd, a recording of which can be viewed on YouTube here
Look out for our regular blogs and if there are any subjects you want to see included, let us know at info@kvf-consultants.co.uk
