UK study examines fire risks of lithium-ion batteries in e-bikes and e-scooters
The Office for Product Safety and Standards (OPSS) has published a report on the safety risks associated with lithium-ion batteries in Personal Light Electric Vehicles (PLEVs), such as e-bikes and e-scooters.
The study, conducted by Warwick Manufacturing Group (WMG), examined scientific literature, real-world fire incident data, existing regulations, and battery testing results.
It found that PLEV battery fires have increased in the UK, with incidents in London rising from two in 2017 to at least 178 in 2023, according to London Fire Brigade (LFB).
The research highlights concerns over manufacturing quality, battery management system (BMS) effectiveness, and consumer misuse.
Increase in PLEV battery fires linked to charging and quality issues
The report found that charging practices and battery quality are key factors in lithium-ion battery failures, which can lead to thermal runaway, fires, and explosions.
Analysis of LFB data showed that most PLEV battery fires occurred indoors, often while charging.
Some incidents involved the use of incompatible chargers with higher voltages than the battery’s specification.
The research also identified that conversion kits used to modify bicycles into e-bikes were involved in the majority of e-bike-related fires where the origin could be determined.
Battery inspections revealed that cheaper batteries often lacked critical safety features, such as temperature sensors, and had poor manufacturing standards.
In some cases, battery management systems failed to prevent excessive current and temperature levels, increasing the risk of thermal runaway.
Regulatory gaps and inconsistencies in PLEV battery safety
The report reviewed UK product safety regulations and identified inconsistencies in their application to PLEV batteries.
E-bikes and e-scooters with motors are regulated under the Supply of Machinery (Safety) Regulations 2008, which impose detailed health and safety requirements.
However, separately sold batteries, including those used in conversion kits, fall under the General Product Safety Regulations 2005 or the Electrical Equipment (Safety) Regulations 2016, which lack specific safety provisions for lithium-ion batteries.
The study also noted differences between e-bike and e-scooter battery safety standards.
While e-bike standards require compliance with stricter battery safety regulations, e-scooter batteries are subject to less rigorous requirements.
Recommendations for improving PLEV battery safety
The OPSS report suggests several measures to improve safety, including stronger regulations, improved standards, and enhanced consumer guidance.
Recommendations include introducing mandatory safety standards for all PLEV batteries, improving battery testing to account for real-world usage conditions, and enhancing consumer awareness about safe charging practices.
The study also highlighted the need for better incident data collection to inform future safety measures.
WMG noted that markets with stricter certification requirements, such as New York City and Singapore, have seen reduced incidents of battery fires following the introduction of safety regulations.
The report suggests that similar measures could help reduce PLEV fire risks in the UK.
London Fire Brigade Comment
Responding to the research, London Fire Brigade Deputy Commissioner Charlie Pugsley said: “This new independent research carried out by the Warwick Manufacturing Group reinforces the concerns that have been consistently raised by London Fire Brigade into the safety of e-bike and e-scooter lithium-ion batteries, chargers and particularly with conversion kits.
“The research, which was supported by our own substantial incident data, reaffirms the importance of introducing stricter regulation to reduce the risk of customers being exposed to dangerous products, particularly online.
“We hope the Product Regulation & Metrology Bill currently being brought forward will set a pathway for the necessary action to be taken to protect people from these types of fires and we are providing data and expertise to Government as we want to ensure the Bill is as strong as possible.”
Battery safety concerns highlighted in UK government report: Summary
A report commissioned by the Office for Product Safety and Standards (OPSS) has examined the safety risks associated with lithium-ion batteries in Personal Light Electric Vehicles (PLEVs), including e-bikes and e-scooters.
Conducted by Warwick Manufacturing Group (WMG), the study found a rise in battery-related fires in the UK, with London Fire Brigade (LFB) reporting an increase from two incidents in 2017 to at least 178 in 2023.
The report identified several factors contributing to fire risks, including poor manufacturing quality, inadequate battery management systems, and consumer use of incompatible chargers.
Testing of batteries revealed that cheaper products often lacked essential safety features, increasing the likelihood of thermal runaway and fires.
Regulatory inconsistencies were also highlighted, with some PLEV batteries subject to less stringent safety requirements.
The report recommends stricter regulations, improved battery testing, and better consumer education to reduce fire risks.
It also suggests learning from international markets, such as New York City and Singapore, where stricter safety measures have been implemented.