taking charge of ebike battery safety

Mar 06, 2023

Les Day, UK Regional Sales Manager for asecos Ltd, talks through some of the considerations and best practices when storing eBike batteries…

RISKS

The major problem with lithium ion batteries is the so-called Thermal Runaway. This is a process that starts in one cell of a battery, leading to a temperature increase that causes the cell to disintegrate and suddenly release its stored energy.

This release of energy creates a domi­no effect, causing adjacent cells to also disintegrate, releasing more energy and temperature increases. This chain reac­tion can be very unpredictable – a slow smouldering fire with occasional flare-ups or a rapid fire / explosion.

Are there warning signs that a battery is a risk? Not always, but the main ones to look out for are:

Apart from that, a battery that takes longer than normal to charge or fails to fully charge can also be taking as warning signs.

REGULATIONS ALREADY IN PLACE

At the moment, there are no specific regulations for the storage and charg­ing of batteries.

For the time being, we have to rely on organisations such as the Fire Protec­tion Association, the RISCAuthority and the Fire Industry Association who have issued general guidance documents.

The London Fire Brigade have also put together a good guide. See: www.london-fire.gov.uk/safety/lithi­um-batteries/

A Private Members Bill was tabled in the Commons last September but this was more to do with industrial battery storage. It was due to have a second reading last month but this is now delayed until next November.

COMPLIANCE

Without legislation there is very little to say on compliance. All you can suggest is "good practice" such as:

Handling and Use:

CHARGERS & CHARGING PRACTICE

STORAGE

DISPOSAL

IMPACT ON LIABILITY (INSURANCE)

Many insurance companies, such as AXA, Zurich, Allianz etc. are alert to the dangers of lithium ion batteries and are starting to advise clients that they need to look at sae storage / charging. AXA, in particular, have warned of the dangers posed by lithi­um batteries in e-bikes and scooters.

SOLUTIONS

Many companies have approached us, not necessarily from the eBike sector, informing us that their insurance advi­sors, fire inspectors etc. have instructed them to purchase cabinets that provide 90-minutes fire resistance, for storing and charging their Li-On batteries.

Whilst there are numerous 90-minute cabinets available, these usual­ly meet the EN14470-1 standard and are thus certified to provide fire resis­tance from the outside in. However, as the risk is with the batteries them­selves, they actually require a cabinet that provides fire resistance from the inside out i.e. cabinets that have dual certification, for example EN14470-1 and EN1363-1.

asecos product is available to the UK cycling trade via Madison.