Faulty battery link to storage unit fire - report

A large fire at a storage unit in Surrey was probably caused by a faulty battery, a report has said.

The blaze in May 2023 at Access Self Storage, in Byfleet, caused plumes of smoke to be visible for miles.

A heavily redacted report by the South East Fire Investigation Group into the incident said the investigation had concluded "that the most probable cause of fire was a defective lithium-ion cell" in a unit on the second floor.

Access Self Storage said its insurers had processed 80% of claim forms received and settled 73%.

Surrey Fire and Rescue Service said it could not comment on the report due to "potential" legal cases.

The report - which has been seen by the BBC - said the defective cell may have caused a "thermal runaway", which spread to other lithium-ion batteries in one of the units.

A thermal runaway is an accelerating increase in temperature caused by chemical reactions which can "lead to fire, explosion... and unpredictable fire behaviour," according to the National Fire Chiefs Council.

The South East Fire Investigation Group report concluded that the fire had "spread rapidly" to "combustible materials" within the same unit before spreading to other units.

It said that firefighters noticed a unit roller shutter was padlocked after entering the depot and had to leave to collect bolt croppers.

When they returned "the intensity of the fire [had] increased significantly".

An Access Self Storage spokesman said it had received more than 800 calls and fielded 5,200 emails to customers, as well as sending regular updates via emails and a dedicated website page.

“Surrey Fire and Rescue Service concluded that all of our processes and policies were satisfactory, and Access Self Storage was not found to be at fault for the fire,” he said.

“We are focused on remaining in the local community to support businesses and residents with a new facility.”

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