EV fleets and depots: overnight charging is your biggest fire risk

Electrifying a fleet is a win on cost and emissions. It also concentrates a lot of lithium-ion energy in one place, often charging overnight, unattended, in a shed or yard full of vehicles. That's the scenario worth planning for.

Fire and Rescue NSW is recording lithium-ion fires at a rate of several a week and rising (Fire and Rescue NSW [FRNSW], 2024), and the national ports body has warned that our systems for responding to large battery fires are still catching up with the technology (Ports Australia, 2026). Fleets sit right in that gap: real concentration of risk, response frameworks still maturing.

Where the fleet risk actually concentrates

It isn't usually the vehicle on the road; it's the depot at 2am. Many EVs, e-bikes, e-scooters and cordless tools charging together, unsupervised, means one failing pack can spread to its neighbours before anyone knows. Add mixed chargers, damaged packs returned from the field, and tight parking, and a single fault becomes a facility fire.

What operators should put in place

• Know your volume and duty. In NSW, sites using, handling or storing 25,000 kg or more of lithium batteries must lodge an emergency plan with Fire and Rescue NSW, but the underlying work health and safety duty applies at any volume (FRNSW, n.d.).
• Design the charging area. Charge on non-combustible surfaces, with spacing between vehicles and packs, away from exits and the building where practical.
• Control the chargers. Standardise on compliant chargers and remove damaged or swollen packs from service immediately, isolated in fire-resistant containment.
• Detect and train. Smoke and heat detection in charging areas, and drivers and yard staff trained to spot the warning signs.
• Plan the response. A clear plan for when to stop, evacuate and call 000, plus equipment positioned near charging points to contain a small, early fire.

The fleets that come out of the transition well are the ones that treated charging infrastructure as a fire-safety project, not just an electrical one. Plan the depot, control the chargers, train the crew, and the overnight risk becomes a managed one.