The global electric vehicle (EV) market has grown exponentially over recent years, with numbers on the road only set to continue rising, as we drive for sustainable alternatives to traditional fuel sources to support our greener future.
However, this is also bringing greater safety risks, and should these vehicles become damaged (for example through a road accident), how they’re stored and monitored by vehicle recovery operators and workshops is key to preventing further risk.
Tommy Carnebo, risk-management specialist Dafo Vehicle Fire Protection, discusses the risks associated with handling damaged EVs, explaining what can be done to prevent further damage and maximise safety.
Driving for a more sustainable solution
According to predictions, there will be more than 300 million EVs on the road worldwide by 2030, up from 16.5 million at the end of 2021, in line with global sustainability targets. This is as global leaders continue to push environmental agendas to reduce global carbon emissions.
Lithium-ion (Li-ion) batteries, which are constructed as an assembly of separate battery components (cells), power the majority of EVs. A specific electrical circuit connects and monitors each of these cells. Different types of vehicles may have different cell sizes and arrangements, which can affect the voltage and capacity of the batteries.
Presenting a new kind of fire risk
Regardless of their size or shape, Li-ion batteries (and thus EVs) present a special fire risk if they sustain any kind of damage:
- Li-ion batteries can malfunction internally as a result of physical damage, overheating, overcharging and overvoltage.
- This malfunction can cause the temperature of the battery cells to increase rapidly, and the battery to begin to emit smoke.
- These temperature increases, if not immediately managed, can result in fires, toxic emissions (such as hydrogen fluoride, carbon monoxide, carbon dioxide and cyanide), as well as large explosions.
‘Thermal runaway’ is the term used to describe this phenomenon. Once initiated, thermal runaway is exceedingly difficult to suppress using conventional fire-suppression techniques. And, as the number of EVs increases, so does the danger of thermal runaway.
The threat of thermal runaway is especially important for those operating recovery vehicles, workshops, mechanics or any other type of business that stores EVs after collisions or incidents. This is because thermal runaway can develop rapidly, for example, overnight when the EV is unattended and housed in a closed facility. This makes having a reliable fire detection and suppression system essential for maximising safety and preventing further damage to the vehicle itself, any valuable assets nearby and the environment.
Minimising risks and reducing quarantine time when storing damaged EVs
For traditional detection solutions, thermal runaway is often only identified after temperatures start to climb. At this point, those temperatures may be irreversible, and the hazardous gas released from the EV can seriously harm the skin and respiratory systems of anyone nearby.
Instead, EV batteries require a special fire detection solution, which measures carbon-monoxide levels to identify thermal runaway at the earliest stage possible, before temperatures rise.
A portable, sensor-based approach to EV fire safety – EV Guard
As EV accidents can occur nearly anywhere on the road, damaged vehicles occasionally require recovery vehicle operators to tow them for extended distances before storage.
This makes having a portable detection solution essential. A portable detection solution also allows for the application and repurposing of various vehicles’ systems, reducing costs.
This solution should regularly check the entire damaged EV for evidence of carbon-monoxide ventilation, which is an early indicator that the battery might eventually go into thermal runaway. The EV Guard system uses sensors – strategically positioned throughout the vehicle’s high-risk regions – to quickly identify any smoke emissions. It then sends an email message, a loud siren and flashing lights to:
- Make workshop teams or recovery personnel aware of the danger, so they can take the appropriate safety measures and evasive actions.
- Connect to the fire-alarm system at the location, so first responders can take the appropriate safety measures.
Creating a safer environment
To make sure thermal runaway is detected in its earliest phase, it’s essential to adopt a unique approach to fire safety for damaged EVs. This will:
- Shorten necessary EV quarantine periods following collisions
- Safeguard the work environment for workshop crews and recovery truck drivers.
For more information, visit Dafo Vehicle Fire Protection.
