Read the smoke signals

E-vehicle fires call for comprehensive policy action

India’s policy thrust to encourage the uptake of green e-vehicles may be affected by safety concerns after several recent incidents in which e-scooters have caught fire, causing panic and loss of life. While the government has ordered an enquiry, it cannot be content to simply identify and patch lacunae in technology.

The authorities must review and reorder the road-safety ecosystem. As the number of e-vehicles in service rises, the fire brigade and the police will need to be retrained, and, maybe, issued new equipment. In addition, if the policy is not to be derailed by consumer hesitancy, the government must launch an outreach campaign to reassure citizens about the safety of this new class of green vehicles. While the statistics indicate that e-vehicles may be safer than internal combustion engines, the public must be convinced of this.

The scooter fires could have been caused by the unsuitability of imported lithium-ion battery packs for summer driving conditions. India is hotter in summer than most places where e-vehicles are popular, and the standard battery pack designed for North America or China is not tropicalised to withstand Indian summers. India is also a stressful driving environment, necessitating sudden acceleration/braking, which means a greater load on the battery pack, which therefore gets hotter.

A battery pack heated beyond a certain point can spontaneously combust. This can happen if a hot pack is recharged without a cooling-off period. It can happen long after a crash because of internal short-circuits, which are invisible to inspection. Indeed, a battery pack can reignite —due to invisible internal reactions — spontaneously 24 hours after the fire has been apparently extinguished. Battery fires burn hotter than petrol fires, and emit a combination of highly toxic smoke and flammable fumes, which can inflame nearby vehicles and structures. Packs designed to operate in cooler, less stressful driving conditions must be tested more stringently and, maybe, rejigged for India. If other technical factors are involved, those must be identified and addressed. The government may have to set new standards for battery packs, and warn users to wait for a cool-down before recharging.

However, over and above this, fire-hazards caused by an e-vehicle are different from those for which internal combustion engines are responsible. An internal combustion engine faces the danger of an electrical short circuit setting off an explosion of the fuel tank, as well as the danger of the fuel line, or the tank being ruptured in a crash, leading to flammable liquid or fumes leakages. In an e-vehicle crash, the delayed action factor means that the vehicle and/or its battery pack must then be isolated and observed. If there is a fire, it cannot be tackled easily. The foam used to smother petrol fires is ineffective. The advice is to detach the battery pack if possible, and to direct jets of cool water at it, until it cools and then it must be kept under observation. However, the fire department personnel, or traffic police, do not necessarily know this, or are even unaware of where the battery pack is usually located to access it.

India has just started rolling out e-vehicles (mostly two-wheelers), which comprise less than 1 per cent of the vehicles currently on the road. As green vehicles, including cars and buses, are adopted in larger volumes, the fire safety factor will acquire greater importance. Fire departments and police safety protocols must be updated to deal with them.