Torque Shop: EV fires can occur during improper charging

What can cause electric vehicle (EV) fires and what precautions can an owner take to alleviate the risk?

The EV is a new type of automobile. For more than 100 years, the world has known no better than the fossil-fuelled internal combustion engine (ICE). In comparison, the commercially available EV has barely been around for a decade, though its numbers are increasing in Singapore.

It is therefore hardly surprising that any news on EVs, especially of disasters, get a lot of attention in the media. Most of these occurred as the result of serious crashes, whether with another vehicle or something stationary such as a building, bridge structure or tree.

Such accident-related fires, however, are not unique to EVs, being hardly uncommon with ICE cars. Liquid fuel in the tank, especially petrol, is far more flammable than any battery.

In serious accidents, the combination of leaking fuel and hot exhaust can lead to fire.

Another common scenario resulting in fire is when an electrical short-circuit is in proximity to a fuel leak. The conventional ICE electrical supply may be only 12-volt direct current, but this is sufficient to cause ignition.

There has been news lately of EV fires due to the manufacturing defects of battery packs. While this is a cause for concern, such fires are not rampant and the EV manufacturers have been quick to rectify the situation.

Cases of fires at home while charging an EV or plug-in hybrid electric vehicles (PHEVs) are more common.

Using an extension reel to plug in the charger is a bad idea for a number of reasons. First, with every extension, there is an electrical connection, the quality and capacity of which are usually overlooked or perhaps even ignored by the vehicle owner.

There is also the issue of the type of wires used in the extension reel and its capability in supplying maximum current-carrying capacity for a continuous eight to 10 hours.

More often than not, unless specially made for vehicle charging, extension cables overheat and eventually burn up. After all, extension reels tend to be made for domestic appliances such as fans, stereo sets, routers and modems, which are low current or in use for relatively short periods.

Even when the charging cable is plugged directly into a 13-amp, three-pin socket, there are risks involved.

No one knows the standards of the domestic wiring in one’s home. Although rated at 13A, the wires that run through concealed conduits from the main circuit-breaker switchbox may be of average quality, making them insufficient for continuous duty.

It is always recommended that a dedicated EV charging wall box is installed at your home if you wish to charge your EV or PHEV overnight. Charging stations are purpose-built for EVs under strict rules and regulations. Overnight charging at these stations is not a problem.