Reader Question: Hybrid Battery Saaaaaafety?

Here’s the latest reader question, along with my reply!

Teresa asks: You wrote about Telsa and fires recently. Are the same safety issues in the hybrid cars on the market? If someone owns a Telsa or hybrid that has battery safety issues, is there anything that can be done to the car to make it safer? Like encase the battery in something or some type of kill switch for the battery?

My reply: There is an inherent risk of thermal runaway fires with any lithium-ion battery, whether it’s in an EV, hybrid EV or a cell phone. However, the risk is lower with hybrids because there is less battery – because the battery only has to power the vehicle some of the time.

The hybrid’s battery pack is thus physically smaller – and so it isn’t necessary to spread it out over the entire length of the vehicle’s floorpan, as is usually the case with electric cars – in order to keep the battery pack from eating up too much trunk/interior room.

This means the hybrid’s battery pack is less vulnerable to physical damage in the event of an accident – and thus, to a fire caused by a short circuit (thermal runaway).

A “kill” switch would not make any difference in terms of the fire hazard because the issue/problem is the nature/chemistry of lithium-ion batteries. Thus, disconnecting the battery pack from the electric motors isn’t a solution to the problem. “Kill” switches are a great idea on gas-engined vehicles because they kill (turn off) the engine, which may still be running after a wreck and a potential danger.

A lithium-ion battery pack can be made safer – at the design stage – via making it more protected from being damaged by forces in a crash. But this isn’t a failsafe and it probably means more weight – and more cost – two problems EVs (and hybrids) already have their share of.

And it would not address the potential “wear and tear” issue – the fact that, over time, even the best-designed battery case (and battery within) will physically deteriorate just from aging, as well as jostling (i.e., a lifetime of hitting potholes).

All of the foregoing begs the question: Why do this at all?

Gas is abundant and inexpensive; gas engined cars are incredibly practical, efficient and affordable. What sound reason is there for abandoning them in favor of less practical, less efficient, far less affordable – and more dangerous EVs?

It’s a question almost no one seems to be asking. The why not is worth thinking about.

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