24M, a US company, has released a new technology that is expected to solve the problem of electric vehicle battery fires

Electric vehicle battery fires are not uncommon. Although statistically less likely than internal combustion engine vehicles, when a battery fire occurs, it can continue to burn for hours or even days, sometimes without obvious signs, which can lead to some dangerous situations.

But the battery industry isn’t sitting idle – innovation is always happening, and the latest discovery from US startup 24M could be one of those industry-changing breakthroughs. Called the Impervio battery separator, it prevents overcharged batteries from catching fire, significantly improving safety.

The Volkswagen Group-backed startup released a video showing two 10 amp-hour lithium-nickel-manganese-cobalt-graphite batteries fully charged and then at 100 percent overcapacity. Overcharging a battery can lead to dendrite formation and internal short circuits, which can cause a fire or explosion.

The bottom cell was an off-the-shelf cell, while the top cell was equipped with 24M’s Impervio separator, and the results spoke for themselves. The stock cell caught fire about 38 minutes into the testing procedure, reaching temperatures of 293 degrees Fahrenheit, while the 24M-built cell with Impervio separator remained stable throughout the hour-long test, never exceeding 86 degrees Fahrenheit.

“Battery safety is a major barrier to electric vehicle adoption. Recent electric vehicle fires around the world highlight why new battery safety innovations are needed,” said Naoki Ota, President and CEO of 24M. “A sustainable energy future is only possible with innovations like Impervio, which can help prevent battery fires and create new opportunities for battery innovation.”

24M said its separators prevent dendrite growth by controlling the battery at the level of individual electrodes. This extra layer of safety prevents thermal runaway by monitoring the battery’s electrochemistry and implementing fault protection in the event of a potential short circuit, 24M added.

The Cambridge-based startup is not the only one working to reduce the risk of battery fires. A few days ago, LG Chem unveiled a temperature-responsive “safety enhancement layer” for its batteries, which changes its resistance depending on the temperature, effectively acting as a “fuse” that stops the flow of current at the early stages of overheating.

It would be nice if these innovations could magically be put into practice sooner rather than later, but the reality is that it will take at least a few years for 24M and LG Chem’s solutions for preventing battery fires to become standard in electric vehicles.