Now, researchers from the Chinese Academy of Sciences are proposing a shockingly simple solution: batteries that simply cannot catch fire.

Their solution is a sodium-ion battery design that uses a polymerizable, non-flammable electrolyte that rapidly solidifies under extreme heat, forming an internal safety barrier.

Thermal runaway has long been a challenge in battery technology, especially in lithium-ion batteries, which typically use flammable electrolytes. The concern has received an even greater spotlight with the rise in electric vehicle (EV) usage, given the size of the batteries in these vehicles.

This phenomenon is a self-accelerating chain reaction wherein a battery enters an uncontrollable heating state. Once a certain temperature is reached, the battery's internal chemicals begin to react, releasing more heat. This heat then speeds up the reactions, creating even more heat in a vicious cycle. Within milliseconds or minutes, temperatures can skyrocket to 1,292-1,832 °F (700-1,000 °C). This often leads to the release of toxic gases, violent fires, or explosions.

What's more, because the battery creates its own oxygen during this reaction, traditional fire extinguishers often can't put it out. You usually have to wait for the battery to burn itself out. Thermal runaway can be triggered by a variety of conditions, including battery damage, overheating, overcharging, manufacturing defects, exposure to salt water, and external fires.

Sounds really scary, but do not fret. According to EV FireSafe, the chance that your EV will spontaneously combust due to battery issues is about 0.0012%. This figure is possible thanks to really advanced engineering and an immense amount of resources and effort.

Battery manufacturers spend years researching and designing every aspect of the battery, from cell chemistry to electrical architecture. This is usually followed by very precise manufacturing, then several rounds of rigorous testing. In addition to these factors, manufacturers design multiple monitoring, cooling, protective, and failsafe systems around the batteries.

All of these measures require literal years of effort and cost that could easily run into the billions of dollars. Therefore, you can understand why the researchers' proposed solution, a battery with an inherent fire prevention system, is a significant breakthrough.

Their system is a battery with a built-in smart firewall that automatically prevents potential fires before they start.