1,36,000 litres of water used to put out Tesla EV fire! How solid-state batteries can redefine safety

With the electric vehicle landscape expanding globally, EV fires have become a topic of concern and discussion for potential customers and the industry stakeholders. Well, even when there’s a lot going on behind the curtains and manufacturers are spending heavily on R&D to enhance the safety of EV batteries, some incidents bring it back to square one.This time, a Tesla Model Y caught fire on the night of Christmas, leading to the closure of an interstate highway in Alabama. Emergency services arrived at the scene and had to use a staggering 1,36,000 litres of water over an hour to put out the fire.
Even in India, where there has been a robust growth for the segment in the last 2-3 years, incidents of vehicle fires have been posing a major roadblock in the path of a full-fledged adoption.
Why is it hard to douse off EV fires involving conventional lithium-ion batteries?
Unlike traditional ICE (Internal Combustion Engine) vehicle fires, it is relatively very hard to douse EV fires. In fact, putting out fires in EV batteries is really tricky. When an EV battery catches fire, you can’t just use water to stop it, like you would with regular fires. The fire can trigger something called “thermal runaway,” where one fire can make other battery cells get too hot and catch fire too. Even after the fire is out, the battery can get so hot that it starts another fire minutes or even hours later in some cases.

What are solid-state batteries? Why are they safer as compared to conventional lithium-ion units?
Unlike a lithium-ion battery pack that uses liquid electrolytes that are flammable, solid-state batteries replace these flammable liquids with solid electrolytes. The absence of liquid electrolytes significantly reduces the risk of fire. At present, there are companies like QuantumScape, Stellantis, Hyundai, Volkswagen and Toyota that have been working on the technology. In fact, Toyota, a pioneer in the space, has secured over 1,000 patents for its solid-state batteries that uses sulfur-based electrolytes in the prototype version.
What more? Toyota says that the solid-state batteries, besides reducing the chances of fire, also have comparatively higher energy density. That means, the solid counterparts of liquid electrolytes can hold more charge and will require lesser space. In simpler terms, it will help in increasing the range of vehicles substantially.
What are the drawbacks?
Designing a solid electrolyte that is both stable and performance-capable while maintaining efficient ion conduction between electrodes is a challenging task. Additionally, these batteries are costly to manufacture as it requires much more lithium as compared to the conventional li-ion batteries. However, as the technology progresses, we can be optimistic that with time, maybe in the later 2020s, companies will cumulatively find a way to bring the production cost down and bet on solid-state batteries as a safer, more capable alternative to what we are using right now.