Explosions

In a newly published study, we describe our design for a self-extinguishing rechargeable battery. It replaces the most commonly used electrolyte, which is highly combustible – a medium composed of a lithium salt and an organic solvent – with materials found in a commercial fire extinguisher. An electrolyte allows lithium ions that carry an electric charge to move across a separator between the positive and negative terminals of a lithium-ion battery. By modifying affordable commercial coolants to function as battery electrolytes, we were able to produce a battery that puts out its own fire. Our electrolyte worked well across a wide temperature range, from about minus 100 to 175 degrees Fahrenheit (minus 75 to 80 degrees Celsius). Batteries that we produced in the lab with this electrolyte transferred heat away from the battery very well, and extinguished internal fires effectively. We subjected these batteries to the nail penetration test, a common method for ass...

In today’s electronic age, rechargeable lithium-ion batteries are ubiquitous. Compared with the lead-acid versions that have dominated the battery market for decades, lithium-ion batteries can charge faster and store more energy for the same amount of weight. These devices make our electronic gadgets and electric cars lighter and longer-lasting – but they also have disadvantages. They contain a lot of energy, and if they catch fire, they burn until all of that stored energy is released. A sudden release of huge amounts of energy can lead to explosions that threaten lives and property. As scientists who study energy generation, storage and conversion, and automotive engineering, we have a strong interest in the development of batteries that are energy-dense and safe. And we see encouraging signs that battery manufacturers are making progress toward solving this significant technical problem. Avoiding overcharging is one way to reduce the ris...