Lithium-ion batteries are currently one of the biggest problems in the tech world. The ubiquitous power source has an annoying tendency to burst into flames. But researchers at Stanford University believe they may have found a solution with a built-in flame retardant that doesn't harm the battery's performance.
The Li-ion battery is great for holding a charge and fitting into small devices, but sometimes it experiences what's called "thermal runaway". The term refers to an exponential growth in heat. The battery contains two primary electrodes — the anode and the cathode. If these electrodes touch each other, thermal runaway can kick in and that's when people suddenly find themselves with a flaming pocket or worse.
The solution that scientists at Stanford are offering involves separating the electrodes with a flame retardant. Engadget explains the technical details:
Usually the separator is a boring polymer like polyethylene, the world's most commonly used plastic. The new separator consists of fibrous threads of triphenyl phosphate (TPP), a common flame retardant, with a shell of another polymer (PVDF-HFP). The polymer shell prevents the TPP from seeping into the electrolyte, which would reduce the battery's performance.
When the separator hits 160 degrees Celsius, the polymer melts, abruptly releasing the TPP into the electrolyte and extinguishing the combustion.
So far, this has only been tested in a coin cell and further experimentation will be required to know if the flame retardant works in larger batteries like a smartphone or even an electric car.
Battery fires and related product recalls have affected Apple, Tesla, hoverboards, electric skateboards and most famously Samsung. This kind of innovation could save companies big money but it also may remove an impediment to innovation. With proper safety precautions, it's possible that thinner batteries will be more feasible in the future.