While we all may want to poke fun at Samsung as being a big customer of the "self-extinguishing" Lithium Ion battery, the fact is that there were a lot of device this past year; including hoverboards - that had fire related issues caused by poor batteries or poor overall design. The batteries use a polymer shell in the heart of each battery that melts when it gets too hot. Inside this shell is a fire retardent chemical. Poof. Problem solved. It's actually so simple it's ridiculous.
Similar solutions using TPP within lithium-ion batteries have been trialed before, though in those cases TPP was mixed directly with the electrolytes inside the battery itself, degrading performance to an impractical level. In this latest example, it's unclear how much space is used inside the battery at this stage, and whether this will have a significant impact on battery performance, possibly making it an impractical solution in small form devices like mobile phones or tablet computers.