The inventors of a lithium-ion battery concept that releases its own built-in flame retardant say it could reduce the flammability of smartphones and other mobile devices without sacrificing battery performance.
The concept, published last week in the journal Science Advances by a team of Stanford University researchers, uses the relatively cheap triphenyl phosphate as a flame retardant.
"With this smart and adaptive material in the battery, we do not have to make a trade-off between the electrolyte nonflammability and the electrochemical performance of the battery," the researchers wrote.
In theory, their concept is fairly simple and doesn't require a lot of added sensors or electronics. If a battery experiences a "thermal runaway," the increased temperature would cause its protective polymer shell to melt, exposing the flame-retardant layer and preventing combustion.
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The team notes that it is not the first to take on the problem of lithium-ion combustion, which has prompted engineers to suggest everything from encasing the battery in ceramic to including a layer embedded with sensors that detects abnormal heat. Using a heat-sensitive shell to encase cheap retardant works better, however, because it would require minimal changes to existing battery design.
Despite their ubiquitousness in consumer electronics, experts have warned that lithium-ion batteries could be dangerous in certain situations. They caused a fire that contributed to the crash of an Asiana Airlines flight in Korea in 2011, and are a prime suspect in the series of fires and explosions that caused Samsung to recall its Galaxy Note 7 smartphone last year.
Samsung still has not announced the official cause of the fires, with a spokesperson telling the BBC this week that it is "working diligently to ensure that we have a comprehensive update and will provide more information in the coming weeks once we have the final report."