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How Can You Stop Batteries From Catching Fire? Perhaps by Adding Some Water
The quest for water-based batteries that are difficult, or impossible, to set on fire has attracted millions of dollars in government funding, as well as backing from global investors and power companies lured by manufacturers’ claims of not only improved safety but also lower costs.
Water hasn’t been used in lithium-ion batteries’ electrolytes—a component that is key to both the charging of the battery and the release of electricity—because the high voltage common in those batteries can pull water apart into oxygen and highly flammable hydrogen. That high voltage is needed for small, light lithium-ion batteries to provide sufficient power for devices like electric vehicles, small appliances and electronic devices.
But so-called long-duration batteries, such as those destined to store energy generated by solar panels or wind farms, don’t need to be small or light. That means lower voltages can be used, making water-based electrolytes viable. It also means metals that are heavier and cheaper than lithium can be used.
“The cost factor of course is important to our customers and that’s usually the first thing that hooks them. But it’s also not flammable,” says Thomas Nann, chief executive of Australia’s Allegro Energy, a maker of water-based batteries. Australia’s largest power company, Origin Energy, has taken a 5% stake in Allegro and is about to start a trial of the Allegro battery.