Fire safety is a fundamental requirement for rechargeable batteries, especially in large-scale energy storage. Yet despite this, we have not eliminated the risks in liquid flammable electrolytes. Scientists from Chinese Academy of Sciences just announced a clever battery with onboard firewall. Could this be the much needed break through we have been waiting for.
How Does the Onboard Battery Firewall Work?
The press release from Chinese Academy of Sciences we link to below, speaks of a ‘self-protecting, non-flammable electrolyte that physically blocks thermal runaway in sodium-ion batteries’.
They go on to confirm this is the first time this has been achieved in high capacity cells. Apparently, the liquid electrolyte in the battery ‘automatically solidifies’ when the temperature becomes greater than 150 ºC / 300 ºF.
This clever battery with onboard firewall is therefore a step away from flame-retardant electrolytes, that resist the reaction. Instead, this innovation appears to emphatically prevent a fire spreading.
This mechanism causes the electrolyte to undergo a ‘rapid phase change’. In terms of this, the solidified electrolyte ‘effectively cuts off the propagation of heat’. And prevents the catastrophic fires or explosions typically associated with battery failure.
What Else Do We Know About This Firewall?
This is exciting news, although the Chinese Academy of Sciences is thin on detail. The research was completed with sodium-ion batteries, which they continue to see as the natural successor for lithium-ion chemistry.
Therefore, as New Atlas explains, the research was done on a sodium ion-based battery using a ‘polymerisable non-flammable electrolyte’.
This combination coped with internal heat up to 300 ºC / 575 ºF, while delivering a respectable 210 watt-hours-per-kilogram energy density.
Interesting Engineering wraps up the story by predicting this discovery could lead to rapid adoption of sodium-ion batteries. This might in turn transform the landscape for electric vehicles and massive-scale energy storage.
More Information
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Preview Image: Safer Sodium-Ion Battery
Announcement on Chinese Academy of Sciences
