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Fri, Feb

Silicon-air battery achieves running time of over 1,000 hours for the first time

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Silicon-air batteries are viewed as a promising and cost-effective alternative to current energy storage technology. However, they have thus far only achieved relatively short running times. Jülich researchers have now discovered why.

In theory, silicon-air batteries have a much higher energy density and are also smaller and lighter than current lithium-ion batteries. They are also environmentally friendly and insensitive to external influences. Their most important advantage, however, is their material. Silicon is the second most abundant element in the Earth's crust after oxygen: it is cheap and its reserves are practically inexhaustible.

Silicon-air batteries are viewed as a promising and cost-effective alternative to current energy storage technology. However, they have thus far only achieved relatively short running times. Jülich researchers have now discovered why.

In theory, silicon-air batteries have a much higher energy density and are also smaller and lighter than current lithium-ion batteries. They are also environmentally friendly and insensitive to external influences. Their most important advantage, however, is their material. Silicon is the second most abundant element in the Earth's crust after oxygen: it is cheap and its reserves are practically inexhaustible.

However, the silicon-air battery does still have a few crucial blemishes: for example, the flow of current stops after a relatively short period of time. Only assumptions have been made thus far as to why this is the case: does a protective layer form spontaneously on the silicon anode? Is the electrolyte at all suitable? Is there a problem with the air electrode? Attempts to rectify this problem by improving the components have proven to be less than successful. The best result was achieved through the use of a special, high-quality electrolyte based on an ionic liquid. This helped increase the battery's running time to several hundred hours, but contradicted the fundamental idea of the battery: to provide a cost-effective alternative to lithium-ion batteries.

Continue reading at ScienceDaily

Silicon-air battery Image via Forschungszentrum Jülich