New lithium battery ditches solvents, reaches supercapacitor rates

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Sabre
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New lithium battery ditches solvents, reaches supercapacitor rates

Post by Sabre »

Ars Technica

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One of them is a crystal with the rather complex formula of Li9.54Si1.74P1.44S11.7Cl0.3. This turned out to be very effective for high current applications. Another material, Li9.6P3S12, was better for high-voltage cells. Both of them were chemically stable, and neither involved any expensive raw materials. The authors determined their structure, which revealed that the new materials provided a three-dimensional grid, allowing ions to move in nearly any direction.

This may in part explain the new materials' improved properties, which include a conductivity twice that of their earlier solid electrolyte.

The authors built batteries that used these solid-state electrolytes and showed that the batteries could operate within a huge temperature range: -30 degrees Celsius up to 100 degrees Celsius. Commercial lithium-ion batteries don't function at either of the extremes of this temperature range. They also had a very fast charge/discharge capability, being able to complete a charge/discharge cycle in under seven minutes. At high temperatures, discharge rates were competitive with supercapacitors. The energy density (a weakness of supercapacitors) turned out to be competitive with that of lithium-ion batteries.

Because chemical reactions occur between the electrodes and this material when it is first run through a charge/discharge cycle, it loses some 10 percent of its capacity right at the start. But, after 500 cycles, it still retains 75 percent of the original capacity, indicating losses after that first cycle are relatively small.

Why is this solid electrolyte so high performing? It's structured so that it provides natural avenues for the lithium ions to travel along, and its three-dimensional mesh allows them to bypass any defects. And, within the solid, there are simply more lithium ions per unit volume than you can possibly get in a solution—over 20 times as many. Because the solid can't freeze and won't chemically degrade at high temperatures, it has a much higher operating range. Plus, it won't leak anywhere.
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I know a lot of people who would be very interested in this stuff. The temp ranges and the low capacity loss make this very attractive.
Sabre (Julian)
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Good choice putting $4,000 rims on your 1990 Honda Civic. That's like Betty White going out and getting her tits done.
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