Although lithium-ion batteries perform far better than alkalines, they're also relatively costly, the lithium salts used in them aren't widely available, and they sometimes catch fire. That's why some scientists are suggesting sodium-ion batteries as an alternative. To that end, Williams Advanced Engineering recently demonstrated that they could be used to power an electric bike.

The demonstrator bike was developed by British start-up Faradion, in partnership with Williams and Oxford University.

Its sodium-ion battery pack, which was made by Williams, incorporates sodium salts made from common salt. It consists of four 12-cell modules. The pack was made rather large, in order to keep costs and manufacturing complexity down, although Williams claims that a more refined commercial version would be similar in size to a lithium-ion pack of the same capacity.

Williams' communications manager James Francis tells us that the e-bike "performed well with no issues," although the demo (which took place this Thursday in a parking lot) wasn't extensive enough to get specs on factors such as range.

"Whilst lithium-ion is still the dominant choice of chemistry, sodium-ion is a fascinating alternative that could have real benefits in terms of cost and availability," says Williams technical director, Paul Mcnamara. "We have worked closely with Faradion and Oxford University to explore its potential and today was about showcasing the concept in a real world application for the first time."

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