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Inspiration can come from the strangest of places, but in the fast-paced world of electric car technology you might not expect it to come from one hundred years ago.
However, when the idea came from Thomas Edison you might be able to understand why scientists have given it another look.
The technology in question is nickel-iron batteries. As Science Daily reports, the technology was developed by Edison in the early 1900s to power electric vehicles, and remained in favor until the mid-1970s.
Since then, only a few companies have bothered with the technology, but scientists at Stanford University are giving it another go.
The appeal of nickel-iron is its durability and low cost, though the scientists are having to work around some of its drawbacks too.
"A typical battery can take hours to charge, and the rate of discharge is also very slow," explained Hongjie Dai, a professor of chemistry at Stanford. Neither characteristic is conducive to modern electric vehicles, which need to be charged quickly and supply enough energy for increasingly powerful electric motors.
And that's where the scientists have made the greatest improvements. Their new nickel-iron battery has been sped up by nearly 1,000 times--with their 1-volt demo unit fully charging in around 2 minutes, and discharging in 30 seconds. At the moment, it degrades over time just like a lithium-ion battery, but the team is working on improving that performance.
The team has used new technologies like graphene and carbon nanotubes to improve the transfer of electrical charges.
Dai suggests that when upscaled for electric cars, the battery might not have the capacity for powering a car itself, but could provide a backup to lithium-ion cells for extra power under acceleration, and greater storage from regenerative braking.
Century-old technology with a 21st-Century twist? If it works for the internal combustion engine...