The breakthrough technology works with lithium-ion battery chemistries of today, making it easy to mass-produce.
People would be much more likely to buy EVs if they could charge them up in about the time it takes to buy a cup of coffee at a charging station. A new lithium-ion battery reported in the journal in the journal Nature, promises that scenario. It can charge in just 10 minutes, without compromising the amount of charge it can hold, and could lead to EVs that run over 200 miles on a quick sip of electric power.
“We turbocharged proven energy-dense lithium-ion materials rather than relying on unproven, expensive chemistries,” says Brian McCarthy, chief technology officer at battery startup EC Power in State College, PA, and a co-author of the paper. EC Power is now planning to build a factory to start mass-producing the batteries, he says, adding that “our R&D department is working on decreasing the charging time to five minutes.”
Because today’s lithium-ion batteries take so long to charge—about an hour for a car to run between 300 to 350 miles—car and battery companies have been making larger and larger battery packs to reduce the need to charge often, and to overcome the problem of ‘range anxiety’. These massive batteries are expensive, and require more raw materials that are already facing supply chain issues.
A fast-charging battery could solve those problems. It would allow smaller batteries, which would be more affordable and sustainable, that could be charged in minutes, so that travel time remains the same. “Our technology will let automakers make more electric vehicles with the same quantity of materials,” McCarthy says. “We hope that our method will result in large numbers of truly affordable economy electric vehicles on the road.”
Researchers have previously attempted to make quick-charging batteries by tinkering with the materials used in the battery electrodes. But new electrode materials are not yet demonstrated to be cheap or long-lasting enough for mass use, he says.
So he, mechanical engineering professor Chao-Yang Wang of Penn State University, and their teammates instead decided to use a more economical method that regulates the heat inside existing battery technologies. They added an ultrathin nickel foil to standard lithium-ion batteries alongside the two electrodes. The foil self-regulates the battery’s temperature, allowing the reactions inside to happen much faster without overheating the battery, which translates to rapid charging.
The result is a battery that can charge up to 70 percent of its capacity in just around 10 minutes, and can do this 2,000 times in a row. Most previous attempts to make fast-charging batteries with standard materials have either given batteries that do not hold much total energy, or that cannot last for too many charging cycles.
The numbers attached to this are a bit vague, but using some assumptions, it leads to some interesting conclusions on the scale of the electricity supply required for the charging stations that might replace petrol/gas stations in time.
I took a charge sufficient to provide 50kWh that would be delivered in the time taken to get a cup of coffee and pay for the charge – I’ve assumed this to be 5 minutes but if 10 minutes then the result would be halved. Then thinking about my local petrol stations, about 10 charge points would be provided. If all in use the energy required would be some 30 MW. That’s a lot.