ITEM: One of the problems with electric vehicles is that charging them takes way too long. Quantum batteries could fix that, says a new paper.
EVs have always had to match the experience of traditional gas guzzlers in order to be an attractive alternative. While they’ve been largely successful in terms of driving range and speed, it’s a different story when it comes to refueling. Using a gas pump takes a few minutes at the petrol station, but recharging an EV battery at a public charging station takes at least 30 minutes, while recharging at home takes hours.
The problem lies in the charging process. Batteries are comprised of cells – the more cells you have, the more energy you can store in them. Modern EV batteries are dense enough to hold a couple hundred cells, which gives them that extra range. The catch is that all those cells recharge in parallel and independently of each other. If you want to make the process faster, you need a way to charge the cells all at once.
Scientists from the Center for Theoretical Physics of Complex Systems within the Institute for Basic Science (IBS) reckon the answer lies in quantum batteries – which is to say, batteries that harness quantum properties such as entanglement that enables the cells to charge simultaneously.
The theory of quantum batteries has been around since 2012, but IBS published a paper in 2021 showing just how the process would work and how to design a quantum battery. From the press release issued this week:
The paper, which was chosen as an Editors Suggestion in the journal Physical Review Letters, showed that all-to-all coupling is irrelevant in quantum batteries and that the presence of global operations is the only ingredient in the quantum advantage. The group went further to pinpoint the exact source of this advantage while ruling out any other possibilities and even provided an explicit way of designing such batteries.
(To avoid confusion, note that “global operations” is the term for the technique of charging cells collectively.)
Interestingly, the paper also calculates how long it would take to charge quantum batteries. Basically, it would take about as long as takes to pump petrol into a regular car, or even less:
While the maximum charging speed increases linearly with the number of cells in classical batteries, the study showed that quantum batteries employing global operation can achieve quadratic scaling in charging speed. To illustrate this, consider a typical electric vehicle with a battery that contains about 200 cells. Employing this quantum charging would lead to a 200 times speedup over classical batteries, which means that at home charging time would be cut from 10 hours to about 3 minutes. At high-speed charging stations, the charge time would be cut from 30 minutes to mere seconds.
Obviously this is years away from ever becoming commercially available, but IBS reckons the applications for quantum batteries could extend well beyond EVs, from consumer electronics to fusion power plants of the future.
The paper is here.
The press release is here.