The news last week that Israeli battery technology firm StoreDot has developed batteries capable of powering an Electric car (EV) that could be charged in 5 minutes has been hailed by many as a game-changer (https://www.theguardian.com/environment/2021/jan/19/electric-car-batteries-race-ahead-with-five-minute-charging-times). For many EV sceptics, the thought that they might have to hang around at a charging point for an hour, reading the paper and having a cup of coffee is one of those that currently dissuades them from wanting to have an EV themselves, so a car that charges in 5 minutes could unlock that barrier. StoreDot have certainly attracted a lot of investment on the back of this idea.
But are they addressing the right problem? In fact there are EV batteries around already that are not far off these timings. First of all we should probably call out the fact that the article was not suggesting that StoreDot can fully re-charge an EV battrery in 5 minutes, only deliver enough charge to drive 100 miles, worth noting. The Porsche Taycan can already take a 150kWh fast charger and take enough charge to cover 100 miles in just 10 minutes. It probably won’t surprise people to know that the largest range batteries and those that can accept the fastest charging are not at the budget end of the market. They are made up of the likes of the Tesla Model S, the Porsche Taycan and the Audi E-Tron all with price tags above £80k. So before we get too excited that this technology, which StoreDot don’t envisage reaching the market for another four years, is going to revolutionise the uptake in EV’s any time soon, we should maybe think again.
Of course battery range and charging time will improve in time just as technology has improved the performance of the batteries in our mobile phones and laptops. But once more and more people start driving EV’s and are forced to by government policy, they may actually begin to change their priorities. In my experience, once people become EV car owners, whilst fast-charging remains a utopian dream, convenience and cost turn out to be equally important factors, if not more so.
That convenience means being able to charge your car when it best suits you, ie. when you are not needing to use it. That could be at home overnight on your driveway if you are lucky enough to have one, or in a parking area or on the street. This doesn’t need to be that fast and it can give you access to very low cost off-peak electricity. EV electricity tariffs from Octopus for instance allow you to charge your car for four hours a night at just 6p per kWh. Compare that to many public charging points which cost 45p per kWh and that is a perfect marriage of cost and convenience.
If you also find charging points at other destinations where you spend time anyway, then again, the time taken to charge becomes irrelevant, for example, at the supermarket, in the park and ride car park, at the shopping centre, the leisure centre, a restaurant or hotel, or at your favourite car park where you set off on dog walks from. The point is, the easier it is to charge your car while you are doing something else, the less of a concern super rapid charging, which we know will come at a price, will be.
So while the notion of super-rapid charging is attractive, I think we should be focussing for now on all the other innovations that will make charging EV’s more convenient. That might be the conversion of street lighting to make them double up as charging points, or apps like Bookmycharge that allow you to charge your car at someone else’s home, in much the same way that people rent driveways off other people to use as parking spaces.
In the meantime, did you know that in China you can already get from zero to a fully charged EV battery in less than 5 minutes? They have pioneered a battery swapping solution where you can get the whole car battery switched over at one of their Nio Power Swap stations. So in fact this problem has already been solved! https://www.caranddriver.com/news/a33670482/nio-swappable-batteries-lease/
So, was this news announcement the big deal it sounded like? I don’t think so. The technology is already there, it’s just peoples’ mindsets that we really need to change.
Neil Russell-Bates, Hilltop Sustainability