The race is on to build batteries for electric and hybrid cars that charge faster, costs less, and have greater energy density. Now, scientists at Stanford say they have invented a new aluminum-ion battery that does 2 of those 3 things.
Lithium-ion batteries are what most manufacturers choose for their electric and hybrid cars today. But lithium has some drawbacks. First of all, it is in relatively short supply, which makes it expensive. Lithium-ion batteries also have a bad habit of bursting into flames when punctured and operate at extremely high temperatures. That’s why lithium-ion batteries need heavy shielding and built-in cooling systems, both of which add cost and weight to the finished product.
Hongjie Dai, a professor of chemistry at Stanford, explains why his breakthrough is better. “[L]ithium batteries can go off in an unpredictable manner – in the air, the car or in your pocket. Our new battery won’t catch fire, even if you drill through it.” But that’s not the real news. The aluminum battery Dai and his colleagues are working on at Stanford can be recharged in as little as 1 minute. It can also go through 7,500 discharge cycles without losing capacity. Lithium batteries have a useful life of only 1,000 discharge cycles.
Let’s think about that for a moment. Instead of Nissan LEAF owners fretting about how many bars are showing on their battery status meters, batteries could outlast the car they are fitted to. Instead of sitting in a rest area for an hour waiting for your EV battery to recharge enough to get you to the next charging station, you could zip in and get a full battery charge in less time than it takes to fill an ordinary car with gas.
Can you say, “Game change,” boys and girls?
OK. So is there a down side? Of course there is. “Our battery produces about half the voltage of a typical lithium battery,” Dai says. “But improving the cathode material could eventually increase the voltage and energy density. Otherwise, our battery has everything else you’d dream that a battery should have: inexpensive electrodes, good safety, high-speed charging, flexibility and long cycle life. I see this as a new battery in its early days. It’s quite exciting.”
It’s not all rainbows and sunshine though. I’m no battery scientist, but the top-rated comment on a reddit thread on this news from an actual battery scientist puts all of this hype in perspective for us;
First – the biggest issue will be a problem of scale. Ionic Liquids are expensive, and they don’t state what theirs is. First it has to be proven that this technology can be manufactured in larger sizes and in large quantities, and then you have to figure out how make the parts cheap enough to be viable.
The ambiguity is in the lack of specificity around the battery holding more charge. Is that by weight? By volume? Phone designs, for example, are built around the battery densities currently in use. Change that property by very much and you create new problems. Will this tech create phones that are a little thicker? A lot thicker? A lot heavier? Etc.
In other words, this isn’t a magic bullet for EV batteries…yet. Researchers have been trying for decades to make a commercially viable aluminum ion battery because aluminum is less expensive and more plentiful that lithium. It is also more stable and more environmentally friendly. Will it be decades more before aluminum ion batteries move out of the lab and into production? Possibly, but then again, we may be on the cusp of a breakthrough.
If Dai and his colleagues can pull this off, suddenly the green car revolution could shift into high gear.