Plus aluminum cells only carry 40 watts of electricity per kilogram compared to lithium’s 100 to 206 W/kg power density. “Improving the cathode material could eventually increase the voltage and energy density,” said Dai. “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."
I found that almost hilarious. "Yeah, five times less energy density, but otherwise perfect and totally going to kill lithium ion."
I wonder if it's better suited for large scale energy storage? Cheaper materials, improved safety, and longer cycle life may be worthwhile, even at the expense of storage density, as that might be less important in a static setting like that?
Edit: Ah, they actually mention that application in the Stanford article linked elsewhere in the comments.
Charge times, safety, and cycle durability are important. Even if direct competition with Li-ion is absurd at this point, the comparison isn't useless as it gives context.
For example, if you compare to Lead-acid [1], it has about twice the energy density and is probably less harmful to the environment. Also, 7000 charge cycles is excellent compared to existing types.
Note though that in addition to charging quickly, not deteriorating quickly, being bendable, and not being a fire hazard it's a prime candidate for wearable batteries that can be used in conjunction with in-device batteries.
I know many people who already have taken to wearing portable usb battery packs whereever they go, to the point that their clothing is designed around that use case.
A max 40 Wh/kg is ridiculous. For comparison, I have some Li-ions that are 260 Wh/kg. They say that the main advantage is the 7x number of charge cycles, but if your aluminum battery weighs seven times more for the same capacity you could literally carry seven equivalent Li-ion batteries (!) and just change which one you use to get 7x the charge cycles.
I found that almost hilarious. "Yeah, five times less energy density, but otherwise perfect and totally going to kill lithium ion."
Yawn.