Stanford University has developed a battery that charges completely in under a minute. The new battery that utilizes aluminum ions instead of the mainstream lithium-ion is more versatile and safe, assure the chemical engineers.
Stanford University scientists have invented the first high-performance aluminum-ion battery that’s charges super-fast, is long-lasting and most importantly, commercially inexpensive to produce. Researchers promise the new technology offers a safer alternative to many commercial batteries in wide use today. Extolling the virtues about the groundbreaking achievement, Hongjie Dai, a professor of chemistry at Stanford said,
“We have developed a rechargeable aluminum battery that may replace existing storage devices, such as alkaline batteries, which are bad for the environment, and lithium-ion batteries, which occasionally burst into flames. Our new battery won’t catch fire, even if you drill through it.”
It has been quite apparent for some time that the conventional lithium-ion batteries that are used in everything that needs a reliable rechargeable cell are struggling to meet our energy requirements. Large screen devices need larger batteries that still have to fit in the slim form-factor. However, merely increasing capacity isn’t a sustainable or viable long-term option. Moreover, lithium-ion batteries have a rather mundane and disappointing recharge-rate – the number of times one can charge and recharge the batteries before they die out.
Aluminum-ion batteries trump conventional lithium-ion batteries in every department, except voltage and capacity, but they make it up in endurance. While earlier iterations of aluminum-ion batteries failed after only about 100 recharge cycles, Stanford’s prototype can cycle more than 7,500 times without any capacity loss. That’s roughly 7.5 times longer than your average lithium-ion battery. “Your average cellphone battery will die after about 1,000 charge cycles, but this battery won’t”, exclaimed the researchers.
In its current stage, the aluminum-ion battery can produce only about 2 volts, far less than the 3.6V that lithium-ion can muster. Additionally, aluminum cells only carry 40 watts of electricity per kilogram compared to lithium’s 100 to 206 W/kg power density and that’s where additional research is required.
The team managed a breakthrough by swapping conventional cathode material with graphite, which is essentially a form of carbon that has the atoms arranged in a beneficial manner. However, the higher safety rating of the battery is due to the optimized design of the aluminum-battery. The Stanford team placed the aluminum anode and graphite cathode, along with an ionic liquid electrolyte, inside a flexible polymer-coated pouch, shared Stanford graduate student Ming Gong, co-lead author of the Nature study,
“The electrolyte is basically a salt that’s liquid at room temperature, so it’s very safe.”
Coming to the primary concerns of consumers: When will these aluminum-ion batteries hit the market and will they be affordable?
Interestingly, the team appears to be gearing up to first offer these batteries to replace your conventional 1.5 volt AA or AAA batteries, as their prototype can output 2 volts. So expect your miniature fitness equipment or electrical grid that needs a battery with a long cycle life that can rapidly store and release energy, to feature these aluminum-ion batteries in the next couple of years.
However, apart from the limited energy output, the aluminum-ion battery has everything else you’d dream that a battery should have: inexpensive electrodes, good safety, high-speed charging, flexibility and long cycle life.
[Image Credit | Mark Shwartz, Precourt Institute for Energy, Stanford University, PC World]