A team of scientists developed a new type of aluminum battery that is cheaper, safer, and charges faster than the traditional lithium-ion one. Its developers claim that it can recharge in less than a minute and lasts longer than lithium-ion. However, it only provides nearly half the voltage.
Researchers hope that the new model will be soon used at a larger scale in smartphones and other electronic devices due to its advantages over alkaline and lithium-ion batteries. Yet, there are some scientists that claim that the work is still in a first stage so there’s no need for high hopes.
Hongjie Dai, senior developer and professor at Stanford University in California said that the new battery doesn’t burst into flames like lithium-ion batteries “occasionally” do, and it doesn’t harm the environment like alkaline batteries do.
Prof. Dai promises that the new battery “won’t catch fire even if you drill through it”.
Moreover, the aluminum battery is so sturdy that continues to work for a short period of time even after somebody drilled through it, which is impossible for lithium-ion batteries that are so hazardous that they were recently banned from air transport.
The battery is cheaper than traditional ones because it contains commonly used and inexpensive materials such as aluminum and graphite. For one electrode (the anode), the battery contains aluminum, while for the other electrode (the cathode), it contains a graphite foam.
The two electrodes are connected trough a liquid salt. Ming Gong, co-author of the discovery and PhD student, explained that the electrolyte is liquid salt at room temperature, which is safer than lithium-ion battery electrolytes that are highly flammable.
Scientists explained that the secret behind their prototype’s high charging speed is the graphite foam. The graphite foam acts just like a sponge that absorbs better the ions in the electrolyte and allows them to access faster the graphite.
When the battery gets almost empty, aluminum ions migrate from the anode into the spongy graphite structure at the cathode. When the battery recharges, the ions return on the anode. This cycle can be repeated about 7,500 times without any capacity loss, making the battery more durable several times than lithium-ion batteries, and hundreds of times than other aluminum-based prototypes.
Additionally, its two-volt output is considerably better than a 1.5-volt alkaline battery, and the best for an aluminum battery. Yet, it cannot compete with current lithium-ion batteries that power smartphones and laptops.
“Our battery produces about half the voltage of a typical lithium battery. But improving the cathode material could eventually increase the voltage and energy density,”
Prof Dai argued.
But the team already managed to charge a smartphone in a minute by strapping two aluminum batteries together and put them into an adapter. They also claim that their battery would come in handy in flexible displays.
Prof Dai stated that low voltage is the battery’s single drawback. On the other hand, it is safe, flexible, durable, inexpensive, and has speedy charging.
Clare Grey from the University of Cambridge was impressed with the clever way of storing charges inside the graphite, but expressed her concerns that turning the battery into a commercial product would be very challenging.
Image Source: Wonderful Engineering