Liquid and solid-state batteries have their advantages and disadvantages, but the team at the University of Texas at Austin claims to have found new batteries that combine the benefits of both. The team said it was the first fully liquid metal battery that could work at room temperature, and that the performance was significantly better than that of conventional lithium-ion batteries.
The electrodes of common liquid metal batteries are made of liquid metal, and the advantage of a solid-state battery is that it does not form a dendrites, thus damaging the battery assembly. And the battery is very easy to scale up, just adding more liquid to the larger jar.
But one drawback of a liquid metal battery is temperature. In order for the metal to remain liquid, most of these batteries need to be heated to a minimum of 240 degrees C (464 degrees F). Doing so can make the battery bulky and energy-hungry.
In the latest study, the team found alloys that can remain liquid at room temperature. They identified two well-working alloys, using sodium-potassium alloys as anodes, and argon alloys as cathodes. The batteries are able to remain liquid at temperatures of 20 degrees C (68 degrees F), which the team says is the minimum operating temperature of all all fully liquid metal batteries.
The two liquid metal electrodes are separated by the organic electrolyte in the middle, which is also liquid. The team says the new battery can charge and discharge several times faster than lithium-ion batteries and has a high energy and power density. The team says that as temperature barriers are removed, it is possible that new liquid metal batteries will begin to power electronics of all sizes, from small wearables to power storage systems on the scale of the grid.
Yu Ding, lead author of the study, said, “This battery offers all the benefits of solid and liquid — including more energy, greater stability and flexibility — without their own disadvantages, while also saving energy.” “
Nevertheless, there is much room for improvement. The price of radon is a bit expensive, so the team plans to study alloys made from other, more common materials. Some of these other materials may also allow the battery to operate at a lower temperature. More conductive electrolytes can also help increase power output.
Source: University of Texas at Austin