Solid-state batteries and liquid-state batteries both have their own advantages and disadvantages. Researchers in Cockrell School of Engineering at The University of Texas think that they can have the best of both worlds with their new prototype battery. Their prototype both eliminates disadvantages and harnesses the advantages of both types, and perhaps most significantly, it also works at room temperatures.
Solid-state batteries, such as li-ion batteries, provide a sizable total capacity for energy storage, but they face deterioration over time depending on numerous factors like environment and usage habits.
Their liquid-state counterparts do deliver energy more efficiently, they deteriorate less over time, but their problem is that they require extra resources to keep them heated to stay liquid, usually above 464 degrees Fahrenheit (240 °C).
Electrodes in this new battery, however, can retain its liquidity at 68°F (20°C). This is a record low for liquid-state battery operation.
Yu Ding, a postdoc researcher in Guihuua Yu's team said “This battery can provide all the benefits of both solid- and liquid-state — including more energy, increased stability and flexibility — without the respective drawbacks, while also saving energy,”
As its anode, the battery includes a sodium-potassium alloy. The cathode part is a gallium based-cathode. The paper suggests that by utilizing different components, we may be able to get batteries with even lower melting points.
The researchers also say that this battery can deliver much more power in a given time, allowing for much faster charging potentially. Also, since the main components of the battery are liquid, scaling its size is much easier when compared to a solid-state battery. After all, bigger the battery, the more power it can deliver. So we can shape and mold such batteries to power anything from smartphones to at-home renewable energy infrastructure.
The research has been going on for more than three years now, yet it is still far from complete. Alloys used in this prototype are quite abundant when compared to those of solid-state components, so production scaling may not pose a big problem. Although, the gallium element poses a problem as it's a costly rare-earth element. The researchers deemed finding an alternative to it that can deliver the same performance a key challenge for their research.