High performance potassium battery uses nonflammable electrolyte to build the next generation energy storage system
Australian scientists have developed a nonflammable electrolyte that can be used in potassium and potassium ion batteries to promote the development of next generation energy storage systems other than lithium technology. The new electrolyte is based on organic phosphate, which makes the battery safer and can operate at low concentration, which is a necessary condition for large-scale application.
At present, lithium-ion battery technology plays a leading role in the energy storage market. However, this kind of battery has inherent disadvantages such as price, environmental problems and flammable electrolyte. In developing the next generation of battery technology, scientists try to replace lithium ion with richer and cheaper materials such as potassium ion. However, there are also safety issues with potassium and potassium ion batteries, such as flammable electrolytes.
Zaiping Guo, a materials scientist at the University of Wollongong in Australia, and his team developed an electrolyte based on flame retardant materials and found a new solution. Triethyl phosphate is used as a single solvent component in the new electrolyte. Before testing in lithium-ion batteries, this kind of flame retardant material needs to reach a very high concentration in order to maintain stability for a long time, and the industrial application cost is too high. Therefore, the battery industry needs cheaper and better performance dilute electrolyte. In the course of the study, the researchers found that potassium ions could be used to reduce the concentration. They mix the phosphate solvent with a commonly used potassium salt to obtain an unburned electrolyte, which can make the concentration of the assembled battery stable at 0.9-2mol/l, suitable for large-scale applications, such as smart grid.
The formation of a uniform and stable solid-state electrolyte interphase layer is the key to ensure performance, the researchers said. According to their observation, only with this kind of phosphate electrolyte can interphase layer be formed, and traditional carbonate electrolyte can not form such layer. In addition, the new electrolyte has high cycle stability, but under the same conditions, the traditional carbonate based electrolyte will decompose.
The research team has proved that the new inorganic phosphate electrolyte can be used to manufacture the next generation of potassium ion batteries with safe performance. They believe that the electrolyte based on flame retardant can be further developed and applied to the design of other non flammable battery systems.