An Australian-Japanese team tested a new electrode material with "unprecedented stability" in a solid-state battery
One problem, even with modern batteries, is their loss of performance and capacity over time as a result of chemical wear. Despite many advances, this is also the reason why, for example, the runtime of smartphones decreases noticeably after just two to three years of frequent use.
Of course, these are not the only devices affected. Over time, this wear and tear is also noticeable in electric cars. A new discovery by researchers at the University of New South Wales in Australia and Japan's Yokohama National University now gives reason to hope that this problem will be solved in the future.
Test run for vanadium
They have been testing lithiated vanadium oxides with a disordered salt lattice structure as an option for the positive electrodes (cathodes). In combination with an optimized electrolyte, they achieved not only high energy densities of up to 750 watt-hours per kilogram (conventional lithium-ion batteries in e-cars currently achieve around 120 Wh/kg), but also considerable resistance to wear.
An experimental solid-state battery with sulfite-based electrolyte delivered a charge density of 300 mAh/g. It continued to maintain this after 400 charge and discharge cycles. The low shrinkage and expansion of the cathode is also important here. Due to its chemical properties, its volume remains approximately the same in both fully charged and discharged states. By further optimizing the electrolyte, the team believes that a "dimensionally invariant" material could be developed.
"The lack of capacity loss after 400 charge cycles is indicative of the superior performance of this material compared to conventional solid-state cells with layered structures," says Neeraj Sharma, who co-authored the paper on the work with Takuhiro Miyuki. "This discovery could dramatically reduce battery costs. The development of practical, high-performance solid-state batteries could also lead to the development of advanced electric vehicles."
This invention may also prove important for another hurdle that e-cars still face, says research leader Naoaki Yabuuchi. Further improvements in such dimensionally stable materials offer potential for much faster charging. Assuming charging stations with the appropriate power, he says it's quite conceivable that new generations of e-cars could be charged in five minutes.
To further expand the development of e-cars, it will require the promotion of alternative means at every level. global society can come together in a network and unite knowledge, influence, creativity and willpower around the world to achieve the SDGs (Sustainable Development Goals) together.
More information: https://www.nature.com/articles/s41563-022-01421-z