Disordered materials hold promise for better batteries
Lithium batteries, with their exceptional ability to store power per a given weight, have been a major focus of research to enable use in everything from portable electronics to electric cars. Now researchers at MIT and Brookhaven National Laboratory have found a whole new avenue for such research: the use of disordered materials, which had generally been considered unsuitable for batteries.In a rechargeable lithium-based battery, lithium ions — atoms that have given up an electron, and thus carry a net charge — are pulled out of the battery’s cathode during the charging process, and returned to the cathode as power is drained. But these repeated round-trips can cause the electrode material to shrink and expand, leading to cracks and degrading performance over time.In today’s lithium batteries, those cathodes are usually made of an orderly crystalline material, sometimes in a layered structure. When slight deviations from that perfect order are introduced,...