Professor Atsuo Yamada and his team recently developed a self healing battery material which could significantly extend the life of sodium ion batteries and give them higher capacities as well.
As batteries charge and discharge, the metallic layers inside degrade and develop cracks or flakes - called stacking faults - which reduce the batteries' ability to store and deliver charge. These stacking faults occur because the material is held together by weak Van der Waals forces, which is easily overwhelmed by the stress put on the materials during charging and use.
Yamada and colleagues demonstrated that a sodium battery is made with oxygen redox-layered oxide (Na2RuO3) can self-heal. Not only does the degradation from charge and discharge cycles diminish, but the layers actually self-repair. This is because the material the researchers demonstrated is held fast by coulombic attraction, which is far stronger than the Van der Waals force.
"This means batteries could have far longer life spans, but also they could be pushed beyond levels that currently damage them," said Yamada. "Increasing the energy density of batteries is of paramount importance to realize electrified transportation."