The storage battery as an auxiliary device for renewable energy generation invites wide attention. The lithium-ion battery that is predominantly popular in the market needs lithium, and Japan heavily depends on imports for the supply of lithium. Sodium exists abundantly in the sea, and it can set Japan free from importing lithium. Two researchers of Tokyo Scientific University developed a new electrode material that is an oxide and able to store electricity using sodium ion instead of lithium ion in alliance with GS Yuasa.
The oxide they developed has a lamella structure and contains nearly the same amount each of iron and manganese. And the lamellarly-structured oxide stores electricity between layers. The research team confirmed that it is the same as the electrode material of a lithium-ion battery in terms of the capacity to store electricity and the speed of charging and discharging. At this stage, they evaluated the oxide as an electrode material. They plan to build a battery that uses the new material as the positive electrode and a carbon material as the negative electrode, and wish to put the new battery into practical use in five years. Their paper was published in the British science magazine “Nature Materials” (Electronic version) in April 30.