University of Tsukuba develops magnesium solid-state battery
According to PC Watch on February 20: Japan's University of Tsukuba announced that by using low-cost magnesium metal as the anode, porous graphene as the cathode, and solidifying the electrolyte to prevent leakage, a fully solid-state magnesium rechargeable battery has been developed.
Magnesium rechargeable batteries work by taking oxygen from the atmosphere, with carbon materials as the cathode, magnesium as the anode, and magnesium chloride as the electrolyte. They can be constructed into low-cost, high-capacity rechargeable batteries. Their theoretical performance is considered similar to lithium rechargeable batteries. However, due to the presence of chloride ions, internal chlorination occurs, leading to a decrease in performance, which remains a challenge to be solved.
In this study, the University of Tsukuba developed a porous graphene, which was chemically doped with nitrogen as a cathode with strong resistance to chlorine. Specifically, graphene was produced on a porous metal surface through a chemical vapor deposition (CVD) method, then the porous metal serving as the mother body was dissolved with acid, forming a nitrogen-doped and structurally porous graphene.
On the other hand, commercial polymer gels were used, with the anode impregnated with commercially available magnesium, and the electrolyte used magnesium chloride. When evaluating the performance of this fully solid-state magnesium air rechargeable battery, its performance was better than that of batteries with platinum-based electrodes as the cathode.
When studying the discharge mechanism with a transmission electron microscope, it was found that during the half-discharge process, a film-like discharge material was confirmed on the graphene membrane. When fully discharged, the discharge material blocked the inner structure of the tube, and the tube diameter also expanded, thereby generating a larger capacity.
On the other hand, after being fully charged, it was confirmed that it returned to the initial graphene state without any discharge material, and it was not prone to degradation, with a long lifespan.
Additionally, no leakage was observed during the battery bending test, and regardless of the bending angle or the recovery of the bend, the charging and discharging performance remained almost unchanged.
The results of this study show that the possibility of using rare earth elements and precious metals in rechargeable batteries can be reduced.
Original article: toutiao.com/article/1857707099942025/
Statement: This article represents the views of the author.