The magnesium secondary battery is not a concept that has emerged only recently. From the Israeli scientist Doron Aurbach (Doron Aurbach) in 2000 first proposed the magnesium secondary battery model, the electrochemical system has been developed for more than 20 years. Qingdao Energy Institute Solid State Energy Systems Technology Center researcher Cui Guanglei explained that the magnesium metal secondary battery is a recyclable battery with magnesium metal as the negative electrode, the core of the composition of the magnesium metal secondary battery is the magnesium negative electrode, electrolyte and can be embedded in the magnesium cathode material.

According to reports, magnesium metal has a very high volume capacity, is an excellent choice as a high volume energy density battery negative electrode. Magnesium metal secondary battery works with lithium secondary battery principle, but compared with lithium secondary battery is safer, the reason is that magnesium and most magnesium compounds are non-toxic or low toxicity, and magnesium is not as active as lithium, easy to process operation, but also safer than lithium; magnesium battery is not similar to lithium battery dendrite growth problem; in terms of price, due to the higher abundance of magnesium in the earth's crust, so its price is cheaper than lithium.

With the implementation of "double carbon" strategy, new energy ushers in leapfrog development. As one of the key equipment widely used in the field of new energy, the importance of secondary batteries has been paid attention to by all parties.

Cui Guanglei said, although researchers in magnesium storage cathode, magnesium electrolyte, magnesium metal anode and other key materials have made important progress, but the magnesium metal secondary battery there are still many basic scientific problems to be overcome, the industrial application is still in the early stage of exploration.

Specifically, the development of magnesium metal secondary battery is facing two major bottlenecks. Cui Guanglei said, one is the magnesium electrolyte as the "blood" in the battery system, plays an important role in the transfer of magnesium ions between the positive and negative electrodes, it is in direct contact with the positive and negative electrode materials inside the battery system, so it needs to take into account the special needs of magnesium metal anode and high energy storage magnesium anode, which greatly limits the choice of magnesium electrolyte components This greatly limits the choice of magnesium electrolyte components, the development of a new magnesium electrolyte system with good compatibility with the cathode interface is of great significance; Secondly, because the divalent magnesium ion not only has two charges, and "small", which is both magnesium ion can store more charge in the same volume conditions of the mystery, but also caused the magnesium ion has a large charge density, strong polarization The strong polarization will lead to the magnesium ion in the cathode material lattice inside the larger coulombic force of the role of the hold, resulting in the slow diffusion of magnesium ions, so the common magnesium metal secondary battery embedded cathode material structure generally shows poor reversible deembedding magnesium ion ability, the development of new efficient magnesium storage cathode material is urgent.

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