Aqueous magnesium battery electrolyte

Abstract

The invention discloses an aqueous magnesium battery electrolyte. The aqueous magnesium battery electrolyte comprises one or more organic anion salts, the organic anion salt comprises carboxylate, alkyl sulfate and alkyl sulfonate; the organic anion salt is short carbon chain salt and long carbon chain salt; the number of carbon atoms of the short carbon chain salt is 1-4, and the number of carbon atoms of the long carbon chain salt is 4-18; according to the invention, the micromolecular organic anion salt is used as the supporting electrolyte of the aqueous magnesium battery for the first time, so that the damage of anions in the conventional electrolyte to a passive film is completely eliminated. By optimizing the length of the carbon chain and the type of functional groups, the problem of hydrogen evolution corrosion in the discharge process can be effectively avoided on the premise of meeting normal discharge of the magnesium negative electrode, and the utilization rate of the magnesium negative electrode is improved.

Description

Technical field [0001] The present invention belongs to the field of magnesium batteries, specifically relates to the application of an electrolyte in an aqueous magnesium battery. Background [0002] Magnesium metal is an ideal chemical power negative electrode material with an electrode potential negative (Mg+2OH - →Mg(OH) 2 +2e，E＝-2.69V vs. SHE), high specific capacity (mass specific capacity 2.2Ah / g, volume specific capacity 3.8Ah / cm 3 ), the abundance of reserves in the earth's crust (2.33wt.%), low cost and environmental friendliness, etc., are used in Mg / MnO2, Mg / CuCl, Mg / AgCl, magnesium / air, magnesium / dissolved oxygen batteries. However, the magnesium anode exhibits serious anodized hydrogen evolution corrosion problems in conventional NaCl and MgClO4 electrolytes, making its actual discharge performance much lower than the theoretical value, and at a small current density (≤ 10mA / cm 2 ), the current efficiency is usually less than 65%, considering the unevenness of the e...

AI Technical Summary

Problems solved by technology

However, the problems of the above measures are: 1) the effect of the alloying elements has no additive effect; 2) the corrosion inhibitor cannot eliminate the Cl - The damage to the passivation film and the problem of hydrogen evolution at the anode still exist

[0004] There is still no good solution to the anode hydrogen evolution problem of magnesium anode