METHOD TO PROTECT A LITHIUM METAL ANODE IN A RECHARGEABLE LITHIUM METAL BATTERY

A rechargeable metal halide battery fabricated with a liquid nitrogen treated metallic anode demonstrates a stable cycle life with a slow rate of degradation and high discharge capacity in comparison to battery cells with untreated anodes. The anode, which may be an alkali metal and/or an alkaline earth metal, is pretreated with the liquid nitrogen prior to formation in a battery stack. The liquid nitrogen treatment forms a metal nitride on a surface of the anode that (i) increases the surface area of the anode, (ii) acts as a passivation layer that prevents detrimental SEI-forming side reactions that degrade anodes, and (iii) suppresses dendrite growth. Where the anode is lithium, the metal nitride is lithium nitride (LiN).