Decrease in dendritic growth and overpotential through in‐situ generated lithium‐aluminum alloys for lithium metal batteries

Although the need for the development of lithium metal batteries to further enhance the energy density of conventional lithium-ion batteries is increasing, the large overpotential and dendritic growth during lithium-ion deposition and dissolution impedes their commercialization. In this study, we propose a method of adding aluminum sheets on the surface of the lithium metal negative electrode that can improve performance without significantly changing the present battery fabrication processes. In this method, the surface of the negative electrode is changed to a lithium-aluminum alloy after the injection of electrolyte through a self-discharge reaction. The treated surface helps reduce overpotential and dendritic growth by creating a uniform current distribution and lowering the activation energy of lithium-ion deposition and dissolution. Owing to these advantages, full-cells manufactured with lithium titanium oxide also exhibit low resistance and good cycle performance at a fast C-rate.