Regulation of the Anode Electrodeposition Behavior of Aqueous ZincIon Batteries by an <scp>l</scp><i>-</i>Alanine<i>-</i>Modified Glass Fiber Separator

Aqueous zinc ion batteries (AZIBs) are an important research direction in the current energy storage field. However, dendrites and hydrogen evolution limit their wide application. Here, we performed heat treatment modification of glass fiber (GF) using l-alanine and sodium hydroxide solution. The −NH2 and −COOH functional groups contained in l-alanine introduced into LA@GF synergistically promoted the uniform deposition of zinc ions. The −NH2 effectively acts as an ion pump for zinc ion transport and improves the transport kinetics of zinc ions. After the modification, the mobility number of zinc ions and the exchange current density are significantly increased. Meanwhile, the −COOH functional group can form a hydrogen bond with water molecules, thus facilitating the desolvation process of zinc hexahydrate ions. The symmetric batteries using the LA@GF separator have a cycle life of more than 600 h at 0.5 mAh cm–2.