▎ 摘　　要

NOVELTY - Metal ion transport material, which is nano fiber. The surface interface of the nano fiber has a polar functional group coordinated with the metal ion. The polar functional group comprises a cyano group, and at least one of a sulfonic group, a hydroxy group, a carboxy group, an amino group and a carbonyl group. USE - The material is useful in battery diaphragm (claimed). ADVANTAGE - The material: has high electrochemical performance and safety performance, and improves migration number of zinc ion and ion conductivity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: a battery separator; preparing battery diaphragm; and a metal ion battery using the metal ion transport material or the battery separator.