To solve the problem of low charging efficiency and high self-discharge of Fe-Ni batteries, the structure and electrochemical performance of Fe3O4 anodes surface-modified by 0~1wt% Li2O-2B2O3 (LBO) were studied. The results show that the appropriate amount of LBO (0.1 wt%) can be deposited on the surface of electrode uniformly, and there is no obvious chemical reaction between LBO and Fe3O4. The Fe3O4 electrode modified by 0.1wt% LBO has an electrochemical capacity up to 315.2 mAh/g, 54.1 mAh/g higher than Fe3O4 electrode without LBO, and its charging efficiency, cycle performance and self-discharge are improved. This improvement is directly related to the reduction of charge transfer impedance, as well as the increase of hydrogen evolution overpotential and corrosion resistance.