The electrochemical properties of La0.9Sm0.1Ni(5.0−x)Co x (x=2.0, 2.5, 3.0) hydride electrode alloys with and without magnetization treatment, including the electrochemical capacity C max, the charge–discharge life cycle and the high-rate dischargeability (HRD), are investigated in detail. The results show that, the effect of magnetization treatment on the electrochemical properties of the alloys studied is marked, and this effect varies with the alloy composition. After being magnetized, the electrochemical capacity of the alloys increases, the capacity decay rate decreases and the HRD improves. According to the linear polarization and anodic polarization measurements, the exchange current density I 0 and the limiting current density I L of the alloys before and after being magnetized are both found increased.