In order to improve the serious polarization problem of zinc negative electrode in zinc-nickel secondary batteries and to improve the electrochemical performance and cycling stability of zinc negative electrode, a hydrothermal-coprecipitation method was used to prepare CaSn(OH)6 deposited on the surface of calcium zincate and used as a negative active substance of zinc-nickel batteries. The results show that the hydrothermal-coprecipitation method can be used to deposit CaSn(OH)6 on the surface of calcium zincate, and the prepared calcium zincate has a high crystallinity. Based on the cyclic voltammetry test, the addition of CaSn(OH)6 reduces the charge transfer resistance of calcium zincate and is beneficial to accelerating the electrochemical reaction rate of calcium zincate in alkaline electrolyte, thus improving the discharge rate in the reaction process. The results of electrochemical impedance spectroscopy confirm that calcium zincate with CaSn(OH)6 deposited on the surface electrode charge transfers impedance less rather than that of pure calcium zincate. The capacity retention rate of the battery is 85.34% after 70 charge discharge cycles at 0.2 C when calcium zincate with CaSn(OH)6 deposited on the surface is used as a negative active material of Zn-Ni battery.