A kind of formation method of nickel-metal hydride battery

Abstract

The invention provides a method for forming a nickel-metal hydride battery. After the battery that has been filled with liquid is left for a period of time, it is precharged with a current of 0.1C for 1 hour, and the battery that has been precharged is placed in an environment of 40 ° C. After 24 hours, the battery was formed. The said formation is a process of charging and discharging multiple times with a current of 0.15C, wherein the charging voltage is limited to 1.55V, and the discharge cut-off voltage is 1V. The method can effectively improve the utilization rate of the positive and negative active materials of the nickel-metal hydride battery, and improve the charge retention capacity of the battery.

Description

Technical field [0001] The present invention relates to the technical field of nickel-metal hydride batteries, in particular to a nickel-metal hydride battery formation method. Background [0002] Nickel-metal hydride battery formation is the process of the battery to achieve the rated discharge capacity by performing multiple charge and discharge cycles by a certain method before use. The purpose of chemical formation is to achieve the performance of the hydrogen storage alloy of the negative active substance to achieve the ideal state of use. [0003] The hydrogen storage principle of hydrogen storage alloy is that under the action of certain temperature, pressure and electrode potential, hydrogen storage alloy can react reversibly with hydrogen ions; first, the solid solution α-MH is generated X Hydrogen reacts with hydrogen storage alloys through a hydride layer α-MH X Reacts with hydrogen to produce a phase transition that generates a solid solution β-MH X , which completes...

AI Technical Summary

Problems solved by technology

The disadvantage of this method is that, as the method described in its embodiment, the time spent has reached about 200 hours, wherein the normal temperature shelving and high temperature shelving time is about 168 hours; long-term shelving and formation will have the following problems; the first, work efficiency Low; second, long-term storage, especially long-term high-temperature storage, the CoO in the positive electrode cannot be converted into CoOOH in time. In this process, it is easy to react to form other forms of Co compounds, which will increase the internal resistance of the battery and deteriorate battery performance.

However, while the two methods control the positive electrode reaction, they do not consider the influence of other parts on the performance of the battery as a whole; in particular, they ignore the influence of the diffusion uniformity of the electrolyte on the performance of materials such as separators, spherical nickel, and hydrogen storage alloys.

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