Formation method of nickel-metal hydride battery

Abstract

The invention provides a formation method of a nickel-metal hydride battery. The method comprises the steps that after a battery subjected to liquid injection is enabled to stand for a period of time,the battery is pre-charged for 1 hour at the current of 0.1 C, the pre-charged battery is placed in the environment at the temperature of 40 DEG C for 24 hours, then the battery is formed, wherein the formation indicates that 0.15 C current is used for conducting multiple times of charging and discharging, the charging voltage is limited to be 1.55 V, and the discharging cut-off voltage is 1V. The method can effectively improve the utilization rate of the positive and negative active substances of the nickel-metal hydride battery and improve the charge retention capability of the battery.

Description

technical field [0001] The invention relates to the technical field of nickel-hydrogen batteries, in particular to a method for forming nickel-hydrogen batteries. Background technique [0002] Ni-MH battery formation is a process in which the battery reaches the rated discharge capacity through a certain method of charging and discharging cycles before use. The purpose of chemical formation is to make the performance of the hydrogen storage alloy, the negative electrode active material, reach an ideal use state. [0003] The hydrogen storage principle of the hydrogen storage alloy is that under the action of a certain temperature, pressure and electrode potential, the hydrogen storage alloy reacts reversibly with hydrogen ions; firstly, a solid solution α-MH is formed X , hydrogen reacts with the hydrogen storage alloy through the hydride layer, α-MH X React with hydrogen, produce phase transition, and generate solid solution β-MH X , thus completing the hydrogen storage ...

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.

Images