Nickel-metal hydride battery sample preparation method for synchrotron radiation XRD in-situ test technology

Abstract

The invention discloses a nickel-metal hydride battery sample preparation method for a synchrotron radiation XRD in-situ test technology, and relates to the technical field of nickel-metal hydride batteries. A hydrogen storage alloy negative electrode prepared by a slurry coating method is placed in a negative electrode cabin of a battery cabin, meanwhile, a nickel hydroxide positive electrode anda nickel hydroxide negative electrode are placed in a positive electrode cabin side by side in the same vertical plane, and then a 6M potassium hydroxide electrolyte is injected to submerge the electrodes. The thickness of the front wall and the rear wall of the negative electrode cabin and the distance between the front wall and the rear wall of the negative electrode cabin do not exceed 1 mm, the front wall and the rear wall are each provided with a window used for allowing X-rays to penetrate through, and the windows are covered with quartz plates with the thickness not exceeding 0.2 mm. According to the invention, X-rays can smoothly penetrate through a sample to be tested. In addition, the battery cabin is provided with the base and is used for installing the battery cabin on an experiment table of synchrotron radiation XRD equipment, and meanwhile, the test equipment can be effectively prevented from being damaged by alkaline electrolyte leakage.

Description

technical field [0001] The invention relates to the technical field of nickel-metal hydride batteries, in particular to a method for preparing nickel-hydrogen battery samples used in synchrotron radiation XRD in-situ testing technology. Background technique [0002] The nickel-metal hydride battery uses hydrogen storage alloy as the negative electrode material, nickel hydroxide as the positive electrode material, and an alkaline aqueous solution based on potassium hydroxide as the electrolyte. Hydrogen atoms produced by hydrolysis diffuse into the body of the hydrogen storage alloy during charging to form metal hydrides to store hydrogen atoms in the negative electrode; during discharge, the metal hydrides release hydrogen atoms, which are oxidized into water molecules on the surface of the alloy and incorporated into the electrolyte . Studies have shown that the performance of negative electrode materials dominates the electrochemical performance of Ni / MH batteries. Theref...

AI Technical Summary

Problems solved by technology

However, in the general sample preparation method for testing the electrochemical performance of batteries, the volume of the battery compartment used is relatively large, the distance between the front and rear bulkheads is long, and the bulkheads are generally made of thicker glass or plastic materials, coupled with high-concentration electrolyte , X-rays are basically impenetrable, and cannot be placed on the sample stage of the synchrotron radiation XRD instrument; moreover, in order to save space, the positive and negative electrodes are often wound into a sandwich, and the negative electrode is sandwiched between the two positive electrodes. They are separated by a nylon diaphragm. Such a battery assembly seriously blocks the passage of X-rays. Even if there is residual X-rays that can pass through, it must first pass through the positive electrode sheet and the diaphragm before reaching the negative electrode material. The resulting XRD pattern It will also be very messy due to the interference of various substances and cannot be analyzed

Therefore, no matter from the perspective of the battery compartment or the perspective of electrode assembly, the above sample preparation methods cannot be used for in-situ synchrotron radiation XRD testing

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