Aluminum plastic membrane detection method

Abstract

The invention relates to an aluminum plastic membrane detection method. The aluminum plastic membrane comprises an aluminum layer, an insulating plastic layer packing the aluminum layer, and a cavity for accommodating a battery cell. The aluminum plastic membrane detection method comprises the following steps: taking a to-be-detect aluminum plastic membrane, injecting a copper sulfate solution into the concave cavity of the to-be-detect aluminum plastic membrane, mounting an anode lug and a cathode lug for the to-be-detect aluminum plastic membrane to enable the anode lug and the cathode lug to be communicated with the copper sulfate solution, packaging the concave cavity, filled with the copper sulfate solution, of the to-be-detect aluminum plastic membrane to fix the anode lug and the cathode lug and enable the anode lug and the cathode lug to protrude out of the aluminum plastic membrane, connecting the anode lug with the anode of a power source, connecting the cathode lug with the cathode of the power source, electrifying for scheduled time, opening the to-be-detect aluminum plastic membrane, judging whether a red part exists, and if a red part exists , the red part of the to-be-detect aluminum plastic membrane is defective. According to the invention, the anode lug and the cathode lug are mounted on the aluminum plastic membrane, are communicated with the copper sulfate solution and connected onto the power source, and are electrified to detect whether the red part exists in the aluminum plastic membrane, so that whether the aluminum plastic membrane is qualified can be judged, therefore, the operation is simple and convenient, and even for a tiny defect, the defective position can be accurately detected.

Description

technical field [0001] The invention relates to the technical field of battery detection, in particular to an aluminum-plastic film detection method. Background technique [0002] With the continuous development of electronic products, lithium-ion batteries have been widely used, and the current electronic products are constantly being updated, and the requirements for lithium-ion battery products are getting higher and higher, especially in terms of safety and reliability. [0003] In order to eliminate the potential safety hazards of lithium-ion batteries, it is usually necessary to carry out various inspections on the batteries, among which the detection of defects such as damage to the aluminum-plastic film is a mandatory inspection item for batteries leaving the factory. Aluminum-plastic film is usually composed of three layers: the outermost nylon layer, the middle layer of aluminum foil, and the innermost CPP layer. Their total thickness is in the range of 80um~150um....

AI Technical Summary

Problems solved by technology

[0004] The aluminum-plastic film usually has a cavity to accommodate the battery. For example, the cavity is formed by punching the shell. The aluminum-plastic film itself will stretch during stamping, and the inner layer will also have a weak zone as it is stretched, because there are two sides of the inner layer. With the existence of potential difference, the weak area in the inner layer is easily penetrated by lithium ions. With the penetration of lithium ions, the electrolyte with higher conductivity will also penetrate the inner layer and contact the aluminum layer in the middle of the aluminum-plastic film. The electrochemical reaction with the electrolyte causes the aluminum layer to be corroded and consumed continuously and produces gas. The increase in the internal pressure of the battery will cause the battery to swell, bringing unsafe factors to the battery

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