Battery core packaging film and battery

Abstract

The invention discloses a battery core packaging film and a battery. Wherein, the battery core packaging film includes an isolation layer, an aluminum foil layer and a sealing layer arranged in sequence, and a protective layer is arranged between the aluminum foil layer and the sealing layer, wherein the protective layer is a plastic layer. Through the above method, the present invention can prevent the corrosive liquid of the battery from infiltrating through the sealant layer to corrode the surface of the aluminum foil layer, ensure that the sealant layer on the surface of the aluminum foil layer does not fall off, the battery does not leak, and improve the service life of the packaging film; The deterioration of the electrolyte caused by the infiltration and corrosion of each layer of the packaging film ensures the performance of the battery; prevents the micro-delamination and micropore penetration of the heat-sealed battery electrodes caused by the instantaneous high-current discharge of the battery.

Description

Technical field [0001] The invention relates to the field of batteries, in particular to a battery core packaging film and a battery. Background technique [0002] Aiming at the problem that lithium batteries packed in metal boxes are easy to release gas during use, and the pressure increase causes explosion problems, a new type of flexible packaging material, namely aluminum-plastic film, has been introduced on the market. This packaging material can expand to release pressure and prevent explosion. [0003] Such as figure 1 As shown, in the prior art, the flexible packaging material usually includes an isolation layer 1, an aluminum foil layer 2, and a sealing glue layer 3. In the production process of the battery, the cell is packaged with packaging film, and two metal pole pieces are drawn out through heat sealing as the positive and negative electrodes of the battery. However, such flexible packaging materials have the following disadvantages: ①The corrosive liquid of lithiu...

AI Technical Summary

Problems solved by technology

However, such flexible packaging materials have the following disadvantages: ①The corrosive liquid of the lithium battery can usually infiltrate through the sealing layer 3 and directly corrode the surface of the aluminum foil layer, thereby causing the sealing layer attached to the surface of the aluminum foil layer to fall off, and the packaging film becomes invalid. thus the battery fails

②The sealant layer is generally polypropylene, and the polypropylene is drooled to the surface of the aluminum foil to form a film by coating method. The sealing layer is in contact with the adhesive layer, which will cause electrolyte pollution and cause battery performance degradation

③For high-power discharges that may occur many times during actual use, because the current causes the battery electrodes to heat up, and the battery electrodes are connected to the heat-sealing layer, thermal deformation and heat transfer make the gap between the heat-sealing layer and the aluminum foil layer near the electrodes Produce microporosity and microdelamination, reduce or even destroy the performance of the battery

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