EVE Energy's automatic processing and assembly technology for lithium battery separators greatly improves operating efficiency

On August 2, EVE Energy announced that it plans to cooperate with Yunnan Enjie New Materials Co., Ltd. (hereinafter referred to as "Enjie Co., Ltd.") to establish a joint venture in Jingmen. The joint venture will focus on the manufacture of lithium-ion battery separators and coating films, with an annual production capacity of 1.6 billion square meters of wet-process base films and coating films that fully match the production capacity.

According to relevant data, lithium batteries are a new generation of chemical power sources that emerged in the 1990s. In terms of lithium battery packaging structure, they generally include lithium-ion steel-shell packaged batteries and polymer soft-packaged batteries. Battery separators are used to separate the positive and negative electrodes of the battery and are necessary materials for manufacturing battery cells. Commonly used battery separators generally include cylindrical side membranes and disc-shaped bottom membranes.

In the existing manufacturing technology, the processing and assembly of the bottom film and the side film in the battery processing process are basically done manually: the staff first cuts the bottom film and the side film into shape manually, and then manually puts the formed bottom film and the side film into the battery shell. This manual solution generally requires at least three operators to complete the processing and assembly of the bottom film and the side film, so the production efficiency is low, the processing error is large, and the waste of raw materials is serious.

In order to improve the existing production methods, Yiwei Lithium Energy applied for an invention patent named "Automatic processing and assembly equipment for battery diaphragms" (application number: 201010205714.8) as early as June 13, 2010. The applicant was Huizhou Yiwei Lithium Energy Co., Ltd.

Based on the relevant information currently disclosed in this patent, let us take a look at this battery diaphragm automatic processing and assembly equipment solution.

As shown in the above figure, it is a structural block diagram of the battery diaphragm automatic processing and assembly equipment invented in this patent. The battery diaphragm automatic processing and assembly equipment 100 mainly includes a workbench 10, a bottom film feeding mechanism 20, a bottom film processing mechanism 30, a side film feeding mechanism 40, a side film processing mechanism 50, an electrical control box 60 and a control panel 70.

This battery separator equipment can automatically process the bottom film and the side film, and assemble the formed bottom film and the side film simultaneously on the workbench in the battery shell located at the first predetermined position. It is more suitable for hard-packaged carbon-packaged lithium batteries, especially carbon-packaged lithium batteries with a cylindrical shape.

When processing and assembling the battery separator, the bottom film feeding mechanism is provided with the bottom film wound into a disc shape, and the bottom film is transmitted to the bottom film processing mechanism. The bottom film processing mechanism processes the bottom film into a predetermined shape and size, and transmits the formed bottom film to a second predetermined position of the workbench.

The user inputs and executes through the control panel, and the system, under the control of the electrical control box, obtains the formed side film from the side film processing mechanism on the workbench, winds the formed side film into a basically cylindrical shape, and then assembles the cylindrical side film and the formed bottom film located at the second predetermined position in the battery casing at the same time.

As shown in the figure above, it is a schematic diagram of the structure of the bottom film feeding mechanism in the above system, which mainly includes a first rotating shaft 22 rotatably connected to a bracket 21, a bottom film material tray 23 fixed on the first rotating shaft, a first transmission part 25 fixed on a support 24, and a first driving part 26. The bottom film wound into a disc is loaded in the bottom film material tray, and under the action of the first transmission part, the bottom film is taken from the bottom film material tray and transmitted to the bottom film processing mechanism.

Finally, it is a structural schematic diagram of the edge film feeding mechanism and the edge film processing mechanism. It can be seen that the structure of the edge film feeding mechanism 40 is similar to that of the bottom film feeding mechanism, and mainly includes a fifth rotating shaft 42 rotatably connected to the bracket 41, a edge film material tray 43 fixed to the fifth rotating shaft, a second transmission part 45 fixed to the support 44, and a third driving part 46.

In addition, the edge film feeding mechanism also includes a sensor 47, which is arranged between the edge film material tray and the second transmission part, and is used to detect whether there is edge film passing. When there is waste material in the processed edge film, the edge film feeding mechanism is also provided with a driving part and a rotating shaft, which are used to roll up the processed edge film waste material or transfer it to a waste material box, so as to drive the fifth rotating shaft to rotate and release the edge film, reduce the burden of the third driving part, and thus improve the accuracy of edge film transmission.

The above is the automatic processing and assembly equipment for battery separators invented by EVE Energy. In this solution, the bottom film and side film are cut and assembled automatically, which greatly improves the operation efficiency. This helps enterprises improve production capacity, stabilize product quality, reduce product defective rate, and reduce undesirable phenomena such as waste of raw materials.