Processing methods and procedures of lithium battery pack aluminum shell processing

abstract

Processing methods and processes of lithium battery pack aluminum shells. Lithium battery packs generally use aluminum shells to increase the stability of the battery. Lithium battery packs have the advantages of high precision and anti-shake, which solves the problem of deviation in most lithium battery aluminum shell processing equipment. To reduce the weight of the battery, it is an inevitable choice to use aluminum alloy materials to make lithium battery shells. This article will talk about the processing methods of lithium battery pack aluminum shells.

What is a lithium battery aluminum shell?

A lithium battery aluminum shell is a battery shell made of aluminum alloy material, mainly used in square lithium batteries. The reason why lithium batteries are packaged in aluminum shells is that they are light and safer than steel shells. There are two types of lithium battery pack aluminum shell designs: square corners and rounded corners. The material of the aluminum shell is generally aluminum-manganese alloy. The main alloy components it contains are Mn, Cu, Mg, Si, Fe, etc. These five alloys play different roles in lithium battery aluminum shells. For example, Cu and Mg improve strength and hardness, Mn improves corrosion resistance, Si can enhance the heat treatment effect of magnesium-containing aluminum alloys, and Fe can improve high-temperature strength.

Because of the above relative advantages of aluminum shells for lithium battery packs, aluminum shell lithium batteries are currently the mainstream of liquid lithium batteries and are used in almost all fields related to lithium batteries. Aluminum shells for lithium batteries are presently evolving towards high hardness and lightweight technology, which will provide the market with lithium battery products with superior technology.

The processing method of the aluminum shell for lithium battery pack

Given the shortcomings of the existing technology, the utility model provides a fully automatic lithium battery aluminum shell processing equipment. Lithium battery packs generally use aluminum shells to increase the stability of the battery. In most of the existing lithium battery aluminum shell processing equipment, when processing the aluminum shell, the upper cover, and the shell are connected to produce shaking, causing the upper cover to deviate from the original position. Then the aluminum shell has deviations, the processing accuracy is affected, and the use and appearance of the aluminum shell are affected.

In terms of technical maturity, aluminum shell technology is very mature, and the requirements for material technology (such as inflation rate, expansion rate, and other indicators) are not high, there are no technical barriers in the industry; while soft-pack lithium-ion batteries currently have many technical problems to be solved, especially in the battery cycle expansion index, most battery factories have not yet solved this problem. The degree of automation in the manufacturing of aluminum shell batteries is higher than that of soft-pack lithium-ion batteries. Therefore, to a certain extent, the impact of human factors on product consistency is reduced, while saving labor costs.

Lithium battery production process

Objectively speaking, the production process of lithium battery packs is divided into three major sections: pole piece production, battery cell production, and battery assembly. In the lithium battery production process, pole piece production is the foundation, battery cell production is the core, and battery assembly is related to the quality of lithium battery products. The specific links of the lithium battery production process include positive electrode slurry drawing, negative electrode slurry drawing, positive electrode sheet, negative electrode sheet, steel shell assembly, liquid injection and testing, and packaging.

What types of surface treatment processes are there for power battery aluminum shells?

1. Powder electrostatic spraying process:

The working principle of the powder electrostatic spraying process is almost the same as that of the general liquid coating electrostatic spraying method, the difference is that powder spraying is dispersed, not atomized. It is a coating sprayed by an electrostatic powder spray gun, which makes the powder particles negatively charged while dispersing. The charged powder particles are coated on the grounded power battery aluminum shell under the action of airflow and electrostatic attraction, and then heated, melted, and solidified into a film.

2. Electrophoretic painting process:

The electrophoretic painting process is a coating method that uses an external electric field to make the pigments and resin particles suspended in the electrophoretic liquid migrate in a directional manner and deposit on the surface of the substrate of one of the electrodes. It has the characteristics of water solubility, non-toxicity, and easy automation control. After the electrophoretic painting process, the surface of the power battery aluminum shell has a soft gloss and can resist the invasion of cement and mortar acid rain.

3. Electrochemical surface ceramic process:

The aluminum shell of the power lithium battery pack adopts plasma plasma-enhanced electrochemical surface ceramic process. Although the quality is excellent, the cost is relatively high. The profiles produced by this process have more than 20 tones. Its biggest feature is that they can be colored like printed cloth as needed. The surface of the profile is colorful and has an excellent decorative effect.

4. Frosted process:

Frosted aluminum profiles avoid the disadvantage that bright aluminum alloy profiles will cause light interference under certain environments and conditions in architectural decoration. Its surface is as delicate and soft as brocade, which is very popular in the market. However, the existing frosted materials must overcome the uneven surface sand particles and the shortcomings of visible mold patterns.

summary

The production process of lithium battery packs is quite complicated. After all, the safety performance of lithium-ion battery products is directly related to the life and health of consumers. The production and manufacturing of lithium batteries have high requirements for the performance, precision, stability, and automation level of equipment. Therefore, every link in the production process of lithium battery pack aluminum shells must be strictly and carefully managed to improve the safety performance of lithium battery products.