The lithium battery manufacturing process refers to the method and steps of making lithium ions and other raw materials into final usable lithium battery parts. Lithium batteries mainly include components such as positive electrodes, negative electrodes, and diaphragms. The preparation of positive and negative electrodes is an extremely complex part of the entire process, and the assembly of lithium batteries requires strict quality control to ensure safety and reliability. In this case, what is the lithium battery manufacturing process like?
In the entire process, the preparation process of each link is very important. For example, lithium nickel acid (ternary material) is superior to lithium cobalt acid in electrochemical performance and thermal stability, and the larger capacitance of lithium ions can increase the possibility of electric pulses and over-discharge. The process needs to implement scientific and standardized control to ensure that lithium batteries are fully considered in terms of performance and safety, and achieve the best working state.
What materials are needed in lithium battery production?
With the continuous development of science and technology, lithium batteries, as a new type of battery, have become a highly sought-after product in the market. As we all know, lithium batteries can be used in various devices such as mobile phones, laptops, electric vehicles, etc., and their advantages are lightness, high efficiency, and long life. However, have you ever thought about what materials are needed in the production process of lithium batteries? The following will reveal the production process of lithium batteries.
1. Positive and negative electrode materials
Positive and negative electrode materials are the most important and basic components of lithium batteries. It is characterized by strong electrochemical reactivity, large specific surface area, and sufficient energy storage space. Among them, the positive electrode material is mostly oxide or lithium iron phosphate, while the negative electrode usually uses graphite material.
Among the positive electrode materials of lithium batteries, the most commonly used are ternary materials (such as LiCoO2), and now also include more advanced quaternary materials (such as LiFePO4). Due to the large demand for positive electrode materials and their high market prices, dominating and controlling their prices is often the focus of competition among lithium battery manufacturers.
As for negative electrode materials, graphite is the best and cheapest choice. In addition, there are also new lithium batteries that use negative electrode materials such as silicon and its oxides, which have higher energy storage efficiency, but the cost is also higher.
2. Electrolyte
The electrolyte is an important medium that connects the positive and negative electrodes and transfers ions. It plays a variety of roles such as conducting electricity, diffusing ions, and ensuring battery activity. In lithium-ion batteries, in addition to having a certain ionic conductivity, the electrolyte must also meet the battery’s stable requirements for various environmental factors such as temperature and pressure. The electrolytes currently used on the market mainly include carbonates, carbonates, phosphates, and diformamides, among which carbonates occupy the vast majority of the market share.
In addition, special auxiliary agents such as humectants, vulcanizers, and plasticizers are also added to lithium battery electrolytes to improve the performance and life of the electrolyte.
3. Diaphragm
The diaphragm is a very important part of lithium-ion batteries. Its main function is to isolate the positive and negative electrodes, while promoting the reciprocating movement of lithium ions and maintaining the stability of the electrolyte system. The diaphragm needs to meet good conductivity and mechanical strength, and also needs corrosion resistance, high temperature resistance, flame retardancy and other characteristics. The most common material at present is polypropylene, in addition to polyurethane, polyester and other materials.
4. Shell material
The shell material is mainly used to protect the battery, and it is also the basis for the molding of lithium batteries. During the production process, metal, plastic and other materials are used to make the shell. Different types of batteries require different types of shell materials. For example, mobile phone batteries usually use aluminum alloy and iron alloy shells, while electric motorcycle batteries need to use stronger plastic materials such as ABS and polycarbonate.
5. Other auxiliary materials
In the production of lithium batteries, some auxiliary materials are also needed to ensure the quality and life of the battery. These materials include conductive glue, electrode belts, wiring pieces, sealing rings, leak-proof glue, etc. Although these accessories are not the main components of the battery, their lack will affect the quality and performance of the battery.
What are the steps in the production of lithium batteries?
With the development of science and technology, lithium batteries have become an indispensable part of modern electronic products. So, how are lithium batteries made? Below we will introduce the process steps of lithium battery production in detail.
1. Preparation of electrode materials
The positive and negative electrodes of the battery are both composed of electrode materials. Here we take lithium-ion batteries as an example, usually using lithium cobalt acid and graphite as electrode materials.
First, lithium cobalt acid and graphite are made into corresponding sheet electrode materials through multiple processes such as cutting, mixing, kneading, and cutting. The preparation of electrode materials will directly affect the performance and life of the battery, so it is necessary to maintain stable temperature and humidity during the preparation process to ensure that high-quality electrode materials can be obtained in the end.
2. Prepare the battery shell
The battery has a shell, which is generally made of metal aluminum. The battery shell plays a role in protecting the internal components of the battery.
When preparing the battery shell, the aluminum plate needs to be cut, expanded, spliced, and other processes. Because the shell needs to have a high degree of sealing and corrosion resistance, it is necessary to pay attention to process details during the preparation process to ensure the quality of the battery shell.
3. Assemble electrodes
The electrode is the core part of the battery. When assembling the electrode, the positive and negative electrode materials need to be stacked on the conductive copper foil respectively, and compressed and fixed through multiple processes, and then connected by ultrasonic welding.
During the assembly process, it is necessary not only to control the number of layers and arrangement of the electrode materials, but also to ensure that the contact state between the various parts of the electrode is stable to avoid internal short circuits in the battery and damage to the battery.
4. Inject electrolyte
The electrolyte also needs to be injected into the lithium battery to achieve ion transfer between the positive and negative electrodes, so as to complete the electrochemical reaction of the battery and generate electricity.
Generally, lithium batteries use organic solvents containing lithium salts as electrolytes. The solvent can continuously diffuse back and forth with the lithium ions in the positive electrode material to achieve reactions between the electrodes. Although this electrolyte has high conductivity and stable performance, it is also corrosive to a certain extent, and the corresponding temperature and concentration need to be maintained during the injection.
5. Packaging
The last step is the packaging of the battery. The electrodes and electrolyte are placed in the battery shell and sealed, so that a complete lithium battery is made.
Battery packaging is relatively simple, and only requires charging, testing and other processes. In order to ensure the quality and stability of the battery, safety regulations must be strictly followed during the packaging process to ensure the normal use of the battery.