polymer lithium battery.Cylindrical lithium battery technology, reasons for leakage of cylindrical lithium batteries

Cylindrical lithium battery technology, reasons for leakage of cylindrical lithium batteries. With the further expansion of the electric vehicle market and the increasing requirements for cruising range, vehicle manufacturers are focusing on power batteries in terms of energy density, manufacturing cost, cycle life and additional product attributes.

Cylindrical lithium battery technology, reasons for leakage of cylindrical lithium batteries. With the further expansion of the electric vehicle market and the increasing requirements for cruising range, vehicle manufacturers have put forward higher requirements for power batteries in terms of energy density, manufacturing cost, cycle life and additional product attributes. As long as there has not yet been a huge breakthrough in the field of raw materials, appropriately increasing the size of cylindrical lithium batteries to obtain more battery capacity has become an explorable direction. Today the editor will talk about the cylindrical lithium battery process and the reasons for leakage.

Cylindrical lithium battery production process flow

Objectively speaking, the lithium battery production process is divided into three major sections, one is pole piece production, the other is cell production, and the third is battery assembly. In the lithium battery production process, pole piece production is the foundation, battery core production is the core, and battery assembly is related to the quality of the finished lithium battery. The specific steps of the lithium battery production process include positive electrode slurrying, negative electrode slurrying, positive electrode sheets, negative electrode sheets, steel case assembly, liquid injection and testing, and packaging.

As we all know, the production process of lithium batteries is quite complicated. After all, the safety performance of lithium-ion battery products is directly related to the life and health of consumers. Naturally, the production and manufacturing of lithium batteries has high requirements on the performance, accuracy, stability and automation level of the equipment. .

Take the preparation of electrode slurry in the lithium battery production process as an example. This link is the most front-end link and the most important link in the entire production process. After all, the electrode slurry mixing and dispersion process has an impact on product quality of more than 30%. %. What's the reason?

The reason is that the preparation of positive and negative electrode slurries for lithium batteries includes a series of processes such as mutual mixing, dissolution, and dispersion of liquids and liquids, liquids and solid materials, and is accompanied by changes in temperature, viscosity, environment, etc. In the positive and negative electrode slurries, the dispersion and uniformity of the granular active materials directly affect the movement of lithium ions between the two poles of the battery, so the dispersion quality of the electrode slurry directly affects the product performance of lithium batteries.

Causes of liquid leakage in cylindrical lithium batteries

The main reasons are: excessive internal pressure and unqualified external packaging.

1. During the battery manufacturing process, if the following problems occur, it is easy to cause battery leakage:

1. When welding the battery casing and the cap, the welding is not firm, not sealed, there are leaks, weak welds, cracks, cracks and other problems in the welds.

2. When sealing with steel balls, the size of the steel balls is inappropriate and the material of the steel balls is different from the material of the cap.

3. The positive electrode of the cap is not riveted tightly and has gaps, and the elasticity of the insulating sealing gasket is inappropriate, not corrosion-resistant, and prone to aging.

2. Problems that may occur during use:

1. The battery is not original, the voltage is too high or the current is too large

2. The battery is often bumped during normal use, damaging the aluminum-plastic film, and the internal strength of the battery is insufficient.

How to deal with liquid leakage from cylindrical lithium batteries

▲Check the battery casing. In many cases, the casing is damaged due to unreasonable battery installation, welding slag in the battery box of the frame, and knocks caused by the low chassis of the frame.

▲Take off the cover and check whether there are traces of acid leakage around the safety valve, then open the safety valve and check whether there is flowing electrolyte inside the battery.

▲If there are no abnormalities in the first two steps, an air tightness test needs to be performed, that is, pressurizing and inflating in water to check if there are any bubbles. If there are any bubbles, it means there is something missing. If there are no bubbles, it means it is normal.

▲When charging, you need to observe whether there is flowing electrolyte, and if so, remove it.

Once you find the leak, use a knife to clean up the surrounding area, and use battery-specific glue to glue the leak firmly. The reason why battery leakage occurs has a lot to do with the quality of the battery itself. Therefore, users must look for genuine high-quality batteries during the purchase process.

It can be seen that all aspects of the lithium battery production process are closely related to product quality and safety. Each link in the lithium battery production process must be strictly and carefully managed in order to improve the safety performance of lithium battery products. . If lithium battery leakage occurs, users should also pay attention when using it.