In the field of electronic equipment and lithium batteries, cell is one of the most basic components. However, many people may wonder why cell cannot be directly soldering. This article will introduce shao cell cannot be directly soldering and explain the details.

I. Cell structure

cell is generally composed of positive and negative electrode sheet, diaphragm, electrolyte and Shell. Among them, the positive and negative electrode sheet is composed of thin aluminum or copper foil and electrode materials (such as lithium iron phosphate, lithium cobalt oxide, etc.). This structure is prone to a series of problems in the process of soldering.

II. Effect of high temperature on cell

1. temperature sensitivity: cell the internal electrolyte may undergo evaporation, decomposition or electrochemical reaction at high temperature, resulting in cell performance degradation and even safety problems.
2. Thermal expansion: cell is prone to thermal expansion at high temperature, resulting in deformation or rupture of Int Comp, thus affecting the normal operation of cell.

III. Cell welding problems

1. melting point problem: the electrolyte and materials inside cell are easy to melt at high temperature, resulting in poor welding contact or short circuit.
2. Conductivity: during soldering, cell positive and negative electrode sheets may react with solder to form oxide or other compounds, resulting in increased resistance or loss of conductivity.

IV. Cell protection

to ensure the safety and stable performance of the cell, the following protection measures are usually taken without direct soldering.

1. Welding materials: special welding materials, such as lead-free solder, have low melting point, which can reduce the thermal effect on cell.
2. Welding method: indirect welding method is adopted, that is, connecting with cell through wires to reduce direct heat conduction.
3. Welding temperature control: control the welding temperature to avoid adverse effects on cell caused by high temperature.

V. Alternative solutions

in order to solve the problem that cell cannot be directly soldering, there are currently some alternative welding methods, such:

1. spot welding: use spot-welder to spot weld cell with wire to achieve reliable connection.
2. Hot pressure welding: use high temperature and pressure to connect cell with the wire to avoid using solder.

The reason why cell cannot be directly soldering is mainly due to factors such as cell structure, the influence of high temperature on cell and welding problems. In order to ensure the safety and stable performance of cell, it is necessary to take appropriate protective measures and replace welding methods. In the production and assembly process of cell, strict control of temperature and selection of appropriate welding materials and methods are all important links to ensure the quality and reliability of cell. With the progress of science and technology and the deepening of research and development, more advanced and reliable cell welding technology may appear in the future.