Precautions for Lithium Battery Welding Process
1. Ultrasonic metal spot welding of lithium battery
Since the positive pole of the lithium battery pack cell is made of aluminum tape, it cannot be soldered directly, so it needs to be connected with nickel tape. , Ultrasonic metal spot welding is usually used: the use of ultrasonic to generate high-frequency oscillations causes the friction between the two metal sheets to locally generate high heat, and they are fused and connected. Frequency: 20K~35KHZ Time: 0.3/S
Attention should be paid to selecting suitable welding equipment for metal ultrasonic welding machine. Take care to use proper welding parameters.
Prevent the positive aluminum strip from being over-welded, otherwise it will break easily. Prevent the positive aluminum strip from being welded firmly, otherwise the battery will be easily cut off;
2, the solder connection of the lithium battery
The main principle: use the soldering iron to heat the solder wire to melt the tin The material adheres to the welded part and connects after cooling.
1) Classification of soldering irons:
A. Internal heating type and external heating type, internal heating type soldering iron heats up quickly.
B. Ordinary soldering iron, temperature regulating soldering iron, anti-static constant temperature soldering iron.
2) Soldering iron power: 30W, 35W, 40W, 50W, 55W, 60W, 65W, etc.
3) Soldering iron temperature: Set according to the area of u200bu200bsoldering tin and the amount of tin used. If the temperature is too low, the tin wire cannot be melted quickly, which will affect the welding speed. If the temperature is too high, the solder joints will not be smooth. The temperature of the soldering iron is generally set at 360℃±10℃
4) Welding posture: generous and natural, sitting posture is correct.
5) Welding techniques: there are pen-holding methods and straight-holding methods.
6) Welding angle: The welding angle of the pen holding method is between 30° and 60°. The best angle is 45° between the tip of the soldering iron and the object to be welded.
7) Solder composition: tin (Sn) 60~63%, lead (Pb) 40~37%, rosin 1.0%~1.2%
Some companies have begun to use it Lead-free solder
8) Soldering time: <3S
9) Method: first put the soldering iron on the part to be soldered, and then put the tin wire in the gap between the tip of the soldering iron and the part to be soldered.
10) Welding volume: a proper amount of tin can cover the object to be welded 10) Welding quality: solder joints are bright and uniform, firm, without tin connection, missing solder, no false solder, no porosity, and can’t afford it. Floor. The size of the solder joints is related to the amount of contact hot tin;
3. Super-welding process and requirements of the lithium battery shell
1) The package connection of the shell generally adopts the ultrasonic plastic welding method.
2) Working principle: Using ultrasonic to generate high-frequency oscillations to cause friction between the upper and lower shells, local temperature rises to generate high heat, and the 'plastic flow' of the material will be generated between the two rubber parts, which will be cured under pressure , And the formation of all welded.
3) Choose the appropriate ultrasonic welding machine,
4) Use the appropriate welding parameters: power factor: force × speed, force has pressure (air pressure), descending speed. The rate has frequency and amplitude, energy u003d power × time frequency: 20KHZ welding time, pressure holding time.
5) The design of the shell and the protection board should pay special attention to the size matching to prevent the super not in place or super tight.
6) The thickness of the protective plate and the layout of the components should fully consider the impact of ultrasonic waves to prevent the components from being shaken loose.
7) Affect the welding effect: plastic materials, welding design, molds, etc.
8) Super welding quality: no super damage, no glue, no super height, uniform welding wire, close welding, the sample falls on the board at a height of 1m, and the X, Y, and Z sides fall each Meet the requirements once (six times in total).
Shenzhen Chuangneng Ruiyuan Electronics CO.,LTD. has an array of branches in domestic for munufacturing custom lithium ion battery.
As President of Shenzhen Chuangneng Ruiyuan Electronics CO.,LTD., I am committed to the enduring values of integrity, accountability, innovation and flexibility, value creation and social responsibility.
Shenzhen Chuangneng Ruiyuan Electronics CO.,LTD. must adopts new technology and internal procedures to increase responsiveness and mitigate costs going forward.