Why do rechargeable button cells use laser welding technology?

Recent years, after the explosion of TWS headphones, new rechargeable button batteries with the advantages of long running time, high security and personalization have been unprecedentedly popular in various small wearable devices such as hearing aids, electronic tags, GPS, sensors, smart watches, smart glasses and smart speakers.

Button cell is also known as a button battery or rechargeable coin cell, the biggest advantage is good consistency, no bulging problems in the charge and discharge cycle, which can be set to a larger battery capacity and directly laminated to the PCB board. New rechargeable button cell battery to achieve fast charging technology, to meet the needs of certain special applications, not only environmentally friendly, but also can be recharged and used.

With the deep development of 3C electronics industry, customers put forward higher requirements for battery safety, and subsequently in the production process, production line equipment also put forward higher requirements, so most of the current market production of rechargeable steel-cased coin cell batteries are using laser welding technology, that rechargeable steel-cased coin cell batteries why the use of laser welding technology, do you know it, the following Grepow for everyone to Reveal the secret.

Fig.1

What is the button battery laser welding application process？

● shell and cover: button steel shell laser etching;

●  Cell segment: coil core positive and negative poles and shell cover welding, shell cover and shell laser welding, sealing nail welding;

● Module PACK section: cell screening, side gluing, positive and negative pole welding, post-welding inspection, dimensional inspection, adhesive paper on and off, air tightness inspection, and sorting off.

Rechargeable steel-case button battery why use laser welding technology?

1. Traditional welding processing technology is difficult to achieve the new rechargeable button battery high standard welding indicators, in contrast, laser welding technology can meet the button battery processing technology with diversity, such as heterogeneous materials (stainless steel, aluminum, copper, nickel, etc.) welding, irregular welding trajectory, more detailed welding points and more accurate positioning welding area, etc., not only to improve the consistency of product welding, but also to reduce welding It is the best way to weld button batteries.

2. The positive and negative electrodes and shell cover welding, copper conductivity is good, but highly reflective material, the laser absorption rate is very low, coupled with the material is extremely thin, in the heat area is too large, too long or laser power density is not enough, it is easy to deformation, resulting in poor welding.

Top cover sealing welding, button battery shell and cover connection after processing the thickness of only 0.1mm, the traditional welding can not be achieved. Laser welding power is too high will directly penetrate the battery case, injuring the internal core and the material is very easy to deformation, low power is unable to form a molten pool to achieve the purpose of welding.

The pins are usually welded through the finished battery in a stacked manner. In the execution of this welding process, the battery has been encapsulated, and the battery is filled with electrolyte inside, if the welding process is not stable, it is easy to cause the internal diaphragm welding bad cause short circuit, or the battery shell welding through, resulting in electrolyte outflow, false welding, over-soldering and other undesirable phenomena.

3. Laser welding technology is suitable for automatic assembly and welding manufacturing of steel-cased button batteries; modular design, compatible with 8-16mm button battery cell assembly manufacturing, to achieve production line data traceability.

Fig.2

4. Laser welding technology equipment can be from the cell screening data upload, to the welding process of lamination accuracy control, welding energy detection and a full set of processes to achieve fully automatic assembly welding, to ensure efficient product output; high-precision laser lamination welding technology, welding real-time monitoring technology, visual size sorting technology to ensure high quality welding, taking into account the high precision size control, with higher reliability and stability The welding rate reaches 99.5%.

5、Grepow adopts laser welding technology equipment with data traceability function to ensure accurate tracking and binding of the product production process, and can later retrieve relevant data for viewing to ensure product quality.

The above is the rechargeable steel case button battery why the introduction of laser welding technology, I believe that through the above introduction you have a certain understanding of the rechargeable steel case button battery using laser welding technology, Grepow as one of the rechargeable button battery manufacturers, the company through continuous upgrading iterative technology, the formation of the core technology of the patent group, to achieve the production capacity and process of supporting the upgrade, the continuous launch of the High-performance GRP1254, GRP1054, shaped button battery, custom button battery solutions to help the development of audio, smart wear market!