Production process of battery components

(1) Battery test
Due to the randomness of the battery manufacturing conditions, the performance of the batteries produced is not the same, so in order to effectively combine batteries with consistent or similar performance, they should be classified according to their performance parameters; battery testing is to test the output of the battery. The size of the parameters (current and voltage) classifies it. In order to improve the utilization rate of the battery and make battery components of qualified quality.
(2) Front welding
The bus strip is welded to the main grid line on the front side (negative electrode) of the battery. The bus strip is a tinned copper strip. The welding machine we use can spot weld the strip on the main grid line in the form of multiple points. The heat source used for welding is an infrared lamp (using the thermal effect of infrared rays). The length of the welding tape is about 2 times the length of the side of the battery. The extra welding tape is connected to the back electrode of the rear battery when the back is welded.
(3) Back connection
Back welding is to connect the batteries together in series to form a component string. The process used is manual. The positioning of the battery mainly relies on a membrane plate with grooves for placing the batteries. The size of the grooves corresponds to the size of the battery. The position of the grooves has been designed. Different templates are used for components of different specifications. The operator uses an electric soldering iron and solder wire to solder the front electrode (negative electrode) of the "front battery" to the back electrode (positive electrode) of the "back battery", so that they are connected in series together in sequence. The leads are welded to the positive and negative electrodes of the component string.
(4) Lamination laying
After the back surface is connected in series and has passed the inspection, lay the component string, glass and cut EVA, glass fiber, and backplane according to a certain level and prepare for lamination. The glass is coated with a layer of reagent (primer) in advance to increase the bonding strength of the glass and EVA. When laying, ensure the relative position of the battery string and glass and other materials, adjust the distance between the batteries, and lay a good foundation for lamination. (Laying level: from bottom to top: tempered glass, EVA, battery, EVA, glass fiber, backplane).
(5) Component lamination
The laid battery is placed in a laminator, the air in the component is evacuated by vacuuming, then heated to melt the EVA to bond the battery, glass and backplane together; finally cooled to take out the component. The lamination process is a critical step in the production of components, and the lamination temperature and lamination time are determined according to the nature of the EVA. When we use fast curing EVA, the lamination cycle time is about 25 minutes. The curing temperature is 150 ° C.
(6) Trimming
During lamination, EVA melts and solidifies outward due to pressure to form burrs, so it should be cut off after lamination.
(7) Framing
Similar to installing a mirror frame for glass; installing an aluminum frame for the glass assembly increases the strength of the assembly, further seals the battery assembly, and prolongs the service life of the battery. The gap between the frame and the glass assembly is filled with silicone resin. Connect the frames with corner keys.
(8) Welding junction box
Solder a box at the leads on the back of the component to facilitate connection between the battery and other devices or batteries.
(9) High voltage test
High voltage testing refers to applying a certain voltage between the component frame and the electrode leads to test the voltage resistance and insulation strength of the component to ensure that the component is not damaged under harsh natural conditions (lightning strikes, etc.).
(10) Component testing
The purpose of the test is to calibrate the output power of the battery, test its output characteristics, and determine the quality level of the component. It is mainly to simulate the test Standard test condition (STC) of sunlight. Generally, the test time required for a panel is about 7-8 seconds.