The solution to the problem of bulging at the same solder joint when welding a lithium battery with a nail welding machine is as follows:
1. Solder joints are protected by argon gas and are not. discolor. You can grind the solder joints with a grinder to remove traces of the solder joints. Remove it and polish it with a polishing machine.
2. Use an angle grinder and a metal grinding wheel to remove traces of solder. Use epoxy resin glue and white cement to make a paste and apply it to the pitted points of the tiles. Remove excess glue with a shovel. The angle grinder is equipped with a polishing wheel for polishing.
If you are using an electric welder to convert aluminum tabs to nickel strips, you can use Violin 303B solder to flatten them, then solder to prevent heatur generated by spot welding at the part to be welded. The temperature is 400 degrees. For testing and further use, you can usually use an electric soldering iron to solder directly with M51 low temperature soft solder and use M51-F flux for soldering. The temperature may be higher when using a spot welder.