Product Review: DIY Mini Spot Welder

By John Slaughter WB5HSI

Recently I was faced with trying to repair a battery-operated device and had the usual problem of how to make connections to the battery.  Normally a spot welder is used to weld nickel strips to the battery terminals.  While it is possible to solder to a battery, it is not recommended and with Li-ion batteries there is the real risk of uncontrolled discharge and fire due to the flammable electrolyte.

DIY Mini Spot Welder with 4 Output Power, Household DIY Nickel Belt Portable 18650 Spot Welder with Aluminum Alloy Shell and 2Pcs x Welding Pen.

I found this device on Amazon and at $72 seemed a little pricey, but I found at least one review on YouTube which was encouraging, so I ordered one.  Many other similar items for less money may be found on eBay.  I found the identical item on AliExpress for $40.55. 

No English language instructions were provided, but between the description on the Amazon page and Google Translate, I was able to figure out how to operate the unit. 

Results so far are good.  I was able to weld nickel strips to an AA battery easily and to a few other items in the shack including a PL259 shell and the body of a small transformer.  I was also able to weld a strip to a piece of plated steel.  You cannot weld to aluminum with this device.  There have been many times when I have found electrical items very difficult to solder.  It is very easy to solder to the nickel strips. 

Your mileage may vary!
John, WB5HSI

Welding a tab to a battery