LI Battery connection

Thread Starter


Joined Jan 21, 2018
I have a coin battery LI/MnO2 for a small flashlight which is almost dead, want to replace it. Thought it would be a simple solder but looks like more i.e. there is a thin strip connected to it but not soldered, looks like a spot weld to me. How to replace this battery?


Joined Mar 19, 2019
I've had some success soldering wires to batteries by first roughing the battery end cap with an emery board or bit of sandpaper. Most are shiny and with a bit sanding they take on a matte/scratched surface appearance. Cleaned with 99% Isopropyl alcohol to remove any oils, flux, and solder. Yes, most are spot welded at the factory.


Joined Jan 23, 2018
Solder tabs will almost always pull right off of a battery. That has been my experience.
Poor quality batteries?

I buy about 20 CR2032's at a time. The website appears to be offline, but it was like 20 CR2032 for $20.00 USD or so postage paid. Postage eats into the cost. I can also buy them from somewhere else and have them shipped to a sattelite office and pay no pastage.
Thanks. Not sure if you were sending me a link or make/model?
There are too many out there. I bought a programed PIC and PCB's to build one that I liked. They have a generic name of a "capacitive discharge spot welder". I miss all of those niceties that I had a work. We had a Unitek welder that used tube.
Besides, the welder you need a handpiece od some sort. Copper tips like for most spot welders. It just so happens that the energy of the weld can be precisely set in Watt-s.

Our primary use was making K thermocouples, but we used a graphite block and struck the TC on it. It wont make R and S thermocouples either (platinum/platinum-rhodium). They need to be made with a torch.

It could do battery tabs though.

I saw one that used a car battery as a power supply.

One comment I have about batteries, is the battery sleaves are not heat shrink. They are a much thinner material.