A cell phone battery can really hurt you if you fuck around with it, but even then you probably won’t be injured if you’re careful and paying attention to the obvious warning signs (fizzing, gasses, small flame) the precede the jets of flame that could burn you.

A CR1616 has less than 1 percent of the energy of a cell phone battery, and is less volatile. Even in a worse case scenario it could pop and startle you, but if you’re wearing gloves and safety glasses and rinse off any chemicals that may hit your skin immediately, you’ll be just fine. Be cautious, not afraid with these.

I’ve done this before on a Pokémon silver cartridge. Instead of soldering the tab back on, I carefully taped it in place. It works just fine. The fit of the board into the plastic case might be different on the advanced cartridges so I’d say use your best judgment but it will work if it’s just held there instead of soldered.

To remove the soldered on tab, I just used a tiny screwdriver (like for eye glasses) and removed it.

The nice part with this is you can just change the battery if it goes dead again.

Working on power supplies is dangerous because they have giant capacitors that store a LOT of energy that can discharge very quickly. It can kill you. You need equipment to safely discharge the capacitor and need to know what precautions to take but often it isn’t worth the hassle and risk.

Working on a small battery like this isn’t very dangerous. The real risk is ruining the cart because of amateur soldering. If you are comfortable with your soldering skills then go for it.

The three issues are:

• heating some of the ICs or shorting something on the board with that puddle of solder

• Static shock to the board

• Putting the battery backwards

So, if you are somewhat careful with the soldering iron and have a fine tip like pictured here and take some static precautions, it should be fine. I don’t think anything would be permanently damaged by putting the battery backwards, you would just have to repeat the procedure. With consumer boards that have somewhat exposed pads like this, I think it should be good enough to touch a grounded piece of metal before handling the board, as they should be made with people handling them in mind. But that is just my two cents.

Those coin cell batteries are typically alkaline so they don’t explode like Li-Po or Li-ion.

When you buy those battery kits, they have the tabs already tacked on so you’re not soldering directly to the battery. For the tab aspect, you still cant go all gorilla on it and use a propane torch but with a real iron it’d be fine.

The big thing I see with a lot of people new to electronics is they want to jump right into fixing their prized possession, sorta like people who want to get into fixing watches that they found in great grandpappy’s sock drawer. To do this right, you want a good soldering iron with temperature control and some practice boards. They sell tons of kits for this. You can get yourself a blinky little circuit board and feel a lot better about screwing around with hot metal.

Electronic components can typically handle a lot more heat than you’d think.