Power Tools Internal battery Replacement

Start by removing the 4 screws using the TR10H

Set the screws aside

Pry the two shells apart. It may be difficult to open, and it may require that you use a flat-head screwdriver to help pry it open.

There is a spring inside that is used for the locking mechanism, which is not secured and will fall out when the device is opened. Marked in orange

Remove the battery from the bottom shell. There may be glue, or it may be difficult to remove; use the pliers to help remove the battery pack. Areas that pliers can safely hold onto the pack are marked in green.

USE caution not to puncture the batteries, as they can release toxic fumes or may start a fire

Use a multimeter to determine if any battery cells can be reused. But since the terminals read zero, which means that my cells no longer have voltage.

If your cells have voltage, the safe operating range of 18650 batteries is 2.9V and 3.8V

Use caution when desoldering. Excessive heat to the batteries, even at zero voltage, can still release toxic fumes and cause a fire.

Use proper ventilation and a work station. A recommendation is to use a chisel tip for the soldering iron to heat the solder. And use a copper wick to remove the solder.

The main power lead (Red and Black wire) solder joint may use a solder that requires greater heat than the solder iron can provide. Use pliers to remove the nickel strip from the battery

Since the Main leads are not in a desirable condition, I will cut and add a new nickel strip to the main power leads

Start by noting the polarity of the batteries and how they are connected

Then, by carefully removing the nickel strip from the batteries using pliers

Dispose of the batteries following your area's battery disposal procedures.

Add the new batteries in the polarity that you noted

Use safety glass when spot welding, as sparks may fly

Set your spot welder to the appropriate settings when welding the batteries, as the heat can puncture them

Since the batteries that I'm using have a separate cable, you may have to cut a smaller nickel strip to reconnect the cable marked in red

To reconnect the main power leads, add a new nickel strip by spot welding the strip to the power lead. Shown in orange

Re-solder the cables removed in step 5

Place the battery pack into the case, the 4 screws, and the spring

And test to see if it charges ( My battery shows blinking, so I know it is charging)