The Wurkkos DL46 is a flashlight with a built-in battery that isn’t meant to come out. I bought one on eBay sold as-is because someone had ripped the battery out of it. Its leads had been pulled off the cell, leaving the battery loose from the driver board.

Getting it working again comes down to opening the front end, putting the cell back in the body, and resoldering the board’s leads onto the cell tabs. Here’s how I did it, step by step.

# What you need

* A small Phillips screwdriver
* A soldering iron and solder
* The flashlight’s rubber O-ring, which sits on top of the battery

# Step 1: Peel off the front sticker

The front end, which faces the same way as the light, is covered by a plain black sticker. Peel it off to find two screws holding a black plastic cover over the board. The cover has holes for the five charge-indicator LEDs, a small opening for the button, and a keyhole opening for the gold contact.

The flashlight’s front end with its black sticker removed, showing a black plastic cover held by two screws around a gold contact pad. *With the sticker peeled off, two screws hold the black plastic cover over the front end.*

# Step 2: Remove the plastic cover

Take out the two screws and lift off the cover. Underneath is the circuit board, marked `DL46_C-B0`, with the USB-C port, the button, and the indicator LEDs.

A green circuit board inside the flashlight body with a USB-C port, a push button, five indicator LEDs, and three screws. *Under the cover, the board with the USB-C port, button, and charge LEDs, held in by three more screws.*

# Step 3: Unscrew the board

Three more screws hold the board to the rim inside the body. With those out, the board lifts free on its battery leads, showing the MOSFETs and inductor on its underside.

# Step 4: Put the cell back and resolder the leads

Slide the battery back into the body, then solder the board’s two leads back onto the cell tabs. Check polarity before you solder, since reversing the leads on a driver board like this can damage it:

* **Positive:** the metal tab on the battery board.
* **Negative:** the wire coming off the edge of the battery board.

A hand holding the driver board above the flashlight body while two black wires run down to a metal tab on the battery inside. *The cell back in the tube, with the board’s leads going back onto the battery tabs.*

# Step 5: Seat the O-ring

This is the step that’s easy to miss. The thick rubber O-ring goes between the battery and the rim the board screws into, and it keeps the cell from moving around inside the body. Without it, the battery can shift and pull on the new solder joints.

# Step 6: Close it up

Screw the board back onto the rim, put the plastic cover back on with its two screws, and the light is fixed.

Wurkkos DL46 Battery Resoldering Guide