Make a Old Flashlight Glow Again

Upgrade an old flashlight with a modern LED, a 18650 Li-ion battery and USB-C charging.

What you need :

• An old flashlight
• 3W LED module for Arduino
• TP4056 Lithium Battery Charging Board 1A Type C BMS
• 18650 Li-ion battery 3.4 Ah
• battery coupler for one 18650
• 2mm bolts

Cut the top of the reflector and left part of the bulb socket.

Disassemble the reflector and unsolder the LED on the module.

Then place the LED inside the reflector and solder it to the module left behind.

Reassemble the reflector.

Drill the side of the lamp for the USB-C socket.

Fasten the battery coupler with 2mm bolts.

Fasten the charging board with an insulation plate underneath if the body of your lamp is metal.

Connect the LED module and the battery to the charging module.

BE VERY CAREFUL TO MAKE A CORRECT INSULATION AS A SHORT CIRCUIT CAN CAUSE AN BATTERY EXPLOSION.

Connect the switch to the +Bat and the command line of the LED module.

You can insert a resistor and an insulation plate for more safety.