LED lamp, credit card size

thingiverse

Simple 1W LED rechargeable lamp. Bigger version of https://www.thingiverse.com/thing:4805916, using TP4056 charger board. Easy assembly. Parts : Li-Ion (any old phone) battery max. 70x40x5mm, power LED 1W white, coolplate, reflector 22mm, TP4056 micro USB module (modified charge current, resistor 6K8), resistor 1 ohm to 3.3 ohm, round 8mm torch switch, thin enamel wire, some thin string. Use the most common TP4056 module 18x23mm size. Replace the 1k2 SMD resistor on pin 2 with 6k8 in order to reduce the charge current. After assembling the LED, coolplate, and reflector, solder the LED + to switch centre. Connect switch rim contact to TP4056+ and a resistor with value 1 ohm (max lumens) or 3R3 (less light, lasts longer) to TP4056-. Solder the battery to TP4056. Pull the carry string in and tie a knot. The LED current is 200-300mA, giving 2-3 hours continous light with a charge. Charge time is about 4 hours. The charge LED shines through the case wall. Back is held by a wedge in position, notch at the USB plug side.