This is a little module I made some time ago. It's designed to be used for temporary illumination of garden features and uses a protected lithium cell to run a cluster of LEDs.
The choice of a protected lithium cell is to ensure it switches itself off when the voltage is low to prevent cell damage.
Each LED has its own resistor (I used 47 ohms for these Gallium Nitride green superflux LEDs).
The module has spacers fitted to the bottom of the PCB to avoid getting shorted out on metal surfaces.
In use a charged cell gets put into the holder and the whole illuminated module gets placed inside a clear or translucent Tupperware style food storage container that is watertight.
The enclosed module then gets placed where the illumination is required. After use the module is removed and the cell recharged.
The choice of a protected lithium cell is to ensure it switches itself off when the voltage is low to prevent cell damage.
Each LED has its own resistor (I used 47 ohms for these Gallium Nitride green superflux LEDs).
The module has spacers fitted to the bottom of the PCB to avoid getting shorted out on metal surfaces.
In use a charged cell gets put into the holder and the whole illuminated module gets placed inside a clear or translucent Tupperware style food storage container that is watertight.
The enclosed module then gets placed where the illumination is required. After use the module is removed and the cell recharged.