For the past few months i have been working on this and i finally got some documentation and the prototype done.
This is a completely scratch designed flashlight that is powered by 18650 cells from old notebook battery packs.
It uses a fully custom circuit to drive the LED and manage the battery.
Fully 3D printed main body.
Dimmable in 31 steps, no PWM.
Rechargeable with a regular phone charger.
Uses a single 18650 Lihium Ion cell.
Battery level Indicator.
Three button interface.
Arduino IDE compatible microcontroller.
Full battery management and protection.
Light output: 197 Lumen.
Color temperature: 5000K
Color rendering index: 83
Efficiency at 100mA: 159 Lumen per Watt
Efficiency at 250mA: 119 Lumen per Watt
Heat was the biggest problem, the final version will have a temp sensor on the LED and my goal is still to upgrade it to two LEDs instead of one.
It runs up to about 75°C with two LEDs, which is too much for the used plastic.
But, while heat was a problem, it is not a great concern anymore after quite a few practical tests and measurements.
It produces around 1.5W to 3W of heat, which is quite a lot on a thing this small.
It is just a for fun project but i am thinking about a limited Kickstarter, Gofundme or other type of funding run.
Unless someone in china steals my idea beforehand and starts churning them out by the buttload
At the moment, yes.
But since the light is programmable the buttons can take any task i want.
It only has one hardwired function, the light can only be turned on by the middle button.
The processor will only wake up from the power down state if triggered by one external pin, the one the middle button is wired to.
But after that the button can take on any other function.
Yes, the texture of the thing is very much a design feature and not a manufacturing artifact.
But to be honest, initially i wanted to sand and smooth it.
Until i realized that the texture is slip resistant, it fits the whole idea rather nicely i think.
The next one is currently printing, there will at least be another two versions i think, this is far from over