Qoose
Enlightened
If this isn't quite the right forum, feel free to move. Flashlight is defined as a battery powered light source though...
I'm sure many of you have heard of LED throwies. If you haven't google is your friend. Another way to think of it is a keychain light, only with no plastic shell. Now I want to make a simmilar little guy, only using a CR123 and possibly a resistor. I want it to last for at least a few months. I'm using this to make a cool display, and no it will not be graffiti/harmful to the enviroment. It only needs to be bright enough that the LEDs can be seen when looking directly at them.
Now I already made a prototype, run off a partially drained CR123. Using a really nice multimeter that I got as a gift, I found it drawing 2.8ma. If this was constant, then it shouldn't have lasted more than 200 hours assuming that the battery was under 1/3 full. However, it glowed for about 3 weeks. I didn't meter it when it got darker though, so I suspect that current and voltage dropped which let it stay alive for much longer.
I was using a used Tenergy cell without a resistor. I strung one LED lead through the vent holes, twisted and glued. Then I peeled off the wrapping, and used the body as the negative contact.
My question is this. Is it safe? This is a tiny load on the cell, but is there any chance of a venting/meltdown? I don't want my piece of art to become a bomb.
Next, I'm thinking of soldering my next ones together, but just the positive contact, to the lead. Would it be bad if I soldered to the battery?
Also, would a resistor burn off energy, and would it be better to just find the dimmest LEDs I can buy, and drive them directly?
Last, where is the cheapest that I can get 50ish cells, and would these cheap cells be safe under this tiny load?
I'm sure many of you have heard of LED throwies. If you haven't google is your friend. Another way to think of it is a keychain light, only with no plastic shell. Now I want to make a simmilar little guy, only using a CR123 and possibly a resistor. I want it to last for at least a few months. I'm using this to make a cool display, and no it will not be graffiti/harmful to the enviroment. It only needs to be bright enough that the LEDs can be seen when looking directly at them.
Now I already made a prototype, run off a partially drained CR123. Using a really nice multimeter that I got as a gift, I found it drawing 2.8ma. If this was constant, then it shouldn't have lasted more than 200 hours assuming that the battery was under 1/3 full. However, it glowed for about 3 weeks. I didn't meter it when it got darker though, so I suspect that current and voltage dropped which let it stay alive for much longer.
I was using a used Tenergy cell without a resistor. I strung one LED lead through the vent holes, twisted and glued. Then I peeled off the wrapping, and used the body as the negative contact.
My question is this. Is it safe? This is a tiny load on the cell, but is there any chance of a venting/meltdown? I don't want my piece of art to become a bomb.
Next, I'm thinking of soldering my next ones together, but just the positive contact, to the lead. Would it be bad if I soldered to the battery?
Also, would a resistor burn off energy, and would it be better to just find the dimmest LEDs I can buy, and drive them directly?
Last, where is the cheapest that I can get 50ish cells, and would these cheap cells be safe under this tiny load?
