I need to know the best way of dealing with excessive current drawn through CR123s.
I am experimenting with 20W and 50W 12V halogen bulbs and a stack of CR123s. I am overdriving the bulbs to 15V with one extra CR123 cell. The bulbs seem to handle it without complaint. The cells cannot handle the current, though.
Tonight I ran 5 CR123s in series through a 50W bulb. The cell temperature climbed steadily to 100°C+ over the course of 10 mins, before one popped, spewing its grey molten guts in a fine spray. Up until that point, the head cast a beautiful uniform intense yellow-white light with no hot-spot. In terms of lighting and longevity, it's all I need, but I don't like my cells exploding at random.
I then ran a duplicate cell pack through the 20W bulb, and they seemed to handle that fine. The temp peaked at 59°C and the lux dipped after about half an hour. That'll do for me in terms of longevity, but the light output is a bit weak.
What I learned was that I need the 50W bulb, but with the (per cell) current flow of the 20W bulb.
For my next experiment, I plan to run two 15V chains of CR123s and wire them in parallel. Now, if the cells aren't uniformly charged, the circuit could make one stack charge the other with unhappy results.
As a safety, I could put in two protection diodes. Do I have to? Is it safe in any case?
Advice appreciated,
Dan
I am experimenting with 20W and 50W 12V halogen bulbs and a stack of CR123s. I am overdriving the bulbs to 15V with one extra CR123 cell. The bulbs seem to handle it without complaint. The cells cannot handle the current, though.
Tonight I ran 5 CR123s in series through a 50W bulb. The cell temperature climbed steadily to 100°C+ over the course of 10 mins, before one popped, spewing its grey molten guts in a fine spray. Up until that point, the head cast a beautiful uniform intense yellow-white light with no hot-spot. In terms of lighting and longevity, it's all I need, but I don't like my cells exploding at random.
I then ran a duplicate cell pack through the 20W bulb, and they seemed to handle that fine. The temp peaked at 59°C and the lux dipped after about half an hour. That'll do for me in terms of longevity, but the light output is a bit weak.
What I learned was that I need the 50W bulb, but with the (per cell) current flow of the 20W bulb.
For my next experiment, I plan to run two 15V chains of CR123s and wire them in parallel. Now, if the cells aren't uniformly charged, the circuit could make one stack charge the other with unhappy results.
As a safety, I could put in two protection diodes. Do I have to? Is it safe in any case?
Advice appreciated,
Dan