Silviron
Flashlight Enthusiast
We have kind of brushed up against this topic on several different threads, But I don't remember a separate topic on it , so here goes:
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Daniel Ramsey:
.... I'll give a hint as to where I am heading, try using a good sized modern laptop battery setup.check out some specs of voltage/current out and mA ratings.<HR></BLOCKQUOTE>
Funny you should mention this today- I just started a run-time test on some laptop battteries- I had to rebuild my laptop battery anyway, so ordered extras to experiment with-
I'm using some Sanyo HR-4/3A NiMH batteries- 1.2V @ 3800 MAH each in a 67.5mm X 17 mm package. Three of them in series make a 2 X 2-5/8 x 3/4 inch "3.6V" battery pack.
Have been running a LS/O ( on a too small piece of heat-sink I had laying around, with a 1.2 ohm resistor on it) for 4 hours so far, and they seem to be working great.
Here are the results to this point in time:
{not set up to do current readings the way I have it wired, sorry.}
Start: 4.35V No Load from batteries, 4.17 V in front of resistor, 3.31V at LED. 250 LUX @ 1m, 63,000 LUX with LED in contact with meter sensor. Running a little too hot for my taste, so I put it in the freezer rather than digging out a better heat sink
1hour: 3.8V No load, 3.7V in front of resistor, 3.171V at LED. 220 / 57,400 LUX.
Back in freezer.
2 hours: 3.814v No Load, 3.755V in front of the resistor and 3.167V at the LED itself. LUX @ 1meter =210. LUX at contact with sensor: 55,000. Turn off to sleep.
Back on 6 hours later: Put on metal file cabinet to aid heat dispersion rather than using freezer
3 Hours: 3.975V No Load, 3.731V in front of resistor, 3.159 V at LED. 210 /55,400 LUX.
4 Hours: 3.75 V No load, 3.74V before resistor, 3.15V at LED. 200 LUX @ 1 Meter, 54,800 LUX with LED in contact with meter sensor.
Will post later test data if anyone is interested. I'm also messing with some Li - Ions, although I haven't done any "serious" tests yet on them...
P.S. I got the 4/3A s from House of Batteries, fifty dollars for ten, so they are a reasonable cost replacement for sub-C through D cells, in a less bulky package.
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Daniel Ramsey:
.... I'll give a hint as to where I am heading, try using a good sized modern laptop battery setup.check out some specs of voltage/current out and mA ratings.<HR></BLOCKQUOTE>
Funny you should mention this today- I just started a run-time test on some laptop battteries- I had to rebuild my laptop battery anyway, so ordered extras to experiment with-
I'm using some Sanyo HR-4/3A NiMH batteries- 1.2V @ 3800 MAH each in a 67.5mm X 17 mm package. Three of them in series make a 2 X 2-5/8 x 3/4 inch "3.6V" battery pack.
Have been running a LS/O ( on a too small piece of heat-sink I had laying around, with a 1.2 ohm resistor on it) for 4 hours so far, and they seem to be working great.
Here are the results to this point in time:
{not set up to do current readings the way I have it wired, sorry.}
Start: 4.35V No Load from batteries, 4.17 V in front of resistor, 3.31V at LED. 250 LUX @ 1m, 63,000 LUX with LED in contact with meter sensor. Running a little too hot for my taste, so I put it in the freezer rather than digging out a better heat sink
1hour: 3.8V No load, 3.7V in front of resistor, 3.171V at LED. 220 / 57,400 LUX.
Back in freezer.
2 hours: 3.814v No Load, 3.755V in front of the resistor and 3.167V at the LED itself. LUX @ 1meter =210. LUX at contact with sensor: 55,000. Turn off to sleep.
Back on 6 hours later: Put on metal file cabinet to aid heat dispersion rather than using freezer
3 Hours: 3.975V No Load, 3.731V in front of resistor, 3.159 V at LED. 210 /55,400 LUX.
4 Hours: 3.75 V No load, 3.74V before resistor, 3.15V at LED. 200 LUX @ 1 Meter, 54,800 LUX with LED in contact with meter sensor.
Will post later test data if anyone is interested. I'm also messing with some Li - Ions, although I haven't done any "serious" tests yet on them...
P.S. I got the 4/3A s from House of Batteries, fifty dollars for ten, so they are a reasonable cost replacement for sub-C through D cells, in a less bulky package.
