At 5A discharge, the Aspire 18350 (HKJ's chart below is from the Vapcell version) starts at 3.7 V, going down from there during drainage of the battery. Assuming that the tailspring in your flashlight build is not bypassed, at 5A the spring alone will already cause more than 0.2 V voltage drop, the last 0.1 V will surely be lost elsewhere in the current path.
Yeah, but with optimized electrical path and a CC FET driver you will have the maximum output for quite a while.
Run it at 4 - 4.5 A and it will be longer with probably not much less output.
Is there a test of this LED on the forum yet?
Didn’t know (or remember) the Aspires sagged that much though.
With cheap springs you can apparently get away with it.
It looks like it starts at 3.7, but at the beginning it is close to 4.2 like all other batteries.
The surge current happens when the circuit is first closed, and this initial spike in current is what will blow an LED in the first few milliseconds.
This could be due to smoothing of the graph though, i was told the drop is instantly when i asked about the same phenomenon.
A large enough capacitor over the driver input could solve such problems though.
Depends on cooling.
The Driver had his black flat running at 4.5A in his xcalibur, and he had some graph showing how the output drops to 75% after a few seconds or minutes.
I got output increases to about 6 amps on my black flat because I was cooling it with a fan cooled CPU heatsink and liquid metal.
The CSLNM1.TG is basically just a better black flat as far as we know, so I would assume it can also do 6A or even more with appropriate cooling.
Say I would like to solder a coil inline with the one of the ledwires to dampen the surge voltage, what value would do the job?, would a coil recovered from an old buck or boost driver come near what is needed? Same for a cap across the ledwires, what value would work?
Also posting this here, so it may reach more people that are interested.
I just put the new OBF successor in my BLF GT Mini. The max I measured was 282k cd. But with a protected battery at 4.1V the current is already at 6A at the tailcap. I’ll see if I modify the firmware to reduce the max output to 80% PWM. But the LED scaled all the way up to 100%, so I’m wondering what the actual limit is.
Even at 3.65V battery resting voltage, I get 260k cd. So it was probably overdriven a lot.
Beam looks like this. Ideally the 2 rays limiting the hotspot should be parallel right?
No stock GT Mini. Double spring in the tail and single driver spring. With bypasses and low RI cell I can easily see this pull 8A at least. :sunglasses: Boom!
I guess that Panasonic GA is ok if it will not pass 6A mark in DD setup where this emitter starts to loose performance…
I tried this low current cell: LG 18650 BD1 (pink cell unprotected) and since that is 4.35V cell charged to 4.2V it did not passed 5.5A with Osram white so I guess if charged to 4.35V it would not pass 5.8-6A but I don’t have 4.35 charger to test that.