Just did a highly inaccurate measurement of my C8 and the hotspot seems to be roughly 38cm across at 5 meters or +–2 degrees or a 4 degree cone. I wonder how collimated the GT’s beam is?
PSA - Cells pulled from recent (less than 2 years old) Teslas appear to be derived from the NCR18650GA, but have additional Tesla “special sauce” added that appears to improve cycle life considerably, as well as survive abuse considerably better than most other cells. I’ve got a couple test cells I’ve cycled from 4.25 to 0.0v and back (clamped in dead short for 24 hours after 5A discharge to 0.5v) and after 10 cycles like that, they’re still within 50mAh of the non-abused cells. Also notable is internal resistance drops considerably with heat - unlike most cells that only seem to noticeably show this below 0C, the cells I’ve tested have a pretty significant lessening of voltage sag above 40C.
Like the normal NCR18650GA, not optimal for high current applications, but if you don’t need a 30Q, it’s really hard to beat these. I’ve bought mine from the guy below, but they’re pretty common on ebay now as well. Previous wrapped cells I’ve gotten from him did need a solder blob to work with lights like the Q8. I’ll report when I get my latest order if the current ones are the same.
What?!
Please make a topic about this
I am sure lots of people don’t read the GT thread and what you write is very interesting (and a bit weird)
This deserves a deeper talk
(Me thinking about dangers of under voltage dendrites is something id like to read smarter people react to)
No time right now for a solid write up, but once I get the new cells in (my previous cells were from a P85, no silicon in the anode that I’m aware of) I’ll be doing a bunch of tests and can do a better write up then. I’ll also dig up the old 0.0v test cells and see how much they’ve degraded over the past year.
I might attempt more destructive tests on the new batch too. (I say attempt because past attempts with a jumper cable were just that, no fire, just a really hot cell, and one that made a “click” noise and went open circuit)
I bought 8 30q cells but accidentally ordered flat top. Hoping I can make them work. Figure a little magnet or something should do the trick but I’m hoping the carriers wind up working with flat tops. Oh well, live and learn I guess, got a great price so worst case I’ll get 8 more and repurpose these.
The way a carrier is loaded pretty much excludes a magnet top, it’s been said that the isolation disk can be removed to make flat tops work but you’ll have to be sure you observe proper polarity when inserting cells, it’ll be on you if you invert one accidentally.
Those are awesome shots Pommie. You can see the pylons beside the road or pier which ever it is all the way down. This thing really is a monster thrower. Thanks for sharing them!
Rick
It’s my understanding, ccc, that the carriers have been modified and the driver contact board is being adjusted to suit… the team doing the hover propulsion unit has already gone on vacation so that might be a while.
Teacher, if my son was given transport duty of such a light, the global scientists would think that our planet was going Pulsar or something, the spastic flashes of intense beams would fluster them all. (He cannot be still to save his life!)