Battery weight a good indicator of quality / capacity ?

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CRX
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wle wrote:
Old laptop cells are a good example of something a weight test would not detect.

Additionally, they are the most likely source of fakes.

Cells get old without selling, they get cheaper and cheaper by the month til someone buys then and then voila!

“9999 MAh 18650s! 10 for $10”

wle

Amazing how they rejuvenate and improve themselves with time and a new wrapper LOL

snakebite
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yes.
real cells are around the 44-48 gram ballpark.
way lower than that means junk and corrosive drywall dust.

mud_muncher
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Zebretta wrote:
CRX wrote:
I don’t think it’s capacitors being used, just very small lipo cells with capacity anywhere around 100 – 300mAh judging by the sizes so maybe 5-10% stated capacity if you’re lucky LOL

Ahhh…so the capacity would be WAY off?
thanks

I just bought a 10 pack of cheap cheap UltraFire 18650’s ($1.00 each) off of ebay and I guess I got lucky because they all consistently tested at 700mAh which is at least usable in my small 1000lm Cree flashlights.

Just put these in the bin or get a refund! If it is a “1000lm” light it will pulling either side of 3 amps out of that cell or up to 5c @ 700maH. That is up there with a high quality high drain cell from samsung, sony sanyo or panasonic. At the very least you will get very short run times or worse a chance of fire ect.

Angler
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Zebretta wrote:
I just bought a 10 pack of cheap cheap UltraFire 18650’s ($1.00 each) off of ebay and I guess I got lucky because they all consistently tested at 700mAh which is at least usable in my small 1000lm Cree flashlights.

It’s not just the mah that is low, also the current capability.
Saying that these are fine in a 1000lm light is not really true.

I seriously doubt that 1000lm light will be making 1000lm on these cells.

Conservatively assuming your 1000lm light draws 2.5amps (2500mah),
and assuming these cells can actually supply 2.5 amps (maybe, maybe not),
each cell would offer about 17 minutes of runtime on high.
Compare this to 80 minutes for a normal decent cell. Flat Stare

Speed4goal
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Those 700mah cells would fallnflat on there face from their own internal resistance. 2.8-3 amps would kill the cell in 5 mins I believe I hope he has a real Cree 1000lm flashlight and not a eBay/amazon 1000lm flashlight. Every sk98, t6 light on amazon is a “1000” lumen light

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