Battery weight

[Joe Mayers]

I have bought good and fake 18650 batteries. They seem to weigh differently.

I have what I think is a fake Ultrafire 3800 mah battery and it weighs 31 grams - it is new and has no capacity
I have what I believe is a genuine Sanyo 2200 mah battery and it weighs 45 grams - 50% more weight with 2/3's the mah rating - It will run a T6 for hours on high

Does this seem reasonable as a way to detect junk batteries.

I have seen the following quote on a few sites, any idea if this is true?

"As of July 2013, the highest capacity 18650 cell is the Panasonic NCR18650B, 3400mAh at a minimum cost of $10/cell"

If so, anything with 3800 mah on it is a fake?

Thanks, Joe Mayers

 

[mattheww50]

Don't know if I would use the word fake, but clearly any 18650 that claims a capacity in excess of 3400 mAh is not being accurately described, and odds the capacity is less than claimed, usually
a LOT less....