On Thu, 14 Feb 2019 10:48:54 -0800 (PST), "
wrote:

About the only sure method I have found to determine what is counterfeit
and what is real, other than by very close examination of the 'fit and
finish' is the weight.

Real batteries are typically significantly heavier than the fakes, even
discernible between two AAA types. And if you have a 4, 6 or 10 pack
to compare, it is even more obvious.

Yeah, that worked for a while with LiIon 18650 cells.
https://www.instructables.com/id/How-to-know-a-fake-18650-battery/
Then, I started getting cells that all weighed about 65 grams, which
is rather high for an 18650. So, I cut one apart and found that it
was topped off with sand and some hot melt glue to hold the sand in
place. Foiled again.

You would also find out when you send that damaged piece of equipment
back to Duracell or Eveready and have them inform you whether the
batteries are real or not.

In this case, the friend that sent me the photos had already thrown
out the 9V battery. It didn't explode inside any equipment. I blew
up on his incredibly messy desk/workbench when the exposed terminals
were shorted by something conductive. If I had possession of the
remains, I would have doing my own autopsy on the battery, instead of
sending it to the manufacturer.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558