I've been on this particular soap box before....
I've purchased and tested every 18650 holder I could buy though "normal
distribution" (Mouser, Digikey, Allied, etc) I have a box around here
somewhere with the wreckage of at least 20 versions.
After testing I've come to a simple conclusion - I will _not_ put any of
them in my production products.

Each have their own issues, but the one I seen over and over again is that
the housing grips the cells so tight that the spring tabs cannot move the
cell. The resulting failure is that a little bump or hit can slide the cell
away from one end and break contact, since the compressed contact cannot
overcome the holder's friction, the product remains dead.

I'm currently planning to tab weld the cells (more likely have a supplier
do it) and debating soldering the tabs directly to the PCB, or a pigtail+
wire to board connector.

-Denny
--=20
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