View Single Post
  #29   Report Post  
Posted to sci.electronics.repair
William Sommerwerck William Sommerwerck is offline
external usenet poster
 
Posts: 3,833
Default the lie of rapid NiMH self-discharge

"Phil Allison" wrote in message
...
"Jeff Liebermann"


NiMH cells do NOT totally discharge themselves. They discharge to
about 50% of capacity (by self-discharge) and then just sit there.


** I have several sets of AA NiMH cells - all Sanyo brand and rated at

1700
to 2500 mAH.


Self discharge is a REAL problem, but no worse than with NiCds.


In general, charged cells lose 90% of capacity in about 6 to 8 weeks -
taking a full 6 hour charge at 400mA to recover.


In my Canon A430, the uncharged cells will run the back display for a few
minutes, let me take a few shots and maybe one flash before the camera

shuts
down.


I wonder if the "spectacular" behavior of my 2700mAh Sanyos has anything to
do with their "superlattice alloy" construction. These appear to be the only
Sanyos using this design. (That's life, I guess.)

http://en.wikipedia.org/wiki/Superlattice

Anyone care to explain this article to me?