View Single Post
Old 01-24-2012, 11:19 PM   #27
_cy_ OP
Beastly Adventurer
Joined: Sep 2011
Location: Tulsa, Oklahoma
Oddometer: 5,875
Originally Posted by herrhelmet View Post
Lithium Iron Phosphate batteries DO NOT discharge at 5-10% per month. Real world experience here. Less than 1% per month static use.
that's been my experience as well... 1-2% per month for (bare, non-protected) li-ion cells I've personally used. Note the 5-10% figure was for smart circuits. protected li-ion cells drains ranged from almost no drain to rates comparable to wet lead acid.

herein lies the problem of data all over the place.

very proud to say that I was part of the small group of initial adopters on Candlepower forums. we were among the world first users of individual li-ion cells. as in up close and personal ... in bleeding edge flashlights.

the world's first protected li-ion cell was conceived on Candlepower forums. pioneered by JS Burley, who mortaged his house to finance those first R123 protected cells. delays after delays... I was part of the original group buy for those cells. finally the Chinese factory finally did deliver ... they barely performed with a miserable 150 milliamp capacity.

what happened next repeated itself many times ... the Chinese then took the technology paid for by JS Burley and proceeded to develop the li-ion technology into the mature li-ion cells in common use today. JS Burley ended up losing his shirt over developing world's first protected R123 cells.

most of the dangers occurred during the charging process. back then I used a Triton and Shulze charger. unlike lithium iron phosphate's very stable chemistry. early li-ion cells had entirely different characteristics.

along with li-ion's desirable characteristics ... danger of li-ion happened during charging. li-ion cells will take a charge long as voltage is delivered... until thermal runaway (explosion) occurs some where about 4.9v. unlike lithium iron phosphate. lithium cobalt operating range is 4.2v fully charged.... 3.5v discharged. very little residual current remains to 3v where permanent damage occurs to cell.

many advances since those early days....

_cy_ screwed with this post 01-28-2012 at 10:29 AM
_cy_ is online now   Reply With Quote