> John's formula is an attempt to take a parameter (O/C Voltage) that is
known to NOT accurately reflect state of charge, and to use it to
APPROXIMATELY determine state of charge. The result is necessarily
approximate and will vary, possibly widely, with circumstance.

Yep, especially temperature. This approach has the virtue of tending to
reflect reality more accurately the longer the battery sits, corresponding
well with many vehicle applications. But YMMV.

Jack
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist