>    A battery that only reads 12v is junk. If it doesn't read a minimum 
>of 12.5, forget it, IMHO. Actually, most battery texts agree, that I've 
>ever seen. And having lived off grid for about 17 years of my life, 
>using, maintaining, and even repairing batterys , I've read every thing I 
>could find about batterys and how they function. And contrary to what was 
>posted here earlier, a "good" battery stays at 13.5 and not just after 
>it's charged briefly. Under load it might go lower, butshould spring 
>right back after the load is taken back off. 

A good battery will not stay at 13.5 after the surface charge has been 
removed from the battery. It will max out around 12.6 unless it has been 
run all the way down
at some point, after which it will max out at 12.5. Readings above 12.6 are 
sort of false surface charge readings and should be disregarded. If you get a

reading above 12.6 put a load on the system for a while (such as running 
headlights) and then retest it. You will probably show 12.5 or 12.6.

The idea that a battery will stay at 13.5 volts is silly.

--Is this note sufficiently provocative?