At 10:46 PM 11/20/97 -0500, you wrote:
>    I know this is one of the most of basic questions for the experienced
>out there, but I don't know it and I thought this would be a good quick way
>to find the answer. I'm developing a few battery based applications and was
>wondering on ratings. Am I correct in assuming that the standard rating is
>Amp/Hours? And if so, is it just a ratio, i.e. a 1 amp/hour battery could
>theoretically supply 2 amps for 30 minutes? And lastly, does anyone have a
>chart on the amp/hour ratings on most popular battery types, AA, AAA, 9V,
>Alkaline, Normal, Ni-Cad? Thanks in advance for any into. TTYL
>
>
BATTERY LIFE    Load in mA
-----Type------ 0.8  8.0  80
"AA" Standard   1100 97   4
"AA" Heavy Duty 1350 120  9
"AA" Alkaline   2000 190  16
"C"  Standard   2400 240  12
"C"  Heavy Duty 3650 352  28
"C"  Alkaline   5600 560  49
"C"  Lithium    6250 625  63
"D"  Standard   5600 560  21
"D"  Heavy Duty 7020 702  68
"D"  Alkaline  11500 1200 108
                 Life in hr

The idea is a battery will give 1 amp for 1 hour .5 amp for 2 hour etc.
There are some factors that mess up the ideal world. At high drain the
internal resistance causes the battery to heat up and you lose capacity. At
very low drain there is a self discharge that causes a shelf life and
messes up the results there as well. There are a lot of other factors like
temperature but the general rule of thumb is as above. The chart is typical
values and the best most accurate values would be from the manufacturer of
the batteries themselves due to changes in chemistries and cell design over
time and from company to company.


Larry G. Nelson Sr.
mailto:L.Nelson@ieee.org
http://www.ultranet.com/~nr