Battery information

[elarson]

Hi All,

I'm trying to finish a design that runs on 4 AA batteries. The device has a
small usable voltage range from 6 to 5 volts. I haven't had much luck with
finding information on how to calulate the amp-hour life for that range of
voltage. If anyone knows of a good website, please post.

Thanks

 

[Mac]

On Fri, 22 Apr 2005 19:27:46 -0400, elarson wrote:

Hi All,

I'm trying to finish a design that runs on 4 AA batteries. The device has a
small usable voltage range from 6 to 5 volts. I haven't had much luck with
finding information on how to calulate the amp-hour life for that range of
voltage. If anyone knows of a good website, please post.

Thanks

Go to Duracell's website. They have an "OEM" area:

http://www.duracell.com/oem/productdata/default.asp

The URL for the AA datasheet is:
http://www.duracell.com/oem/Pdf/new/1500_US_CT.pdf

It looks like it takes an AA battery about 3 hours to go from 1.5 V
to 1.25 V when it discharges at 0.25 Amps.

For much lower discharge rates it will likely be much better.

As for Amp Hour ratings, it looks like the quarter-Watt amp-hour rating
(for a single cell) is around 700 mAh for a cutoff Voltage of 1.25. Again,
lower discharge rates will yield higher Amp-hour ratings.

One thing is for sure, though. The batteries still have a lot of energy
left in them when they get to 1.25V!

HTH!

--Mac

 

[elarson]

That was a great help, thanks!

Eric
"Mac" <foo@bar.net> wrote in message
newsan.2005.04.23.01.37.18.825396@bar.net...

On Fri, 22 Apr 2005 19:27:46 -0400, elarson wrote:

Hi All,

I'm trying to finish a design that runs on 4 AA batteries. The device has
a
small usable voltage range from 6 to 5 volts. I haven't had much luck
with
finding information on how to calulate the amp-hour life for that range
of
voltage. If anyone knows of a good website, please post.

Thanks

Go to Duracell's website. They have an "OEM" area:

http://www.duracell.com/oem/productdata/default.asp

The URL for the AA datasheet is:
http://www.duracell.com/oem/Pdf/new/1500_US_CT.pdf

It looks like it takes an AA battery about 3 hours to go from 1.5 V
to 1.25 V when it discharges at 0.25 Amps.

For much lower discharge rates it will likely be much better.

As for Amp Hour ratings, it looks like the quarter-Watt amp-hour rating
(for a single cell) is around 700 mAh for a cutoff Voltage of 1.25. Again,
lower discharge rates will yield higher Amp-hour ratings.

One thing is for sure, though. The batteries still have a lot of energy
left in them when they get to 1.25V!

HTH!

--Mac