Alkaline Battery Capacity

B

Bill Bowden

Guest
Can't seem to locate any battery specs for Alkaline "D" cells. Tried
the Duracell and Raovac sites, but couldn't find much data for
standard cells. Read a few notes indicating the capacity of a standard
"D cell" is somewhere between 12 and 16 amp hours.

Anybody know what capacity to expect from a standard Alkaline "D cell"
at a continuous 0.5mA discharge rate until the voltage falls to 1.1
volts?

Thanks,

-Bill
 
"Bill Bowden" <wrongaddress@att.net> wrote in message
news:36e15247-37e5-46be-97cc-312cdd5ebfcc@26g2000hsk.googlegroups.com...
Can't seem to locate any battery specs for Alkaline "D" cells. Tried
the Duracell and Raovac sites, but couldn't find much data for
standard cells. Read a few notes indicating the capacity of a standard
"D cell" is somewhere between 12 and 16 amp hours.

Anybody know what capacity to expect from a standard Alkaline "D cell"
at a continuous 0.5mA discharge rate until the voltage falls to 1.1
volts?

Thanks,

-Bill
Click to expand...

http://www.duracell.com/oem/Pdf/new/MN1300_US_CT.pdf
 
On Sat, 07 Jun 2008 22:31:26 -0700, Bill Bowden wrote:

Can't seem to locate any battery specs for Alkaline "D" cells. Tried the
Duracell and Raovac sites, but couldn't find much data for standard
cells. Read a few notes indicating the capacity of a standard "D cell"
is somewhere between 12 and 16 amp hours.

Anybody know what capacity to expect from a standard Alkaline "D cell"
at a continuous 0.5mA discharge rate until the voltage falls to 1.1
volts?

Thanks,

-Bill
Click to expand...
If you design things to work all the way down to 0.9V/cell then it'll be
a better fit for NiMHs, and you'll wring a tad more running time out of
your battery.

You may find that at such a low current you're limited by the shelf life
of the battery (you certainly will be for NiMHs!). Unfortunately that
particular data sheet doesn't give it, but alkaline cells seem to last
for years on the shelf, so it may not be that much of a consideration.

--
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com

Need to learn how to apply control theory in your embedded system?
"Applied Control Theory for Embedded Systems" by Tim Wescott
Elsevier/Newnes, http://www.wescottdesign.com/actfes/actfes.html
 
On Sun, 8 Jun 2008 11:48:12 -0700, "BobW"
<nimby_NEEDSPAM@roadrunner.com> wrote:

"Tim Wescott" <tim@seemywebsite.com> wrote in message
news:sMOdnddNudorltHVnZ2dnUVZ_tfinZ2d@web-ster.com...
On Sat, 07 Jun 2008 22:31:26 -0700, Bill Bowden wrote:

Can't seem to locate any battery specs for Alkaline "D" cells. Tried the
Duracell and Raovac sites, but couldn't find much data for standard
cells. Read a few notes indicating the capacity of a standard "D cell"
is somewhere between 12 and 16 amp hours.

Anybody know what capacity to expect from a standard Alkaline "D cell"
at a continuous 0.5mA discharge rate until the voltage falls to 1.1
volts?

Thanks,

-Bill

If you design things to work all the way down to 0.9V/cell then it'll be
a better fit for NiMHs, and you'll wring a tad more running time out of
your battery.

You may find that at such a low current you're limited by the shelf life
of the battery (you certainly will be for NiMHs!). Unfortunately that
particular data sheet doesn't give it, but alkaline cells seem to last
for years on the shelf, so it may not be that much of a consideration.

--
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com


Take a look at the so-called "hybrid" NiMH batteries. They claim MUCH longer
shelf life, and as a side benefit of this, they come pre-charged.

There are a few manufacturers of this new technology. Sanyo (Eneloop brand)
is one of them:

http://www.eneloopusa.com/eneloop.html

http://www.eneloop.info/fileadmin/redakteur/Articles/Teraoka_Article_EN.pdf

Bob
Click to expand...
To name a few I've read about:
Uniross Hybrio
Sanyo Eneloop
Nexcell EnergyOn
Accupower Acculoop

I think they are typically a little less in terms of mAh capacity
(2000 to 2100 versus 2600+ elsewhere, for example.) Also, I remember
reading this:

http://www.amazon.com/review/R1HMYU4BKE0VY7/ref=cm_cr_rdp_perm

Not sure if the poster did their work well, or not. But it is a
cautionary word on the topic of taking the manufacturers' specs on
their face.

If the OP is close on the 12-16 Ah capacity of an alkaline D cell and
that is the range the OP is looking for (or better), then with 500uA
draw we are talking about 3-4 year operation. NiMH seems wrong on
that point.

Jon
 
Jonathan Kirwan wrote:
On Sun, 8 Jun 2008 11:48:12 -0700, "BobW"
nimby_NEEDSPAM@roadrunner.com> wrote:

"Tim Wescott" <tim@seemywebsite.com> wrote in message
news:sMOdnddNudorltHVnZ2dnUVZ_tfinZ2d@web-ster.com...
On Sat, 07 Jun 2008 22:31:26 -0700, Bill Bowden wrote:

Can't seem to locate any battery specs for Alkaline "D" cells. Tried the
Duracell and Raovac sites, but couldn't find much data for standard
cells. Read a few notes indicating the capacity of a standard "D cell"
is somewhere between 12 and 16 amp hours.

Anybody know what capacity to expect from a standard Alkaline "D cell"
at a continuous 0.5mA discharge rate until the voltage falls to 1.1
volts?

Thanks,

-Bill
If you design things to work all the way down to 0.9V/cell then it'll be
a better fit for NiMHs, and you'll wring a tad more running time out of
your battery.

You may find that at such a low current you're limited by the shelf life
of the battery (you certainly will be for NiMHs!). Unfortunately that
particular data sheet doesn't give it, but alkaline cells seem to last
for years on the shelf, so it may not be that much of a consideration.

--
Tim Wescott
Control systems and communications consulting
http://www.wescottdesign.com

Take a look at the so-called "hybrid" NiMH batteries. They claim MUCH longer
shelf life, and as a side benefit of this, they come pre-charged.

There are a few manufacturers of this new technology. Sanyo (Eneloop brand)
is one of them:

http://www.eneloopusa.com/eneloop.html

http://www.eneloop.info/fileadmin/redakteur/Articles/Teraoka_Article_EN.pdf

Bob

To name a few I've read about:
Uniross Hybrio
Sanyo Eneloop
Nexcell EnergyOn
Accupower Acculoop

I think they are typically a little less in terms of mAh capacity
(2000 to 2100 versus 2600+ elsewhere, for example.) Also, I remember
reading this:

http://www.amazon.com/review/R1HMYU4BKE0VY7/ref=cm_cr_rdp_perm

Not sure if the poster did their work well, or not. But it is a
cautionary word on the topic of taking the manufacturers' specs on
their face.

If the OP is close on the 12-16 Ah capacity of an alkaline D cell and
that is the range the OP is looking for (or better), then with 500uA
draw we are talking about 3-4 year operation. NiMH seems wrong on
that point.

Jon
Click to expand...
This post was a poor choice to proselytize given the life requirements,
I just have a 'thing' for folks who design battery-powered systems
assuming 1.2V per cell (or 1.5V per cell) because that's what it says on
the package.

0.9V per cell is about right for moderate discharge rates with NiCd and
NiMH batteries, and you can't exactly harm a primary cell by sucking a
bit more juice out of it.

I _do_ suspect that for many dry cells, you'll get killed by shelf life
(or rust) before the actual circuit drain causes a problem.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html
 
Bill Bowden wrote:

Can't seem to locate any battery specs for Alkaline "D" cells. Tried
the Duracell and Raovac sites, but couldn't find much data for
standard cells. Read a few notes indicating the capacity of a standard
"D cell" is somewhere between 12 and 16 amp hours.

Anybody know what capacity to expect from a standard Alkaline "D cell"
at a continuous 0.5mA discharge rate until the voltage falls to 1.1
volts?
Click to expand...
Off the top of my head it was between 2 and 3 Ah.

You'll get better out of other brands than Duracell though.

Graham
 
On Jun 9, 1:28 pm, d...@manx.misty.com (Don Klipstein) wrote:
In <1tidnQB1A7Qc2NHVnZ2dnUVZ_uOdn...@web-ster.com>, Tim Wescott wrote:



Jonathan Kirwan wrote:

To name a few I've read about:
Uniross Hybrio
Sanyo Eneloop
Nexcell EnergyOn
Accupower Acculoop

I think they are typically a little less in terms of mAh capacity
(2000 to 2100 versus 2600+ elsewhere, for example.) Also, I remember
reading this:

http://www.amazon.com/review/R1HMYU4BKE0VY7/ref=cm_cr_rdp_perm

Not sure if the poster did their work well, or not. But it is a
cautionary word on the topic of taking the manufacturers' specs on
their face.

If the OP is close on the 12-16 Ah capacity of an alkaline D cell and
that is the range the OP is looking for (or better), then with 500uA
draw we are talking about 3-4 year operation. NiMH seems wrong on
that point.

Jon

This post was a poor choice to proselytize given the life requirements,
I just have a 'thing' for folks who design battery-powered systems
assuming 1.2V per cell (or 1.5V per cell) because that's what it says on
the package.

0.9V per cell is about right for moderate discharge rates with NiCd and
NiMH batteries, and you can't exactly harm a primary cell by sucking a
bit more juice out of it.

I _do_ suspect that for many dry cells, you'll get killed by shelf life
(or rust) before the actual circuit drain causes a problem.

My experience with NiMH is that 1.2 volts per cell is conservative at
C/5 discharge rate and 80% of the way discharged. My experience is that
NiMH mostly achieves at least 1.25 volts/cell at that discharge rate.

- Don Klipstein (d...@misty.com)
Click to expand...

In what time frame? I need 2 to 3 year continuous operating time and
not sure that's doable with a NiMH battery due to the high self
discharge rate.

-Bill
 
Bill Bowden wrote:
On Jun 9, 1:28 pm, d...@manx.misty.com (Don Klipstein) wrote:
In <1tidnQB1A7Qc2NHVnZ2dnUVZ_uOdn...@web-ster.com>, Tim Wescott wrote:



Jonathan Kirwan wrote:
To name a few I've read about:
Uniross Hybrio
Sanyo Eneloop
Nexcell EnergyOn
Accupower Acculoop
I think they are typically a little less in terms of mAh capacity
(2000 to 2100 versus 2600+ elsewhere, for example.) Also, I remember
reading this:
http://www.amazon.com/review/R1HMYU4BKE0VY7/ref=cm_cr_rdp_perm
Not sure if the poster did their work well, or not. But it is a
cautionary word on the topic of taking the manufacturers' specs on
their face.
If the OP is close on the 12-16 Ah capacity of an alkaline D cell and
that is the range the OP is looking for (or better), then with 500uA
draw we are talking about 3-4 year operation. NiMH seems wrong on
that point.
Jon
This post was a poor choice to proselytize given the life requirements,
I just have a 'thing' for folks who design battery-powered systems
assuming 1.2V per cell (or 1.5V per cell) because that's what it says on
the package.
0.9V per cell is about right for moderate discharge rates with NiCd and
NiMH batteries, and you can't exactly harm a primary cell by sucking a
bit more juice out of it.
I _do_ suspect that for many dry cells, you'll get killed by shelf life
(or rust) before the actual circuit drain causes a problem.
My experience with NiMH is that 1.2 volts per cell is conservative at
C/5 discharge rate and 80% of the way discharged. My experience is that
NiMH mostly achieves at least 1.25 volts/cell at that discharge rate.

- Don Klipstein (d...@misty.com)


In what time frame? I need 2 to 3 year continuous operating time and
not sure that's doable with a NiMH battery due to the high self
discharge rate.

-Bill
Click to expand...
Use alkalines. And forgive me for the tangent; it seems to be drawing
more interest than your original post (other than designing for 0.9V per
cell, if you can -- it should gain you a month or two of operating time
at the end of the battery life curve).

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" gives you just what it says.
See details at http://www.wescottdesign.com/actfes/actfes.html
 
On Tue, 10 Jun 2008 04:14:01 +0000 (UTC), don@manx.misty.com (Don
Klipstein) wrote:

In <1150157d-d87b-4be7-b59f-b1a5298e5849@a1g2000hsb.googlegroups.com>,
Bill Bowden wrote:

In what time frame? I need 2 to 3 year continuous operating time and
not sure that's doable with a NiMH battery due to the high self
discharge rate.

NiMH ain't gonna do that. Use alkaline. I was only commenting on what
voltage NiMH delivers.

- Don Klipstein (don@misty.com)
Click to expand...
I just checked the Energizer curve for their alkaline D cell (E-95)
and they include a chart that shows a service life at a 2mA discharge
(4X the OP's spec) that is 4000 hours down to 1.2V or something around
6500 hours down to 1.0V. The curve is roughly linear in the 2mA to
1mA span, and shows about 8000 hours down to 1.2V at 1mA, so
extrapolating backwards it works out to 16k hours to 1.2V and 26k
hours down to 1.0V. This is squarely in the 2-3 year range. If the
op can accept operation down to 1.2V, then almost 2 years. If down to
1.0V, then almost 3 years.

Assuming the environmental characteristics required are consistent
with the specs, anyway, and that extrapolation backwards into 500uA
territory isn't too optimistic. I gather from cursory reading that
shelf lives are in the 5-7 year category, with an 80% of rated
capacity remaining, and assuming a constant 70F temp. If that
represents a rough guide for consideration, then D cell self-discharge
is somewhere in the neighborhood of 40-50uA. (The mid-span within a
larger span given from a rated capacity at 1.0V or 1.2V and 5 years or
7 years as the shelf life to 80%.) That is enough below 500uA to
suggest that extrapolation isn't unreasonable.

I may be missing something important, though.

Jon
 
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