Does the size of the battery relate to storage capacity?

[rodfran]

If I had a D cell rated at a true 4500 mah and a C cell rated at a true 5000 mah, would the C cell have more capacity even though the D cell is a larger battery?

 

[ekincam]

Possibly. I've been warned some manufacturers over rate their cells and some use C cells in D size containers.

 

[Marduke]

Yes, more mAh = more capacity

 

[Mr Happy]

Let's try a similar kind of question:

If I had a marble that weighed 1 oz, and a balloon that weighed 1/10 oz, would the marble be heavier than the balloon even though the balloon is much bigger?

 

[Lightguy27]

Well, assuming that the Batts had true un-biast mAH ratings than yes.

 

[Illum]

dulridge, I demand pics of these ex-sub cells!

 

[65535]

Mass is generally the preferred unit, such as KW/Kg or W/g

 

[hopkins]

consider a lithium AA cell and a 'heavy duty' AA cell.
The lithium has maybe 4 times the power than the heavy duty chemistry.
And the lithium weighs about 40% less. Who knows why?

And of course the extreme example of atomic power !

So less can mean a lot more (or not). Variables galore.
Only the CPF guru's can reveal the mystery.

 

[VidPro]

the capacity is the capacity, a 4500ma capacity is less than a 5000ma capacity, no mater the package size.
although
If its in a larger package (D vrses C) and of similar capacity, then chances are it might be more "robust"
in other words i would rather have a Ni-Cad cell of D size and 4500ma , than a High cap C cell ni-mhy of 4500ma, because it might cope with more issues. or say a new tech LSD D-cell of lesser capacity than a high-cap C cell of normal ni-mhy.

soo i would never (well almost never) waste the space of a D-cell location with a C-cell of even greater capacity, because the more materials in the D-cell could be materials that make it more robust, and long lasting. if you have the SPACE and can handle the weight of the larger cell, and everything else is the same (including cell quality) then use the D-cell.

this of course discludes stupid "sleeved" batteries that have no more battery materials, and are just plastic spacers.

 

[Nubo]

If I had a D cell rated at a true 4500 mah and a C cell rated at a true 5000 mah, would the C cell have more capacity even though the D cell is a larger battery?

Your example implies that you might be comparing a D-size NiCD battery with a C-size NiMH battery. Since the mah capacities are fairly close, a better question might be "which battery is better suited to my application"? Each type has a different set of advantages and disadvantages. Mah is only part of the story.

 

[Marduke]

Let us not forget also that Energizer has a bad habit of sticking their 2500mAh AA's into a D-cell shell, and selling it as a D-size rechargeable. Absolutely no benefit of using this setup over even the cheap DX 2xAA to D parallel converters, as the Energizer D cell is little more than a very fat AA cell.

 

[TorchBoy]

Mass is generally the preferred unit, such as KW/KG or W/G

It's preferable to use the correct symbols, too. In the above case I presume you mean "kW/kg or W/g".

 

[jasonsmaglites]

Let us not forget also that Energizer has a bad habit of sticking their 2500mAh AA's into a D-cell shell, and selling it as a D-size rechargeable. Absolutely no benefit of using this setup over even the cheap DX 2xAA to D parallel converters, as the Energizer D cell is little more than a very fat AA cell.

yes i hate that!
also radio shack will rip you off with some 4500mah d cell nimh.
search for some d cell 10000mah from tenergy or also maha makes some nice ones too i think.

d cells of similiar value, will have twice the capacity of c cells.
good d cell =10000mah to 12000mah
good c cell = 5000to 6000mah

 

[65535]

It's preferable to use the correct symbols, too. In the above case I presume you mean "kW/kg or W/g".

He he...

That or the less common KW/cm^3, which is usually considered energy density, how much capacity can be crammed into the smallest size cell.

Depending on you application one over the other is useful. per volume is a good way to compare different chemistries, but mass is usually more useful when weight comes in as a factor in the required capacity.

 

[lctorana]

And don't forget the supermarket D NiCads of 1400mAh capacity (which, after reading the fine print, you find even that is an exaggeration. They are 1200mAh.)

Perversely, I have three of these which give very good service.

But they weigh like a feather, and when you think you can get a 5000mAh Nicad, or a 10000mAh NiMH in the same package, it is just annoying.

 

[Mr Happy]

KW/cm^3

kW/cm^3

I think you are just doing it deliberately...

 

[TorchBoy]

I was going to say that kelvin-watts per cubic centimeter are very uncommon. Can't say I've ever used them myself. :shakehead (Yes, that capitalisation really does mean something different.)

My father still has some NiCd C and D cells that are (or were) 1200mAh. They were probably horrendously expensive to buy, but now I'd rather just use an Eneloop in an adaptor.

 

[Nubo]

kW/cm^3

I think you are just doing it deliberately...

Well, could come in handy some day. The folks who designed the Mars Polar Orbiter could have used a bit more poking about units.

 

[TorchBoy]

Well, could come in handy some day. The folks who designed the Mars Polar Orbiter could have used a bit more poking about units.

"D'oh! " Seriously, using imperial for spaceflight?!?

 

[rizky_p]

Well by using the same chemistry bigger dimension usually related to higher Capacity as long as the manufacturers are sincere with their rating and using the same methods. And the way electrodes are folded will also corelate to its capacity and discharge capacity.