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Anonymous Poster

Whats the unit of specific gravity in batteries??

04/01/2010 5:50 AM

Whats the unit of specific gravity in batteries??
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user-deleted-1105
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#1

Re: Whats the unit of specific gravity in batteries??

04/01/2010 7:02 AM

Maybe I'm wrong but isn't specific gravity dimensionless?
It's the density relative to that of water...or maybe I'm mistaken, it's not my field, it's a long time since I did any of that stuff, I'm a cat and it's April 1st.
Yeah, maybe wait for a hooman to answer...
Del

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TVP45
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#2
In reply to #1

Re: Whats the unit of specific gravity in batteries??

04/01/2010 7:32 AM

Wait a minute! Isn't Harlow on the other side of the Prime Meridian? Isn't it the 2nd there? Or March 31st? Or something.

Anyway, you're right (and a GA). No units at all. It's the ratio of mass densities so it all cancels out.

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#6
In reply to #2

Re: Whats the unit of specific gravity in batteries??

04/01/2010 10:35 AM

0.0996 West, when I drive East a mile or so there's this BIG hump in the road where the seam in the Earth's crust is stitched up.
Del

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TVP45
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#7
In reply to #6

Re: Whats the unit of specific gravity in batteries??

04/01/2010 11:10 AM

We have that too, but we thought it was just the freeze-thaw cycle on the asphalt.

http://www.youtube.com/watch?v=gi7FICy0BMs

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charlie_r
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#3

Re: Whats the unit of specific gravity in batteries??

04/01/2010 7:40 AM

If the OP is expecting numbers, your typical lead acid battery at full charge electrolyte shows a specific gravity of 1.250 as compared to distilled water.

Del & TVP45 are correct, it is nothing more than a ratio.

GA to both of them.

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ozzb
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#4
In reply to #3

Re: Whats the unit of specific gravity in batteries??

04/01/2010 8:37 AM

On industrial batteries though the manufacture will increase that to obtain a higher AH rating on the same battery.

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#5

Re: Whats the unit of specific gravity in batteries??

04/01/2010 10:07 AM

Maybe I'm deciphering your Q differently, but could this be what you're after?

Power density (specific power): Power density is the ratio of the power available from a battery to its volume (watt/liter). Specific power generally refers to the ratio of power to mass (watt/kg). Comparison of power to cell mass is more common.

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jhonson
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#8

Re: Whats the unit of specific gravity in batteries??

04/01/2010 3:00 PM

dimensionless unit
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PWSlack
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#9

Re: Whats the unit of specific gravity in batteries??

04/06/2010 3:14 AM

Specific gravity is dimensionless. It is a ratio relative to the density of water.

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