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aladinlamp
02-27-2008, 04:44 PM
Is there any equation to calculate how many watthours are needed to move charging battery from-to certain voltage

example

how many watthours to move 12V 7,2 AH lead acid battery from 12.00V to 12.50V

thanx

theremart
03-02-2008, 04:09 AM
Is there any equation to calculate how many watthours are needed to move charging battery from-to certain voltage

example

how many watthours to move 12V 7,2 AH lead acid battery from 12.00V to 12.50V

thanx

That is an interesting thought..

The problem is varibles..


A - Amount of sulfation on the plates.
B - Temperature of room batteries are in.
C - Efficiently of the circuit charging them.
D - The ph level in each cell of the battery
E - How good are the connection of the wires to batteries.
F - Has the battery been abused or is damaged, Heat damage, or broken plates etc..


Any of these can be a factor, and more..

Granz
03-03-2008, 11:16 PM
I'm also interested in this kind of information. There are many people who have replicated Bedini results but it's tough to find solid performance values in one place.

How many "effective amps" are output in a basic setup? If I can charge a 24V battery in 24hours and from that battery operate a 1A load for an hour before discharge, then I have an effective 1A output. Can this be repeated dozens of times without unusual battery degradation?

How large would a 1A output system be and how heavy would it be? What about a solid state version? Can this be scaled up to a 10A output, 100A output, 1000A output? What about physical dimensions and weight for larger output?

ren
03-04-2008, 09:30 PM
Granz, your question/statement has me a little confused as to how to answer. Mainly I dont understand what you are asking. I think you may not understand the principles.

With lead acids the best way to run a load is to stay within c/20 discharge rates and use the least amount. By that I mean under normal charging conditions a battery will last significantly more cycles if only discharged 20%. Usually you wouldnt take it lower than half full. The SG could change that though...

If you wanted to run a 1 amp load then you would need to discharge a 20 amp hour battery @ 1 amp over 20 hours. You would stop at 10 hours for your battery to be 50% full.

I have some little 1.3ah's that I have been charging with the sg and after 10 hours they are resting @ 12.70v, which is at least 70% full.

Granz
03-05-2008, 03:37 AM
"I have some little 1.3ah's that I have been charging with the sg and after 10 hours they are resting @ 12.70v, which is at least 70% full."

Ok so using your situation, you're assuming that a voltage indication is an energy storage indication which is not something that I would be comfortable with while charging on SG. In other words, the discharge curve is no longer reliable and should be confirmed since you're charging with a non-standard unit.

If you calculate how many Watts you actually get out of your little 1.3Ah's and how long it took to charge up to that level, then repeat 10 or 20 times, you'll confirm or deny SG charging characteristics. Once reliable data is recorded, you can give a figure for the actual output of the SG.
If you find that your batteries are deteriorating more rapidly than they should be, then you can assume that the SG is not charging well and is in fact not reliable.

On the other hand, if you can confirm that the charging is reliable and you can get an accurate output rate, then you can theorize output on larger SG units and answer some of the other (more important) questions I had asked.

Granz
03-05-2008, 04:00 AM
Can't edit for some reason.....but what I meant to say was calculate how many Watt *hours* you get, not just Watts.

ren
03-05-2008, 07:19 AM
I understand what your saying and although I never did math cop testing I did enough cop cycles to see that the battery was charging better and holding its charge better.

A voltage if measured when the battery has rested is a fairly reliable means to test the capacity of the battery. You could experience errors if the battery was damaged but load tests would tell you of that anyway.

Granz
03-05-2008, 02:43 PM
OK so you're confident that charging is reliable.

Why no attempt to calculate an output value? That way you can determine how effective the unit is for its size. Then theorize on output values for larger units. Perhaps theorize output on a unit that's three times the size of your current unit, and then see if the theory is proven in the real world.

Then you can calculate requirements for a real performer cranking out an effective 1000A.

It seems to me like this is quite an extraordinary find and if it works as indicated it deserves full investigation into potential for more than AA battery charging.