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"krj" wrote in message . ..
Capt. NealŪ wrote:
"krj" wrote in message . ..
Capt. NealŪ wrote:
"krj" wrote in message . ..
Capt. NealŪ wrote:
"Meindert Sprang" wrote in message ...
"Capt. NealŪ" wrote in message
...
I'm talking about two 12v batteries in a series circuit meaning one
positive pole connected
to the negative pole of the other battery. The left over positive and
negative poles must be
connected to some sort of circuit and load such as a light bulb or
electronic gadget that will
cause current to flow through the entire circuit.
In such a circuit, neither battery will charge the other, they will only be
discharged together through the load.
The same current will flow through both batteries, and in both batteries you
can regard the current as "flowing out" of the positive pole.
To charge a battery, current must be flowing "into" the positive pole, which
can only happen if you connect two batteries in parallel, where one is more
discharged than the other.
Meindert
You are wrong. You cannot run current though a battery backwards. You charge with a charging
source that has higher voltage than the battery and by wiring it so there exists a complete
circuit.
When I connect my photovoltaic to my 12v battery the battery takes a charge because the
photovoltaics operate at 16v at ten amps current. The 16v, being higher than the 12v in the
batteries causes a chemical reaction to occur between the sponge lead and the solid lead
and the acid electrolyte and electrons are stored The chemical reaction reverses when the
photovoltaics are removed and a load placed upon the batteries and electrons are released.
Current never goes backwards in the battery.
This is a common misconception and I'm very surprised so-called engineers fall prey to it.
CN
Let's see, +16v from the solar panel to the +12.7v on the battery. - from the solar panel connected to - on the battery. 10
amps or current is flowing. Which way through the battery is the current? If the current is not flowing through the battery,
where is it going?
krj
Duh, Current NEVER flows through the battery. A battery stores and releases electricity
chemically. There is no circuit passing through the battery. The only circuit that exists is
external to the battery. View a battery as a gasoline tank gas (electrons) can be added
to the tank or removed from the tank. It's a storage device and not a pipe of some sort
that has flow one way or the other inside it.
http://hyperphysics.phy-astr.gsu.edu.../leadacid.html
Note how current flow is only shown to be reversed in the circuit outside the
battery when charged. Never, at any time is there any such corresponding flow
or circuitry inside the battery. There is but a series of plates and an electrolyte
that stores or releases electrons. A battery is a tank and only a tank. It is not
a circuit.
CN
So, where is the 10 amps going? Are you saying there is no current flow? If I put an ampmeter is series with the line will it
read 10 amps?
How do batteries work?
The current is running chemical reactions that are housed inside the battery.
Electrons are being stored by these chemical reactions. When the battery is
fully charged (chemical reaction have run their course) then no more electrons
can be stored. If you continue to cram current in it begins to drive another
chemical reaction - it electrolyses the water into hydrogen and ozygen.
View a lead/acid battery as a condensor of sorts. A condensor can take and
hold a charge but there in no circuit inside the thing. Take one apart and you'll
find a long piece of aluminum foil rolled up with a long piece of wax paper. Electrons
go in and are stored. To let them back out just short the center to the outer casing
and "pow" there they go . . .
A lead/acid battery stores electrons (storage battery - get it?) via chemical means
not physical means like a condensor.
Electricity, as you probably already know, is the flow of electrons through a conductive path like a wire. This path is called a
circuit.
Batteries have three parts, an anode (-), a cathode (+), and the electrolyte. The cathode and anode (the positive and negative
sides at either end of a traditional battery) are hooked up to an electrical circuit.
The chemical reactions in the battery causes a build up of electrons at the anode. This results in an electrical difference
between the anode and the cathode. You can think of this difference as an unstable build-up of the electrons. The electrons
wants to rearrange themselves to get rid of this difference. But they do this in a certain way. Electrons repel each other and
try to go to a place with fewer electrons.
If there was a circuit inside, don't you think it would discharge, or worse yet,
never charge to begin with? It doesn't discharge because it can't - there
is no circuit inside the battery.
You never heard of "self discharge" of a lead acid battery?
In a battery, the only place to go is to the cathode. But, the electrolyte keeps the electrons from going straight from the
anode to the cathode within the battery. When the circuit is closed (a wire connects the cathode and the anode) the electrons
will be able to get to the cathode. In the picture above, the electrons go through the wire, lighting the light bulb along the
way. This is one way of describing how electrical potential causes electrons to flow through the circuit.
However, these electrochemical processes change the chemicals in anode and cathode to make them stop supplying electrons. So
there is a limited amount of power available in a battery.
When you recharge a battery, you change the direction of the flow of electrons using another power source, such as solar panels.
The electrochemical processes happen in reverse, and the anode and cathode are restored to their original state and can again
provide full power.
You don't change the flow of electrons inside the battery because no
circuit exists there to do so. You just add them to the tank.
CN
Too stupid for comments!
Or, too correct for valid rebuttal . . .
CN
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