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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
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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!
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