Idea for cell, maybe...

[fisher]

You have to know a bit about electronics in order to understand what Im about to say, but...

What if you made 10 or 12 separate cells, each consisting of only two plates, each wired +-, each in separate housings so that they worked independently of each other. BUT, wire them in series. So that voltage goes into one plate of the first cell, then the wire from the other plate goes to the next cell, and so on.

This would be equavilent to wiring a cell with several neutral plates, each (if there were 10) would get about 1.4 volts each, (with 14 volts applied.)

Now, why have separate cells? As a cell heats up, it's resistance decreases. If you understand series circuits, you know that less resistance, gets less voltage. So assuming that all cells are equal, each cell of ten with 14 volts applied would get 1.4 volts. But as one particular cell began to heat up, it's resistance would decline, consequently it's voltage would decline, causing more voltage to be applied to the colder cells, warming them faster. The hotter cell would get less voltage, enabling it to cool somewhat.

That is the theory, what do you think? Actually, my idea is to have all cells tied together at the bottom so that I don't have to fill each separately, and the air lines exiting the top would connect them together there, but each should pretty much retain it's own water during operation, allowing temperature fuluctuations to cause voltage fluctuations, regulating temperature somewhat. (I hope.)

[Riddler250]

Now, why have separate cells? As a cell heats up, it's resistance decreases.

Isnt it the other way around? resistance=heat and heat = resistance? A 16ga wire with a load of 20a would get hotter than 12ga wire with the same load

[resago]

yeah, the series is the optimum way to go, but takes up about twice the space.

[fisher]

Riddler, we are talking about two different things here. For a wire, bigger wire can handle more current without heating.

But for cells, as a cell heats, it's current increases, which tells me that it's resistance decreased. Think of water flowing through a pipe with a valve. Open the valve wide open, maximum current (flow) due to low restriction (resistance) in the pipe. Close the valve halfway, reduced current due to higher resistance to water flow through the valve.

A bigger wire is a bigger pipe. More current can flow. That is why bigger wire can handle more current.

Resistance does not equal heat. Current equals heat in that more current (in a cell or in a wire) creates more heat. More resistance decreases current, reducing heat.

Clear as mud.

BTW, Im a college electronics instructor. I have splained this before (or at least tried to) on numerous occasions.

[Riddler250]

Riddler, we are talking about two different things here. For a wire, bigger wire can handle more current without heating.

But for cells, as a cell heats, it's current increases, which tells me that it's resistance decreased. Think of water flowing through a pipe with a valve. Open the valve wide open, maximum current (flow) due to low restriction (resistance) in the pipe. Close the valve halfway, reduced current due to higher resistance to water flow through the valve.

A bigger wire is a bigger pipe. More current can flow. That is why bigger wire can handle more current.

Resistance does not equal heat. Current equals heat in that more current (in a cell or in a wire) creates more heat. More resistance decreases current, reducing heat.

Clear as mud.

BTW, Im a college electronics instructor. I have splained this before (or at least tried to) on numerous occasions.
I mean no disrespect but what about joule's law, that states H (Heat) = I2 (Current squared) x R (Resistance) x T (Time the current is allowed to flow).

[fisher]

My best answer is to show you an example.
Heat = I^2*R*T

So lets say we run a generator at 12 volts, for one hour, and it has 4 ohms of resistance. The current will be 3 amps for this circuit. (If you know electronics I (current) = V (voltage) divided by R (resistance).
So a 12 volt power supply with 4 ohms of resistance would pull 3 amps because 12 volts divided by 4 ohms = 3 amps.

Heat = 3 amps ^2 * 4 ohms * 1 hour.
Heat = 9 * 4 * 1
Heat = 36 Joules.

Now, lets decrease the resistance to only 2 ohms, half of the previous value.
Using Ohm's law, the current in the circuit must be 6 amps.
12 volts divided by 2 ohms = 6 amps.

Now lets calculate the heat for the same voltage and time, but at half resistance of the original value, (which gives double current of the original value).

Heat = I^2 * R * T
Heat = 6 amps ^2 * 2 ohms * 1 hour.
Heat = 36 * 2 * 1
Heat = 72 Joules

So doubling the current (halving the resistance) doubled the heat generated.

I am not sure if I made the point but I am enjoying the discussion so let me know.

[Riddler250]

My best answer is to show you an example.
Heat = I^2*R*T

So lets say we run a generator at 12 volts, for one hour, and it has 4 ohms of resistance. The current will be 3 amps for this circuit. (If you know electronics I (current) = V (voltage) divided by R (resistance).
So a 12 volt power supply with 4 ohms of resistance would pull 3 amps because 12 volts divided by 4 ohms = 3 amps.

Heat = 3 amps ^2 * 4 ohms * 1 hour.
Heat = 9 * 4 * 1
Heat = 36 Joules.

Now, lets decrease the resistance to only 2 ohms, half of the previous value.
Using Ohm's law, the current in the circuit must be 6 amps.
12 volts divided by 2 ohms = 6 amps.

Now lets calculate the heat for the same voltage and time, but at half resistance of the original value, (which gives double current of the original value).

Heat = I^2 * R * T
Heat = 6 amps ^2 * 2 ohms * 1 hour.
Heat = 36 * 2 * 1
Heat = 72 Joules

So doubling the current (halving the resistance) doubled the heat generated.

I am not sure if I made the point but I am enjoying the discussion so let me know.

I am thinking in terms of most conductors used in electronics with a positive temperature coefficient. For what you to say to be corect, then stainless would have a negative temperature coefficient (increasing heat lowers resistance). Ive actually only been a tech for a few years, so there is still a lot to learn, but im pretty confident in what i know. After scooterdog its nice to have a professional discussion.:)

[Riddler250]

Riddler, we are talking about two different things here. For a wire, bigger wire can handle more current without heating.

But for cells, as a cell heats, it's current increases, which tells me that it's resistance decreased. Think of water flowing through a pipe with a valve. Open the valve wide open, maximum current (flow) due to low restriction (resistance) in the pipe. Close the valve halfway, reduced current due to higher resistance to water flow through the valve. .

I havnt built a cell yet, so I havnt witnessed it reaction to heat or resistance.

[BoyntonStu]

I havnt built a cell yet, so I havnt witnessed it reaction to heat or resistance.


As the cell temperature rises, the electrolyte resistance lowers.

That is the reason for cell runaway and the necessity for PWM.

BoyntonStu

[Riddler250]

Ive seen a lot about the pwm, but for some reason always skip over it in the posts. But i am on this forum to learn about hho from those who know. I actually have a smacks booster built but havnt powered it up yet, as soon as i built it, i read smiths and painless's threads and decided to go a different route, maybe i can get it started this week, and see first hand how these operate.

[fisher]

My opinion that the resistance of a cell decreases as temperature increases is based on the fact that as the cell is powered on cold, there will be a smaller amount of current than there is after the cell has been on a while and gotten warm. I am sure that you have encountered the vicious cycle of a cell heating, drawing more current, more current makes it get hotter, which makes it draw more current, which makes it hotter...

I conclude from that fact alone, that resistance is decreasing as the cell warms. How else would current be able to increase?

I ran a cell today that began at 12 amps and as it ran, the current grew to 20 amps, and I shut it down because it was getting too hot. It is certain that current increases with heat. I don't know what resistance would be doing other than what Ohm's law would reveal and that is that as current is increasing, with a constant applied voltage, resistance must be decreasing. I don't think it is the temperature coefficient of the stainless, but of the electrolyte.

[fisher]

PWM is my next series of studies, but first I am wanting to exhaust mechanical or physical cell designs that help to counteract the heating problem. I figure that with a combination of a good cell, and a PWM, I can RULE THE WORLD, or at least one little facet of my world.

[Riddler250]

My opinion that the resistance of a cell decreases as temperature increases is based on the fact that as the cell is powered on cold, there will be a smaller amount of current than there is after the cell has been on a while and gotten warm. I am sure that you have encountered the vicious cycle of a cell heating, drawing more current, more current makes it get hotter, which makes it draw more current, which makes it hotter...

I conclude from that fact alone, that resistance is decreasing as the cell warms. How else would current be able to increase?

I ran a cell today that began at 12 amps and as it ran, the current grew to 20 amps, and I shut it down because it was getting too hot. It is certain that current increases with heat. I don't know what resistance would be doing other than what Ohm's law would reveal and that is that as current is increasing, with a constant applied voltage, resistance must be decreasing. I don't think it is the temperature coefficient of the stainless, but of the electrolyte.
Agin i meant no disrespect for your cell, I actually think it is a great idea. and I await the day I read your results. It seems as though the reaction of the electrolyte allows for more current because of less resistance, in which case you are correct, it is the temperature coefficient of the electrolyte and its conductivity, not the plates. right?

[Riddler250]

PWM is my next series of studies, but first I am wanting to exhaust mechanical or physical cell designs that help to counteract the heating problem. I figure that with a combination of a good cell, and a PWM, I can RULE THE WORLD, or at least one little facet of my world.

At $90 for a tank of gas it isnt a little facet of my world. thats $270 a month. I brought that down a tank driving the spped limit on the highway. i have a good cruise control. I figure if i can get down to $200/month ill be kicking a**.

[fisher]

I am afraid of myself in this. I get just about 420 miles on a 15 gallon tank. If I could up that to 500 miles it would be nice. But then, I fear I will go for 600, then 700, ...

I am bad about improving things to the point of total catastrophe.

And yep, it is the water, not the plates.

As far as reading about my cell, between making it fit into my Accord, and deciding exactly what cell to build, it may be a while, and no telling what I will eventually decide to go with. Im just tossing out ideas as they occur to me from my studies and from thinking about it.

[Riddler250]

I am afraid of myself in this. I get just about 420 miles on a 15 gallon tank. If I could up that to 500 miles it would be nice. But then, I fear I will go for 600, then 700, ...

I am bad about improving things to the point of total catastrophe.

And yep, it is the water, not the plates.

As far as reading about my cell, between making it fit into my Accord, and deciding exactly what cell to build, it may be a while, and no telling what I will eventually decide to go with. Im just tossing out ideas as they occur to me from my studies and from thinking about it.

if I could go 420miles on a tank, i would be proud. I drive a 5.7liter v8 with a 30gallon tank. my wifes car goes about 500 on a 16 gallon tank. Sometimes there is a very fine line between total sucess and a total catastrophe. I have plenty of room for a cell, im just afraid i might buld one too big. Im thinking about getting a step up transfoemer and running 24v to a pelican case with 14cells. double the size, maybe double production. Im the same way. I think I might scrap my smacks booster, due to heat issues and go with something like smith03 has built. Ive had ideas about cells and powering them, but i always get on here and find someone that already tried it.

[fisher]

I read somewhere a (what I though was) good idea to add to your Smacks booster. The dude had taken old anti-freeze containers and cut the sides out of them. In the smacks, where a SS nut joins two plates, he had added a piece of the plastic as an insulator. It had holes big enough that the nuts went through the holes in the plastic, but the plastic was cut to fit tight in his container, so that no current could go through the electrolyte at that point, but had to go through the nuts. The purpose was to prevent current losses through the electrolyte.

Just in case somebody reading doesn't understand, a smacks has plates connected together with stainless nuts so that there is no voltage differental on the plates. The plates are alternated between being tied (electically) together, then separated by insulators, then tied, ... So installing the insulators doesn't hurt production, it just insures that current will not be flowing around the generator and is only flowing through the generator.

[redneckgearhead34]

I read somewhere a (what I though was) good idea to add to your Smacks booster. The dude had taken old anti-freeze containers and cut the sides out of them. In the smacks, where a SS nut joins two plates, he had added a piece of the plastic as an insulator. It had holes big enough that the nuts went through the holes in the plastic, but the plastic was cut to fit tight in his container, so that no current could go through the electrolyte at that point, but had to go through the nuts. The purpose was to prevent current losses through the electrolyte.

Just in case somebody reading doesn't understand, a smacks has plates connected together with stainless nuts so that there is no voltage differental on the plates. The plates are alternated between being tied (electically) together, then separated by insulators, then tied, ... So installing the insulators doesn't hurt production, it just insures that current will not be flowing around the generator and is only flowing through the generator.

Do you know what his results are like?

[fisher]

No, I don't just thought it was a neat idea.

[redneckgearhead34]

I was rethinking through my ap physics class and I had this idea.

Could you wrap a wire around a magnet and get current? idk I think so I have not tried it yet.

Let me know what you think

[Painless]

I was rethinking through my ap physics class and I had this idea.

Could you wrap a wire around a magnet and get current? idk I think so I have not tried it yet.

Let me know what you think

Not quite, but close. If you make a coil of wire and move a magnetic field through it you will generate current. This is the basis of an alternator.

[fisher]

One or the other has to be moving. The coil moves through the magnetic field, a generator. Or the magnetic field moves through the coil, a transformer. Either way, the turns of the coil have to be passing through magnetic lines of flux.

What were you trying to do? I have an idea that I may try someday of obtaining an old coil from a car, those things would generate several thousand volts from pulsating 12VDC. Hook that to a cell and see what blows up!

[redneckgearhead34]

One or the other has to be moving. The coil moves through the magnetic field, a generator. Or the magnetic field moves through the coil, a transformer. Either way, the turns of the coil have to be passing through magnetic lines of flux.

What were you trying to do? I have an idea that I may try someday of obtaining an old coil from a car, those things would generate several thousand volts from pulsating 12VDC. Hook that to a cell and see what blows up!

haha blowing stuff up is fun!!!! Just looking for a way to create electricity with out drawing it from my alternator.

Any ideas?

[Riddler250]

haha blowing stuff up is fun!!!! Just looking for a way to create electricity with out drawing it from my alternator.

Any ideas?

A semiconductor will convert heat to voltage, but Im afraid they arent very efficient.

[fisher]

Any ideas for generating voltage without pulling it from your alternator? Uhhh, a little monkey pedaling a bicycle connected to a generator? A second alternator installed? Oooh, a windmill as a hood ornament.

Seriously, why do you not want to pull if from your alternator? Your alternator should have the capacity to generate more than your car requires, and it is there. As I understand it, it does take some extra gas to generate extra amps from the alternator, but not enough to nullify the benefit of adding HHO generated in the process back into the engine.

My best idea, so far is the one concerning an old coil from a car, back in the day when cars had coils. Sort of a class C amplifier type setup.

[Riddler250]

Redneck, why this probably isn't the case for your car, the police cars I put together have a better alternator than stock and we pull close to 80a with everything running. I don't see why a stock alternator wouldn't have an extra 30 or even 50a unless you have a large stereo system

[redneckgearhead34]

Its not that I cant pull it from the alternator, if I can get electricity from some other source then in theory it should increase my gas mileage even more.

I was just brain storming but tell me more about these semiconductors they seem interesting.

Also I have thought of pulling a small windmill in my truck(forgetting the fact that is would look stupid) because it isnt very aerodynamic to start with.

[resago]

put a solar panel on your dash or back deck.

[Riddler250]

Its not that I cant pull it from the alternator, if I can get electricity from some other source then in theory it should increase my gas mileage even more.

I was just brain storming but tell me more about these semiconductors they seem interesting.

Also I have thought of pulling a small windmill in my truck(forgetting the fact that is would look stupid) because it isnt very aerodynamic to start with.

the easiest way i know to explain them is, my pool heater, just like any gas furnace has a flame, to heat air, or water, or whatever. in modern heaters or furnaces there is a thermalcouple (semiconductor) What this does is as the side touhing the flame heats up, the opposite side is cooler, this varience creates a voltage, that tells the gas valve to open when the varience reaches a certain point (the flame is burning) if the flame was to extinguish that temerature varience would drop, therefore the voltage would drop closing the valve (turning off the gas) its a safty feature built in. one thread on here talked about wrapping a series of thermalcouples around the exhaust manifold (to heat the one side, the other side will have a heatsink on it to dissapate heat, creating the temp. varience, therfore converting heat. the problem with these are that the efficiency of a thermalcouple is somewhere around 4-8%. the cost of these is dropping, but they are still very expensive, and you would need a lot of them to generate enough electricity. Im at work now and get yelled at for doing personal work on the computer so i dont have too much time to discuss this more, unless i charge my blackberry. OFF SUBJECT... Does anyone know at what RPM an alternator engages?

[Boltazar]

I like the monkey idea better