Getting enough AMPERAGE !

[Bob]

When we consider running a car on 100% hydroxy gas we quickly run into a problem that we'd normially never run into...  getting ENOUGH AMPERAGE...
 at first you'ed think that all you have to do is add one or two of the largest Altenators you can get your hands on and your all set.... but thats only one part of the problem solved.... now that you have the Amperage AVAILABLE how do you get it to do the work that you actually want ?
...
  Usually when you try to max a cells output by raising the electrolyte concentration
you run up against a Wall and can't go any further, this is usually the point of saturation of water with the electrolyte used around 25% to 35% if I remember correctly by weight of KOH to water.... (yes that is a great deal of KOH !)
at this point you cannot increase the conductivity of the water any more ...
so what do you do if you still need More amperage ?
that is the problem that prompts this post... and I'll explore verious ways to accomplish reaching the goals of raising the amperage.
 First off the ratio of output of a cell is Directly related to the amount of Amps per square inch of plate area...  the lower the APSI (amps per square inch) the Lower the cells output, and the Higher the APSI the Higher the output AND HEAT.
so we find that there is a "Sweetspot" for the APSI and I've found it to be around 0.2 to 0.5 APSI
... any more than that will indeed raise the output a small amount but raise the heat much more.
...
So here is the problem... say I made a Cell from Pet Feeding dishes (stainless steel) with lots of area per plate in a compact form... my cell would have a Very large amount of plate area.
 Now sense the cell has an unusually large Plate area just feeding it the standard 20 amps just isn't going to cut it!, because the APSI will be abnormially LOW and the output will suffer dramitacilly because of it. infact getting 1/4LPM from such a large cell is par for the course when feeding it with low amounts of amps.
which is lousy for the standard cell (now 2LPM at 20amps is great output)
 this is Why building a big cell sometimes results in abject failure because the builder never gives it anymore than 20 amps and expects it to produce better because it has more plate area..... but it doesn't work that way More plate area demands more Amperage to USE that plate area well ! then you'll have better output
...
but when you make your large cell and discover as your making your electrolyte mix that you can only achieve 45amps at maximum concentration of the electrolyte
what do you do then ? when you figured out that your cell needs 100amps in order to have a APSI of 0.3 and you aren't even at the half way mark and can't go any further!
... this is the problem, and the solution is in the cell make up usually.
the closer the spacing on the plates allow you to draw more current
example: my 7plate test cell spaced at 1/4" plate spacing  gave me 18 to 20amps at Max concentration of electrolyte (KOH)
changing the cell to 1/8" plate spacing  changed that to over 40amps at max concentration.
so plate spacing does indeed effect the ability to draw more amps.
but as we all know there is a point where you can't get the plates any closer...
so then what do you do ? what if the cell your messing with is already as close as you can get the plates ? this is usually the case, or its just too much trouble to try and get the plate spacing any closer than they already are.
...
Your options are getting fewer and fewer as we move along down the line to higher amps... the electrolyte is at the saturation point now... and the plates are as close as you can get them...NOW WHAT ?
 Well you can divide the cell up into a bunch of smaller cells, in effect reducing the plate area of the cell... (I feel this is the reason you always see Mutable cells in Hydroxy powered vehicles...)
....
 if you had a 22 plate cell that maxed out at 60amp draw and you wanted 150 amps you'd have to divide that cell many times into smaller cells say 7plates each or so.

 your Max concentration in the electrolyte stays the same but you can reduce the amount of plate area of the "individual cell itself" and that raises the APSI
 this actually changes your cell design but it is a way around the problem.
...
 using this method you could run 4 cells at 40 amps each for a total of 160amps
and still have the proper APSI for the cells to operate at their best efficiency
.... (try getting 160amps in a single cell otherwise ! )
..
another method is to change the voltage Up from 12volts to a higher voltage
changing the voltage to a higher voltage pushes the Amperage through the cell easier... so you can get More "POWER" to your plates even if there's 22 of them in line... this method usually involves using an inverter to change the DC voltage to an AC voltage and step up the volt's by taking away some amps...
 Personally I think this method is a bit more complicated than what it is worth and ends up costing you precious electrical power in the process... make no mistake "Inverters" are Hungry little parasites!
...
so... if you want to run 200amps there are a few things to keep in mind
 you want to run as High a concentration as possable, usually to the saturation point of KOH and Water... because you want the lowest resistance through the electrolyte you can get to lower the heat generated as much as possable.
...so from that you want to figure your MANY cells at max concentration at what ever amperage you can get from that from your cell design... say 50amps per cell
and calculate your plate area to achieve 0.2 to 0.5 amps per square inch.
this would leave you with 4 cells running 50 amps each or 200amp total
...
depending on your individual cell output you add them all up for the total LPM output....
....
 Remember however that running higher amperage means Much more heat ! if you run
200amps at 12vdc that's 2400 watts of heat that you will have to dissipate...
(that's the equivalent of a 5000watt heater on medium all the time... a huge amount of heat!) if you don't handle the heat properly you'll have problems with melting plastic, steam instead of HHO and thermal runaways....
....
its my view that a 5 gal bucket with aluminum flashing wrapped around it and made into cooling fins will probably dissipate 5000watts of heat if the electrolyte is circulated well enough... however this is "untested" <grin> (yah I'm guessing!)
....
so there ya have it....
I don't know any other ways of controling the amps... if you do please post them !
...
thanks !
Bob........





 

[Manta]

Bob,

Just reading through your post.  What size is the 'standard cell' you refer to ?.  How many plates ?

....so we find that there is a "Sweetspot" for the APSI and I've found it to be around 0.2 to 0.5 APSI...

....which is lousy for the standard cell (now 2LPM at 20amps is great output)....


I was thinking along the lines of  2LPM at 20 Amp = 1 LPM at 10 Amp.  If you had a simple two plate cell and the plates were 5" square then you would have 25 Sqr Inch.

Now that would give you only 1/25 = 0.04 APSI

If you double that to get back to the 2 Litre at 20 Amp then you still only have 0.08 APSI.

This is a whole order of magnitude less than the sweetspot figure you suggest.

Manta

[Bob]

Manta:
 Twas just a figure of speech really <GRIN> what I refure to as a standard cell  probably isn't the standard cell by Your standards ok ?  My standard cell is the Randy cell...mainly because I know it best
and it produces very well for its small size... it has 11 2"washers with a 1/2" hole in each washer in the center... I estimated the plate area at 52sqr inches at one time I think, but I calculate only one side of each plate... not both sides
 so your 5"x5" 2 "PLATE"(2x25=50) cell will have 50"square powered by 20 amps is 0.4 APSI
(20/50)=0.4 amps per square inch which would be right in the "Sweetspot" I was talking about.
...
....(20 amps will go into 50square inches of plate area=0.4  so each sqr inch has .4amps on it.)
...
 Knowing HOW I calculated these figures is necessary to understanding my
logic... I am sure... so, what I am calling APSI may not be APSI to another way of figuring it... that's WHY I explain in detail ! LOL
...
 Actually I don't know how you came up with your numbers, and I have seen others referring to extremely low amps per square inch figures and saying that is where you want to run the cell at... which boggles my mind HAHAHAHA  so perhaps I am figuring it wrong AGAIN EH ?


if I'm wrong please explain it to me ! <GRIN>

Bob......

 

[Manta]

Bob,

Your right.  I missed a zero and didn't notice it. Hence my 'order of magnitude' error.  Sorry about that.  glad you picked it up.
re the plate are. I only include the 'sending' plate, not the receiving plate when I do the calculations.

Manta

[ROADKING]

When you figure square inches are you using both sides of one plate or just one, and is this just the negative or positive, or both?  Then does the neutrals have anything to do with this?  Is there any reason for neutrals other than heat and amp issues, If that is the only reason I have a constant current pwm that should take care of those problems, how ever I do run neutrals,
The reason I am asking these question now, I have found a new thing on the net to try.  I read where you can now put a 400 watt inverter on your battery to go from 12 dc volt to 120 ac volt, now take a power supply from a computer and plug it into the inverter and take the wires from you power supply from the pc and wire your cell,  these wires from the pc put out a range of volts from 3.5 to 15 volts I think is what it said.  Now they clam you can use the 3.5 volt wires at like 15 amps get great lpm with no heat issue?  Therefore you would need no pwm.  Anyway this is why I am asking how to figure for a new cell?  Any input on this would be greatly appreciated.

[Bob]

No problem Manta glad to help !
...
Roadking:
  I cannot tell you the PROPER way of calculateing plate area of a cell because I don't know if there is an accepted STANDARD as of yet to do it Properly!  But.... How I do it is like this....
....
 I calculate the Plate area of a cell by the Length times width of the plate times the number of plates
 I do NOT count both sides of the plate even though one side is pos and one side is neg (as in a neutral plate)... I simply treat it as ONE plate...period!
... for example if I have  a +,N,N,N,N,- arrangement  I count each place(or plate) which is 6 in this case.(2 powered plates or driven plates and 4 neutral plates).
  if the plates are 4"x5" the plate area for one plate is 4"x5"=20sqr inches....
now sense there are 6 plates total, its 20sqr in. times 6  or 180sqr inches of plate area.
...
so you see that I include the Neutrals in the calculation,as well as the powered plates...I treat them all the same.
...
Now takeing it to the next step of calculating the amps per square inch of that same cell.
lets say we plan on running 30 amps into this cell lets see how it works.
at 30amps /180=.1666 amps per square inch... which is low compared to .2~.5 of our "Sweetspot" numbers...
 so lets up the amperage to 50amps and see if that puts us in the ball park.
50/180=.2777APSI.... which is at the bottom of the scale
60/180=0.33333 APSI which is in the ball park now.(at 60amps!)
..
So You can see that the make up of the cell itself will tell you how much amps it will take to run it efficiently... and get the most output and least heat combination that you can get... or at least close to it. if you make your cell to run in the Mid to high "Sweetspot" Area for amperage you can almost be assured of 2LPM at a minimum... and mutable of that every 20amps so running 60amps should get you 4~6LPM... which is very healthy output !
...
 but you MUST realize that MOST people never push their cells this hard... they would typically only put 25 amps to this cell and not have any heat issues with it at all... but the output will be extremely LOW for what YOU COULD BE GETTING!
if you run your APSI at the "Sweetspot" calculations rest assured you will have HEAT issues if you don't ave some way of handling the heat !
...
  so if You make a cell let "IT Tell you" how many amps it wants... you'll be happy you listened to it ! <GRIN>

As far as using a computer's power-supply, I wouldn't bother myself although I might use a voltage dropping resistor setup and or a current Limiting circuit
if those issues are a concern to you...
 remember if you have a HEAT issue the best thing you can do is run MAX concentration of the electrolyte, and then control the amount of amps going through the cell. this gives you the best of both worlds with as little heat as possible...
 getting rid of the PWM is easy enough, if you put in a current limiter in line with the cell... if your current limiter is set at 25 amps the cell cannot draw more than 25 amps no matter what... although they take time to warm up and get going
on cold mornings its better than having a part in line that can get fried accidentally, if you turn the knob too far!
...
Hope that helps !
Bob........

[ROADKING]

Ok Bob,
Thanks for that information and that is the way I remember doing as of about 1 year ago, but I was getting confused when I read you last post but that is easy for me LOL.  I am using a ccpwm rated at 150 amps and seems to work well and they are reasonable in price of $100.00.  So far as neutrals, Zero Fossil claim to use neutrals as a volt splitter equaling 2.5 volts per plate, and I think this is right for Denmark is having great success at this, for they are making tons of electricity with wind mills so they can power these cells with success.  They claim 2 volts to the plate.  Now where do I get a current limiter?  Thank you for the explanation.

[crb]

Bob,
if the plates are 4"x5" the plate area for one plate is 4"x5"=20sqr inches....
now sense there are 6 plates total, its 20sqr in. times 6  or 180sqr inches of plate area?

Bob, Is this correct?? If so could you elaborate.

crb

[Bob]

CRB:
 Yes, But Remember this is JUST HOW I DO IT...even if I got the math wrong!
 I have discovered that many people calculate their plate area in different ways.
 (On a DRY CELL you Must only calculate the Whetted surface area... not the entire metal Plate.)
...
"if the plates are 4"x5" the plate area for one plate is 4"x5"=20sqr inches....
now sense there are 6 plates total, its 20sqr in. times 6  or 180sqr inches of plate area"
...
 the surface area of rectangle is length times width, so 4"x5"=20"...
(this also works for square plates)
sense each plate is 20Sqr inches of surface area,and there are 6 plates its 6x20=120sqr inches (not 180, sorry thats what I get for going it in my head!)
....
this will obviously change the APSI calculations too ...
so ...
"Now taking it to the next step of calculating the amps per square inch of that same cell.
lets say we plan on running 30 amps into this cell lets see how it works.
at 30amps /120=.25 amps per square inch... which is a tad low compared to .2~.5 of our "Sweetspot" numbers...but is still useable.
 so lets up the amperage to 50amps and see if that puts us in the ball park.
50/120=.4166APSI.... which is at mid range to high on the scale
60/120=0.5 APSI which is at the top of the scale (at 60amps!)"
...
Thank you for catching that Math error CRB I appreciate it !
and it actually made a big difference in the APSI calculations it turns out that ALL of the amps used were in the ball park at some point.
 Now, although not many people Run .5APSI it is a very good producing amount of amperage. but with it comes More heat so you have to be aware of that and go accordingly. the "Randy cell" has an APSI of .25APSI if I remember correctly
and it produces at a 10:1 ratio of amps to Liters output.... this is very good
so I try very hard to get my cells to at LEASE this High or Higher...in APSI.
...
Voltage on the plates is a concern when  they are NOT in a Parallel Hookup as in a Cell with a bunch of Neutral plates in it and the power to each plate is INDUCED to each plate in the line...
 the ideal voltage per plate is above 1.24volts per plate as it takes at LEAST that much voltage to make it work... again a bit more is better, but not too much
... so saying 2v per plate is right on the button actually...
there is allot of room to play with in the workings of a Hydroxy cell, they will work fine with 12v per plate or 120v per plate its just the more voltage you have above 2 volts  just goes into making heat (from what I've been told anyway)
... of the two things here APSI and plate Voltage,...BOTH ARE ESSENTIAL to a good working cell, without enough voltage the cell will not produce much, and without enough amperage the cell will not produce much... but with the proper amount the cell will produce a great deal of output!...in what EVER configuration you choose
...
we have talked before about lowering the voltage on 2 parallel type cells like the "Randy Cell" by running them in series  and each cell gets 6 volts instead of 12v
and the cells do work good this way....
  However when I tried this, I wound up changing it back to a parallel hookup so each cell would see 12v instead and the output was better by far.(which is weird because there should be no difference in the output only the heat generated!)
I was also running 30 amps total for 2 cells so that's only 15 amps each... so I think that accounts for the discrepancy... I needed about 45 amps to do it in series
I think and then there wouldn't have been any change in output, just the heat output
.... at least I think so, I havn't tried that yet to prove my thoughts.
...
when running Mutable cells strange things start happening.  and don't think for a second that you can run 2 cells at the same amps as one... and have an increase in LPM output.... you won't... your output will be the same as with 1 cell if you use the same amps to run 2 cells.... if you want double the output you MUST double the amps used !
...so the question becomes WHY use 2 cells at 40 amps when 1 cell at 40 amps will produce the same ? ...well because it won't really...there is a SLIGHT gain , something like 1/4LPM from running 2 cells at 40 amps rather than 1 cell at 40amps
(this is with "Randy cells"but should be consistent with ALL cell types)
and the HEAT output of running 1 cell at 40 amps is MUCH MUCH higher than the heat output of 2 cells at 40 amps.... one will melt the plastic cap on the container it gets so hot , and the other will be warm to the touch is all.
so mainly Heat and a slight increase is the reasons for running 2 cells at 40 amps rather than 1 cell at 40amps.
...
Bob....

[Manta]

Bob,

Just to keep the pot boiling.

....and don't think for a second that you can run 2 cells at the same amps as one... and have an increase in LPM output.... you won't... your output will be the same as with 1 cell if you use the same amps to run 2 cells....

I don't see how this can be.  Basically you seem to be saying that if I had two vehicles parked side-by-side and each was producing, say. 5 litre per minute,  if I joined the two outlets from the cells together into a 'tee' I wouldn't get 10 litre per minute from the pair.

The above is the same as having two separate cells in one vehicle,  each drawing the same current and each producing the same volume of gas. Ie each producing 5 Litre per minute.  The output has to be the sum of the two inputs.

Manta

Who is losing hair through too much head-scratching.

[Bob]

HAHAHAH
Manta:  What you said is correct, connecting the output from the 2 cars would give you 10LPM....
 Let me clarify what I said...
  say you have one cell running in your car...and it puts out 2LPM at 20 amps
you get a wild hair.... and decide to put another cell along side it and run them BOTH on the same 20amps....because you don't want to load down your standard alternator much....  if you do this you will still have the same OUTPUT as with a SINGLE cell.... in-other-words you will be running 2 cells on 10amps each instead of one cell at 20 amps.... OK ? you will wind up with a tad less than the original 2LPM output....
  what you have to do is Increase the Amperage or like in your example have 2 units complete with their power supply/amperage.... to make it work if you try to skrimp on the amps you are shooting yourself in the foot!
...
 one cell running at 20 amps gives 2LPM, if you add another you then would have 2 cells at 40amps and get 4LPM...... HOWEVER if you try to run the 2 of them on the same amps as you did the 1 cell.... you'll wind up with the same output  that you had in the first place.... that's all I am saying ....
and you can Bank on that, because I did just exactly that and found out the hard way....  I thought I could run 2 cells at 20 amps and get 2 times the output and this is NOT TRUE !... if you want to double your output by adding another cell you have to add that much MORE amperage than you are already running now.
...
if I had a 4LPM dry-cell running 45 amps and decided to add another cell so I'ed have 8LPM total I would have to Add another 45 amps for a total of 90amps to get that 8LPM... so each cell receives its 45 amps ...
if I tried to run both of those cells on Just 45amps the output would be just a tad less than the original 4LPM...
conversely.... if I tried to run One cell on 90amps I'd probably get about 7.5LPM and a bunch of heat in the bargain...
....
if you want to "DOUBLE UP" on the cells you have to double up on the amperage as well....
...
I had the Wrong idea when I did it... I thought all I had to do was keep adding Cells ...but adding cells is only part of it, you have to keep adding the AMPS as well !
...
understand ?
...
Bob......

[Manta]

Bob,

I think I see where things are getting mixed up.

I assumed that if you are going to put two (say 10 Amp draw) cells in the car that you would expect to get a 20 amp current draw. After all, if to put two 100 Watt lamps across the charging system you would expect to draw twice as much as one lamp.  Each would draw 100/12 = 8.33 Amp.  And a 10 Amp cell equates to 120 Watt.
I didn't realize that you were reducing the current (probably by weakening the electrolyte) to get back to 5 amp per cell and thus a 10 Amp total.

Manta

[Bob]

Exactly !
 but believe it or not allot of people do have this misunderstanding, heck I did!
the Misunderstanding comes ( I believe) from not taking the cell and amps TOGETHER as a unit... it takes a certain amount of amps to get the LPM output from the cell
 and if you add another cell, you have to add the amps to it as well !
 Kind'a Like...
a bucket full of water.... you can add another bucket full of water and have 2 buckets full... but if you only have one bucket of water and divide it between 2 buckets you have 2,  1/2 full buckets... which is the same as one full bucket
...  so what you want to do is add another bucket Full of water (where the bucket is the cell and the water is the amps used and/or output produced)
... if you follow my illustration ! HAHAHAHA
(and if that doesn't confuse ya nothin' will HAHAHAH Oh well I tried!)
....
Bob......

[Manta]

Bob,

Sorry,  but I can't resist this.

....a bucket full of water.... you can add another bucket full of water and have 2 buckets full..

No you can't,  it was already full so you couldn't add any more.

 

Merry Christmas to all.

Manta

[Bob]

HAHAHAH ! humm your right ! well add a bucket too then  !
...
And Merry Christmass to all !
...
Bob.....