Pulsed signal 60% more effective then strait DC

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I wonder if actually quantifying the power being applied to the cell, in both straight and pulsed power setups would help "proof"the concept.

This would need to be done with a possibly smaller cell due to power limitations of batteries, but the procedure might be as follows:

R C modelers are quite adept at quantifying the capacities of their on-board battery packs.  They [capacities]determne the craft's performance and survivability.  Hardware is available in the form of in-line power meters, recording charger and discharge cyclers, as well as other devices that actually count the electrons, as it were, applied to charging a pack.

Using what is available, power your cell in question with just such a pack to a predetermined discharge voltage, straight DC.   Wait a predetermined period of time, [cooldown] and then recharge the pack.  Record the mA required to return the pack to full charge.   Now repeat the process several times, and you will get a clear picture of how many milliamps of current were applied to the cell to produce "X" volume of gas till the pack reaches the discharge threshold.

Now, using the very same pack, apply the pulsed approach to the cell, cut off at the same voltage, and measure output.  Repeat as above, counting the mA for the charge as what was applied for gas production.

[note- the charger will terminate charge at the same point regardess of discharge load.  Be sure to monitor pack temperature, as this affects charge reception (warm packs take less)]

Now the above seems a bit arduous at best, but it should provide some hard numbers on how much power was actually delivered to a cell over time, weighted against actual gas output.

I have all the equipment for such a test, but have yet to try it.  If I may,  I will use the above frequency and and duty cycle to perform a similar test in a couple weeks.  This would be valuable information if I get similar results.

And even if I don't get similar results it would be interesting to see the comparatives between what our power meters say we used, and what the actual battery mA delivered sez.   Methinks we shall see a gap.   More on that later

Turtle

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There is a formula found on page 12 [12 in the text] of this document



that delineates the means to accurately determine actual applied power.

Item 15 is the way they figger amps consumed in a pulsed  DC application.

I don't know calculus, but I was told this approach will more accurately reflect power than an RMS ammeter will.

I don't know; haven't tried it yet.   Still it should offer a more difinitive answer.  The whole document seems to agree with Steve's findings, tho funding was pulled before the researcher could difinitively prove the point.

Sound like a conspiriacy...

<groan>

Turtle

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There is a formula found on page 12 [12 in the text] of this document



that delineates the means to accurately determine actual applied power.

Item 15 is the way they figger amps consumed in a pulsed  DC application.

I don't know calculus, but I was told this approach will more accurately reflect power than an RMS ammeter will.

I don't know; haven't tried it yet.   Still it should offer a more difinitive answer.  The whole document seems to agree with Steve's findings, tho funding was pulled before the researcher could difinitively prove the point.

Sound like a conspiriacy...

<groan>

Turtle

Hi Keith,

I have seen that document before and i have read it too.
I do know you have similair cells as i have, so you must be able to replicate it.
If you want, i can help you setting it up.
Just send me a PM.

About that way of testing as you descriped, that is too much for me. I do my measurements with 2 scopes and 4 multimeters and math.
The scope is a true rms meter and i also did the math by hand by measuring the squarewave on the input of the circuit.
Because the voltage coming from the coil into the cell is DC, there is no rms calculation needed.

Best regards
Steve

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It seems that the coil is gaining some energy from somwhere

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Steve, can you explain what you are measuring exactly?
if you measure total input on a series cell and simultaneous the input at the cap it will seem that there is more power at the cap than total.
that is because voltage at coil and cap are out of phase with the voltage generator (+pi/2 at the coil, -pi/2 at the cap) and in resonance they cancel out, so you may have 10V in total but 100V at the coil and cap. that is why there are higher voltages at the parts than you feed in. the current is always the same at every part because it's in series.
there is no mysterious power coming from somewhere.

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Steve, can you explain what you are measuring exactly?
if you measure total input on a series cell and simultaneous the input at the cap it will seem that there is more power at the cap than total.
that is because voltage at coil and cap are out of phase with the voltage generator (+pi/2 at the coil, -pi/2 at the cap) and in resonance they cancel out, so you may have 10V in total but 100V at the coil and cap. that is why there are higher voltages at the parts than you feed in. the current is always the same at every part because it's in series.
there is no mysterious power coming from somewhere.

I use my parallel tubecell in this test. No seriecell, yet.
I also have not cap in this setup.
Just a stabilized powersupply.
Coil is in serie with the cell.
1 crowbar diode

Current before crowbar diode = 0.29amp
Current after crowbar diode with coil = 0.5amp

I know. Its strange.

Steve

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Pleading ignorance, what is a crowbar diode?

Thanks,

Turtle

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Pleading ignorance, what is a crowbar diode?

Thanks,

Turtle

Mea culpa,

Its a diode from negative to positive. From transistor/fet to positive wire, across the serie coil and cell.
Steve