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Robert Adsett
Posted: Fri Jun 08, 2007 10:11 pm
 
In article <1181306147.880719.176660@p77g2000hsh.googlegroups.com>,
says...
[quote:17fc426204]On Jun 7, 8:20 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
In article <1181259760.318128.268...@w5g2000hsg.googlegroups.com>,
says...

But my variable load electrolyzers are 85% efficient in the
electrolysis step. Proton Exchange Membranes (PEM) can be even more
efficient (single step) but not by much - but the costs are
tremendously high. The advantage of PEM is that you can go either way
with fair efficiency - 80% electricity to hydrogen to electricity -
under ideal condtions -but these fall off rapidly in less ideal
conditions..

Where do you get a > 80% efficient PEM cell?


http://waterfuelcell.org/WFCprojects/Tero/series_cell_v1.2.pdf
[/quote:17fc426204]
Well it's not PEM, it's not > 80% efficient (and I don't trust the
figures they do give). Giving a link to a site promoting > 100%
efficient electrolysis is a VERY bad start. It's also not commercially
available which would seem to be a minimum requirement to meet your
claims(1).

The link does give a rather, um, interesting approach. They split water
and place the results into a single container. Yes, hydrogen and oxygen
together, the mind boggles.

(1) It's worth emphasizing that to meet your claim you need to have a
cell that provides on the order of 90% efficient in each direction to
get that 80% round trip figure.

Robert

--
Posted via a free Usenet account from http://www.teranews.com
 
Guest
Posted: Sat Jun 09, 2007 3:07 am
 
On Jun 8, 11:11 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
[quote:b3a0a9f632]In article <1181306147.880719.176...@p77g2000hsh.googlegroups.com>,
says...





On Jun 7, 8:20 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
In article <1181259760.318128.268...@w5g2000hsg.googlegroups.com>,
says...

But my variable load electrolyzers are 85% efficient in the
electrolysis step. Proton Exchange Membranes (PEM) can be even more
efficient (single step) but not by much - but the costs are
tremendously high. The advantage of PEM is that you can go either way
with fair efficiency - 80% electricity to hydrogen to electricity -
under ideal condtions -but these fall off rapidly in less ideal
conditions..

Where do you get a > 80% efficient PEM cell?

http://waterfuelcell.org/WFCprojects/Tero/series_cell_v1.2.pdf

Well it's not PEM,
[/quote:b3a0a9f632]
That's true its just plain old stainless steel My understanding is
that for very sound fundamental reasons PEM is far more efficient than
plain old stainless steel. If you can show plain old stainless is
more efficient than PEM I'd like to see it.

[quote:b3a0a9f632]it's not > 80% efficient
[/quote:b3a0a9f632]
Yes it is. Its over 80% efficient electrolyzer and it talks about why
the shape of the power is important - it quite specifically talks
about actually building stuff and explains things in gory detail -
specifically answering the original poster's questions and supporting
nearly everything I said in response to it.

[quote:b3a0a9f632](and I don't trust the
figures they do give).
[/quote:b3a0a9f632]
Why is that exactly? They go into detail relating the volume of gas
at STP to precise measurement of power they give. They lay everything
out in a lot of detail. What details did they get wrong?

[quote:b3a0a9f632]Giving a link to a site promoting > 100%
efficient electrolysis is a VERY bad start.
[/quote:b3a0a9f632]
First off, I didn't say anything about the site, I referenced the
paper which was quite detailed. Please show me where anyone said
anything about >100% efficiency. They didn't. They spoke of APPARENT
[quote:b3a0a9f632]100% efficiency due to volume changes because they were not at STP
conditions. They explained why some people sometimes make such claims[/quote:b3a0a9f632]
and were careful to show how such bogus results are sometimes arrived
at. That you believe that means they are making claims of >100%
efficiency indicates to me you either didn't read the paper with
understanding, or understand the paper perfectly well, but have your
own agenda going on. In either case, you are wrong in your statement
here.

Fact is, the paper gives a detailed step by step process whereby
anyone can electrolyze water into oxygen and hydrogen and do so in a
way that allows them to accurately estimate efficiencies by measuring
power consumed on the one hand, and measuring volumes of gas on the
other, adjusting for temperature and pressure.

They also ran a small engine intermittently only oxygen and hydrogen
which I thought was rather instructive as well.

[quote:b3a0a9f632]It's also not commercially
available which would seem to be a minimum requirement to meet your
claims(1).
[/quote:b3a0a9f632]
??? Since when was it impossible for a company to manufacture
stainless steel products ??? And what does this have to do with
efficiency claims ???

[quote:b3a0a9f632]The link does give a rather, um, interesting approach. They split water
and place the results into a single container. Yes, hydrogen and oxygen
together, the mind boggles.
[/quote:b3a0a9f632]
This does not invalidate their response. The bottom line you have
said nothing that invalidates my comment that quite inexpensive
electrolyzers can be built that are highly efficient.

[quote:b3a0a9f632]
(1) It's worth emphasizing that to meet your claim you need to have a
cell that provides on the order of 90% efficient in each direction to
get that 80% round trip figure.

Robert

--
Posted via a free Usenet account fromhttp://www.teranews.com- Hide quoted text -

- Show quoted text -[/quote:b3a0a9f632]
 
Eeyore
Posted: Sat Jun 09, 2007 4:32 am
 
Willie.Mookie@gmail.com wrote:

[quote:1f4dc6ba33]Eeyore wrote:

You're suggesting that world-reknowned brands Varta and Sony are lying > about the capacity of their batteries ?

I am suggesting that any real progress would be reported in the
literature
[/quote:1f4dc6ba33]
Whose literature ? Have you never heard of commercial secrecy ?


[quote:1f4dc6ba33]and that any claims of progress should be backed by
references to that literature - as I routinely provide you regarding
my comments.
[/quote:1f4dc6ba33]
So, it can't exist unless a bunch of out-of-touch, superannuated, waste-of-space academics agrees it can ?

God, you're stupid !

Graham
 
Eeyore
Posted: Sat Jun 09, 2007 4:35 am
 
Willie.Mookie@gmail.com wrote:

[quote:9ae2edbbc9]I don't have any peer reviewed papers in the literature to back up my claims of a 3 fold increase in power to weight for NiMH
batteries. Got it! haha.
[/quote:9ae2edbbc9]
Yes, I can see you're a Grade A loonie.

Graham
 
Guest
Posted: Sat Jun 09, 2007 8:41 am
 
On Jun 9, 5:32 am, Eeyore <rabbitsfriendsandrelati...@hotmail.com>
wrote:
[quote:eb0c284522]Willie.Moo...@gmail.com wrote:
Eeyore wrote:

You're suggesting that world-reknowned brands Varta and Sony are lying > about the capacity of their batteries ?

I am suggesting that any real progress would be reported in the
literature

Whose literature ? Have you never heard of commercial secrecy ?
[/quote:eb0c284522]
Improvements as fundamental as the type you are suggesting would be
haralded in the literature. Obviously you don't read that literature
so you are unaware how that works, and how secrecy is maintained.
haha.. 3M for example promoted its giant birefringent optics through
the professional literature while maintaining tight control of the
core technology. I am certain any fundamental improvement in battery
technology would be treated comparably, if it exists.

[quote:eb0c284522]and that any claims of progress should be backed by
references to that literature - as I routinely provide you regarding
my comments.

So, it can't exist unless a bunch of out-of-touch, superannuated, waste-of-space academics agrees it can ?
[/quote:eb0c284522]
Pretty much. if by 'out-of-touch, superannuated,waste-of-space
academics' you mean folks who know what the hell is going on. yeah.

[quote:eb0c284522]
God, you're stupid !
[/quote:eb0c284522]
I now you are but what am I?

> Graham
 
Guest
Posted: Sat Jun 09, 2007 9:45 am
 
THE PARAGRAPH ABOVE THAT SAYS

The US has 245 tons of easily recoverable coal reserves. This is
sufficient to provide 1,715 barrels of gasoline - more than double
the
amount of hydrocarbons presently left in the world today - and enough
to supply the coming shortfall for over 50 years as older oil fields
all enter secondary production.


SHOULD SAY

The US has 245 billion tons of easily recoverable coal reserves. This
is
sufficient to provide 1,715 billion barrels of gasoline - more than
double the
amount of hydrocarbons presently left in the world today - and enough
to supply the coming shortfall for over 50 years as older oil fields
all enter secondary production.

AN INTERESTING POINT

The word 'billion' in this paragraph was there before I pressed [send]
button. I don't know what happened to it. But I am just saying without
any judgement whatever, the word 'billion was there before I pressed
[send] How do I know this? I copied it from a word processor and
pasted it in this window. And the word is THERE! haha..

So, there ya go.

Should someone start a site dedicated to usenet consistency? Just a
thought.

But I digress - which is the point perhaps.

Cheers
Bill
 
Eeyore
Posted: Sat Jun 09, 2007 10:18 am
 
Willie.Mookie@gmail.com wrote:

[quote:5e2b90d779]Eeyore wrote:

Your blinkered outlook is truly amazing.

Yeah,asking for pointers to literature that discuss a claim of
fundamental improvement in bonding energy of an electrochemical
reaction is pretty conservative, I'll admit it.
[/quote:5e2b90d779]
Why would Varta want to give away their trade secrets ?


[quote:5e2b90d779]You 'believe' only in what you want to believe.

No, that would be you Graham. I asked for evidence.
[/quote:5e2b90d779]
The evidence is in the High Street you damn idiot - where you can BUY ONE ! How much
more 'evidence' do you need ?

Graham
 
Williamknowsbest
Posted: Mon Jun 11, 2007 1:45 am
 
On Jun 9, 11:18 am, Eeyore <rabbitsfriendsandrelati...@hotmail.com>
wrote:
[quote:e0d05df16f]Willie.Moo...@gmail.com wrote:
Eeyore wrote:

Your blinkered outlook is truly amazing.

Yeah,asking for pointers to literature that discuss a claim of
fundamental improvement in bonding energy of an electrochemical
reaction is pretty conservative, I'll admit it.

Why would Varta want to give away their trade secrets ?

You 'believe' only in what you want to believe.

No, that would be you Graham. I asked for evidence.

The evidence is in the High Street you damn idiot - where you can BUY ONE ! How much
more 'evidence' do you need ?

Graham
[/quote:e0d05df16f]
Um, I'm not doubting I can buy one. But why the hell should I go to
the trouble and take my equipment and lab space to do a measurement
that you'll just tell me I did wrong anyway? GIVE ME A FREAKING
POINTER TO A PEER REVIEWED PAPER DONE BY AN INDEPENDENT LAB OR CUT
YOUR BLATHER! haha.. You talked big about secrets. Hell, Graham, it
doesn't reveal any secrets to measure the power output of a AA cell
and compare it to its weight! SHeez. But you can't point to one
consumer report or one independent lab that verifies what you claim?
Something this revolutionary would have been all over the battery
press. And it would be patented anyway. So, there'd be plenty of
information on it. If it exists. So, WHERE IS IT? That's all I'm
asking. I am making no judgments. I am merely asking for solid
verifiable data to back up what you claim about a fundamental
improvement in bonding energy for NiMH batteries.
 
Robert Adsett
Posted: Mon Jun 11, 2007 10:19 pm
 
In article <1181545591.201413.56700@c77g2000hse.googlegroups.com>,
Williamknowsbest says...
[quote:ef44edf06a]On Jun 9, 5:59 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
In article <1181376476.771491.24...@k79g2000hse.googlegroups.com>,
says...

On Jun 8, 11:11 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
In article <1181306147.880719.176...@p77g2000hsh.googlegroups.com>,
says...

On Jun 7, 8:20 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
In article <1181259760.318128.268...@w5g2000hsg.googlegroups.com>,
says...

But my variable load electrolyzers are 85% efficient in the
electrolysis step. Proton Exchange Membranes (PEM) can be even more
efficient (single step) but not by much - but the costs are
tremendously high. The advantage of PEM is that you can go either way
with fair efficiency - 80% electricity to hydrogen to electricity -
under ideal condtions -but these fall off rapidly in less ideal
conditions..

Where do you get a > 80% efficient PEM cell?

http://waterfuelcell.org/WFCprojects/Tero/series_cell_v1.2.pdf

Well it's not PEM,

That's true its just plain old stainless steel

More to the point it's an alkaline cell. In my experience with fuel
cells the alkaline units I saw were substantially more efficient than
the PEM units. Although to be fair they were not as far along the
commercialization route.

Yes.

My understanding is
that for very sound fundamental reasons PEM is far more efficient than
plain old stainless steel. If you can show plain old stainless is
more efficient than PEM I'd like to see it.

You just did. You've yet to show a PEM unit that comes close to your
claim.

Well, there are Alkaline Units, Polymer PEM, and Solid Oxide Ceramic
Exchange Membrane - it seems pretty straightforward to go look up the
best available in each of these classes wouldn't you say?
[/quote:ef44edf06a]
Hey, you are the one who claimed the existance of > 80% PEM cells. All
I was asking for was an example, I've not seen one. I've seen fuzzy
references to 60% for a bare stack, but that becomes considerably less
when balance of plant etc... is taken into account. However, I've not
seen a pointer even to that.

The best actual PEM cell I've actually seen was considerably less than
50%, although getting efficiency figures out of manufacturers data
sheets can be quite an excercise. I'm not actively searching for a cell
at the moment so I'm not inclined to do the excercise for many
manufacturers out there, even the few you can get data sheets from. If,
however, there was an 80% cell I would be interested in it.

[quote:ef44edf06a]

it's not > 80% efficient

Yes it is. Its over 80% efficient electrolyzer and it talks about why

They claim 80%, you need quite a bit above that to meet your round trip
claim.

Yes you do - you need 90% each way to get to 81% round trip
[/quote:ef44edf06a]
Maybe even higher than that, I thing mentioned in my wanderings is that
convetionally Fuel cells use the lower heating value when calculating
efficiency and electrolyzers use the higher heating value. If that
holds ther's an additional nearly 15% to account for leading to a need
for on the order of 97% efficiency for each.

[quote:ef44edf06a]
the shape of the power is important - it quite specifically talks
about actually building stuff and explains things in gory detail -
specifically answering the original poster's questions and supporting
nearly everything I said in response to it.

(and I don't trust the
figures they do give).

Why is that exactly? They go into detail relating the volume of gas
at STP to precise measurement of power they give. They lay everything
out in a lot of detail. What details did they get wrong?

They haven't done any measurements of how much hydrogen they actually
have. As opposed to say water vapour. I'd expect a fair amount of the
latter given the description. The also don't measure voltage drop to
see where it's occuring. They have made no attempt to determine leakage
current.

These are good points. Any idea how much these are likely to change
their efficiency estimates? PLUS or minus 2% perhaps?
[/quote:ef44edf06a]
At a guess 50% wouldn't surprise me.

[quote:ef44edf06a]
Finally I believe they've used the wrong figures for
determining efficiency from voltage drop even if they did have proper
figures to start with.

Please explain that. What did they get wrong specifically? Its all
there, if they made a mistake you should be able to tell me
specificially what the mistake is. I'm the one that scanned it and I
admit they may have made one I didn't see. But if you saw a specific
mistake, then it should be easy for you to say what it was shouldn't
it? But you didn't say. So, I'm asking you.
[/quote:ef44edf06a]
Specifically I'm concerned about their use of 1.48V for their
electrolyzing efficiency in the calculations. I think they are
including voltages other than those contributing to electrolysis and
getting artificially high efficiency figures as a result.

[quote:ef44edf06a]Giving a link to a site promoting > 100%
efficient electrolysis is a VERY bad start.

First off, I didn't say anything about the site, I referenced the
paper which was quite detailed. Please show me where anyone said
anything about >100% efficiency. They didn't. They spoke of APPARENT

http://waterfuelcell.org/Peoples%20Projects.html

This isn't the paper I cited is it? haha.. NO!
[/quote:ef44edf06a]
It's the site you cited. Any post on a perpetual motion site will be
heavily discounted. Period.


[quote:ef44edf06a]but you should know better.

About what precisely? These vauge dismissive comments with no
referent.
[/quote:ef44edf06a]
That references are judged partially on the company they keep. I
wouldn't expect references to papers on flight that lead to a UFO site
to be taken highly seriously either.

Robert

--
Posted via a free Usenet account from http://www.teranews.com
 
Williamknowsbest
Posted: Wed Jun 13, 2007 10:23 am
 
On Jun 11, 11:19 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
[quote:d175efbe4c]In article <1181545591.201413.56...@c77g2000hse.googlegroups.com>,
Williamknowsbest says...





On Jun 9, 5:59 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
In article <1181376476.771491.24...@k79g2000hse.googlegroups.com>,
says...

On Jun 8, 11:11 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
In article <1181306147.880719.176...@p77g2000hsh.googlegroups.com>,
says...

On Jun 7, 8:20 pm, Robert Adsett <s...@aeolusdevelopment.com> wrote:
In article <1181259760.318128.268...@w5g2000hsg.googlegroups.com>,
says...

But my variable load electrolyzers are 85% efficient in the
electrolysis step. Proton Exchange Membranes (PEM) can be even more
efficient (single step) but not by much - but the costs are
tremendously high. The advantage of PEM is that you can go either way
with fair efficiency - 80% electricity to hydrogen to electricity -
under ideal condtions -but these fall off rapidly in less ideal
conditions..

Where do you get a > 80% efficient PEM cell?

http://waterfuelcell.org/WFCprojects/Tero/series_cell_v1.2.pdf

Well it's not PEM,

That's true its just plain old stainless steel

More to the point it's an alkaline cell. In my experience with fuel
cells the alkaline units I saw were substantially more efficient than
the PEM units. Although to be fair they were not as far along the
commercialization route.

Yes.

My understanding is
that for very sound fundamental reasons PEM is far more efficient than
plain old stainless steel. If you can show plain old stainless is
more efficient than PEM I'd like to see it.

You just did. You've yet to show a PEM unit that comes close to your
claim.

Well, there are Alkaline Units, Polymer PEM, and Solid Oxide Ceramic
Exchange Membrane - it seems pretty straightforward to go look up the
best available in each of these classes wouldn't you say?

Hey, you are the one who claimed the existance of > 80% PEM cells.
[/quote:d175efbe4c]
Its not a claim dude. Fuel cells are NOT limited by the same
thermodynamic relations that a heat engine is.

I don't know what your problem is. You are a knowledgeable person.
Its common knowledge that under large loads and the higher
overvoltages to create them fuel cells have about 60% efficiency as
you say at their peak power density.

But under low loads with high quality oxygen and hydrogen inputs they
have greater than 90% efficiency! .

Plainly operating a fuel cell under the appropriate load to produce
high efficiencies increases efficiencies to over 90%. So, 90% or more
is possible under ideal conditions.

Now, one immediately comes up against the idea that hey, you can get
high thermal efficiencies but the capital efficiency sucks! You
drop the current density to 0.1 A/cm2 and the cost per watt increases
five times from when you run at 0.6 A//cm2!

So, you've got superlative efficiencies, but who can afford it?

Now I ask you, what if there were a membrane that was 1/2% the cost of
Nafinol available?

That would change things wouldn't it!

You'd get your cost per watt WAY down, and your optimal load would
tend to fbe less than peak power density and avor something in the 80%
range, and if energy use were cricital you could even crank it up to
90% in those cases.

So, efficiencies can be 90% - TODAY - if we wanted them to be by
dropping overvoltages to 1/6th their values at 60% efficiency which
cuts power density accordingly.
..
Reducing overvoltages by a factor of 6 cause fuel cell efficiencies to
increase from 60% range to 90% range on the power production side.
And efficiencies in electrolysis are 90% already.

Now reduce the cost of membranes by a factor of 200 - and you can make
them big enough to get energy density down to the point where you're
90% efficient each step and over 80% efficiency overall.


[quote:d175efbe4c]All
I was asking for was an example, I've not seen one.
[/quote:d175efbe4c]
You've got to know that the 60% efficienct systems that you are citing
easily run at 90% efficiency in electrolyzer mode, and run 90%
efficient when power densities are cranked down to 15%-20% peak
densities right?

[quote:d175efbe4c]I've seen fuzzy
references to 60% for a bare stack,
[/quote:d175efbe4c]
Its difficult to finjd papers that discuss what is common knowledge.
ANY stack that's reasonably efficient at peak load will be supremely
efficient at low loads. This is common knowledge.

[quote:d175efbe4c]but that becomes considerably less
when balance of plant etc... is taken into account.
[/quote:d175efbe4c]
True - details count. And the most important detail for high fuel
cell efficiency is current density across the membrane and the
overvoltage needed to drive it.

Very low current densities mean very low overvoltages and very high
efficiencies. Again this is plainly common knowledge, so what is your
point?

Anyone who knows anything also knows that ANY of the fuel cells that
operate at peak power density - with efficiencies of 60% or so, also
operate at 90% efficiency at power densities that are 1/6th as great.

[quote:d175efbe4c]However, I've not
seen a pointer even to that.
[/quote:d175efbe4c]
What sort of pointer are you looking for? This is common knowledge.
Increase overvoltage to increase current, and you increase power
density across the membrane - and reduce efficiency. Lower
overvoltage, the current drops, power density drops, and efficiencies
go to 90%. What trouble do you have with this?
..
[quote:d175efbe4c]The best actual PEM cell I've actually seen was considerably less than
50%, although getting efficiency figures out of manufacturers data
sheets can be quite an excercise.
[/quote:d175efbe4c]
50% at peak power density yes. But THOSE SAME FUEL CELLS may operate
at 90% efficiency at 1/5th this power level. This is common
knowledge. You've got to know it. So, why are you being obtuse about
it?

[quote:d175efbe4c]I'm not actively searching for a cell
at the moment so I'm not inclined to do the excercise for many
manufacturers out there, even the few you can get data sheets from. If,
however, there was an 80% cell I would be interested in it.
[/quote:d175efbe4c]
Any cell that operates at 60% efficiency at peak power density easily
achieves 90% efficiency in electrolysis mode and 90% efficiency in
fuel cell mode AT LOW POWER DENSITIES WITH THE ASSOCIATED LOW
OVERVOLTAGES.

[quote:d175efbe4c]it's not > 80% efficient

Yes it is. Its over 80% efficient electrolyzer and it talks about why

They claim 80%, you need quite a bit above that to meet your round trip
claim.

Yes you do - you need 90% each way to get to 81% round trip

Maybe even higher than that, I thing mentioned in my wanderings is that
convetionally Fuel cells use the lower heating value when calculating
efficiency and electrolyzers use the higher heating value. If that
holds ther's an additional nearly 15% to account for leading to a need
for on the order of 97% efficiency for each.
[/quote:d175efbe4c]
Then there's Gibbs free energy and chemical energies. haha.. Lots of
details count. But generally speaking operating at low overvoltages
increase efficiency, so those efficiencies that you quote - are for
peak power density - they get the most power at the least cost and
least weight - are dramatically improved in the same cells at lower
power densities. To over 90% - which is my point.

[quote:d175efbe4c]the shape of the power is important - it quite specifically talks
about actually building stuff and explains things in gory detail -
specifically answering the original poster's questions and supporting
nearly everything I said in response to it.

(and I don't trust the
figures they do give).

Why is that exactly? They go into detail relating the volume of gas
at STP to precise measurement of power they give. They lay everything
out in a lot of detail. What details did they get wrong?

They haven't done any measurements of how much hydrogen they actually
have. As opposed to say water vapour. I'd expect a fair amount of the
latter given the description. The also don't measure voltage drop to
see where it's occuring. They have made no attempt to determine leakage
current.

These are good points. Any idea how much these are likely to change
their efficiency estimates? PLUS or minus 2% perhaps?

At a guess 50% wouldn't surprise me.
[/quote:d175efbe4c]
Why guess when you can look at actual expeience? Fact is you're
being obtuse about my comments. Why? I don't know. You are clearly
smart enough to know that fuel cells can easily operate at 90% and
knowledgeable enough to know why it isn't reported in the literature,
and aware enough to know that the 60% efficiencies quoted in the
literature are under very specific load conditions. PEAK EFFICIENCIES
90% for these very same cells that you quote at efficiencies for at
PEAK POWER DENSITY.

Why are you trying to confuse everyone?

[quote:d175efbe4c]Finally I believe they've used the wrong figures for
determining efficiency from voltage drop even if they did have proper
figures to start with.

Please explain that. What did they get wrong specifically? Its all
there, if they made a mistake you should be able to tell me
specificially what the mistake is. I'm the one that scanned it and I
admit they may have made one I didn't see. But if you saw a specific
mistake, then it should be easy for you to say what it was shouldn't
it? But you didn't say. So, I'm asking you.

Specifically I'm concerned about their use of 1.48V for their
electrolyzing efficiency in the calculations. I think they are
including voltages other than those contributing to electrolysis and
getting artificially high efficiency figures as a result.
[/quote:d175efbe4c]
Where do you imagine these voltages are coming from and why wouldn't
it show up in their experimental apparatus?

[quote:d175efbe4c]Giving a link to a site promoting > 100%
efficient electrolysis is a VERY bad start.

First off, I didn't say anything about the site, I referenced the
paper which was quite detailed. Please show me where anyone said
anything about >100% efficiency. They didn't. They spoke of APPARENT

http://waterfuelcell.org/Peoples%20Projects.html

This isn't the paper I cited is it? haha.. NO!

It's the site you cited.
[/quote:d175efbe4c]
I looked at the paper not the cite.

[quote:d175efbe4c]Any post on a perpetual motion site will be
heavily discounted. Period.
[/quote:d175efbe4c]
The paper I cited DOES NOT claim perptual motion and DOES NOT claim
greater than 100% efficiency. It goes to great lengths to point out
efficiencies of 80% ore very high.


[quote:d175efbe4c]but you should know better.

About what precisely? These vauge dismissive comments with no
referent.

That references are judged partially on the company they keep.
[/quote:d175efbe4c]
I merely looked at a paper that came up when I did a google search -
because you wanted a paper. This one I thought covered the basics.
Apparently rather than read the paper for its content, you went and
did something I didn't do. Examine the web site it was found on until
you found a reason to discount it - however lame.

One has to wonder what is motivating you in being so obtuse.

[quote:d175efbe4c]I
wouldn't expect references to papers on flight that lead to a UFO site
[/quote:d175efbe4c]
haha.. Are you claiming this paper made claims about the paranomral
and UFOs? haha.. What a crock! What are you going to say next
about this paper? That it worships satan? lol. You're a trip Robert
you know that? haha..

[quote:d175efbe4c]to be taken highly seriously either.
[/quote:d175efbe4c]
We're talking electrolyzers in this paper. Earlier you were talking
about PEM fuel cells and the full cycle efficiency.

So, lets not get confused.

Any person knowledgeable in the art would look AT THIS PAPER and see
that they cover the basics of electrolysis construction. And that is
all you need to show that very simple systems can be very efficient at
creating gases. As you say there are details in heating value
calculation that can affect teh result. There are well known to any
undergrad chemistry student, and need not concern us here, to build a
case against this paper on that basis is ludicrous.

Now, as to your need to see support of my PEM full cycle PEAK
EFFICIENCY numbers I guess I'd refer you back to the basics. You're a
knowledgeable person - you know that the efficiencies you bandy about
are measured at PEAK POWER DENSITY. And you also know that by backing
off the power density you can get efficiencies exceeding 90% at each
step - giving greater than 80% efficiency full cycle

So what's your beef really?

You have none - but you act like you do.

Get a grip - and accept the fact. Fuel cells can store and retrieve
energy with 80% efficiency if operated at power densities that reduce
overvoltages to a minimum.


[quote:d175efbe4c]Robert

--
Posted via a free Usenet account fromhttp://www.teranews.com- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -[/quote:d175efbe4c]
 
Eeyore
Posted: Thu Jun 14, 2007 8:08 am
 
Williamknowsbest wrote:

[quote:72fddd65be]Wait a minute. Are you saying you are unaware that nearly all fuel
cells that have 50% to 60% efficiency at peak power - you are unaware
that those very same fuel cells operate at 80% to 90% efficiency at
very low power? Are you saying this? Are you saying you need a
REFERENCE for this?
[/quote:72fddd65be]
Apparently you require one to 'prove' that Varta can make a simple 2700mAh NiMH cell !

I suppose you think Varta are lying ?


[quote:72fddd65be]Wow.
[/quote:72fddd65be]
WOW indeed.

Just buy a Varta 2700mAh NiMH and check it out. On sale now - the battery you claim *CAN'T BE MADE*
!

Graham
 
Eeyore
Posted: Thu Jun 14, 2007 12:05 pm
 
Williamknowsbest wrote:

[quote:3ce850fffc]Eeyore wrote:
Williamknowsbest wrote:
Wait a minute. Are you saying you are unaware that nearly all fuel
cells that have 50% to 60% efficiency at peak power - you are unaware
that those very same fuel cells operate at 80% to 90% efficiency at
very low power? Are you saying this? Are you saying you need a
REFERENCE for this?

Apparently you require one to 'prove' that Varta can make a simple 2700mAh > NiMH cell !

I suppose you think Varta are lying ?

Wow.

WOW indeed.

Just buy a Varta 2700mAh NiMH and check it out. On sale now - the battery > you claim *CAN'T BE MADE*
!

Don't be a fool. I'm not doubting 2700 mAh AA NiMH batteries.
[/quote:3ce850fffc]
You were a few posts back.


[quote:3ce850fffc]I'm doubting that such batteries have energy densities 3x higher than
accepted figures.
[/quote:3ce850fffc]
Early NiMH AAs had a capacity of ~ 1000mAh. Which one conforms to 'accepted figures' ?


[quote:3ce850fffc]This whole issue arose from Graham's statement that the figures Honda
quoted in their EV website as being 1/3 the currently accepted figures
for NiMH batteries. Graham said that not me.
[/quote:3ce850fffc]
I never referenced Honda. You introduced them. I have no interest whatever in what they have to say on
the matter. Their work was clearly with older technology batteries.


[quote:3ce850fffc]This came from the observation that Honda needs 800 pounds of
batteries and Graham said he can get the same performance out of 160
pounds of the same kind of batteries because a) his auto design is
better than the best Honda can do, and b) he uses more modern
batteries are 3x more energy dense per kg than Honda is able to come
up with.

In response to these bold claims I asked Graham for pointers to any
literature that supports his latter contention. To which he came up
with some figures about AA NiMH batteries- which I found unconvincing
- and still do.
[/quote:3ce850fffc]
The energy density figures are a fact.

Graham
 
Don Lancaster
Posted: Thu Jun 14, 2007 12:11 pm
 
Eeyore wrote:
[quote:90bd8ff775]
Williamknowsbest wrote:


Eeyore wrote:

Williamknowsbest wrote:

Wait a minute. Are you saying you are unaware that nearly all fuel
cells that have 50% to 60% efficiency at peak power - you are unaware
that those very same fuel cells operate at 80% to 90% efficiency at
very low power? Are you saying this? Are you saying you need a
REFERENCE for this?

Apparently you require one to 'prove' that Varta can make a simple 2700mAh > NiMH cell !

I suppose you think Varta are lying ?


Wow.

WOW indeed.

Just buy a Varta 2700mAh NiMH and check it out. On sale now - the battery > you claim *CAN'T BE MADE*

!

Don't be a fool. I'm not doubting 2700 mAh AA NiMH batteries.


You were a few posts back.



I'm doubting that such batteries have energy densities 3x higher than
accepted figures.


Early NiMH AAs had a capacity of ~ 1000mAh. Which one conforms to 'accepted figures' ?



This whole issue arose from Graham's statement that the figures Honda
quoted in their EV website as being 1/3 the currently accepted figures
for NiMH batteries. Graham said that not me.


I never referenced Honda. You introduced them. I have no interest whatever in what they have to say on
the matter. Their work was clearly with older technology batteries.



This came from the observation that Honda needs 800 pounds of
batteries and Graham said he can get the same performance out of 160
pounds of the same kind of batteries because a) his auto design is
better than the best Honda can do, and b) he uses more modern
batteries are 3x more energy dense per kg than Honda is able to come
up with.

In response to these bold claims I asked Graham for pointers to any
literature that supports his latter contention. To which he came up
with some figures about AA NiMH batteries- which I found unconvincing
- and still do.


The energy density figures are a fact.

Graham

There was a fundamental breakthrough in NiMh and NiCad a year or two[/quote:90bd8ff775]
back in which they learned to control three outer shell electrons
instead of just two.

Which gave a theoretical 50% bump to the maximum energy density.

It was basically a question of learning how to stabilize.

--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: don@tinaja.com

Please visit my GURU's LAIR web site at http://www.tinaja.com
 
Eeyore
Posted: Thu Jun 14, 2007 12:54 pm
 
Don Lancaster wrote:

[quote:2abb2abcea]Eeyore wrote:
Williamknowsbest wrote:

In response to these bold claims I asked Graham for pointers to any
literature that supports his latter contention. To which he came up
with some figures about AA NiMH batteries- which I found unconvincing
- and still do.

The energy density figures are a fact.

Graham

There was a fundamental breakthrough in NiMh and NiCad a year or two
back in which they learned to control three outer shell electrons
instead of just two.

Which gave a theoretical 50% bump to the maximum energy density.

It was basically a question of learning how to stabilize.
[/quote:2abb2abcea]
That would explain the step increase in capacity.

Previous advances are I imagine just a result of improved manufacture / process refinement.

There are also now these NiMHs with low self-discharge too, good for about 80% capacity remaining after one
year 'on the shelf'.

Graham
 
Williamknowsbest
Posted: Fri Jun 15, 2007 2:24 am
 
On Jun 14, 1:05 pm, Eeyore <rabbitsfriendsandrelati...@hotmail.com>
wrote:
[quote:0ba93d4311]Williamknowsbest wrote:
Eeyore wrote:
Williamknowsbest wrote:
Wait a minute. Are you saying you are unaware that nearly all fuel
cells that have 50% to 60% efficiency at peak power - you are unaware
that those very same fuel cells operate at 80% to 90% efficiency at
very low power? Are you saying this? Are you saying you need a
REFERENCE for this?

Apparently you require one to 'prove' that Varta can make a simple 2700mAh > NiMH cell !

I suppose you think Varta are lying ?

Wow.

WOW indeed.

Just buy a Varta 2700mAh NiMH and check it out. On sale now - the battery > you claim *CAN'T BE MADE*
!

Don't be a fool. I'm not doubting 2700 mAh AA NiMH batteries.

You were a few posts back.
[/quote:0ba93d4311]

No I doubted your assertion that 2700 mAh proved that Honda's figures
were off by a factor of three.

[quote:0ba93d4311]
I'm doubting that such batteries have energy densities 3x higher than
accepted figures.

Early NiMH AAs had a capacity of ~ 1000mAh. Which one conforms to 'accepted figures' ?
[/quote:0ba93d4311]
I tend to think Honda's experience with EVs is to be trusted more than
your gut instincts and poor math skills. haha.. I know that's a
shocker to you, and a blow to your inflated ego. But that's my
position, and you haven't said anything to change it. Though I'm
still talking to you.
..
[quote:0ba93d4311]This whole issue arose from Graham's statement that the figures Honda
quoted in their EV website as being 1/3 the currently accepted figures
for NiMH batteries. Graham said that not me.

I never referenced Honda. You introduced them.
[/quote:0ba93d4311]
That's right. I pointed to the experience of Honda as a reasonable
expectation. You said you could go 100 miles or so with 160 pounds of
NiMH batteries and I said Honda can go about 100 miles with about 800
pounds of NiMH batteries - and doubted your figures. In response you
said you were better at building cars than Honda and their engineers
didn't know a damn thing about batteries and to prove it you did a
calculation with a AA battery you bought which proved their numbers
were 1/3 the value you got and they were all wet or using old data.

In response I asked you to show me any literature anywhere that touted
a 3 fold increase in the energy density of NiMH -

At that point you launched into a vituperous personal attack of me and
interestingly enough academics and peer reviewed literature. haha..

At that point I marked you off as a self-important nutjob.

But I'm still interested to see what you're going on about... lol

[quote:0ba93d4311]I have no interest whatever in what they have to say on
the matter.
[/quote:0ba93d4311]
Oh no, I agree, your abilities and experience in building automobiles
far surpases theirs! HAHAHAHAHAHA!

[quote:0ba93d4311]Their work was clearly with older technology batteries.
[/quote:0ba93d4311]
That's not clear at all. More likely you got your numbers wrong and
they're using the very same batteries - except they're really
engineers who know what they're doing and you're just a guy with a AA
battery and the package it came in doing your maths wrong.

[quote:0ba93d4311]This came from the observation that Honda needs 800 pounds of
batteries and Graham said he can get the same performance out of 160
pounds of the same kind of batteries because a) his auto design is
better than the best Honda can do, and b) he uses more modern
batteries are 3x more energy dense per kg than Honda is able to come
up with.

In response to these bold claims I asked Graham for pointers to any
literature that supports his latter contention. To which he came up
with some figures about AA NiMH batteries- which I found unconvincing
- and still do.

The energy density figures are a fact.
[/quote:0ba93d4311]
Please point to anything anywhere that says that NiMH is 3x more
energy dense today than it was a few years ago, and prove that Honda
doesn't know what they're doing.

[quote:0ba93d4311]Graham- Hide quoted text -

- Show quoted text -[/quote:0ba93d4311]
 
 
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