Odyssey Battery-Jerry Springer

Rob Cherney wrote:

I did a lot of research on batteries and settled on the Odyssey when a
replacement was needed for Long-EZ N271J. I put a PC-925 (27 A-h) in
her back in February. So far, so good.

I use a sealed lead-acid lawn tractor battery from the local
automobile parts store in my Long EZ -- about $25 as I recall. I swap
it out every 2 to 3 years. It cranks in 20 degree F temps and I've
never had one fail. I prefer this to buying an expensive battery and
hoping it will last 4+ years. Too heavy? Not for me. In fact I have
two 8 lb lead shot bags straddling the thing.

David O -- http://www.AirplaneZone.com

On Sun, 31 Aug 2003 11:17:54 -0400, David O
wrote:


Rob Cherney wrote:

I did a lot of research on batteries and settled on the Odyssey when a
replacement was needed for Long-EZ N271J. I put a PC-925 (27 A-h) in
her back in February. So far, so good.

I use a sealed lead-acid lawn tractor battery from the local
automobile parts store in my Long EZ -- about $25 as I recall. I swap
it out every 2 to 3 years. It cranks in 20 degree F temps and I've
never had one fail. I prefer this to buying an expensive battery and
hoping it will last 4+ years.

Trading lifetime for cost works when you have easy access to the battery to
swap it out (like Long-EZs I've seen) but it's a bear when it's hard to
access the battery. The gel-cell in my Fly Baby is mounted forward of the
instrument panel, flush with the cockpit floor, underneath a big box
containing all the avionics and electrical system paraphernalia (circuit
breakers, gauges, etc.). Getting to the box requires jackknifing as far as
the instrument panel will let me or almost standing on my head hanging over
the cockpit sidewalls.

The box, as it exists now, cannot be removed without physically dismounting
the transponder (hardwired with no connectors). I can, barely, move it far
enough to get the battery out from underneath.

Needless to say, this is NOT a process I like to do very often. I'll
gladly pay $25 or $50 more for a battery I only have to replace every four
years instead of every two.

Now, if only I could find one... :-)

Ron "Standing on my head next weekend" Wanttaja

Ron Wanttaja wrote:

snip

Now, if only I could find one... :-)

Agreed on all points, including the last.

David O -- http://www.AirplaneZone.com

Rob Cherney wrote in message . ..
On Sat, 30 Aug 2003 23:32:20 GMT, (Badwater
Bill) wrote:

Another goofy thing about the Odyssey is that you can't recharge it
using a trickle charger. Less than 1.25 Amps won't put all the energy
back into the battery. You have to use a 10 Amp charger to get back
to full energy.

From their data, it looks like the charge efficiency sharply decreases
below 0.1C (1C = rated A-h @ 10h discharge rate). This is 1.6A for
your battery. Note that this only applies to a fully discharged
battery.

Anybody know the chemistry behind that? I don't get
it. Lead peroxide is lead peroxide. When you drive the sulfate off
the lead atom and reattach an oxygen, what the hell difference does it
make how fast you do it (high Amps)?

Hawker doesn't say specifically, but reading between the lines it
looks like it could be a function of the small amount of tin that's
added to the lead in the plates. This is done to increase service
life for deep-discharge applications. Don't ask me about tin
chemistry, though. I'm an electronics weenie.

The only thing I can think of is
that the battery itself has an internal resistance of 7 Ohms so the
higher the current, the higher the temperature of the battery itself.
And, as you all know, for every 10 degrees Centigrade, the chemical
reactivity rate coefficient doubles.

Two things:

The internal resistance is 7 milliohms.

The primary aging mechanism for these batteries is corrosion of the
positive electrode grid. For this particular mechanism, the reaction
doubles every 8 °C, not 10° C as one would expect.

So, the rate constant will be
higher for the charge cycle on a hot battery. They say you can
completely recharge this baby in 2 hours if you use 10 Amps. I'm
thinking that it heats up...that's why!

Yep, and that's not unique to this particular battery.

Actually, Odyssey says the battery can be recharged in as little as 20
minutes, assuming you have a charger that's beefy enough (3.5C= 56 A).
At this rate, the internal temperature will rise about 20 °C and will
peak about the time charging current starts decreasing (assumes the
recommended voltage-limited constant-current charging).

For a 2-hour charge, the expected temperature rise will be only about
10 °C.

By the way, my information came from http://www.hepi.com/papers.htm.
I pretty sure the Odyssey battery is an evolution of the Cyclon and
Genesis batteries that are mentioned in the papers.

Lastly...

I did a lot of research on batteries and settled on the Odyssey when a
replacement was needed for Long-EZ N271J. I put a PC-925 (27 A-h) in
her back in February. So far, so good.


Rob-
------------------------------------------------------------------
Robert Cherney e-mail: rcherney(at)comcast(dot)net


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I've used an Odyssey PC 925 in my RV-4 for 1 1/2 years and it sits on
its SIDE, in the same place the worthless Gel-Cel fit,and cranks with
seemingly no end. It survived me learning hot-starts last summer just
fine.
NO MORE Gel-Cels for me !! I put the one from the RV-4 in my antique
Farmall runway mower. Most expensive mower battery in the
neighborhood!

Bob Olds RV-4 , N1191X
Charleston,Arkansas



************************************************** *****************************

************************************************* *******************************


I've used an Odyssey PC 925 in my RV-4 for 1 1/2 years and it sits on
its SIDE, in the same place the worthless Gel-Cel fit,and cranks with
seemingly no end. It survived me learning hot-starts last summer just
fine.
NO MORE Gel-Cels for me !! I put the one from the RV-4 in my antique
Farmall runway mower. Most expensive mower battery in the
neighborhood!

Bob Olds RV-4 , N1191X
Charleston,Arkansas



************************************************* ******************************

Alright. I agree. There is nothing like a fine quality piece of
equipment that you can rely upon.

I had a 35 Amp-hr Gel-cell in my RV-6. It was expensive, it weighed a
lot and it crapped out on me when it got cold. I have no idea why Van
recommends it. I still have access to that airplane and I flew it
this last weekend. I was in Utah this morning at 37 degrees F and
worried as hell about it cranking. But, after I put the Lightspeed
ignition system in that thing and went to a mult-vis oil for the cold,
it cranks fine.

An old timer told me how to start that thing about three years ago.
His name is Paul Muskat and he's an old examiner who retired many
years ago, plus he's an A & P. He passed this on to me and I swear to
God it's the answer to the starting problems I had on the RV-6. In
fact I'm not so sure I needed to buy and instal that Lightspeed
ignition after I changed the way I started--due to Paul. Here's what
he said:

Prime this thing with about 4 pumps of the prime plunger. Of course
wait until it stops wheezing each time so you know you are getting a
good shot of fuel.

MAKE SURE YOUR MAG SWITCHES ARE OFF.

Go around and pull that O-320 through all four cylinders

Then get in and crank it.

I did that this morning and it hit on the first cylinder. Of course
Claus's plasma ignition system is about like starting an electric
motor. If you do the ABOVE, then crack the throttle and hit the
starter, with the retardation and advancement of timing that the
Lightspeed ignition gives you, the prop just starts turning, you drop
out the starter and it continues to turn like an electric motor. I've
never seen anything like it in a Lycoming.

What a NOVEL idea, change the timing as needed just like you do in a
car. How innovative. How modern. Christ, sometimes I think we are
in the stone age with Lycoming and Continental. They should have done
this years ago. It works great guys. Hell, 4 D-Cell batteries would
start that RV-6 now.

BWB

An old timer told me how to start that thing about three years ago.
His name is Paul Muskat and he's an old examiner who retired many
years ago, plus he's an A & P. He passed this on to me and I swear to
God it's the answer to the starting problems I had on the RV-6. In
fact I'm not so sure I needed to buy and instal that Lightspeed
ignition after I changed the way I started--due to Paul. Here's what
he said:

Lightspeed ignition, NOT required, *IF* you follow the steps
that were recommended to you below.

Prime this thing with about 4 pumps of the prime plunger. Of course
wait until it stops wheezing each time so you know you are getting a
good shot of fuel.

MAKE SURE YOUR MAG SWITCHES ARE OFF.

Yep - absolutely key part of the process.

Go around and pull that O-320 through all four cylinders

Not necessary, *IF* you can crank with... MAGS OFF.

Then get in and crank it.

I did that this morning and it hit on the first cylinder.

BWB

Yep.
What was happening...
you were *FROSTING* the sparkplugs.

Once ICED...
Ya either wait for the ice to melt or remove it.

If you don't believe it....
pull a plug when the engine absolutely won't start.
Check for ICE shorting across the electrodes!
It will be there in mass quantities !!!!!!

I learned this the hard way, as a 16 year old teenager.
I had a car that would not start below 32 degrees.
Ditto for a Cessna 175.
Above 32, both would always start on the first lick.

Below 32 degrees...
Both engines required FUEL to be in the cylinders BEFORE
turning on the ignition or the hot spark would cause ICE
to form across the sparkplug electrodes.

In SOME, but not all engines...
The hot spark causes the cold moist air WITHOUT FUEL
in the cylinder to CONDENSE across the electrodes as
ice... if it's 32 or colder. Once shorted in this manner,
your screwed until it warms up or you remove the ice.

Trust me on this one. g


Barnyard BOb -- believe it or not

On Thu, 04 Sep 2003 03:21:18 -0500, Barnyard BOb --
wrote:



An old timer told me how to start that thing about three years ago.
His name is Paul Muskat and he's an old examiner who retired many
years ago, plus he's an A & P. He passed this on to me and I swear to
God it's the answer to the starting problems I had on the RV-6. In
fact I'm not so sure I needed to buy and instal that Lightspeed
ignition after I changed the way I started--due to Paul. Here's what
he said:

Lightspeed ignition, NOT required, *IF* you follow the steps
that were recommended to you below.

I know that now and agree. I jumped the gun on that one. I should
have known how to start that engine without spending a grand on that
fancy ignition. But I didn't.


Yep.
What was happening...
you were *FROSTING* the sparkplugs.

Once ICED...
Ya either wait for the ice to melt or remove it.

If you don't believe it....
pull a plug when the engine absolutely won't start.
Check for ICE shorting across the electrodes!
It will be there in mass quantities !!!!!!

Interesting. I don't quite see the physics of that. Must have
something to do with the adiabatic expansion of air in the cylinder
causing the temp to drop way down.


I learned this the hard way, as a 16 year old teenager.
I had a car that would not start below 32 degrees.
Ditto for a Cessna 175.
Above 32, both would always start on the first lick.

Below 32 degrees...
Both engines required FUEL to be in the cylinders BEFORE
turning on the ignition or the hot spark would cause ICE
to form across the sparkplug electrodes.

What's the difference between pulling it through by hand or cranking
it? The same thing is happening except that you don't get a spark?


In SOME, but not all engines...
The hot spark causes the cold moist air WITHOUT FUEL
in the cylinder to CONDENSE across the electrodes as
ice... if it's 32 or colder.

Why? How?

Once shorted in this manner,
your screwed until it warms up or you remove the ice.

Trust me on this one. g

Nature is amazing in it's own right. Being a physicist I know that
the truth is much stranger than fiction, but I don't see this one for
some reason. I'm not saying I don't believe it. I'm just saying I
can't see the mechanism.

Bill


Barnyard BOb -- believe it or not