I suspect that this has already been discussed, but since I don't have
access to the archives, I beg your indulgence...

We have new, L16H batteries in our 880AH house bank, flooded cell. In a
perfect world to make them last longest, I know that they'd never be
allowed to drop below 100% capacity - but then, what's the point of
having a battery?

I also know that running them down to 20% on a regular basis will make
for a short life span.

So, the question (well, maybe two) is:

What is the recommended, real-world cycle? That is, how low do you
take your flooded batteries on a regular basis? Related, is there a
readily available source for information on the numbers of cycles to a
given percentage of discharge in a battery life span? I.e., 500
cycles to 50% and back to 100% but only 100 cycles to 20% and up to
75%, or the like (recognizing that these numbers have no relation to
any battery made)?

Second, what do those of you with flooded cells, not connected to the
shore power all the time (that is, full-time cruisers or rarely
connected to the utility-based power cord) have as a practice? What
charge regime, and how, do you observe? Never below X%, seldom above
Y%/Always more than Y% of capacity?

We have a variety of charging sources and differing loads which makes
for days when we may see close to 50%, and days when it never leaves
"full" - and since we can't "force" "full" reasonably, we want to make
sure we're not unreasonably asking for our batteries performance.

Knowledgeable assistance appreciated, and your practice, whether
empirical or just "is" would also be appreciated.

Thanks.

L8R

Skip (Gundlach) and crew, lying Lucaya, over (what else??) wifi among
the 14 available open sites we can see

Morgan 461 #2 St. Thomas USVI
SV Flying Pig KI4MPC
See our galleries at www.justpickone.org/skip/gallery !
Follow us at http://groups.yahoo.com/group/TheFlyingPigLog
and/or http://groups.google.com/group/flyingpiglog

"And then again, when you sit at the helm of your little ship on a
clear
night, and gaze at the countless stars overhead, and realize that you
are
quite alone on a wide, wide sea, it is apt to occur to you that in the
general scheme of things you are merely an insignificant speck on the
surface of the ocean; and are not nearly so important or as
self-sufficient
as you thought you were. Which is an exceedingly wholesome thought,
and one
that may effect a permanent change in your deportment that will be
greatly
appreciated by your friends."- James S. Pitkin

"Flying Pig" wrote in news:gsb96s$bp9$1
@news.motzarella.org:

What is the recommended, real-world cycle? That is, how low do you
t

50%.....run them from 50% to 95% charge. Mine are 8 years old in an old
stepvan running like that. The shop runs on them all day. L16H is a great
power source very cheap!

USE ONLY PURE DISTILLED, NOT DEMINERALIZED, WATER! The dissolved iron and
calcium in common water simply consume the acid and plate the lead with
crap. There's plenty of iron and other odd metals built into the plates to
do that for you....especially in a battery THIS cheap. No need to add to
the problem not using real distilled pure water to top off at REGULAR
intervals....not like most boaters when the lights get dim...(c;]



--
================================================== ==========
Larry

I've decided to worship Thor. My god has a hammer and isn't
afraid to use it. Your god is a pacifist who got nailed to a
tree.

Any questions?

On 17 apr, 23:16, Larry wrote:

USE ONLY PURE DISTILLED, NOT DEMINERALIZED, WATER! *

I use water produced by my watermaker from drinking
water that also was produced by my watermaker.
When I put my TDS meter in it, it shows less than 100 ppm.
What do you think of that?

Len.

On Fri, 17 Apr 2009 21:10:59 -0400, "Flying Pig"
wrote:

I suspect that this has already been discussed, but since I don't have
access to the archives, I beg your indulgence...

We have new, L16H batteries in our 880AH house bank, flooded cell. In a
perfect world to make them last longest, I know that they'd never be
allowed to drop below 100% capacity - but then, what's the point of
having a battery?

I also know that running them down to 20% on a regular basis will make
for a short life span.

So, the question (well, maybe two) is:

What is the recommended, real-world cycle? That is, how low do you
take your flooded batteries on a regular basis? Related, is there a
readily available source for information on the numbers of cycles to a
given percentage of discharge in a battery life span? I.e., 500
cycles to 50% and back to 100% but only 100 cycles to 20% and up to
75%, or the like (recognizing that these numbers have no relation to
any battery made)?

Second, what do those of you with flooded cells, not connected to the
shore power all the time (that is, full-time cruisers or rarely
connected to the utility-based power cord) have as a practice? What
charge regime, and how, do you observe? Never below X%, seldom above
Y%/Always more than Y% of capacity?

We have a variety of charging sources and differing loads which makes
for days when we may see close to 50%, and days when it never leaves
"full" - and since we can't "force" "full" reasonably, we want to make
sure we're not unreasonably asking for our batteries performance.

Knowledgeable assistance appreciated, and your practice, whether
empirical or just "is" would also be appreciated.

Thanks.

L8R


Batteries should never be run below 50% if you want decent life from
them. Further, no battery likes to remain below 100% for extended
periods. They should be recharged promptly after being run down.
Similarly, batteries not being used should be kept at or very near
fully charged at all times.

You can, of course vary from this, but it will be at the expense of
battery life and capacity.

On Fri, 17 Apr 2009 21:10:59 -0400, "Flying Pig"
wrote:

What is the recommended, real-world cycle? That is, how low do you
take your flooded batteries on a regular basis? Related, is there a
readily available source for information on the numbers of cycles to a
given percentage of discharge in a battery life span? I.e., 500
cycles to 50% and back to 100% but only 100 cycles to 20% and up to
75%, or the like (recognizing that these numbers have no relation to
any battery made)?

There is some pretty good information in this deep cycle battery FAQ:

http://www.windsun.com/Batteries/Battery_FAQ.htm

50% depth-of-discharge is a good working average with 80% an absolute
maximum. Our house bank consists of 4 Trojan golf cart batteries and
we get about 3 years out of them adhering closely to those guidelines.

I have seen figures quoted that regular cycling to 80% DOD will cut
battery life in half.

Len wrote in news:9eaf72c3-93ef-4f82-a35f-
:

On 17 apr, 23:16, Larry wrote:

USE ONLY PURE DISTILLED, NOT DEMINERALIZED, WATER! *

I use water produced by my watermaker from drinking
water that also was produced by my watermaker.
When I put my TDS meter in it, it shows less than 100 ppm.
What do you think of that?

Len.


I'm not really sure RO water is chemically pure enough for battery
chemistry. Anything left through the membrane that reacts with acid will
eat the acid in the battery. Distilled water run through an activated
carbon column is so pure here it will not conduct electricity. Water is an
insulator. At a UHF TV station that's using water-cooled klystrons,
there's 18,500VDC on the collector boiling gallons/min of distilled water.
Current is minimal.

It would seem to me RO would pass dissolved metals the battery doesn't want
poured into it....but it's better than tap water, I suppose.

--
================================================== ==========
Larry

I've decided to worship Thor. My god has a hammer and isn't
afraid to use it. Your god is a pacifist who got nailed to a
tree.

Any questions?

"Flying Pig" wrote in message
...
I suspect that this has already been discussed, but since I don't have
access to the archives, I beg your indulgence...

We have new, L16H batteries in our 880AH house bank, flooded cell. In a
perfect world to make them last longest, I know that they'd never be
allowed to drop below 100% capacity - but then, what's the point of
having a battery?

I also know that running them down to 20% on a regular basis will make
for a short life span.

So, the question (well, maybe two) is:

What is the recommended, real-world cycle? That is, how low do you
take your flooded batteries on a regular basis? Related, is there a
readily available source for information on the numbers of cycles to a
given percentage of discharge in a battery life span? I.e., 500
cycles to 50% and back to 100% but only 100 cycles to 20% and up to
75%, or the like (recognizing that these numbers have no relation to
any battery made)?

Second, what do those of you with flooded cells, not connected to the
shore power all the time (that is, full-time cruisers or rarely
connected to the utility-based power cord) have as a practice? What
charge regime, and how, do you observe? Never below X%, seldom above
Y%/Always more than Y% of capacity?

We have a variety of charging sources and differing loads which makes
for days when we may see close to 50%, and days when it never leaves
"full" - and since we can't "force" "full" reasonably, we want to make
sure we're not unreasonably asking for our batteries performance.

Knowledgeable assistance appreciated, and your practice, whether
empirical or just "is" would also be appreciated.

Thanks.

L8R

Skip (Gundlach) and crew, lying Lucaya, over (what else??) wifi among
the 14 available open sites we can see

Morgan 461 #2 St. Thomas USVI
SV Flying Pig KI4MPC
See our galleries at www.justpickone.org/skip/gallery !
Follow us at http://groups.yahoo.com/group/TheFlyingPigLog
and/or http://groups.google.com/group/flyingpiglog

"And then again, when you sit at the helm of your little ship on a
clear
night, and gaze at the countless stars overhead, and realize that you
are
quite alone on a wide, wide sea, it is apt to occur to you that in the
general scheme of things you are merely an insignificant speck on the
surface of the ocean; and are not nearly so important or as
self-sufficient
as you thought you were. Which is an exceedingly wholesome thought,
and one
that may effect a permanent change in your deportment that will be
greatly
appreciated by your friends."- James S. Pitkin





You have a big problem, Skippy. The problem is you are trying to run what
amounts to the average size house ashore on batteries. Considering your
total power usage you need a battery bank of at least 20 (yes, I said
TWENTY) of those Trojan deep cycle six-volt batteries. Then you need a
separate battery bank of at least 2 heavy duty cranking batteries for your
starter.

You should do either of three things.

1) continue to be an energy hog and plan on running your diesel with heavy
duty alternator for at least 8 hours a day to properly charge the above
suggested battery bank.
2) invest in an 8KW diesel variable output genset and run it 24/7 and reduce
the size of the suggested battery bank by a factor of five.
3) get rid of 80% of the crap in your boat that runs on electricity that you
don't need anyway and start acting like a sensible cruiser and have a
battery bank of 4 Trojans plus two starter batteries and charge them using
photovoltaics (400 watts worth) plus wind generator and stick to using no
more electricity per day than these input.



Wilbur Hubbard

In article ,
says...
Len wrote in news:9eaf72c3-93ef-4f82-a35f-
:

On 17 apr, 23:16, Larry wrote:

USE ONLY PURE DISTILLED, NOT DEMINERALIZED, WATER! *

I use water produced by my watermaker from drinking
water that also was produced by my watermaker.
When I put my TDS meter in it, it shows less than 100 ppm.
What do you think of that?

Len.


I'm not really sure RO water is chemically pure enough for battery
chemistry. Anything left through the membrane that reacts with acid will
eat the acid in the battery. Distilled water run through an activated
carbon column is so pure here it will not conduct electricity. Water is an
insulator. At a UHF TV station that's using water-cooled klystrons,
there's 18,500VDC on the collector boiling gallons/min of distilled water..
Current is minimal.

It would seem to me RO would pass dissolved metals the battery doesn't want
poured into it....but it's better than tap water, I suppose.

RO filters DO NOT pass dissolved metals. If they did they would be of
little use in generating fresh water from sea water.

Unless you use a laboratory-quality still, RO water will be as pure
as distilled water if the filter is operated properly.


Mark Borgerson

"Mark Borgerson" wrote in message
g...
RO filters DO NOT pass dissolved metals. If they did they would be of
little use in generating fresh water from sea water.

Unless you use a laboratory-quality still, RO water will be as pure
as distilled water if the filter is operated properly.


Mark Borgerson



WRONG! Even the best membranes may pass up to 5% of heavy metal ions.

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TFX-46WM6V7-1R&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&vie w=c&_acct=C000050221&_version=1&_urlVersion=0&_use rid=10&md5=aabc45cb84f81de69db133da6e5cf12c

This is far more than proper distilled water using heat and condensation.

Wilbur Hubbard

In article s.com,
llid says...
"Mark Borgerson" wrote in message
g...
RO filters DO NOT pass dissolved metals. If they did they would be of
little use in generating fresh water from sea water.

Unless you use a laboratory-quality still, RO water will be as pure
as distilled water if the filter is operated properly.


Mark Borgerson



WRONG! Even the best membranes may pass up to 5% of heavy metal ions.

I agree. I overstated the efficiency of RO filters. The efficiency
of RO filters depends a lot on the type of filter, the ionization state
of the metals and the feed pressure.

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6TFX-46WM6V7-1R&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&vie w=c&_acct=C000050221&_version=1&_urlVersion=0&_use rid=10&md5=aabc45cb84f81de69db133da6e5cf12c


To quote from this abstract:

"An experimental investigation was conducted to study the performance
of an aromatic polyamide (ES 20) ultra-low-pressure reverse osmosis
membrane (ULPROM) for separating divalent (Cu2+, Ni2+) and hexavalent
(Cr6+) heavy metals from bulk solution. The influence of operating
pressure, feed concentration, pH, and effect of other ions (Ca2+ and Mg2
+) on the ULPROM performance was studied. The investigation was
conducted for synthetic wastewater and wastewater from the heavy metal
industry. Experimental results show that the rejection increases with
increasing feed pressure, it is dependent on feed pH and is higher at
higher pH. Increasing concentration of other ions slightly decreased the
rejection of heavy metals. Generally, rejection of heavy metal is found
to be greater than 95% for the ULPROM tested, which suggests the
suitability of such membranes for industrial application for recovery of
heavy metal and reclaiming wastewater."

These ultra-low pressure filters are not the same as those used to
purify drinking water and the reference isn't talking about
making drinking water.

If you are purifying seawater for drinking, heavy metals are not
generally a problem, since they are generally in the parts per
million range or less in seawater.


This is far more than proper distilled water using heat and condensation.

Neither RO filters nor distillation are particularly effective in
removing metal ions if you then use metal pipes or containers for the
reulting water.

To get lab quality water generally requires double distillation
and deionization.

For drinking water made from seawater, RO filters may result in
a few parts per thousand of sodium and chlorine and a few hundred
parts per billion of heavier metals. This is probably comparable
to still that you will find on a boat---but the RO filter will
be a lot more energy efficient.


Mark Borgerson