Batteries
from the
Sailnet
Tayana List
How long lasting are the sealed lead-acid batteries? Are there special precautions when recharging? I have a bank of golf cart batteries and a Heavy Duty Starter (used only for starting). They are both under the quarter berth, which makes it a pain to check them. It means taking off all the accumulated junk, cushions, partially finished projects, then lifting off the mattress, the boards, and finally getting to the batteries. On a few occasions, I just happened to work up the energy to do all this at a point when the water was dangerously low, but still above the plates.
BTW, I was just looking at an Island Packet
and saw that they have a really sturdy method of storage of batteries. They
have a sturdy compartmentalized tray, with built-in heavy steel rods in the top
that retain the batteries even in the event of complete rollover. In that
instance, they use sealed Gel batteries, so they don't have to worry about
fluid levels. Of course, since the Gel batteries have a different resting
voltage, they can't easily be mixed with lead acid batteries (although I think
that Balmar's smart regulator can be set for a variety of combinations of
batteries?).
Harvey
J. Karten May
2001
__________________________________________________________________________________
The ones I am talking about are not
just sealed lead acid batteries, as in "maintenance free" batteries.
Each cell in the Optima batteries (www.optimabatteries.com)
is wound in a cylinder in such a way that it is stronger and more efficient.
Check the web site to learn about the engineering, but the practical result is
that you get the best of both conventional and gel (or AGM) batteries. Exide
has just come out with something similar, but I have had no recommendation on
them and their web site (www.exideworld.com ) is pretty
unhelpful. Again, I have no first hand knowledge about these yet. They were
recommended to me by Dick Simons, who is considered by many to be the best
marine electrician in San Diego.
Based on their specs, you would not need to worry about special charging as you do with gels and AGM’s. They can tolerate charging voltages up to 15v, well above the 14.4 you would use with your golf carts. Obviously, with a maximum of 15v you would take them off line when you equalize your house bank, but you would probably want to do that any way as there is generally no need to equalize a starting battery. The main advantage is their low self-discharge rate of >1% a month. Even gels are about 3% a month.
Gels also have a different max charging
voltage, 14.1 volts, so the conventional wisdom against mixing battery
chemistries still makes sense. Even if Balmar makes a regulator that can
handle two types of batteries in one system, you need to be careful that
your other charging sources can as well. Both the shore power charger and the
solar and/or wind generator regulator would have to be set for the battery type
with the lowest charging voltage, which would increase charging time for the
other.
Kent S/V Que Tal T-37 #165 May
2001
__________________________________________________________________________________
Practical
Sailor did a review of these in Volume 26 #20 Oct. 15, 2000.
John
Reynolds May
2001
__________________________________________________________________________________
I thought I would share a great source for
large battery cable wire.
During our new electric windlass
install process, we searched for a reasonably priced source and found one. I
couldn't believe the price per foot vs. the other sources we had found. The
cheapest we found, other than this source, was Jamestown Distributor at around
$4 something per foot for 2/0 wire.
We ended up paying about $1.60 per
foot (we purchased 42' pos,neg) for 2/0 wire!! It appears to be the same stuff
you would buy at a marine store; multi-strand tin coated copper, etc. It looks
the same except for the coating which is not shinny like the other stuff. We
paid $1.60 per foot, but the price may be cheaper if their 'cut stock' they
have on hand meets your needs. Ours was cut to order. A neighbor here at out
dock paid $1.40 per foot for 2/0 because they purchased the cut stock/product
that was available at the distributor.
We purchased the wire from
Anixter. (708) 597-7110. The general website is http://anixter.com/
It is a very 'deep site', so the
following link narrows it down and will get you into the 'big electrical wire
area'.
http://onlinecatalog.anixter.com/catalog/SearchResultsServlet?QUERY=KEYWORD-SEARCH&KEYWORD=Prestolite
The part #s for 2/0; Prestolite,
5MF-2021-EPDM and 5MF-2021-EPDM-03-HYS.
Walter SOLTARA September 2002
__________________________________________________________________________________
Subject: Charging different size battery
banks
When charging a bank of 4 six-volt
batteries with a 3-stage regulator (batteries drawn down 150 amp hours),
the voltage will start off around 13.9, decrease a little as they begin to
charge, and then slowly ramp up to 14.4 VDC. The charger then holds this
voltage and the amps begin to drop off.
When the amps go down to 10% of the original charging amps, the charger
drops the voltage back to 13.2. When the batteries are full (which only happens
when motoring a long time), the charger still holds float - 13.2 VDC. This
voltage is the same voltage used by 110 VAC battery chargers for long periods
of time. This can not only extend battery life but also diminish the
amount of water needed during maintenance. In fact, it may well be in many
cases that excessive water loss due to bubbling of the electrolyte at 14.4 VDC
is a primary cause of premature battery failure. The above only applies to my 450 amp-hour
battery bank.
I have a 225 amp-hour bank of 2 six-volt batteries
that reaches 14.4 volts in just minutes and then the amps start ramping down
immediately. The original 55-amp alternator that came with my boat will charge
this bank as fast as my 120-amp alternator. Small battery bank = small amps to
achieve 14.4 VDC. My six Surrette 6-volt batteries lasted 8 years before
a lightning strike put long, half-inch wide cracks in the top of 3 of the
batteries. I replaced the batteries even
though the batteries still performed just fine. My four Rolls 6-volt
batteries only lasted 7 years before one failed. I now use the GC-2 6-volt batteries from
West ($99 each) that are a direct replacement for the Rolls size-wise, although
10 amp-hours less. The problem with battery banks is that when
one goes, you need to replace all batteries in that bank. Therefore, I
agree that sometimes cheaper can be better. And standard golf-cart batteries
have the exact same size and post configuration as the West GC-2's. Changing
out batteries is easy if the new ones don't require changing battery
connectors or lengthening battery wires.
Wayne Strausbaugh V-42 C/C RESTLESS October 2002
__________________________________________________________________________________
Peace & Quiet has three 4D
lead-acid batteries, 120 amp-hours each, set up into two banks - a single
battery in one bank & 2 on the other. I am curious as to what methods other
owners use to determine when it's time to charge. The three methods that I have
available now are: 1) Estimate approximate usage per day of devices (not very
accurate) 2) Use a hydrometer to measure specific gravity (a lot of trouble) 3)
Measure the voltage of the bank with the analog voltmeter built into the
electrical panel (how accurate is this?).
I know that there are devices available that monitor the banks such as
those made by Ample but am interested in a lower tech method. Any thoughts?
Alan Jett March
2003
__________________________________________________________________________________
Subject: battery monitoring
I had an E-meter on my NorSea 27 and really
liked it. I spent most of today installing a link 20 (double bank E-meter) on
my new Tayana. Monitoring the engine start battery is probably not necessary so
the E-meter (now known as the Link 10) would have probably been adequate for my
purposes.
It is really difficult to estimate power
usage. I got a much better idea of our power use patterns after I installed the
E-meter and watched it for a few weekends of cruising. It keeps a running total
on the amp-hours you have drawn out of the bank. It also tells you how much is
being drawn at any point in time. It can be a real shock to see how the
combination of the fridge, anchor light, the light someone forgot to turn out
in the head, stove solenoid, stereo, etc. add up to a major drain. Eventually,
I got good enough at it that I could tell what loads were on by the amperage
being drawn. The kids have never figured out how I knew they had left the light
in the head on. They think I’m psychic.
The meter tells you more than when it is
time to charge the batteries. It also tells you when its time to stop charging.
I have always found myself wanting to turn the engine off as soon as possible.
The meter keeps you honest and lets you know when you have the bank 90%
charged.
Friends who have cruised extensively in
Mexico say the amp hour meters are an essential item in the proper maintenance of
the battery bank. It is especially useful if you have "non-linear"
charging devices like solar panels and wind generators adding amp-hours back
into the bank.
A properly used hydrometer tells you a lot
more than a meter, though... I have
found the analog panel meters to be of limited utility since the voltage
reading can be a poor indicator of the state of charge if there has been no
load on the battery for a while. I suspect (but have never calculated) that the
amp-hour meter pays for itself in extended battery life. The Glacier Bay web page (www.glacierbay.com) has a really good article in
their technical library on the design and maintenance of battery banks.
John Lewis March
2003
__________________________________________________________________________________
John,
How
difficult did you find doing all the wiring? I'm assuming that this a shunt
unit that is installed on the ground side of the battery?
I've seen
some new technology hitting the market whereby a shunt is not needed. Some of
the new devices are supposed to read the inductance on the battery cables. This
would make installation a snap. But, I don't think they would be as accurate as
a shunt.
John Hovan March 2003
__________________________________________________________________________________
On the NorSea, the installation was more
difficult because the electrical system had not been designed with the
E-meter in mind. On the new Tayana, it’s a piece of cake. The link 20 uses a
dual shunt where one end of the shunt is tied together and the other is
separate for the two banks. There are separate, twisted-pairs of sense wires
going to each side of the shunt.
The Tayana has a negative electrical buss
in the lazarette where all the major black cables come together. I just made a
4" cable to go from that buss to the shunt and connected the battery bank
cables to the shunt instead of the buss. The positive electrical buss is
in the same little cabinet so those connections are easy too. I still have a
few more wires to connect before I can see if it all works but its not a
difficult install, especially in the spacious Tayana.
I have seen ammeters that use inductance
sensors and suspect they are adequate for that purpose but would wonder how
noise sensitive they would be when the amp data is being integrated over time.
The instructions with the link 20 seem very concerned about shielding the sense
wires from interference and they sell a special cable that consists of a set of
twisted pairs twisted inside a polypro sheath. If you do the install, I think
this special cable is a bargain compared with making up the cable
yourself. If you install the link 10 to
monitor one bank, its easier because you just leave your existing, starting
battery wiring in place and only put the shunt on the house bank.
This is a one-day project if you have all
the crimp fittings and cables on hand.
John
Lewis March
2003
__________________________________________________________________________________
I
recently replaced my 8D Gel batteries. After considerable shopping, a great
deal was found at batterystuff.com. A pleasure to do business with...I highly recommend
them.
www.4unique.com/battery/batteries.htm
Also, spoke with a battery manufacturer who sells both AGM & Gel batteries.
He admitted that AGM are not as durable as Gel's when deep-cycled.
Gil Katz s/v Freedom T-52
March
2003
__________________________________________________________________________________
Sometimes you can restore an apparently
dead gel cell by inverting it and charging it while inverted.
Rich
Hampel March
2003
__________________________________________________________________________________
Prudence, my Tayana 37, has two battery
banks, both 8Ds. One is used for starting and one for the house. I'm engaged in
updating the alternator charging system and am interested in what others have
done.
Do you suggest a "battery
combiner" or some other such device to separate the charging systems?
How about a manual system to isolate
one bank from the other for charging purposes?
Please suggest specifics, in other
words, my local West Marine shop is promoting a Xantrex battery combiner, for
~$200 which would provide automatic protection. The Xantrex unit also
electronically "separates" each bank until they both reach parity,
then combines the two to bring them up to full charge.
Is there any other
device/system/idea(s) I should be considering?
BTW, I currently have a 100-amp
alternator into a Blue Seas DC Parallel Panel. This panel keeps the house and
starting banks separate, and can manually combine the two for emergencies.
John Kalpus S/V Prudence
Tayana 37 San Diego June 2003
__________________________________________________________________________________
Balmar has a new device called a dual
charge that is supposed to allow you to charge a second bank independently
(even if its a different type of battery)....
If you put both your 8Ds in one big
bank, you would be able to cram electrons into it faster. Buy a smaller battery
for engine starting and rig a switch that would let you select the house bank
for engine starting if necessary.
Glacier Bay has a very good article
about battery bank sizing in their technical library: www.glacierbay.com.
John
Lewis June
2003
__________________________________________________________________________________
Subject:
Charging separate battery banks...
The cable connecting the batteries should be
a standard battery cable and NAPA sells them in different lengths. Since the distance between the connectors
(positive on one battery and negative on the other battery) is very short,
heating and voltage drop are not issues for house batteries, since the current
is less than 100-amps and the wire about 1 cm in diameter. Copper can carry
100,000 amps before significant heating and failure occur. Most failures occur at connections where the
cross-sectional area is small.
s/v ATHENA Jim Clemens June
2003
__________________________________________________________________________________
Subject: Golf-cart batteries
The T-125 is rated at 235 Amp Hours and
weighs 66 lbs. The T-105 is rated at 225 Amp Hours and weighs 62 lbs. I have
always used the T-105’s which I buy from a local golf cart dealer for about
$55.00 ea. The T-125s costs about $68.00 each (here in SC).
James W. Smiley Isle of Palms, SC June
2003
__________________________________________________________________________________
Subject:
battery cable
The marine grade cable is tinned, and
generally has a more robust insulation on it. I would not use automotive cable,
as the strand size is a little on the large size, making the cable stiffer
(harder to run and more prone to fatigue).
I have heard of people using welding
cable. It has a very heavy insulation and very small strand size. But it is not
tinned, making it more prone to corrosion.
If it were my project, I would shop around and get the best deal I could
on marine-grade, tinned cable. Do not underestimate the importance of properly
making and sealing the terminal ends. That is probably more important than the
cable you use.
Frank Timmons V42 Magic Dragon
Deltaville, VA August 2003
__________________________________________________________________________________
Subject:
battery cable
Frank,
Thanks for your reply and I will follow
your advice.. The connectors on the cables that I have removed have a very nice
double crimp and are sealed with something. Is there a reasonably priced tool
for the crimping? What should I use to seal the connectors?
Thanks, Alan Jett August 2003
__________________________________________________________________________________
Alan
The price of a double crimper is
outrageous (a good unit is $200-$300). But that is the only proper way to put
the fittings on the large 2/0 cable.
However, most chandleries, including West Marine, have double action
crimpers available at no charge. Some places, such as San Diego Marine
Exchange, even allow you to borrow the crimpers for an hour or two so you can
do the work on the boat itself.
I suggest that you confine your
choice of wires to proper marine tinned wire. Slip on oversized heat shrink
tubing before you put on the crimp connector; double crimp the correct size
connector based on screw diameter; then cover the opening of the base of the
connector with liquid black tape; then slide the heat shrink and heat it to
seal the whole thing. The liquid black tape should ooze out.
regards, Harvey August
2003
__________________________________________________________________________________
Harvey:
Something I have done to keep costs
down, is to use double "O" non-tin wire, saving some money, but I
coat the ends and battery cable terminals with Corrosion Block. Since 1995,
when I got my boat, I haven't had a bit of corrosion. The stuff really does
well as a Di-Electric fluid to displace water, salt laden moisture and won't
conduct electricity. Most folks are turned off by the 18 dollar price per can
but I also use it on my rigging to displace moisture, my computer and track
ball (which did wonders to make it work smoothly) and sprayed it on my computer
parts, e.g. connections. I also ran a long, 33 feet of non-tin double wire to
my windlass for both negative and positive wires, and have used it in Mexico
extensively and coated the ends with C-Block also. Except for moderate
stiffness of the wire, similar to tinned stuff, no rusts or corrosion at
all. In environments with lead acid
batteries, a routine coating, maybe done annually, could prove helpful. AGM
batteries, I feel, are not prone to having the terminals or wires become
affected by corrosion, but coating them won't hurt either. I also coat engine
room parts with it, but keep it away from rubber hoses, except for clamps.
Outboard motors, pumps and similar electrical equipment will last a whole lot
more.
Another trick I use for terminals is
either Red or White acrylic nail polish, for purchase at most Walgreens for a
buck. I coat them accordingly, and that helps, and please make sure that you
explain the bottles of nail polish to your significant other, so there are no
misunderstandings. Take care.
Nicholas "Eclipse" 42cc San
Diego, CA August
2003
__________________________________________________________________________________
Has anyone had experience with the
Lewco chargers for batteries? My 6-volt golf cart batteries (Trojan 105 units) are
only 3 years old, have on two occasions been over discharged when the shore
power was off for several days and the refrigerator running. But I had
generally taken care of the batteries properly. But they now seem to fail to
hold a charge and have to be replaced. I did notice that I had made a note at
the time I installed them that their specific gravity was somewhat low for new
batteries. But I wonder if the Lewco has performed properly.
regards, Harvey October 2003
__________________________________________________________________________________
Sidenote:
Go to www.amplepower.com website and
do a site search for "battery conditioning" or "battery
reconditioning" Sometimes a battery can be 'reconditioned' via a specific
manual discharge/recharge protocol .... back to useful life.
BTW: New batteries have to be properly
'cycled/conditioned' before putting on service ..... or relatively short life;
same process to 'recondition'. ;-)
Rich
Hampel October 2003
__________________________________________________________________________________
In a note Harvey Karten wrote: " But they now seem to fail to hold a
charge."
Hi Harvey, could you please quantify
what you mean by your statement. Golf
cart batteries can be completely discharged and then recharged without
significant damage? So if you quantify your statement, then maybe a better
description of the problem would be available. Also, have you contacted the
manufacturer's technical support team? They are usually very helpful.
Finally, slight variations in the PH
of the electrolyte are not a major issue and, in fact, there are references to
changing the PH of a battery as a function of the ambient temperature of the
batteries. Try Nigel Calder’s book on this subject. I run my batteries with a
PH for tropical settings - lower PH setting and my generator battery has lasted
for five years. Most batteries have their life shortened by being overcharged.
Typical case is letting batteries sit on a battery charger constantly. Genset
batteries are usually isolated from the other batteries. This is done so that
if one inadvertently discharges the house batteries and the main engine
battery, they can then be recharged from the generator using on-board battery
chargers.
This is a configuration used on most
long distance cruising boats, since one does not want to get caught in
"nowhere" with a complete set of dead batteries.
Jim Clemens October 2003
__________________________________________________________________________________
Jim,
My statement "But they now seem
to fail to hold a charge" was an implication based on the fact that when
preparing to pull away from the dock, I disconnected the shore power. I then
tried to start the engine, and rather than the very brisk immediate start, the
starter barely turned over when cranking from my house bank (a pair of 6-volt
Golf Cart batteries). I then shifted to my "starter battery", a
12-volt dual function starter/deep cycle, and the engine started immediately.
The same thing happened again today.
I turned off the engine and checked the voltage on the house bank with the
digital voltmeter built in to the Link 10, and was surprised to see that the
voltage was still reading about 12.8 volts.
At the moment, I am entertaining
several different thoughts as to what might be happening, but would welcome
some more knowledgeable advice.
1)
Perhaps there is a partial break in the cable from the house bank resulting in
a lack of sufficient current to the starter. After checking the voltage on the
batteries after trying to start, I didn't see a major voltage drop as expected
if the batteries are dying.
2)
Perhaps the starter is defective - but then why did the smaller 12-volt battery
- and with a somewhat lower residual charge of only about 12. 6 volts - manage
to start the engine so easily.
3)
Perhaps the golf cart batteries are close to the end of their effective life in
terms of reserve capacity. However, when
I checked the specific gravity of each of the cells in the golf cart batteries,
they were all almost perfectly equal and gave readings of about 1.27.
Interestingly, the 12-volt battery
that so easily started the motor was extremely low on electrolyte. I therefore
could not get an accurate reading of the specific gravity, as I had to add a
great deal of water. Once it comes to equilibrium by tomorrow morning, I will
be able to check that out.
The point raised by Ted Tomasek is of
interest - that the Lewco is a single stage design charger, rather than the
more desirable three-stage charger. This could well result in overcharging,
with progressive decline in battery reserve.
I am prepared to replace all the
batteries, but rather than risk repeating this short life of the batteries,
would like to know if the Lewco design is really so poor that it would worth
the price of replacing it with a verified three stage charger?
The suggestion that I deep discharge
the batteries repeatedly is made by Ample Power Technologies. They claim that a
golf cart battery should be deep discharged about three times to restore its
ability to take a full charge. Sounds a
bit like using leeches to get rid of the "bad blood", but that might
serve as a desulfating regimen.
regards, Harvey October
2003
__________________________________________________________________________________
Harvey,
Everything I read indicates a
three-stage charger (and a three-stage alternator controller) do what is best
for your battery life. Of course, you'll have to calculate the cost/benefit
ratio of buying a new charger compared with living with a shortened battery
life.
Here are some very lucid articles on battery death, the rationale behind
three-stage charging, etc:
http://www.e-marine-inc.com/articles/battery_charging.html
http://www.jackrabbitmarine.com/reference/dialogs_list.html
HTH, Charlie s/v Kamaloha T37
#542 October 2003
__________________________________________________________________________________
Hi Harvey,
Nice description of the problem. I would
probably start to resolve this problem in the following way.
First check all exposed electrical
connections for any corrosion. Then check the wiring. It should all be
multi-strand and securely wire tied in place. The starter motor can draw up to
100+ amps and even very small resistance’s (R < 0.1 ohm) at terminal lugs,
in the wire and switch contact points can cause enough resistance to limit the
starting current. Then there is the solenoid that actually is operated by the
starter switch. If it is the same one for both battery banks, then it can be
eliminated as a cause, since it works with the starter battery. Since you have
checked the voltage of the "coupled" golf cart batteries and it is
acceptable, then there is the possibility that internal resistance is building
up in the house bank batteries. Sulfating is one method of increasing the
internal resistance and lowering the current output of batteries. So
"deep" cycling them is one method of reducing the sulfation product on
the battery plates. The high voltage applied while charging them helps to break
up the sulfate deposit on the electrode.
There is something else to keep in
mind. Starter batteries and deep cycle batteries are very different types of
batteries. The difference is in the internal plate design. Starter batteries
are designed to yield huge current outputs for short periods of time, while
deep cycle batteries are made to yield moderate currents ( > 100 amperes -
exact amount depends on the battery size, specs., etc.). You stated that the
starter motor battery was a deep cycle/starting battery. I would suggest that
you check this out with the manufacturer. Many boats are wired so that the main
engine starter battery can be paralleled with the house bank batteries. But I
have found this to be a risky situation. One can inadvertently draw down the
starter battery, as one draws down the house bank batteries. What I usually do
is disconnect the starter battery from house bank when I am at a marina or on
anchor. I also always keep the genset battery isolated from the other batteries
(belt and suspenders approach).
Now the comments regarding the
battery charger are very important. I use Statpower three-stage smart battery
chargers - model 40+, and they work very well. But even these have a tendency
to overcharge batteries if they are left on all the time when the boat is at
the marina - shore power. The batteries will be over charged and the indication
of this condition happening is that the battery temperature starts to increase
due to an internal resistance build-up. One finally reaches a internal battery
temperature where the batteries give off an acid smell. This happened to my
house and starter batteries, and they all failed in a time span close to each
other - 3 years. This internal
resistance will also limit the current output of the batteries and may be the
first indication of battery overcharging. The test voltage was acceptable.
My genset battery is not sitting with the
charger attached and it is still working beautifully after five years and years
of daily use. The genset has an internal alternator that recharges the battery.
So the evidence is consistent with what many professional boaters, charter
captains and others have told me. Basically, overcharging is the most common
failure mode for marine batteries.
Finally, I would recommend a smart
three-stage battery charger and one that also has the capability to act as a
constant voltage source. The Statpower chargers can be set to supply a constant
voltage and varying current. There are two models - one that supplies up to 20
amperes and another that supplies up to 40 amperes.
I have to check this out. It's on my
list of many things to do. If it is so, then at the marina after recharging the
batteries to full charge, one could disconnect the batteries from the charger,
and then run the boat systems off the charger and let the batteries
"rest". I am still in the learning mode on this secondary issue.
However, if it is possible, then one can extend the life of batteries and
eliminate a potential source of fire. Just a little rewiring is necessary.
I agree with the comments made by Ted
Tomasek. It is important to use a three-stage battery charger.
Jim Clemens s/v ATHENA T58 October 2003
__________________________________________________________________________________
Many thanks to the several useful
letters from the members of the group. This is probably far too lengthy a
report, but this was a day that I am unlikely to ever forget! Having taken Ted, Jim's and several other
people's advice to get rid of the Lewco charger and get a modern type of
three-stage charger, I stopped at the local Chandlery to ask the price and
their suggestions as to various brands. They were also insistent that the Lewco
chargers are the major source of battery failure - usually due to overheating
and evaporation of the water from the sulfuric acid. He suggested the new
generation of Newmar three-stage chargers, such as the PT-25. After hearing the
price (ca. $400), I gulped and thought that will have to be the next purchase -
maybe even sometime in the next few days. A prescient thought, perhaps, but a
foolish hope that I could stall spending a hunk of dough for a bit longer.
One of the points I had made was that
I found that the starter battery fluid level was way down and the plates
clearly exposed. I topped the battery cells with distilled water yesterday, and
left the battery on charge with my Lewco.
I went to the boat and by chance,
replaced the battery cover, and the plywood sheets between the batteries and
the overlying quarter berth. I tried to start the motor using only the house
bank, while watching the readings on the digital voltmeter on the Link 10 that
monitors the house bank. I was a bit surprised to find that even though the
starter quickly ran down and then failed to turn over completely, the voltage
on the house bank didn't drop significantly, and remained in the range of 12.7
volts. I then shifted to the starter battery plus the house bank and it started
right up. As a chronic tinkerer, I
couldn't leave well enough alone, and decided to pull the kill cable while
turning over the starter, as a test of the battery reserve, as suggested by Calder
and a number of other mayvins. I turned the key, heard an abortive start and
then a "pop". After that, all was dead as a doornail. I couldn't turn
over the engine, and couldn't even get a clicking from the solenoid. I feared
that I really had a dead starter. But I then found that I had no power to my
bilge pump or several other electronics.
At that point, and for reasons that
weren't completely based on clear thinking, I decided to check the batteries. I
removed the mattress on the quarter berth and then the plywood. I was very
puzzled as I couldn't see the plastic piece that covers three of the six wet
cells on the 12-volt starter battery. But I did notice that there was a black
gooey stain on the plywood that had been over the battery. There were scattered
bits of fluid, and I suspected that they might be sulfuric acid. Closer
examination of the battery revealed that the casing of the battery had exploded
and the top half of the battery was lifted up! The battery post was completely
melted down and the battery wire (1/0 wire) lying freely in the compartment!
The blessing was that I had the battery in a battery box with a sealed bottom,
rather than just in an open battery tray.
After some really cautious moves, I
managed to get the battery out of the battery box and into a spare battery box
that could be safely moved about. I was very concerned about the dangers of
working with a ruptured battery still filled with sulfuric acid. The odor of
the sulfuric acid was very distinctive.
Back to San Diego Marine Exchange - I
bought the Newmar PT 25 charger and a new "starter/deep cycle 27M
battery". The person at SD Marine Exchange suggested that what had
apparently happened was that the original battery had gone so dry, that when I
added water to the cells, it further led to a direct short circuit across the
fused plates. When I drew current for the starter it completely shorted and
caused the battery to explode. He suggested that the starter might also be
partly responsible, and the wiring from the battery to the starter was exposed to
very high currents, and to carefully check all the wiring.
I found the wiring to the starter was
OK, with no indication of blistering or burns or weakness. I installed the new
battery, wired in the old house bank, disconnected the old Lewco charger completely,
and tried starting the boat. Success on the first try, with very fast starting
of the engine! I tested both the new starter battery as well as the house bank
alone, and found that the engine started within a second or less, with the
starter giving a nice healthy sound.
My hope is that the starter is OK.
The really frightening part was the
realization that an exploding battery could well have spewed hot sulfuric acid
all over the place. It was only a chance event that prompted me to put the
battery cover back on and then put the plywood back in place over the battery
compartment. Otherwise, the outcome might have been much more damaging.
I plan to go back to the boat in the
morning to wire in the new 3-stage Newmar charger. By that time, I thought I
was lucky to get away with only a hit to my credit card, and not some major
burns to me by the sulfuric acid. I begin to wonder if those sealed AGM
batteries might not be the safest way to go?
regards, Harvey October 2003
__________________________________________________________________________________
Hi Harvey,
Glad you are ok and things got worked out.
Remember my remark about the battery heating.
When a battery does start heating internally, the internal temperature
is very high, and the acid can boil and cause an explosion.
That is why the U.S. Coast Guard
rules mandate that batteries be in battery boxes with tops.
Another final point to all, when working
with 12 volt batteries or circuits, please be very careful.
Always wear safety glasses. There was once
a discussion of whether one could be electrocuted with 12 volts, but that is
not the dangerous aspect.
IF ONE INADVERENTLY SHORTS POSITVE
TO NEGATIVE, THERE IS ENOUGH ENERGY IN THE BATTERIES TO MELT AND SPLATTER THE
METALLIC OBJECT, SUCH AS A WIRE OR A SCREWDRIVER.
SECOND, BATTERY ACID (SULFURIC ACID) IS
NASTY STUFF. IT BURNS BY REMOVING WATER
FROM THE SKIN AND CREATES HEAT IN THE PROCESS.
THE BURNS ARE REALLY BAD. ALSO BE
CAREFUL IN ADDING WATER TO ACID, SINCE IT CAN ALSO SPLATTER.
THUS ALWAYS WEAR EYE SHIELDS OR
GLASSES WHEN WORKING WITH LIVE CIRCUITS AND NEAR BATTERIES!
Jim Clemens s/v -ATHENA
T58 October 2003
__________________________________________________________________________________
Subject:
Battery Life and Loads on Starter Battery - where to wire in the Bilge pump?
A related issue to the topic of starter
batteries vs. house banks now confronts me. When I bought the boat, the small
electric bilge pump was wired in on the same circuit as the starter battery (?I
think that was how it was?). There was a direct input from the battery to the
circuit breaker for this main bilge pump (a Rule 1100 with integrated float
switch).
In the course of time, I added a set
of golf carts as the house bank, but left the bilge pump on the starter
circuit. I'm not even sure that I had a rationale for doing this. In order to
provide sufficient power to run the bilge pump long enough to possibly note
that the boat was slowly filling with water, I used a "Dual Purpose"
Starter/Deep Cycle 27 battery.
However, I now wonder what would be
the best course of action. Should the primary bilge pump be directly wired
(through the obvious circuit breaker) to the house bank or the starter battery?
Since the house bank also runs the refrigerator, my thought was that the house
bank would be more likely to be seriously depleted just when I might need it
the most. The starter battery generally gets so little use that it might have
the longer lasting charge still available to run the bilge pump in an
unattended emergency situation.
I also have a large 3700 Rule pump
which is mounted higher in the bilge and runs from the main house bank.
Any input from the members would be
welcome.
P.S. Ever since installing GFO Teflon stuffing, the bilge pump hardly ever goes
on, as indicated by our bilge pump counter. But ...
Harvey J. Karten, M.D. October 2003
__________________________________________________________________________________
Interesting conundrum. Want the maximum
possible utility of the emergency bilge pump? It probably burns about 6 - 8
amps, right? (check this, I'm not sure what the Rule 1100 takes, but that ought
to be about right...) In that case, go to Radio Shaft and get a 15A full-wave
(bridge) rectifier, attach the house battery to one "AC" terminal,
the starter battery to the other "AC" terminal, and the bilge pump
circuit breaker to the "+" terminal. You lose 0.6v of voltage to run
the pump, but whichever battery has the greater voltage will run the pump, and
in a sinking situation, both batteries will have to go dead before it gives up.
(By the way, a 14v "trickle charger" could then be connected to the
"-" terminal to provide a float charge (13.4v) to both batteries.)
The bridge rectifier isolates one battery from the other.
Be sure to bolt the heatsink of the
rectifier to some big piece of metal to keep it cool.
Charlie s/v Kamaloha T37 #542 October 2003
__________________________________________________________________________________
Downwind Marine in San Diego has black
plastic battery filling jugs with auto-shutoff nozzles.
Downwind Marine
2804
Canon Street
San
Diego, CA 92106
(619)
224-2733
John Kalpus Prudence Tayana 37 San Diego October 2003
__________________________________________________________________________________
I check my batteries about every two months
and take note of any cells that are using too much water. It can be the first
warning of a bad cell within the battery.
As for nominal filling, I use a
technique like the basting bulb. I bought a funnel with a long neck and narrow
1/8" opening in a hardware store. This fits nicely into the cell tops ad
also guards against acid splashes. I keep about three gallons of distilled
water on the boat at all times, so when it is time to add a little water to the
batteries, I fill a small plastic bottle and pour it through the funnel. Thus I
eliminate both the splash hazard and the overfilling hazard. A really cheap design and you can find these
parts in any hardware or dollar discount store.
Jim Clemens s/v ATHENA T58 October 2003
__________________________________________________________________________________
Catalytic
Battery Caps for flooded cell batteries:
Catalytic battery caps capture hydrogen
and oxygen as battery water gases and bubbles.
It then uses a platinum catalyst to recombine the hydrogen atoms with an
oxygen atom. The reconstituted water
then drips back down into the battery. Battery water usage is decreased better
than 95%. (Wayne Strausbaugh – 2005)
Contact Mr. George Peroni at Hydrocap Corp., 975 N.W. 95 Street, Miami, FL
33150, telephone: (305) 696-2504.
Also, check out these websites:
http://www.ibiblio.org/pub/academic/environment/alternative-energy/energy-resources/homepower-magazine/archives/11/11pg37.txt
(2
lines or more – you may have to cut/paste this into your browser. Very good information…)
http://www.solar-electric.com/hydrocaps.html
Wayne
V-42 C/C
RESTLESS October 2003
__________________________________________________________________________________
Harvey,
I talked to George Peroni at Hydrocap
Corp.(975 N.W. 95 Street, Miami, FL 33150, telephone: (305) 696-2504, today. He
makes the caps. He made a set for the moon buggy that the astronauts used
and says NASA still monitors its signal today after 33 years. The caps were
standard inside but modified on the outside to handle no atmosphere. Those must
be good batteries as well! The solar charger is still working... Pretty
impressive - 33 years on the moon with minimal water loss! George indicated
that the lifespan is indefinite if they are treated normally. Mine work great after
15 years. He will sell them for $7 a
piece for less than 40 (and that includes shipping, insurance, etc.) or $6 a
piece for more than 40 (that's $18 for one 6-volt battery or $36 for 2 -
expensive but they have been worth it to me). If you buy new batteries, he can
adapt the old caps to the new screw-in configuration if it is different. My
Rolls use the standard bayonet type.
Wayne
V-42 C/C
RESTLESS
October 2003
_________________________________________________________________________________
Subject: Safety around batteries
I second that... a friend of mine was
removing a battery cable when his wedding ring completed the circuit between
the wrench and the opposite battery terminal. The ring became instantly
white-hot and did a nice job of removing his finger. As a result I always try
to use insulated wrenches and screw-drivers when applying them to electrical
connections.
Charlie Freeman s/v Kamaloha T37
#542 October 2003
__________________________________________________________________________________
I guess that's one good reason not to wear
rings, (or jewelry of any sort) while performing maintenance, or just plain
sailing for that matter.
While replacing a 4D housebank this fall,
I let a tool slip from my hand and it completed the circuit by touching both
positive and negative. Sparks flew and a melted tool was the result. Gave me a
good scare on just how close you are to getting zapped if you're not extremely
careful around boat batteries.
B Ashby s/v Rhythm Cal 44
#016 (looking at Tayana's) November 2003
__________________________________________________________________________________
Subject:
bilge battery location
Have you ever had your bilge flood and water
up over your cabin sole? The last place
I'd want to put my batteries is where they'd be vulnerable to submersion.
Sandra
Blake T37 Traveler Hull
#328 September 2004
__________________________________________________________________________________
Sandra,
I was amazed when I saw the location
of the batteries on an Island Packet (or at least on the one that I looked at
in detail). Their batteries were below the cabin sole. But they were in
watertight containers, and I wasn't certain how they lead the wires out and
still keep them waterproof. I was impressed with the heavy-duty steel bars they
used to keep them in place in the event of a knockdown/rollover.
None of us want to have water coming
up over the sole. But it happens! I figure that if the bottom of my battery box
is at about the waterline, and if the box is sealed at the bottom, then the
water has to rise about 12 inches above the waterline to short out the
batteries. Not a lot of safety, but better than being below the cabin sole. The
problem of maintaining a waterproof lead of the battery cables as they exit the
box was something I didn't find simple to achieve in my mind.
I would not suggest putting screws
through the bottom of the polyethylene battery basket. If sulfuric acid spills,
as in the exploded battery that John Hovan, I and others, experienced, then
there will be free sulfuric acid sloshing around in the battery box. If there
are screws, they will be chewed up by the acid. If the screw holes are not well
sealed, the acid will immediately start leaking out. Concentrated sulfuric acid
is very nasty stuff.
In view of the weight of a full
complement of batteries, it certainly would be nice to be able to store them
low in the bilge in the midline. But I don't think that is quite feasible. I have seen it mounted on the shelf above the
engine just aft of the companionway steps. I felt that was much too vulnerable,
especially as that shelf is not all that sturdy, and the weight of the
batteries were substantial.
We mounted our hot water heater in
the aft lazarette just in front of the steering assembly. Might be more
sensible to move that to an alternate location and build a large battery box in
that location, as suggested by one of our members. That would keep it low and
in the midline. It would also keep it close to the power panel.
regards, Harvey J. Karten September 2004
__________________________________________________________________________________
Harvey,
Further to your comments on battery
location. I own a Tayana 42 aft cockpit #31. I had major flood this spring. The
high water mark is still 8 inches below the table level in the main salon. The
table post still has the tide line. My batteries are all below the cabin sole.
The aft house is a large gel battery. It
was completely under water and continued to run. It is completely encased in
plastic. The forward windlass gel was not affected. However the starter motor battery ran the
bilge pump when it was under water for the 6 to 8 hours with 4 pumps running
that it took to clear the water. It died
as soon as the boat was empty. Good battery but it had water in it at the end.
I live in Toronto so the water was fresh not salt water. I replaced the starter
battery, the bilge pump, the house pressure pump and worked to save the engine.
The jury is still out on that. The biggest problem was that the discarded oil
that had accumulated deep down in the bilge rose up on top of the water and
then draped itself all over every bit of teak below the tide line. It was
scrubbed off with a product called All Off and a series of toothbrushes. On
balance, I think it was worth it to continue to keep the heavy batteries low in
the boat.
On another topic: Have any Tayana 42
owners ever wondered how heavy their boats are? I wondered until yesterday.
Coco I was hauled out for the winter and the crane operator told me she weighed
34,000 lbs. That is with full oil tanks and no mast.
David Campbell Coco I aft cockpit #31 September 2004
__________________________________________________________________________________
You might consider an additional 'intake' line with a cowl, to help pressurize the battery box ... to create a 'sweep volume of outside air' to aid the diffusion of hydrogen and acid vapors.
Rich Hampel November 2004
__________________________________________________________________________________
Thanks Rich...
Of course that makes sense. I'm curious
what others have done, if anything, to increase the flow of air across the
batteries.
Since the batteries are below my
quarterberth, I don't want a howling gale blowing under the bunk. (-; I gentle
zephyr would be about right, or perhaps I shouldn't worry about it at all.
It seems to me that most battery
installations I've seen, under the floorboards, beneath the quarterberth, in
the engine compartment, nary a thought is given to where those nasty hydrogen
molecules are going. )-;
Am I making a mountain out of a
molehill, er, I mean, a hydrogen bomb out of a firecracker?
Regards, John Kalpus S/V
Prudence San Diego November 2004
(see catalytic battery caps above on pages 13 &
14)
__________________________________________________________________________________
Two tubes in/out of the locker should
be sufficient .... one at the bottom of the locker and one at the top of the
locker, the thermal difference (warm battery when charging; colder locker
surfaces) and the placement of the hi/lo tubes should be enough to create a
natural 'thermo-syphon' + plus any breeze that passes the ends of the tubes.
Rich
Hampel November 2004
__________________________________________________________________________________
Can someone, please, explain to me (I'm
scientifically challenged) why I cannot dry out a piece of wood that has become
saturated with battery acid. The wood turned dark and almost black and I'm
assuming that it is still damp because it has not lightened back up after
putting heat lamps on it for hours and letting it air dry for many moons. Is
there no hope?
Thanks, John Keefe CT37 No.63 ODYSSEA Youngstown, NY
February 2005
__________________________________________________________________________________
Subject:
Wood soaked with battery acid
John,
Sorry, but there is no hope. Battery
acid is an extremely corrosive substance (concentrated sulfuric acid). It
carbonizes wood, and completely destroys any structural strength that the wood
may have provided.
Just replace the wood. You should
also store your batteries in plastic cases, well secured to prevent the battery
from sliding around or falling over, using a nylon strap. Nylon strapping is
relatively impervious to sulfuric acid. But it's a good idea to replace the
straps if they contact the acid.
Sulfuric acid is very nasty stuff. If you
splash even a small amount into your eye, you should immediately flush it with
copious quantities of water.
regards, Harvey February 2005
__________________________________________________________________________________
Harvey,
Thanks for the answer although that
is not what I wanted to hear. Well, it looks like another project is in order.
The previous owner spilled acid, somehow, in the battery compartment located
under the aft starboard berth. I've
tried to dry it over the winter months but it looks like I'll have to take off
the blue blazer and Sperry's and get down to rebuilding the wood floor and
associated wood supports in that area. I can't believe that Tayana didn't
install a proper battery box. I thought about maybe relocating them to
somewhere else but I can't really think of a better place. I guess they offset
some of the heavier port side things, anyway.
How bloody awful!
Regards, John Keefe CT37 No.63
ODYSSEA Youngstown, NY February 2005
__________________________________________________________________________________
Hi
John,
Sorry to be the bearer of bad news. This
can happen if a battery explodes, as happened to me about a year ago. I think
the same thing happened to one of our other members. Fortunately, I had the battery in a plastic
battery box, and my head was nowhere near it when it blew (due to a short and
my own stupidity. I left a connector loose when checking something a few
minutes prior. Batteries don't just
"blow up" spontaneously, as a rule.) But I have even had a situation
when a brand new battery had a crack in the casing and started leaking within a
few hours of installation.
The skimpy battery boxes usually sold
at West Marine are not what you want. Get a hefty plastic box (with walls and
floor about 1/4". But do not drill holes in the bottom of the box to
secure it. If acid leaks out, then you again have a problem. The hefty walled
battery box that I have holds two 6V golf cart batteries. It cost about $50 or
$60.
Another strategy, which I may use to
install a second bank of golf cart batteries, is to build a custom battery box
with plywood, fiberglass liner and epoxy. This is shown in Nigel Calder's book,
or in Casey's book. This allows you to fit batteries in odd spaces.
Make sure that you have rods on top
of the batteries box to secure the batteries in the event of a rough sea (or a
drastic capsize and rollover). Check some of the offshore battery storage
solutions in boats like the Island Packet, the Caliber and the Morris. They use
heavy steel rods that are locked in place on top of the battery box, to prevent
battery movement in the event of a rollover.
That's on my list of things to do if
I take off for blue water, but at the moment, I just secure the batteries with
nylon straps and wooden 2x4's on the top.
regards, Harvey February 2005
__________________________________________________________________________________
Hi
Harvey, Bill,
Thanks for the info and tips. On my last
boat, I made battery boxes just as you described, Harvey, from information in
Carlie Wing's book called "Boatowner's Illustrated Handbook of
Wiring" wherein he gave detailed instructions on making heavy duty boxes
out of 3/4" exterior plywood and fiberglass, etc. They worked out great.
I'm going to do the same thing now
for Odyssea. I'll build a custom box to hold four golf cart batteries and have
two separate banks to start with which will be enough for the sailing I will be
doing. I now have the opportunity to glass onto the hull heavy wood supports to
support the heavy-duty battery box and the new "floor" that I will
need to install in the aft cabin. When I get to it I'll take photos and pass
them along.
Bill, AGM batteries are for all you
guys with lots of disposable income....I'm cheap plus I get golf cart batteries
from one of our vendors at work at a very nice price.
Regards, John Keefe CT37 No.63 ODYSSEA Youngstown,
NY February 2005
__________________________________________________________________________________
Yep, AGM’s are nice, but very pricey. They
also require a change in your voltage regulator. I also recall that you can't
readily mix a bank of AGM's with a regular type of lead-acid, due to slightly
different voltages, and different recharging requirements. For $200 you can get
four golf cart batteries with a capacity of about 210 amp hours. A separate
starter battery of 12 volts is dedicated to the engine. I don't know what a
similar setup would be for AGM’s.
regards, Harvey February 2005
__________________________________________________________________________________
The info I have on AGM’s is that they do
just fine on the same charging programs as flooded batteries. Gel cells are
really sensitive to voltages that are high enough to fully charge a flooded
cell. The AGM’s can’t be run at the extremely high voltages for long periods
that is used to equalize flooded cells.
I think I paid about $1600 for 5 4D AGM’s
and one Type 27 AGM for starting the engine. That would work out to a little
more than $300 for a couple of hundred amp hours. The advantages are that they
can be installed in tighter spaces (no boxes needed), can be installed sideways
if necessary with-out a loss of capacity, are supposed to tolerate total
discharge and still recover, and totally contain the acid so the batteries
would have to be physically damaged for leaks to occur. Mine are two years old
now and show no sign of loosing capacity. They live an easy life and have
rarely been discharged below 60%. I can sit on the hook for 5 or 6 days, run
the fridge, coffee maker TV, computer and forget to turn off the anchor light
and still don’t run the bank below 60 %.
Glacier bay is a great source of technical
info on battery banks. Since they are not trying to sell me any particular kind
of battery, I tend to trust them.
John
Lewis February 2005
__________________________________________________________________________________
AGM's are more expensive but I really
believe that they are worth the extra money. I used to sell Optima's years ago
as part of UPS systems where the abuse was excessive. After trying virtually
all the batteries on the market we found that the Optima consistently outlived
all the others. We still do mil-spec UPS's and recommend Optimas, but we don't
sell them because of the company. They really stand up to the heat and can be
ignored once installed properly.
The reason I recommend Optima's over
other AGM's is because they use a spiral cell, the plate is wrapped up (like a
toilet roll) and jammed tight into the case which makes it very vibration resistant.
They also recover from a flatline state very efficiently. I installed a set of
10 batteries in a mobile aircraft control tower for the air force, they forgot
to switch them off over a long weekend and after the main power was turned off
they ran the unit until they were flattened. The Corporal put a chart on them
to check the recovery and was astounded at how good they were.
I run them in our boats and cars just
using the regular regulator and mix them with a bunch of deep cycle UPS
batteries that I got for free, but that's not really recommended.
Please note that I have absolutely no
financial interest in the optima company and buy my Optima's wherever I can
find them on sale :-)
Bill & Sue T37 Wellantanzerin Port Hope, Canada March 2005
__________________________________________________________________________________
Hey Group...
I've been researching
the install on a new electric windlass for my T37, Prudence. I was planning on
running 70 feet of 2/0 wire from my main batteries, under the quarterberth.
THEN it HIT me that I could also simply put another battery under the vee
berth, and dedicate it to the windlass. That would sure simplify the install.
Since it would be rare to be operating the windlass without the engine running,
wouldn't it be a much easier and better installation this way?
What am I NOT thinking
of?
The windlass would be
really running off the dedicated battery, even if the engine were running.
Would this put too much of a load on the charging wires from my alternator to
the vee berth battery while operating the windlass over an extended period of
time? Thanks for the sage advice in advance.
John Kalpus Prudence San Diego May 2005
__________________________________________________________________________________
John,
Won't you still have to run heavy
gauge wire from your alternator to the battery under the V-birth? If you have
Nigel Calder's "BOAT OWNERS MECHANICAL AND ELECTRICAL MANUAL", see
his write-up on windlass wiring on page 534.
Jim (SMILES) May 2005
__________________________________________________________________________________
Hi
John,
Jim is correct. You have to run cables from
the alternator that are rated for the full amount of current drawn from the
alternator to the windlass, assuming that you have an alternator that can keep
up with the current draw. With a LoFrans 1200, you draw a full 100 amps at
12-volts, slightly less at the nearly 14-volts that the alternator is
generating when the engine is running. You also have to use the rating tables
for a 3% voltage drop or you risk burning out your motor in the windlass. You
end up requiring the same 2/0 wiring as if your battery were closer to the
engine rather than the windlass, according to Calder.
In actual terms, most of the time
that you run your windlass, it is not drawing maximal current, but for those
few occasions when you do, you could easily overload the wiring. If you have to do a number of anchor drops to
find a good anchor set, you will be drawing down your battery.
Another alternative would be to move
your engine and alternator into the bow - sort of like front wheel drive
automobile. That will allow you to also have your batteries up front.
Harvey Karten May 2005
__________________________________________________________________________________