COACH BATTERIES

[Jack & Donna Smith]

I need some info for the Batteries in our 1973 Gas Coach.. When we
bought it, there were 2 WalMart Maxx 29 Deep Cycle Marine Batteries,
875 cranking amps & 675 cold cranking amps. One was installed in the
front battery compartment by the drivers seat & one in the Gennie
Compartment. I installed another of the same "Up Front", and another
under the entry steps, in the places provided. These are all 12V units.
Now they are about ready to be replaced.
Question is: Replaced with what?
My Coach is stored in a Storage area without connections of any kind,
and all the batteries have the knife type disconnect switches.
Would several 6V type be better for my use? AND WHY???
Also, is a smaller size battery, (of same cranking amps) any different
from a physically much larger unit.. Will the larger one have
more "Innerds" and last longer between charges, or have a longer
battery life.??
Most of the camping will be with hookups, but occasionally we will
DryCamp for a couple of days.
Jack Smith
1973FC31
SoCal

[wilfreddrabble]

Jack, The reason for using a pair of 6 volt golf cart batteries as
house batteries to replace a 12 volt battery is that the golf cart
batteries are supposed to be more robust and also able to take more
charge/discharge cycles.

Most of the time, the pair of 6 volt batteries wired together in
series have a higher amp hour rating than the battery they replaced
as well, a nice bonus.

So far as I know (not that I have any personal experience here), most
RV'ers who have tried this setup have been more satisfied with it
than with their previous 12v house battery.

The only downside I know of, aside from extra cost and trying to find
the extra room for those big batteries is maintenance: you have to
top up the golf cart batteries with distilled water regularly. As far
as I know, they aren't "sealed".

John Alldredge


--- In WanderlodgeForum@yahoogroups.com, "Jack & Donna Smith"
wrote:
>
> I need some info for the Batteries in our 1973 Gas Coach.. When we
> bought it, there were 2 WalMart Maxx 29 Deep Cycle Marine
Batteries,
> 875 cranking amps & 675 cold cranking amps. One was installed in
the
> front battery compartment by the drivers seat & one in the Gennie
> Compartment. I installed another of the same "Up Front", and
another
> under the entry steps, in the places provided. These are all 12V
units.
> Now they are about ready to be replaced.
> Question is: Replaced with what?
> My Coach is stored in a Storage area without connections of any
kind,
> and all the batteries have the knife type disconnect switches.
> Would several 6V type be better for my use? AND WHY???
> Also, is a smaller size battery, (of same cranking amps) any
different
> from a physically much larger unit.. Will the larger one have
> more "Innerds" and last longer between charges, or have a longer
> battery life.??
> Most of the camping will be with hookups, but occasionally we will
> DryCamp for a couple of days.
> Jack Smith
> 1973FC31
> SoCal
>

[Don Bradner]

It takes more battery to get more total AH. In my case, the original batteries
were Group 24s, and there was no room to go sideways but plenty of overhead.
6-volt GC batteries are taller, so more battery in the same physical length and
width. Typical Group 24 will be 160-170AH for two, and GC batteries 210-220AH
for two (using two because 6-volt must always be in pairs).

CCA is not particularly related to life or total Amp-hours - depends on how they
engineer the battery. 6-volt GC batteries do not have particularly high CCA
values, but with enough of them that does not matter - 6 of them turn an 8V92
over nicely.

Sealed is a factor of battery type, and 6-volts are made in most (all?) types.
If the type is sealed, the GC battery will be sealed. I have Lifeline AGM
batteries, just as sealed as any other AGM. Never did like checking/topping with
water.

Don Bradner
90 PT40 "Blue Thunder"
Eureka, CA, headed East in a week if the doc gives the OK (fingers crossed!)

On 8/8/2008 at 9:24 PM wilfreddrabble wrote:

>Jack, The reason for using a pair of 6 volt golf cart batteries as
>house batteries to replace a 12 volt battery is that the golf cart
>batteries are supposed to be more robust and also able to take more
>charge/discharge cycles.
>
>Most of the time, the pair of 6 volt batteries wired together in
>series have a higher amp hour rating than the battery they replaced
>as well, a nice bonus.
>
>So far as I know (not that I have any personal experience here), most
>RV'ers who have tried this setup have been more satisfied with it
>than with their previous 12v house battery.
>
>The only downside I know of, aside from extra cost and trying to find
>the extra room for those big batteries is maintenance: you have to
>top up the golf cart batteries with distilled water regularly. As far
>as I know, they aren't "sealed".
>
>John Alldredge
>
>
>--- In WanderlodgeForum@yahoogroups.com, "Jack & Donna Smith"
> wrote:
>>
>> I need some info for the Batteries in our 1973 Gas Coach.. When we
>> bought it, there were 2 WalMart Maxx 29 Deep Cycle Marine
>Batteries,
>> 875 cranking amps & 675 cold cranking amps. One was installed in
>the
>> front battery compartment by the drivers seat & one in the Gennie
>> Compartment. I installed another of the same "Up Front", and
>another
>> under the entry steps, in the places provided. These are all 12V
>units.
>> Now they are about ready to be replaced.
>> Question is: Replaced with what?
>> My Coach is stored in a Storage area without connections of any
>kind,
>> and all the batteries have the knife type disconnect switches.
>> Would several 6V type be better for my use? AND WHY???
>> Also, is a smaller size battery, (of same cranking amps) any
>different
>> from a physically much larger unit.. Will the larger one have
>> more "Innerds" and last longer between charges, or have a longer
>> battery life.??
>> Most of the camping will be with hookups, but occasionally we will
>> DryCamp for a couple of days.
>> Jack Smith
>> 1973FC31
>> SoCal
>>
>
>
>
>------------------------------------
>
>Yahoo! Groups Links
>
>
>

[Henry Jay Hannigan]

--- In WanderlodgeForum@yahoogroups.com, "Jack & Donna Smith"
wrote:
>
> I need some info for the Batteries in our 1973 Gas Coach.. When we
> bought it, there were 2 WalMart Maxx 29 Deep Cycle Marine
Batteries,
> 875 cranking amps & 675 cold cranking amps. One was installed in
the
> front battery compartment by the drivers seat & one in the Gennie
> Compartment. I installed another of the same "Up Front", and
another
> under the entry steps, in the places provided. These are all 12V
units.
> Now they are about ready to be replaced.
> Question is: Replaced with what?
> My Coach is stored in a Storage area without connections of any
kind,
> and all the batteries have the knife type disconnect switches.
> Would several 6V type be better for my use? AND WHY???
> Also, is a smaller size battery, (of same cranking amps) any
different
> from a physically much larger unit.. Will the larger one have
> more "Innerds" and last longer between charges, or have a longer
> battery life.??
> Most of the camping will be with hookups, but occasionally we will
> DryCamp for a couple of days.
> Jack Smith
> 1973FC31
> SoCal
>

[hippieforever3]

OK, first my bonafides.

I have an electrical engineering degree and worked in quality and
reliability in electronics over 30 years. While I'm not the world's
foremost expert in wet storage batteries. I have had some experience
with the quality and reliability of "backup" electrical sources.

ALL known types of rechargeable electrical storage devices (batteries
included) have "memory". The ability for the battery to absorb, store
and discharge energy is related to how much energy was stored and
discharged in recent cycles. It's very much like flexibility in
humans, if you don't slightly over stress your joints occasionally
over time you lose flexibility. You can reduce failure and extend
useful life by totally (over) depleting the battery bank once a month
or more. A perfect way to do this in an RV type application is to run
the air-conditioner until the batteries were clearly struggling then
turm on incandescent lights and leave them on for 6-12 hour AFTER you
can't see the filament glowing. Switch off all loads and use a good
REGULATED low charge rate charger, not the alternator and regulator.
Actually a trickle charger would be perfect.

Now this is not a very practical routine but the closer you could
come to the deep, deep discharge and slow full, full charge the
longer your batteries would last.

In the most basic lead storage battery, the more lead the more
overall storage capacity so in a crude sense the heavier the battery
the more ampere-hours, unless the weight is in the case not the lead.
While shear lead volume determines capacity from the standpoint of
physics, performance is determined by configuration. The thinner the
lead plates are the faster they will charge or discharge (cranking
power). The thinner the plates are the more the battery might be
prone to failure from environmental factors like temperature and
vibration. Here is the dilemma preventing you from picking the best
battery using a scale.

One really good indicator of battery quality is the case and
terminals. Is the case a heavy thick walled rubber compound or is it
a nice thin walled high performance polymer? At the factory the cost
differential is at most $2. What they are charging retail is some
indicator of value. If you can see the plate structure, what does the
workmanship look like? Check the materials of the terminals and the
seals. On almost all batteries the top is a separate piece. Check the
joint construction and workmanship. ANY inconsistency or voids is a
sign of lower quality craftsmanship. Check a couple of different
sizes and cases from the same manufacturer.

There is absolutely no inherent reason why 6 volt golf cart batteries
should be more capable of better handling numerous charge and
discharge cycles than 12 volt batteries although the design of any
battery will impact that and it may be a valid argument that
batteries specifically designed for full charge / discharge
applications will last longer. There are however 12 volt batteries
designed for these same cycles and the extra connections in a 6 volt
system negatively impact reliability and efficiency.

As a general rule you should get better performance and life from
sealed batteries. Typically they will be newer designs, often made on
more modern production lines and there is far less chance that the
electrolyte will become (even slightly) contaminated or non-optimal.

Price vs. performance vs. reliability.
Two $75 55ah 12 volt batteries will be more reliable than one $150
100ah battery but take up twice the space. You can limp in on one of
the $75 cheapies and with proper care ONE of them will last longer
than the $150 battery. Will four $37.50 six volt batteries outperform
either of the other options ... Nope, if one of those four fail,
you're walking.

If you're looking at spending $500 or more on batteries, in a none
emergency replacement, it might be worthwhile to contact the
manufacturer and get the detail specs and reliability data on the
models you are considering.

Happy to help if you have questions.

Regards,
GPSGary

[Henry Jay Hannigan]

Jack:
I am a fan of TROJAN T105 six volt batteries......Two in series is
all u need for house power.......I had mine over seven years and
still fine in motorhome in Australia using a solar setup.
Understand SAMs club has some a little cheaper and a few less
amps....for myself, I like the BEST and for ME, TROJAN T105's are the
best for house batteries.
They list at $169 in Vegas but I got them last month here for $130.
I hear SAMS club batteries are cheaper....Take your pick.
LOL
Regards,
Hank still in Vegas
90SP36








--- In WanderlodgeForum@yahoogroups.com, "Jack & Donna Smith"
wrote:
>
> I need some info for the Batteries in our 1973 Gas Coach.. When we
> bought it, there were 2 WalMart Maxx 29 Deep Cycle Marine
Batteries,
> 875 cranking amps & 675 cold cranking amps. One was installed in
the
> front battery compartment by the drivers seat & one in the Gennie
> Compartment. I installed another of the same "Up Front", and
another
> under the entry steps, in the places provided. These are all 12V
units.
> Now they are about ready to be replaced.
> Question is: Replaced with what?
> My Coach is stored in a Storage area without connections of any
kind,
> and all the batteries have the knife type disconnect switches.
> Would several 6V type be better for my use? AND WHY???
> Also, is a smaller size battery, (of same cranking amps) any
different
> from a physically much larger unit.. Will the larger one have
> more "Innerds" and last longer between charges, or have a longer
> battery life.??
> Most of the camping will be with hookups, but occasionally we will
> DryCamp for a couple of days.
> Jack Smith
> 1973FC31
> SoCal
>

[jim riordan]

http://www.odysseyfactory.com/battspecs.html

This is what I use more power less space no water

Jack & Donna Smith wrote:

I need some info for the Batteries in our 1973 Gas Coach.. When we
bought it, there were 2 WalMart Maxx 29 Deep Cycle Marine Batteries,
875 cranking amps & 675 cold cranking amps. One was installed in the
front battery compartment by the drivers seat
& one in the Gennie
Compartment. I installed another of the same "Up Front", and another
under the entry steps, in the places provided. These are all 12V units.
Now they are about ready to be replaced.
Question is: Replaced with what?
My Coach is stored in a Storage area without connections of any kind,
and all the batteries have the knife type disconnect switches.
Would several 6V type be better for my use? AND WHY???
Also, is a smaller size battery, (of same cranking amps) any different
from a physically much larger unit.. Will the larger one have
more "Innerds" and last longer between charges, or have a longer
battery life.??
Most of the camping will be with hookups, but occasionally we will
DryCamp for a couple of days.
Jack Smith
1973FC31
SoCal

[Henry Jay Hannigan]

GPS Gary:
Regarding your article; You stated the following;

"The extra connections in a six volt system negatively impact
reliability and efficiency,"

On my two six volt Trojan T-105's, I have a "00" wire six inches long
connecting the negative and positive to make it 12 volts.

Please explain the "negative reliability and efficiency impact" of
this "extra connection."

Regards,
Hank
90SP36





--- In WanderlodgeForum@yahoogroups.com, "hippieforever3"
wrote:
>
> OK, first my bonafides.
>
> I have an electrical engineering degree and worked in quality and
> reliability in electronics over 30 years. While I'm not the world's
> foremost expert in wet storage batteries. I have had some
experience
> with the quality and reliability of "backup" electrical sources.
>
> ALL known types of rechargeable electrical storage devices
(batteries
> included) have "memory". The ability for the battery to absorb,
store
> and discharge energy is related to how much energy was stored and
> discharged in recent cycles. It's very much like flexibility in
> humans, if you don't slightly over stress your joints occasionally
> over time you lose flexibility. You can reduce failure and extend
> useful life by totally (over) depleting the battery bank once a
month
> or more. A perfect way to do this in an RV type application is to
run
> the air-conditioner until the batteries were clearly struggling
then
> turm on incandescent lights and leave them on for 6-12 hour AFTER
you
> can't see the filament glowing. Switch off all loads and use a good
> REGULATED low charge rate charger, not the alternator and
regulator.
> Actually a trickle charger would be perfect.
>
> Now this is not a very practical routine but the closer you could
> come to the deep, deep discharge and slow full, full charge the
> longer your batteries would last.
>
> In the most basic lead storage battery, the more lead the more
> overall storage capacity so in a crude sense the heavier the
battery
> the more ampere-hours, unless the weight is in the case not the
lead.
> While shear lead volume determines capacity from the standpoint of
> physics, performance is determined by configuration. The thinner
the
> lead plates are the faster they will charge or discharge (cranking
> power). The thinner the plates are the more the battery might be
> prone to failure from environmental factors like temperature and
> vibration. Here is the dilemma preventing you from picking the best
> battery using a scale.
>
> One really good indicator of battery quality is the case and
> terminals. Is the case a heavy thick walled rubber compound or is
it
> a nice thin walled high performance polymer? At the factory the
cost
> differential is at most $2. What they are charging retail is some
> indicator of value. If you can see the plate structure, what does
the
> workmanship look like? Check the materials of the terminals and the
> seals. On almost all batteries the top is a separate piece. Check
the
> joint construction and workmanship. ANY inconsistency or voids is a
> sign of lower quality craftsmanship. Check a couple of different
> sizes and cases from the same manufacturer.
>
> There is absolutely no inherent reason why 6 volt golf cart
batteries
> should be more capable of better handling numerous charge and
> discharge cycles than 12 volt batteries although the design of any
> battery will impact that and it may be a valid argument that
> batteries specifically designed for full charge / discharge
> applications will last longer. There are however 12 volt batteries
> designed for these same cycles and the extra connections in a 6
volt
> system negatively impact reliability and efficiency.
>
> As a general rule you should get better performance and life from
> sealed batteries. Typically they will be newer designs, often made
on
> more modern production lines and there is far less chance that the
> electrolyte will become (even slightly) contaminated or non-
optimal.
>
> Price vs. performance vs. reliability.
> Two $75 55ah 12 volt batteries will be more reliable than one $150
> 100ah battery but take up twice the space. You can limp in on one
of
> the $75 cheapies and with proper care ONE of them will last longer
> than the $150 battery. Will four $37.50 six volt batteries
outperform
> either of the other options ... Nope, if one of those four fail,
> you're walking.
>
> If you're looking at spending $500 or more on batteries, in a none
> emergency replacement, it might be worthwhile to contact the
> manufacturer and get the detail specs and reliability data on the
> models you are considering.
>
> Happy to help if you have questions.
>
> Regards,
> GPSGary
>

[Gardner Yeaw]

GPSGary,

If you deep discharge your lead acid batteries like you suggest you
will destroy them. That type of cycling is for Nicad and other types,
not lead/acid.

Gardner


--- In WanderlodgeForum@yahoogroups.com, "hippieforever3"
wrote:
>
> OK, first my bonafides.
>
> I have an electrical engineering degree and worked in quality and
> reliability in electronics over 30 years. While I'm not the world's
> foremost expert in wet storage batteries. I have had some
experience
> with the quality and reliability of "backup" electrical sources.
>
> ALL known types of rechargeable electrical storage devices
(batteries
> included) have "memory". The ability for the battery to absorb,
store
> and discharge energy is related to how much energy was stored and
> discharged in recent cycles. It's very much like flexibility in
> humans, if you don't slightly over stress your joints occasionally
> over time you lose flexibility. You can reduce failure and extend
> useful life by totally (over) depleting the battery bank once a
month
> or more. A perfect way to do this in an RV type application is to
run
> the air-conditioner until the batteries were clearly struggling
then
> turm on incandescent lights and leave them on for 6-12 hour AFTER
you
> can't see the filament glowing. Switch off all loads and use a good
> REGULATED low charge rate charger, not the alternator and
regulator.
> Actually a trickle charger would be perfect.
>
> Now this is not a very practical routine but the closer you could
> come to the deep, deep discharge and slow full, full charge the
> longer your batteries would last.
>
> In the most basic lead storage battery, the more lead the more
> overall storage capacity so in a crude sense the heavier the
battery
> the more ampere-hours, unless the weight is in the case not the
lead.
> While shear lead volume determines capacity from the standpoint of
> physics, performance is determined by configuration. The thinner
the
> lead plates are the faster they will charge or discharge (cranking
> power). The thinner the plates are the more the battery might be
> prone to failure from environmental factors like temperature and
> vibration. Here is the dilemma preventing you from picking the best
> battery using a scale.
>
> One really good indicator of battery quality is the case and
> terminals. Is the case a heavy thick walled rubber compound or is
it
> a nice thin walled high performance polymer? At the factory the
cost
> differential is at most $2. What they are charging retail is some
> indicator of value. If you can see the plate structure, what does
the
> workmanship look like? Check the materials of the terminals and the
> seals. On almost all batteries the top is a separate piece. Check
the
> joint construction and workmanship. ANY inconsistency or voids is a
> sign of lower quality craftsmanship. Check a couple of different
> sizes and cases from the same manufacturer.
>
> There is absolutely no inherent reason why 6 volt golf cart
batteries
> should be more capable of better handling numerous charge and
> discharge cycles than 12 volt batteries although the design of any
> battery will impact that and it may be a valid argument that
> batteries specifically designed for full charge / discharge
> applications will last longer. There are however 12 volt batteries
> designed for these same cycles and the extra connections in a 6
volt
> system negatively impact reliability and efficiency.
>
> As a general rule you should get better performance and life from
> sealed batteries. Typically they will be newer designs, often made
on
> more modern production lines and there is far less chance that the
> electrolyte will become (even slightly) contaminated or non-
optimal.
>
> Price vs. performance vs. reliability.
> Two $75 55ah 12 volt batteries will be more reliable than one $150
> 100ah battery but take up twice the space. You can limp in on one
of
> the $75 cheapies and with proper care ONE of them will last longer
> than the $150 battery. Will four $37.50 six volt batteries
outperform
> either of the other options ... Nope, if one of those four fail,
> you're walking.
>
> If you're looking at spending $500 or more on batteries, in a none
> emergency replacement, it might be worthwhile to contact the
> manufacturer and get the detail specs and reliability data on the
> models you are considering.
>
> Happy to help if you have questions.
>
> Regards,
> GPSGary
>

[Don Bradner]

As others have pointed out, there are some technical issues with your comments.
I think if you research the topic you will find a steady stream of "Lead-acid is
not subject to memory' on technical sites. Rule-of-thumb is to avoid discharge
below 50% whenever possible. I wouldn't personally go so far as to say a 100%
discharge will destroy a battery, but it will definitely shorten life.

One other issue is this part:
>Price vs. performance vs. reliability.
>Two $75 55ah 12 volt batteries will be more reliable than one $150
>100ah battery but take up twice the space

As you noted correctly "sheer lead volume determines capacity" so it is not
possible to have a 100AH battery that is the same size as a 55AH battery unless
the latter has an extreme amount of wasted space.

On 8/9/2008 at 12:44 AM hippieforever3 wrote:

>OK, first my bonafides.