Caravan house batteries

Radar · Guru

Caravan house batteries

Aus-Kiwi · Guru

I would use some type of solar . Either fixed or portable . Modern elect systems in cars dont totally charge Deep cycle batteries well . Dc2dc seems the way if no solar and travel nearly every day . Depending on usage .

Peter_n_Margaret · Guru

I recently replaced my AGMs from this Brisbane supplier.
www.batteryvalue.com.au/

I purchased 4 x 100Ah Newmax for the house plus 1 x 125Ah NPP as a crank battery.

The house is charged via solar but I can also charge quite effectively via the alternator direct.

Cheers,
Peter

-- Edited by Peter_n_Margaret on Tuesday 1st of September 2020 10:21:53 AM

Radar · Guru

Peter_n_Margaret wrote:
I recently replaced my AGMs from this Brisbane supplier.
www.batteryvalue.com.au/
I purchased 4 x 100Ah Newmax for the house plus 1 x 125Ah NPP as a crank battery.
The house is charged via solar but I can also charge quite effectively via the alternator direct.
Cheers,
Peter

Hi Peter and thank you. I will give them a call to work out what they can offer.

My thoughts only really, when I was talking with my lady this morning about the blue battery seems to be failing, I said I reckon that it maybe possible to run our caravan on say 120 AH only, our useage is fairly light, all led lights, mostly gas only, water pump a big draw at times and the new diesel heater for about 20 minutes of morning, tv is really limited used.

Maybe a lithium battery.

travelyounger · Guru

You could fit a dcdc charger in van and run a wire via Anderson plug from start battery and or run a solar panel through dcdc charger also to house battery
Cheers

Radar · Guru

Aus-Kiwi wrote:
I would use some type of solar . Either fixed or portable . Modern elect systems in cars dont totally charge Deep cycle batteries well . Dc2dc seems the way if no solar and travel nearly every day . Depending on usage .

Why would I use some type of solar?

I already have 340 watts on the caravan roof that has worked for 4 years.

Our modern car charges until the job done but this is not about charging.

And why would I want a dcdc expensive charger when the simple system I have been using 4years.

Looking for ideas for replacement batteries.

Radar · Guru

My first post must be confusing.

I am looking for good, better ideas for the replacement of our caravan house batteries.

Which is big lump sum to pay out but one that gives a good deal in the end at approx $100 @ year.

We are now using 2 batteries for 205ahs which is really overkill for our useage recharged by fixed 340 watts of solar.

The batteries are getting old and need replacing.

Any thoughts on battery/batteries.

Peter_n_Margaret · Guru

Radar wrote:
Peter_n_Margaret wrote:
I recently replaced my AGMs from this Brisbane supplier.
www.batteryvalue.com.au/
I purchased 4 x 100Ah Newmax for the house plus 1 x 125Ah NPP as a crank battery.
The house is charged via solar but I can also charge quite effectively via the alternator direct.
Cheers,
Peter
Hi Peter and thank you. I will give them a call to work out what they can offer.
My thoughts only really, when I was talking with my lady this morning about the blue battery seems to be failing, I said I reckon that it maybe possible to run our caravan on say 120 AH only, our useage is fairly light, all led lights, mostly gas only, water pump a big draw at times and the new diesel heater for about 20 minutes of morning, tv is really limited used.
Maybe a lithium battery.

You should be fine with 100Ah of AGM battery.

Apart from lower weight, lithium would not give you any benefits at all, but might mean you would need another solar regulator and charger.

A DC-DC charger would be useful in times of lousy sun.

Cheers,

Peter

Radar · Guru

Peter_n_Margaret wrote:
Radar wrote:
Peter_n_Margaret wrote:
I recently replaced my AGMs from this Brisbane supplier.
www.batteryvalue.com.au/
I purchased 4 x 100Ah Newmax for the house plus 1 x 125Ah NPP as a crank battery.
The house is charged via solar but I can also charge quite effectively via the alternator direct.
Cheers,
Peter
Hi Peter and thank you. I will give them a call to work out what they can offer.
My thoughts only really, when I was talking with my lady this morning about the blue battery seems to be failing, I said I reckon that it maybe possible to run our caravan on say 120 AH only, our useage is fairly light, all led lights, mostly gas only, water pump a big draw at times and the new diesel heater for about 20 minutes of morning, tv is really limited used.
Maybe a lithium battery.
You should be fine with 100Ah of AGM battery.
Apart from lower weight, lithium would not give you any benefits at all, but might mean you would need another solar regulator and charger.
A DC-DC charger would be useful in times of lousy sun.
Cheers,
Peter

I have an u bute charger that keeps company with the generater on the shelf in the shed.

But do believe a new 100 AH battery would be enough.

Just for a bit of a trial I may take the weaker of the 2 batteries out while I am at home and with all good news from our appointments we be off and on the road for another month. That should be a bit of a test to see if I only need one good battery.

Thank you

Aus-Kiwi · Guru

Radar wrote:
Aus-Kiwi wrote:
I would use some type of solar . Either fixed or portable . Modern elect systems in cars dont totally charge Deep cycle batteries well . Dc2dc seems the way if no solar and travel nearly every day . Depending on usage .
Why would I use some type of solar?
I already have 340 watts on the caravan roof that has worked for 4 years.
Our modern car charges until the job done but this is not about charging.
And why would I want a dcdc expensive charger when the simple system I have been using 4years.
Looking for ideas for replacement batteries.

Sorry I didnt read the part about your solar . yes your fine . If your happy with existing batteries ? Just get the same . I read it like your starting from

scratch . Sorry

Radar · Guru

Aus-Kiwi wrote:
Radar wrote:
Aus-Kiwi wrote:
I would use some type of solar . Either fixed or portable . Modern elect systems in cars dont totally charge Deep cycle batteries well . Dc2dc seems the way if no solar and travel nearly every day . Depending on usage .
Why would I use some type of solar?
I already have 340 watts on the caravan roof that has worked for 4 years.
Our modern car charges until the job done but this is not about charging.
And why would I want a dcdc expensive charger when the simple system I have been using 4years.
Looking for ideas for replacement batteries.
Sorry I didnt read the part about your solar . yes your fine . If your happy with existing batteries ? Just get the same . I read it like your starting from
scratch . Sorry

Thank you.

Whenarewethere · Guru

Radar wrote:
Which is big lump sum to pay out but one that gives a good deal in the end at approx $100 @ year.

& roughly how many kWh are you getting out of the batteries compared to grid supply?

You could even be in front!

travelyounger · Guru

Full river are a good heavy duty agm battery and are 120 amp they are approx 450 each at the higher end of the market or you could go to the middle of the market for around 350 each but shop around they can vary quite a lot in price for same battery and pretty sure the 105 amp are same size as 120 and some batteries up to 140 amp from Aussie batteries called Giant and getting around the 260 each but not sure on the quality maybe if any feedback on the Giant brand from anyone has them could help
Cheers

travelyounger · Guru

Full river are a good heavy duty agm battery and are 120 amp they are approx 450 each at the higher end of the market or you could go to the middle of the market for around 350 each but shop around they can vary quite a lot in price for same battery and pretty sure the 105 amp are same size as 120 and some batteries up to 140 amp from Aussie batteries called Giant and getting around the 260 each but not sure on the quality maybe if any feedback on the Giant brand from anyone has them could help Cheers

Radar · Guru

travelyounger wrote:
Full river are a good heavy duty agm battery and are 120 amp they are approx 450 each at the higher end of the market or you could go to the middle of the market for around 350 each but shop around they can vary quite a lot in price for same battery and pretty sure the 105 amp are same size as 120 and some batteries up to 140 amp from Aussie batteries called Giant and getting around the 260 each but not sure on the quality maybe if any feedback on the Giant brand from anyone has them could help
Cheers

The blue one is this brand, a couple of months younger by memory, the black one is generally about $80 cheaper but was hoping someone might give me another direction to go.

The agm batteries have my vote as time tested and is old school which works.

Thank you for suggestions.

Radar · Guru

Whenarewethere wrote:
Radar wrote:
Which is big lump sum to pay out but one that gives a good deal in the end at approx $100 @ year.
& roughly how many kWh are you getting out of the batteries compared to grid supply?
You could even be in front!

Whenarewe there hi.

You also miss my orignal post. Off Grid means we do not go on power in the caravan when touring.

I don't think my University double over trained Charter Account son could sit down and tell me if I am in front or not as to the costing.

We do not go into a caravan park and hook up to power.

Whenarewethere · Guru

Radar wrote:
Whenarewethere wrote:
Radar wrote:
Which is big lump sum to pay out but one that gives a good deal in the end at approx $100 @ year.
& roughly how many kWh are you getting out of the batteries compared to grid supply?
You could even be in front!
Whenarewe there hi.
You also miss my orignal post. Off Grid means we do not go on power in the caravan when touring.
I don't think my University double over trained Charter Account son could sit down and tell me if I am in front or not as to the costing.
We do not go into a caravan park and hook up to power.

No I didn't miss the point being off grid, but every X number of years batteries will have to be purchased & $100py in your case may be good value.

Back of the envelope we would use about the equivalent of $7.00 grid supply for a 3 month stint off grid for our 28L fridge & charging phone, camera & torches.

Aus-Kiwi · Guru

4 years vis not a long time . I wouldnt be very happy spending near $500 per battery for four years . Mine are the high end from
Battery world and 4 years old . Hoping
Not to jinx myself they are doing fine ! Maybe bay are drawing them down a little too far ? Do you have a VSR ( voltage sensitive relay) between starter and house batteries ? The extra assistance may help
?

Jaahn · Guru

travelyounger wrote:
Full river are a good heavy duty agm battery and are 120 amp they are approx 450 each at the higher end of the market or you could go to the middle of the market for around 350 each but shop around they can vary quite a lot in price for same battery and pretty sure the 105 amp are same size as 120 and some batteries up to 140 amp from Aussie batteries called Giant and getting around the 260 each but not sure on the quality maybe if any feedback on the Giant brand from anyone has them could help
Cheers

Hi smile

I have used Giant batteries from Aussie Battery and Solar twice. Been Ok and have one 140Ahr currently in our MH. Middle of the road cost / quality I think. Good heavy ones which is one thing to measure. The 140 is always well priced and free freight too.

https://www.aussiebatteries.com.au/

Jaahn

Radar · Guru

Aus-Kiwi wrote:
4 years vis not a long time . I wouldnt be very happy spending near $500 per battery for four years . Mine are the high end from
Battery world and 4 years old . Hoping
Not to jinx myself they are doing fine ! Maybe bay are drawing them down a little too far ? Do you have a VSR ( voltage sensitive relay) between starter and house batteries ? The extra assistance may help
?

But mine are coming up to 8 years old.

Technology has moved on.

Just looking for maybe better ideas.

Radar · Guru

Jaahn wrote:
travelyounger wrote:
Full river are a good heavy duty agm battery and are 120 amp they are approx 450 each at the higher end of the market or you could go to the middle of the market for around 350 each but shop around they can vary quite a lot in price for same battery and pretty sure the 105 amp are same size as 120 and some batteries up to 140 amp from Aussie batteries called Giant and getting around the 260 each but not sure on the quality maybe if any feedback on the Giant brand from anyone has them could help
Cheers
Hi
I have used Giant batteries from Aussie Battery and Solar twice. Been Ok and have one 140Ahr currently in our MH. Middle of the road cost / quality I think. Good heavy ones which is one thing to measure. The 140 is always well priced and free freight too.
https://www.aussiebatteries.com.au/
Jaahn

Jaahn hi.

We will be returning to our home base at the weekend, after unloading, cleaning the caravan. One of my first jobs is to disconnect the solar from our 2 batteries and then get them tested to much sure my thoughts on one failing.

Peter gave me good hint with the seller near home with batteries. Now your Giant Battery seems a good thing providing the 140 will fit in my battery case on the chassis.

Thank you for your thoughts.

woofta and precious · Senior Member

Hi Radar,

Just go for a drop in 120AH Lithium battery.

You have done pretty well camping off grid for 4 years with the setup you have, and with nearly 4000 posts, I would have thought you would be more aware of what's happening...

Radar · Guru

woofta and precious wrote:
Hi Radar,
Just go for a drop in 120AH Lithium battery.
You have done pretty well camping off grid for 4 years with the setup you have, and with nearly 4000 posts, I would have thought you would be more aware of what's happening...

The first 3808 post I was learning and unfortunately I am still enjoy learning and sharing information.

Kebbin · Guru

The Giant 140A battery has been discussed before and at 32.2kg for 140A It's tad light for an AGM, but I am not an expert, I understand weights are important with all batteries. It is said that 300g per amp/ 3kg per 10A for AGM's, Lithium are 1/2 that? According to some. Anyone have a formula for lithium batteries?

Peter_n_Margaret · Guru

There is no such thing as light lead.
A 140Ah AGM battery (at 20 hours - and that is an important part of the specification) should weigh about 42kg.
Cheers,
Peter

Whenarewethere · Guru

Light lead batteries are a composite of elements made from unobtainium & bullsh|taberyllium!

-- Edited by Whenarewethere on Wednesday 2nd of September 2020 10:39:21 AM

Hylife · Guru

for a grand you could now get 2x100ah LiFePO4 lithium drop in replacements giving you the equivalent of 400ah of old style lead acid.
Check out SolarKing from Low Energy Developments

www.solarking.net.au/batteries

www.lowenergydevelopments.com.au/batteries/LithiumBatteries

Peter_n_Margaret · Guru

Hylife wrote:
for a grand you could now get 2x100ah LiFePO4 lithium drop in replacements giving you the equivalent of 400ah of old style lead acid.

There is absolutely no reason why 100Ah can not be used from a 100Ah AGM. This so called 50% limit for AGMs is an urban myth.

100Ah is 100Ah irrespective of what the battery chemistry is, so that statement defies science.

Cheers,

Peter

darjak · Senior Member

Radar Could try Landplus batteries had two 130ah batteries approx $280 del
from Victoria to Beenleigh in 4 days. As far as keeping one dud battery with
the better one, dud one will kill the other one a known fact

Darjak

Hylife · Guru

Peter_n_Margaret wrote:
Hylife wrote:
for a grand you could now get 2x100ah LiFePO4 lithium drop in replacements giving you the equivalent of 400ah of old style lead acid.

There is absolutely no reason why 100Ah can not be used from a 100Ah AGM. This so called 50% limit for AGMs is an urban myth.
100Ah is 100Ah irrespective of what the battery chemistry is, so that statement defies science.
Cheers,
Peter

Science is exactly what that statement is all about, not myth at all, and how awful of you to suggest this.

There are plenty of visitors to this forum seeking genuine advice, and some that might possibly believe your bullsh!t recommendations.

All reputable battery manufacturers rate their batteries lifespan based on 50% depth of discharge.

Most Lead acid batteries are rated at around 5-600 cycles at 50%DOD and as little as 200 cycles at 80% dod .

Why at 50%? because the recommended capacity is over a 20 hour discharge period, and over this 20 hour period the voltage curve starts off quite steeply from full charge and gradually tapers off up to the 50% level, whereupon the voltage again decreases steeply

Hence the reason why most manufacturers rate lifecycles at 50% dod.

The correlation is that folks following the manufacturer's advice also suggest the 50%, but, you are right, in as far as you can ignore what the manufacturer suggests and can freely punish your batteries however you like.

Of course, that steep voltage curve past the 50% from lead acid progressively increases the current draw too, and is why well designed solar control devices and things like portable fridges have a low voltage disconnect hard coded at 11.8V, so that you don't unknowingly prematurely kill off your battery or damage the connected device.