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I know this subject has probably been discussed but \I cant find it anywhere using search so here goes. I have just had 5 wonderful days away over the new year and I took a spare battery with me as \I knew my 75ah would only last me 3 days max. The one I took was a car battery 45ah which lasted till we came home (just)

 

My question is this. .....I need a bigger storage capacity so it seems logical to buy 2 x 110 ah or bigger batteries and connect them both in the van so I wont need to mess around with hooking and unhooking batteries in the dead of night when its freezing and raining like it was when I changed mine this week.

 

Any tips on whats the best battery to get (my storage is quite big) and underneath the seats has a rack which can secure 2 batteries side by side anyway negating the need to store on the front nose adding weight to the nose weight. Ive been told to connect them a special way as parallel doesn't work and also what is the biggest ones I could go for as there are some 150ah van batts out there pretty cheap but they are not designated as leisure batts.

Im back to motorhoming with a scooter on the back again.

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Hi

 

I'm a motorhome and have two batteries as standard. They are 110 amp and are designated as leisure batteries. I don't know any more about them as they are standard equipment. I will ask a question though to "someone in the know"

 

Russell

Online blog and travels, although sometimes there is a lack of travel due to work!

 

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If I was going to do it . ...

 

Rather than getting 2 x 110 batteries i would get one of these

 

http://www. tayna. co. uk/SL200-Sonnenschein-Gel-Leisure-P3633. html

 

As its a sealed gell battery it would be a lot safer than a 2 xwet batteries.

 

I have seen them come up on e-bay from ex-motor home owners. ..

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Just to clarify something, parallel will work just fine, provided they are both the same size and same age. Also they need to be connected to the caravan supply with the same size and length of cable.

If there is any mismatch, as one goes flat, due to gradual ageing failure, it will draw charge from the other shortening the effective output of both.

The other issue is that the 'van charger won't be able to cope with them both at once, so you would need to disconnect them one at a time if you are planning to charge them this way.

Ssangyong Korando Sports SX / Adria Altea 472DS Eden

 

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Unless you have a sealed area with ventilation to the outside its not a good idea to have wet lead acid batteries inside the van due to explosive gases etc, that said - it's not impossible to create a safe area to house two batteries that are connected in parallel if you want to do the work.

 

Alternatively there are totally sealed gel batteries available but they are quite pricey.

 

If you do create a larger battery locker you need dedicated leisure batteries that are designed for deep cycling, cheap engine start batteries will get knackered, leisure batteries are designed to provide a certain amount of power over a given time (the ah rating) and be used for continuously charging and discharging (not completely flattening though by the way).

 

You do want to connect them in parallel, connecting them in series will give you 24v, I expect someone has mentioned that there is a right and wrong way to connect them in parallel in order to get an even charge/discharge from both batteries, there is a link below to a page that describes how to do this.

 

http://caravanchronicles. com/guides/how-to-connect-two-batteries-in-parallel/

 

On the subject of charging, you will need a charger capable of charging a 220-300 ah battery bank, I suspect that most chargers fitted as standard to vans will not have enough oomph to cope so you may have to upgrade your charger, wouldn't cost the earth but needs considering.

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I should add, additionally re: mounting them.

Ideally they should be securely mounted in an enclosure sealed from the caravan, but vented to the outside to allow gasses produced when charging to escape.

If you are not planning to charge them in situ, you could get away with mounting them in a locker and fitting a venting tube to the provided hole on the battery into a gas drop hole vent.

The amount of gas produced simply taking power from the battery is practically negligible, unless you are drawing a massive amount of current.

Ssangyong Korando Sports SX / Adria Altea 472DS Eden

 

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The batteries will need venting where ever they are positioned and they should not be fitted in the front gas locker .

 

I use 2x 185 amp batteries in parallel in one of my trailers but I think you will need to check the amount of added weight batteries add .

 

Have you considered a battery box and a split charge relay in the boot or a couple of wires connected to the towing socket to plug in the car when you go out to charge the battery ?

 

 

Dave

Jeep Commander 3. 0 V6 CRD

Isuzu D- Max Utah Auto

Elddis Crusader Storm 2000 Kgs, Unipart Royal Atlas Mover .

 

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You'd probably be best fitting one in battery compartment and one elsewhere with a big fat changeover switch arrangement for simplicity. Fused and cabled appropriately. TBH the current draw/charging input is not that high so it shouldn't be that costly.

 

Others have mentioned other factors. .. DO read the battery faq I keep linking to as it is a wealth of useful information.

 

Weight of the extra battery and cables will have to be deducted from your payload.

 

May be worth considering a way to carry the 'other battery' in the car so as to be able to recharge it (partly) if 'touring' in the area you are caravanning??

2012 Bailey Pegasus 2 Rimini towed by 2019 Ford Galaxy Titanium X, 2.0 EcoBlue, 8 speed auto.

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The sealed gel batteries are very good. I used one for years in my old van. I used this off grid often, but no TV then, just for lights and pump. I aquired it when the company I worked for closed and we had several spare as they were fitted to good quality electric mobility scooters

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I will be charging them off the van at home when needed as I never do EHU. I also have a solar panel on the van so when on the van the panel can do the work and hopefully keep them topped up in the summer. I take it that a solar panel can still charge them in parallel connected the right way with feed from one and earth from the other as suggested above.

Im back to motorhoming with a scooter on the back again.

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Hi I have 2 x 115 batteries fitted to my van and also have a solar panel fitted to the roof panel is 80w both batteries need to be the same size and the same age as one will take power from the other. I have used this system with out bother for about 5 years if plugged in to the mains the caravan charges the batteries fine. I have camped up to 4 weeks with no bother, I do remove batteries once a year a charge fully.

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I know this subject has probably been discussed but \I cant find it anywhere using search so here goes. I have just had 5 wonderful days away over the new year and I took a spare battery with me as \I knew my 75ah would only last me 3 days max. The one I took was a car battery 45ah which lasted till we came home (just)

 

My question is this. .....I need a bigger storage capacity so it seems logical to buy 2 x 110 ah or bigger batteries and connect them both in the van so I wont need to mess around with hooking and unhooking batteries in the dead of night when its freezing and raining like it was when I changed mine this week.

 

Any tips on whats the best battery to get (my storage is quite big) and underneath the seats has a rack which can secure 2 batteries side by side anyway negating the need to store on the front nose adding weight to the nose weight. Ive been told to connect them a special way as parallel doesn't work and also what is the biggest ones I could go for as there are some 150ah van batts out there pretty cheap but they are not designated as leisure batts.

Before getting into the complexity and weight of 2x batteries I'd try getting a new 120Ahr, or bigger if you have the space in the battery locker and see how you get on with that.

 

If that dosent do the trick you could then get a second battery and fit quick release clamps so swapping out was quicker/easier. Don't wait until its discharged completely, swap out when its 'on the way out' and its convenient to do so, during the day, when its not lashing it down. ..

 

The other solution is to reduce your power consumption, you could swap out regular bulbs for LED. A regular bulb could be consuming 10-20W of power an LED of similar light output would be 1-3W, potentially a significant reduction as the lights are likely to be on for long periods of time especially in the winter.

 

Do you use a 12v TV? Thats likely to be quite a power drain.

 

I can go 5 to 6 days on a 110Ahr battery in the summer, but we don't use a TV.

 

Get a cable a run the caravan 12v off the car, your fridge might not work even on gas in the config due to the way the socket is wired - this can with a bit of DIY be fixed.

Unicorn IV Cartagena 2019my | Mercedes-Benz GLE350d (W166)

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missbusybusy is correct deep cycle forklift, milk float, golf trolley, mobility scooter, or wheel chair batteries would be better. But also batteries in parallel will need more looking after there is a tendency to get unequal cells so although gel may seem a good idea being able to top up is also important. Many years ago I had the same problem and my cure was to charge in the car. I used a plastic bread bin to hold the battery and had some straps in the boot to ensure it was well fastened down car spit charging recharged the battery on days out and when one battery was flat it was swapped with spare car one. Weight is a problem so around 60AH so easy to carry. Using gas lights etc the battery would last around 5 days between swaps.

Today we have lost gas lights but we have gained inverters. Battery to battery chargers were not around all those years ago so charging a battery from flat in the car was slow. Today battery to battery chargers are made by Gordon Equipment (Durite) and Sterling the latter designed for charging bow thruster batteries in a boat. Clipping on an ammeter in the old days at start it would show 25A but within 5 minutes this was down to around 5A and so a 15 minute run to the shops would likely put around 3AH into the battery.

 

However the new battery to battery charger uses three stage charging so although only 10A likely whole trip at 10A so 5AH into the battery. Unlikely you will drive far enough to fully re-charge battery you will just extend their lives.

 

Next is the lights. I have been amazed at home of how good LED lighting is. I have swapped 11W cold cathode spot lights for 2W LED and they are brighter. So first move has to be all LED lighting.

 

If using old style split charging in the boot it does work far better than in the van. The volt drop on cable is far less. Come back gas lights all is forgiven!

 

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The amount of gas produced simply taking power from the battery is practically negligible, unless you are drawing a massive amount of current.

 

 

Isn't hydrogen only produced during charging?

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Alternatively there are totally sealed gel batteries available but they are quite pricey.

 

No batteries are totally sealed. Many batteries, including gel and AGM, are Valve Regulated Lead Acid with a relief valve to vent off gas

 

 

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Just to clarify something, parallel will work just fine, provided they are both the same size and same age. Also they need to be connected to the caravan supply with the same size and length of cable.

If there is any mismatch, as one goes flat, due to gradual ageing failure, it will draw charge from the other shortening the effective output of both.

The other issue is that the 'van charger won't be able to cope with them both at once, so you would need to disconnect them one at a time if you are planning to charge them this way.

 

Same size is irrelevant, same age possibly, cable length pretty much irrelevant and the caravan charger will be fine.

 

RT

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No batteries are totally sealed. Many batteries, including gel and AGM, are Valve Regulated Lead Acid with a relief valve to vent off gas

 

Well yes but some are marketed as totally sealed in the sense that unless you abuse them they are. Is fairly common in the marine environment for gel or agm to be fitted in what would be called the living environment without too much concern.

 

As this bit of info states, "VRLA batteries offer several advantages compared with flooded lead–acid cells. The battery can be mounted in any position, since the valves only operate on overpressure faults. Since the battery system is designed to be recombinant and eliminate the emission of gases on overcharge, room ventilation requirements are reduced and no acid fume is emitted during normal operation. The volume of free electrolyte that could be released on damage to the case or venting is very small."

Concorde state that their batteries are suitable for enclosed aircraft spaces as even on overcharge the amount of gas produced is less than the 4% limit.

 

I take your point but the risk is quite a bit less than having two wet batteries under the bed

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I have a 110ah battery and find I have plenty of power, during summer its fully charged by mid morning with a 50w panel (takes longer during winter).

When I had the crt tv & a freeview box I had an 85ah as a second battery just for the tv, this battery was wired direct to the tv.

 

Since buying the 12v traveler tv I only use the 110ah battery & a 50w panel, the tv is coupled direct to the low volt disconnect on the controller, my 85w tv battery and my 2x20w second panels are redundant.

 

Thinking along those lines is there anyway you could reduce power consumption (leds etc) or could you use a second battery for the most power hungry item.

I have a 110ah Lion calcium leisure battery, a 50w kyocera panel & a morningstar sunsaver controller

Paul B

. .......Mondeo Estate & Elddis Avanté 505 (Tobago)

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Whilst I don't necessarily recommend this, I underestimated the effectiveness of my solar system (in winter) and due to the cold weather and the central heating pump being on a lot, I quickly ran out of charge. My 110AH leisure battery was only lasting two, maybe three days. No EHU so I had to improvise. I'm currently topping up every few days by running an inverter from my tug.

 

I'm just saying that a two battery solution isn't the only solution available to you.

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I'm currently topping up every few days by running an inverter from my tug.

 

 

I'm sure it won't work otherwise every van would have one - but in non technical language can someone explain to me why you can't have an inverter running off the battery which is then used to power a battery charger - I guess it's a bit like perpetual motion and it won't last - but what gives up first, the power to run the inverter or the power needed to charge the battery?

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You could but you would drain the battery more than you'd charge it due to losses in the conversion (heat, sound, magnetic coil losses, component leakage to mention but a few). For example, the charger would provide 8A @ 13. 8V (110W) into the battery but would require 0. 7A at 240V (168W) to produce that.

 

Most inverters come with a battery under-voltage cut-out - to prevent completely discharging a battery (which is bad). I would say the inverter would give up first. Hypothetically speaking!

 

I'm fitting a new inverter this evening so hopefully I'll be able to have full EHU supply, albeit from my car. To those wincing at a car being used like this, I know! ;) Its just a stop-gap until I can afford a proper genny.

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Same size is irrelevant, same age possibly, cable length pretty much irrelevant and the caravan charger will be fine.

 

RT

Sorry but no I have had problems with faulty cells in one battery dragging down another battery in parallel. This is a common problem with the narrow boat people who will carry tons of batteries in the hope of getting them charged while at a marina and then them lasting until next time at a huck-up.

 

Again cable length again with a boat this time during the building of the second 7 crossing were having big problems all because the cable length blocking diode to battery were not all the same and blocking diodes were burning out.

 

I think tictag's idea of using an inverter to charge is sound. The problem with jump leads is the battery voltage is limited to around 13. 8 volt or whatever the car alternator is set at and very quickly the battery will just not accept charge from the car. However with an inverter the charger voltage is with a three stage charger more like 14. 8 volt so the speed of charging will be faster although this is very dependent on the caravan battery size and the inverter and stage charger size.

 

I tried to charge a mobility scooter while in the car and day one all worked great. However next day when a little further and it failed. The inverter was too small once the charger went off float charge.

 

So an inverter like this http://www. thetoolboxshop. com/0-852-52-durite-12v-dc-to-12v-dc-20a-split-charger-4781. html?gclid=CIXTjoXb7LsCFZPItAodvXcAaQ will work better than simple jump leads. But a 150W inverter supplying a charger like this http://www. bykebitz. co. uk/c-tek-xs-0-8-battery-charger. html?gclid=CP-_tNDb7LsCFUzHtAodkCwAiA is a complete waist of time a simple good set of jump leads would do a better job.

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A change-over switch to enable the use of the 2 batteries as suggested by Rodders is an solution that we used to use years ago in ships for emergency lighting etc (they probably still do). Another less technical way to utilise 2 batteries is to fit the batteries via 2 suitably positioned switched sockets, one for each battery. The van (load) can then plugged in to one of the 2 sockets as required without going outside the van. Using the batteries individualy in this way is probably a safer and easier to manage option than running the batteries in parallel.

 

Have you considered a van to car power lead. I carry one for emergency van power but in the days of my 1980 Super Muskateer we used to be off grid for a month at a time (using lights only though), providing the car was used regularly we never had a problem apart from when we used to drive of without disconecting first.

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A point of information, most modern cars have the alternator set at around 14. 4v, not 13. 8v as it was a long time ago. You tend to see less down at the towing socket(s) because of wire length. That said, the very latest cars sometimes have variable charging voltages to improve efficiency. They up the alternator output when you are braking, lower it (sometimes to not charging at all) when there's not spare energy. It's kind of like KERS in F1 cars.

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