Battery/power issues

[JTQ]

Our batteries in real terms can store a very limited amount of energy, so buying bigger only ends up buying a little bit more of what is always small capacity. Actually with many technologies including LA, even that is 50% of its labelled value, then in its first flush of youth.

The logical way is to store what you need in the short term and keep refilling it, be that via a hookup. solar or your cars alternator, rather than try to store increasing amounts.

 

[Buckman]

AGM batteries benefit from a special charging routine, that may not be an optional setting in the likely budget chargers often fitted in caravans.
Unless you know your charger has that option, it's a "dear" choice, therefore buying one is a near zero benefit battery choice.
Like many things its "horses for courses", well worth while if on the right course, a poor choice if not.

A way around the onboard charger is to buy a Noco Genus charger that handles LA, AGM, Lithium etc. and yo use that to recharge the battery. A decent solar panel with the correct controller can recharge the battery whether AGM or lithium when off grid.

The big advantage is of course that if upgrading the caravan at some point in the future, the battery and charger can be taken to the newer caravan. I would suggest a standalone solar panel instead of a fixed panel until they have upgraded.

 

[JTQ]

Clearly you can buy any number of suitable chargers, but why not simply buy a battery of a type matched to what exists?

It did not come across to me our assistance was asked on advising on optional solutions irrespective of costs, more something reflecting a limit budget mobile accommodation set up.

 

[Anseo]

Some observations:

The word lithium appears to be used in the generic sense for more than one type of lithium related battery, it is important for safety purposes, for charging regime purposes and for several other reasons that the choice of battery type should be specific.

In brief:
e.g. Lion (lithium ion) is not as safe in use as LifePo4 (lithium iron phosphate), if making a choice then LifePo4 is superior to Lion for many reasons.

For various reasons as given by the OP I can only recommend LifePo4 as being the best choice overall.

LiFePo4 batteries do not require venting or require special enclosures.

The various 'Lithium' battery types have different charging requirements making the choice of battery charger very important.

Lion and LiFePo4 characteristics


Battery charging:
The existing battery charger can be replaced using a modern smart charger, there are many to choose from; CTEK has a good reputation (I happen to have one and I like it very much), however I can also recommend both the Noco Genius 5 and the Noco Genius 10 (again I have both and am very pleased with them).

The Noco Genius 10 (10 amps as opposed to 5 amps for the Genius 5) would be more appropriate on a 100 Ah battery, there is a cost disadvantage over the Genius 5, the Genius 5 will do just as good a job albeit more slowly.

Dimensions and weight of battery:
LifePo4 batteries can be housed in cases that have smaller dimensions than traditional lead acid batteries, it is worth checking the various manufacturers data sheets, LifePo4 is approximately half the weight of conventional lead acid batteries.

Where there are strict limitations on space then there are now options for "Mini" 100 Ah LiFePo4 batteries, there may be a cost cosideration. LiFePo4 battteries have come down a lot in price and prices continue to fall.

For standard (non mini) sized LiFePo4 batteries, there is much competition, it really makes lot of sense to shop around and do your research as to what is best for you, prices can vary considerably for what is essentially the same product.

e.g. Mini example 1
Mini example 2

Positioning and location of LifePo4 batteries:
LiFePO4 batteries can have several mounting positions. While these batteries are commonly mounted vertically, horizontal and side mounting orientations can also be considered (refer to manufacturers data sheet).

Charging the battery off-grid:
I have just recently moved from rigid solar panels to portable and flexible solar panels housed in a home made lightweight adjustable frame (32mm plumbing waste pipe).

For LiFePo4 a solar charge controller with LiFePo4 setting is necessary,
fortunately these are no longer expensive.
Portable panels give significantly superior solar harvesting results compared to rigid panels that are usually in a fixed location, i.e. the roof.

LiFePo4 batteries, solar charge controllers and portable solar panels can be taken with you to different locations or transposed to another vehicle\caravan.

 

[Anseo]

I am fairly sure that there should be no issue with the AGM battery. The lithium may require a charger upgrade.

For the first sentence you are therefore "unsure".
For the second sentence, again you do not know.

Please try to avoid giving misleading comments, potentially dangerous comments at that.

Using the wrong chargers can have serious consequences in terms of user and equipment safety.

EDIT: I meant to add this link , my bad, oops and apologies.

 

[trevormonty]

If upgrading use LiFePO4 will be more expensive but lot benefits.
1) Save to use cabin as they don't need venting. Best to buy quality $$$ brands for this reason.
2) Higher storage capacity as it can be discharged to 20% on regular basis. With AGM going below 50% will shorten their life considersbly. As comparsion on a 100AHr battery that is 80AHr vs 50AHr of useable capacity.
3) Long life, will last >3 times longer especially if doing deep discharge cycles.
4) Very light 12kg vs 28kg for 100Ahr battery. If you fit Anderson connectors to battery cable then only takes few seconds to unplug and remove for storing and charging at home. That 16kg weight saving also counts towards your user payload.
5) Option to have BT connectivity with your phone so you can monitor battery state. Only avaliable on more expensive batteries.

Some brands do a drop in replacement for AGM and can be used with existing charger. My recommendation is budget on new LiFePO4 charger.

Battery and charger are a investment so plan on keeping them for next caravan. Don't throw out old charger as you can renstall it with a 60AHr AGM battery when selling van.

While it is recommended you use AGM battery in vented locker the outgassing is very minimum in standard use. Being sealed batteries they don't out gas unless over charged and heavily discharged.

 

[trevormonty]

There is 3rd option to but won't work in your case as you have motor movers and they really need fixed battery that can deliver high currents.

Portable power stations. These contain LiFePO4 battery, with inbuilt solar, 12v and 230V charger. Inverter (230V output), USB and 12V outputs. Not as expensive as they may seem, by time you buy fixed battery, 230V charger, solar charger which has to been wired in and inverter (optional), they may work out cheaper.
Being portable can be removed for charging by 230V, 12V(car cigarette lighter), portable solar panel.

The limited 12V 10A output should be enough to handle lighting and controller needs of older caravan especially if upgraded to LED lighting. Probably not enough for newer caravans with central controller that drives everything.

 

[Hutch]

The AGM will need to be vented to the outside and as mentioned a simple pipe, but an AGM battery should fit into the current locker. The lithium may require a change of charger due to age of the caravan. You will need professional advice on the latter. We had a 2004 Lunar with a 100ah battery.

I have a couple of AGM batteries, motorcycle, and mobility scooters, and also a 90 amh. One for my Santa Fe and non of them are vented , the documentation that comes with the smaller batteries state they can be fitted in any orientation ie side ways etc. no vent pipes.

 

[ProfJohnL]

Just a word of caution, Whilst Hutch may have two AGM batteries that do not need ventilation, don't assume that will apply to all makes and models. Check and follow the fitting instructions of the model of battery you ultimately go with, or deliberately make non ventilation a criteria to check for.

 

[Buckman]

I have a couple of AGM batteries, motorcycle, and mobility scooters, and also a 90 amh. One for my Santa Fe and non of them are vented , the documentation that comes with the smaller batteries state they can be fitted in any orientation ie side ways etc. no vent pipes.

I thought the same with the Bosch AGM in the Jeep, but it is definitely vented to the outside. I would think that on a motorcycle or mobility scooter there would be no need to vent to the outside? No venting for the AGM Yuasa battery in the caravan as that is in its own locker and cannot see anywhere to connect a venting pipe?

 

[ProfJohnL]

I thought the same with the Bosch AGM in the Jeep, but it is definitely vented to the outside. I would think that on a motorcycle or mobility scooter there would be no need to vent to the outside? No venting for the AGM Yuasa battery in the caravan as that is in its own locker and cannot see anywhere to connect a venting pipe?

That's why you have to review the instructions for each model of battery you might consider. Just becasue one model may not provide venting does not mean its the same for all.

 

[trevormonty]

If all AGM have that vent available without me trawling the Internet, I'm fine venting it, that may be my easier option.

I was thinking about feeding a battery charger in using the 240v socket anyway, but I'm unsure about how to "disable" the caravans inbuilt charger so put that one on hold

There is most likely existing vent in floor nearby. Most caravans have few floor vents in cabinets and under beds, have look around. Don't block them as they let van breath and prevent mositure buildup.

What is a AGM Battery?

AGM batteries are a type of sealed lead-acid battery using "Absorbed Glass Mats" between the plates. This is a very fine fibre boron-silicate glass matting. Electrolyte (acid) is fully contained in the glass matting and will not spill, even if br...

support.rollsbattery.com

 

[otherclive]

There is most likely existing vent in floor nearby. Most caravans have few floor vents in cabinets and under beds, have look around. Don't block them as they let van breath and prevent mositure buildup.

What is a AGM Battery?

AGM batteries are a type of sealed lead-acid battery using "Absorbed Glass Mats" between the plates. This is a very fine fibre boron-silicate glass matting. Electrolyte (acid) is fully contained in the glass matting and will not spill, even if br...

support.rollsbattery.com

Hydrogen rises so if a vent is required it should be positively piped to the outside.

 

[ProfJohnL]

...
I was thinking about feeding a battery charger in using the 240v socket anyway, but I'm unsure about how to "disable" the caravans inbuilt charger so put that one on hold

The onboard charger will have some form of 230Vac isolator so you can choose to have it turned on or not, it will also most likely have an output fuse which you might be able to remove.

I note from your supplied photo, there is a 12 V switch on top of the charger, but I don't know if that is a switch that disconnects the habitation circuits or just the charger.

 

[JTQ]

AGMs, Gels etc whilst termed "sealed" are not sealed but valve regulated; [VRLA] save making a potential "bomb" out of them.

Edit: Wiki gives way more info LINK

 

[trevormonty]

Hydrogen rises so if a vent is required it should be positively piped to the outside.

Best idea is see how european caravans deal with this issue as they quite often place battery under bed or seat. Definitely no piping or venting arrangement in my Adria. Its in splashproof plastic battery box under bed. I assume this factory installation based on how straps and wooden guides for box are fitted.

 

[otherclive]

Best idea is see how european caravans deal with this issue as they quite often place battery under bed or seat. Definitely no piping or venting arrangement in my Adria. Its in splashproof plastic battery box under bed. I assume this factory installation based on how straps and wooden guides for box are fitted.

So why the red herring of your previous post and the discussion on venting relying on the floor level vents? It’s just a physical property that hydrogen rises and dissipates rapidly if not contained.

 

[toad a caravan]

the consumer shown in the image looks like a PMS .It is fitted with a 12v rocker switch that illuminates orange when charging.. I'm rather surprised that a 2000 caravan is using a similar unit as my 1992 caravan (PMS 1)