Another battery thread

[REC]

Ok, please be gentle with me.
We need to replace our leisure battery (which is under the driver's seat). Thinking about a lithium so that we have less weight and more capacity but this is where my knowledge ends! Have tried reading old posts but my brain goes. If we just replace the AGM we have with another, it is straightforward. Can we just do the same with a lithium...keep reading about b2b chargers ...I know there is a charger already in the setup and we have a solar panel connected which has a controller. Don't want to end up having to replace lots of bits as patently don't understand it!
Can someone explain in simple words if we can just do a straight swap... The only thing which has sunk into my brain is that the charger has to be limited to 14.4max?
Thanks and sorry!

 

[Pudsey Bear]

If the old one has always done what you need, just swap like for like, get the code of the existing one and get one delivered to your home.

 

[Canalsman]

However if you wish to reduce running costs and increase reliability and performance installing lithium is a better option.

More information is needed regarding the existing charging system. What make/type of solar regulator is installed? If the other charging is done by the original manufacturer's installation the make/model/age of the 'van will identify the likely charging system already in situ.

 

[barryd]

Read all 52 pages of this.

Hank the Tanks Dodgy battery and solar system

Well it's been virtually a week since we arrived off grid here in south Dorset in the new van with the untested solar and battery. Bit of a development last night. It all went a bit pear shaped. I figured something was up Friday night when after three days of sun the Swift control panel was...

wildcamping.co.uk

To summarise a year long thread (almost) IMO if what you had did a good enough job or nearly a good enough job its a lot cheaper and less hassle to replace like for like or just make a few improvements. Lithium is not a "drop in" replacement and as it "appears" to have turned out for my use (see thread towards the end) overkill. For now at least. In the end instead of spending £3k on an all singing and dancing lithium and solar upgrade I did the next best thing with 2 x 120ah lead acids, an extra solar panel and a Victron Smart solar controller for about £350 but I did have a lot of help.

 

[REC]

However if you wish to reduce running costs and increase reliability and performance installing lithium is a better option.

More information is needed regarding the existing charging system. What make/type of solar regulator is installed? If the other charging is done by the original manufacturer's installation the make/model/age of the 'van will identify the likely charging system already in situ.

It was a professionally converted panel van done in 2018.
The controller is a photonic universe Tracer MPPT
Solar panel is 160

 

[merl]

Can someone explain in simple words if we can just do a straight swap.

In general lithium is easier to charge than lead acid, it's not particularly fussy.
Drop in lithium is possible but due to technicalities which I won't go into here it's typical to install a battery to battery charger too.
If you're existing Solar charge controller doesn't have a dedicated lithium profile then it's often possible to get by by using the Gel setting or a user defined setting. Same with the onboard mains charger.
KS energy do a lithium battery that's built with oddball cells, they claim.its 'drop in compatibe' but it's expensive and you could buy a cheap lithium AND a B2B for less but you'd have to add installation costs too.
Consider the maximum battery size in under seat situations

 

[merl]

I did have a lot of help.

And cider

 

[REC]

Our battery is too small and is just not big enough for the job. Twice on the trip home, we had no electric and had to get ehu. The battery was brand new before the trip, although we suspect it had "been on a shelf" for a long while. As it was bought in a hurry and had to be a specific size we didn't shop around much. We have to get one which will fit under the seat still... the van really has no other place to site it now without major works.. two batteries would not fit. Seen several sites which say that their battery can be "dropped in" but remember the threads with all that is involved! Even saw one site which said that b2b chargers were unnecessary and overkill ...(whatever a b2b is!)
Did try and read the above thread but it got a bit technical and I gave up! We only want the exchange battery as probably will sell the van next year as Dave is finding the driving more difficult now with eye problems. ....

 

[REC]

The controller we have says there is a lithium setting and the charger is set for gel....so the b2b thing is the issue? I have the exact measurements of space under the seat .

 

[Canalsman]

b2b is the acronym for Battery To Battery charger. This is fitted frequently in conjunction with a lithium battery installation and piggy backs off the starter battery.

When the engine is running and the alternator is charging the starter battery the B2B makes the alternator think it needs to continue charging even though the starter battery is charged. That current is diverted to the lithium battery to charge it at a high charge rate.

The effect is to recharge the lithium battery quickly and with the need for relatively little driving.

Your 'van at present probably has a basic split charge relay system which in simple terms charges both starter and leisure battery at the same time but at a much slower rate than achieved with a B2B.

What you probably need to do is to find a lithium battery that will fit where the existing lead acid battery fits, change the setting on the solar regulator and ideally install a B2B.

I'm sure @wildebus and @Admin will be along shortly to advise more fully.

 

[wildebus]

Our battery is too small and is just not big enough for the job. Twice on the trip home, we had no electric and had to get ehu. The battery was brand new before the trip, although we suspect it had "been on a shelf" for a long while. As it was bought in a hurry and had to be a specific size we didn't shop around much. We have to get one which will fit under the seat still... the van really has no other place to site it now without major works.. two batteries would not fit. Seen several sites which say that their battery can be "dropped in" but remember the threads with all that is involved! Even saw one site which said that b2b chargers were unnecessary and overkill ...(whatever a b2b is!)

Did try and read the above thread but it got a bit technical and I gave up! We only want the exchange battery as probably will sell the van next year as Dave is finding the driving more difficult now with eye problems. ....

If you are selling in a years time, IMO there is no point in overcomplicating the situation by going Lithium, adding a B2B, adding a reliable battery monitor, having to add in extra cabling, pay for installation of all the above, etc.
All the above can be worthwhile for sure but not for a single season of enjoyment.
What I would do is get the best lead battery that will fit in the space. Go for a GEL or AGM battery and these can be fitted on their side, which may give you more options rather than choosing one with the right height to fit. A Lead Carbon type tends to give better performance and can be abused more without a problem.
You could possibly consider getting a power bank and then take it out when you sell the van and sell it on maybe? get some benefits of Lithium and inverter without expense of installation

 

[Pudsey Bear]

Read all 52 pages of this.

Hank the Tanks Dodgy battery and solar system

Well it's been virtually a week since we arrived off grid here in south Dorset in the new van with the untested solar and battery. Bit of a development last night. It all went a bit pear shaped. I figured something was up Friday night when after three days of sun the Swift control panel was...

wildcamping.co.uk

To summarise a year long thread (almost) IMO if what you had did a good enough job or nearly a good enough job its a lot cheaper and less hassle to replace like for like or just make a few improvements. Lithium is not a "drop in" replacement and as it "appears" to have turned out for my use (see thread towards the end) overkill. For now at least. In the end instead of spending £3k on an all singing and dancing lithium and solar upgrade I did the next best thing with 2 x 120ah lead acids, an extra solar panel and a Victron Smart solar controller for about £350 but I did have a lot of help.

Not forgetting the high-priced Gizmott Barry.

 

[oppy]

We have 3 proper batteries that do everything that we need connected to a 120 solar panel and the 3 of them probably cost less than one of these new fangled ones !!

 

[trevskoda]

We have 3 proper batteries that do everything that we need connected to a 120 solar panel and the 3 of them probably cost less than one of these new fangled ones !!

You could easy do with another same size panel for shorter dull days, im running180ah battery and 200w solar. nov dec is the weekest time of the year.

 

[molly 2]

If you are selling in a years time, IMO there is no point in overcomplicating the situation by going Lithium, adding a B2B, adding a reliable battery monitor, having to add in extra cabling, pay for installation of all the above, etc.
All the above can be worthwhile for sure but not for a single season of enjoyment.
What I would do is get the best lead battery that will fit in the space. Go for a GEL or AGM battery and these can be fitted on their side, which may give you more options rather than choosing one with the right height to fit. A Lead Carbon type tends to give better performance and can be abused more without a problem.
You could possibly consider getting a power bank and then take it out when you sell the van and sell it on maybe? get some benefits of Lithium and inverter without expense of installation

That's exactly what I did , fited lead carbon ,battery, bought a blueti 1800 a lightweight 200w portable solar panel ,no alterations van electrics and I can use my microwave of grid

 

[mark61]

2018 conversion, on a 2018 van?
Isn't there a good chance that has a smart alternator and a reasonable chance has a B2B too?

 

[RichardHelen262]

I have also been looking to see if I could just swap my battery to a lithium,
Roamed batteries say that their batteries can be a straight swap, they are a bit more expensive, but if you don’t have to buy a load of other items to make it work then it could be a cheaper option in the long run

Roamer - Premium LiFePO4 Lithium Leisure Batteries Campervans & Boats

"Roamer SMART4, XTREME & HOME: 12V-48V LiFePO4 leisure batteries for campervans, motorhomes & boats. 100Ah-460Ah, Bluetooth BMS, 10-year warranty."

roamer.com

 

[barryd]

Do you know what AH (Amp hour) the current battery is? If you are selling next year its pointless spending a lot of money on a Lithium set up and if you get it professionally done it will be a chunk of money. I would be looking to see what is the largest battery I can fit in the available space and just swapping it out for that. I believe the lead carbon Gel Batteries are the next best thing to Lithium and "I think" they are just a drop in.

If your current battery is say a 90ah or a 110ah can you fit a 160ah lead carbon battery in? Alpha Batteries (who we have a discount code with I think) do several. You would need to see what will fit though.

https://www.alpha-batteries.co.uk/leisure-batteries/?filter_ab_construction=lead-carbon-gel

The other thing that @merl on here taught me is that cable sizes are important. In particular I think from the solar controller to the battery. Might be useful for you to start posting some photos of all that and your set up so the experts can advise. If you dont use thick enough cables you don't get a proper charge.

I don't know what your usage is and so far you have not elaborated on that but if you are not using invertors to run toasters and stuff like that then a single 160w panel and a decent size battery should be enough for general light motorhome use.

 

[REC]

Do you know what AH (Amp hour) the current battery is? If you are selling next year its pointless spending a lot of money on a Lithium set up and if you get it professionally done it will be a chunk of money. I would be looking to see what is the largest battery I can fit in the available space and just swapping it out for that. I believe the lead carbon Gel Batteries are the next best thing to Lithium and "I think" they are just a drop in.

If your current battery is say a 90ah or a 110ah can you fit a 160ah lead carbon battery in? Alpha Batteries (who we have a discount code with I think) do several. You would need to see what will fit though.

https://www.alpha-batteries.co.uk/leisure-batteries/?filter_ab_construction=lead-carbon-gel

The other thing that @merl on here taught me is that cable sizes are important. In particular I think from the solar controller to the battery. Might be useful for you to start posting some photos of all that and your set up so the experts can advise. If you dont use thick enough cables you don't get a proper charge.

I don't know what your usage is and so far you have not elaborated on that but if you are not using invertors to run toasters and stuff like that then a single 160w panel and a decent size battery should be enough for general light motorhome use.

I think the battery is 90ah, I know the converter put in heavy duty cabling for the solar panel and controller. We don't run toasters etc, when we had ehu we used about €3@.50c per kWh and that was with the fridge on full blast, and everything charging! We find the battery is not great if the fridge is on which is a compressor fridge. But we rarely use that anyway. I have searched many battery suppliers last night, inc Alpha and Tanya, Bimble but the largest we could fit is a 90ah BUT didn't know we could put one on its side . Space is 320mm long 203mm high and 170mm deep. Next job search for one to put in sideways!
Thanks for everyone's input.

 

[barryd]

I think the battery is 90ah, I know the converter put in heavy duty cabling for the solar panel and controller. We don't run toasters etc, when we had ehu we used about €3@.50c per kWh and that was with the fridge on full blast, and everything charging! We find the battery is not great if the fridge is on which is a compressor fridge. But we rarely use that anyway. I have searched many battery suppliers last night, inc Alpha and Tanya, Bimble but the largest we could fit is a 90ah BUT didn't know we could put one on its side . Space is 320mm long 203mm high and 170mm deep. Next job search for one to put in sideways!
Thanks for everyone's input.

There lies the problem then I think. 90ah is not much with only half of it being usable. I suspect the solar will charge it pretty quickly but its a bit like in my case last summer (although there were other issues with my set up) its holding that charge on cloudy days and I had a 120ah (now got two). The compressor fridge will be a killer as well although you say you dont use it much.

I think the only thing you can do is what you say, find the biggest battery possible that will fit. Looking at that link I provided from Alpha I don't think any of them will fit even on their sides.