Quick help needed on which new leisure battery to buy

[nick_the_fish]

Right, just got back from 6 weeks in Scotland and I have 1 week before I have to put the truck into a container and ship her down to Africa for a 6 month trip around Southern Africa. Unfortunately the 7 year old Varta Leisure battery has well and truly died so I need to get a new leisure battery, and I just don't have time to fully research it, so hoping someone in the know can give me some quick advise (I had a look through old threads on here and it only left me more confused!)

For background, I have a National Luna split charge system and an alternator. I don't have any of these DC-DC things which I still don't really understand, nor do I have solar or anything - just the alternator.

My question is - Can I use GEL technology with a standard alternator, or so I need a more sophisticated charging system to get it and keep it charged? I'm interested in GEL because of the greater discharge rates.

Any advise would be very much appreciated.

Thanks

N

 

[Towpack]

In theory, no, as gel batteries really require "stage charging" and reach full charge at a slightly lower voltage than the standard wet type but as long as your alternator/ voltage regulator isn't putting out more than 14.6v you should be OK. 7 years isn't that bad IMO so why not go with another Varta?

 

[Chris]

I'd echo that too. I have tried gel batteries alongside std wet cells on the same system and it killed them. Just go with a std battery but try to match it if you can to being fairly close to the main vehicle batteries. Don't fit some hoofing great big thing that won't get a full charge on a short trip. Having some form of monitoring is probably more important just so that you can see what's going on.

 

[karl2000]

AGM's dont seem to fully charge off a standard alternator voltage either

 

[Chris]

It's actually the pitfall of charging any more than one battery from an alternator in truth. It's why the double battery set up on both the Collie and the 80 suffer. The alternator sees one big battery and treats them as such when we know that are not one battery at all. What would be handy would be a dual output alternator. Never heard of one. Be tidy though.

 

[nick_the_fish]

Thanks Guys. My initial plan was to replace the Varta as was, but on this trip we are likely to stay in the same place for longer periods and I don't want to keep discharging the battery down past 50% and damaging it, so was looking for a battery that can more safely be discharged to lower states. Varta themselves in their sales literature state that their leisure batteries are best suited to occasional use, or for when you are mostly using shore power, which we are not. They reckon they can safely have 200 cycles down to 50% but it still fundamentally seems like the wrong battery for our requirements on this trip

The other thought was AGM, or even lithium, but not sure about the charging requirements of these either.

Would it help to install a DC-DC battery charger to boost the voltage into the leisure battery making GEL or AGM more suitable? @Chris in your system that you refer to, did you have a DC-DC charger or was that without? I really don't want to kill the battery in the middle of nowhere so I'd rather air on the side of caution.

Thanks

 

[karl2000]

I'm not an expert but I think DC-DC is the way forward if you have anything other than lead acid!

 

[Chris]

I had std wet and an AGM connected through a simple split charge. 6 months the AGM was showing clear signs of struggling. For me, in the simplest of terms, unless you have a bank of identical batteries (not really car related) then you need a separate charging option for every different battery. The alternator supplies all of the power of course but to a dedicated charger and then onto the battery. I have 3 DC2DC set ups. One in the 80, one in the Hilux and one in the Metalian trailer and they all do the business. As well as accepting the solar input to the best advantage straight into the aux battery. I also have a VSR split charge between cranking and vehicle 'systems' battery in the 80 as I went to 12v start. But they are paired left and right handed batteries, the same.

DC2DC is not just for AGMs, it's for any batteries that charge and discharge differently. The basics here are if you discharge them differently then you need to charge them differently. What you do NOT need is some hoofing great big unit whacking out 100 amps. It just needs to be a separate stream. My ABR Sidewinder is only 20 amps max and it never hits that.

 

[nick_the_fish]

Okie Dokie, Spent the morning learning about DC-DC chargers etc.

Opted for a Redarc BCDC1225d which should sit neatly in place of the National Luna system I currently have. I'll then get a Victron Super Cycle 100AH or 125AH AGM battery to go with it, and a portable solar input so that if we are sat for days at a time we can top up the battery from the strong African sun.

Thanks for the help chaps. Very much appreciated as always

N

 

[Chris]

Very nice! You'll find that with a good battery keeping it topped up with solar is very efficient. Even in the UK a small set up will keep you near 100% most of the time and it's that top end charge that keeps the battery happy. We had decent enough weather in Scotland week before last and the solar kept the fridge going all day. We'd come back to the car to find everything chilled and the batteries at 100%.

 

[nick_the_fish]

You were in Scotland week before last?? So was I!! I wish I'd know I'd have tried to meet up. Hope you had a good trip. We spent 6 weeks up there, 3 of them in the Outer Hebrides - It was pretty much windy and wet the whole time, and the midges near Ullapool........

 

[Chris]

We did NC 500 with the bikes towed on a tailer with the Hilux. Oban, Fort William then on up to Tongue. With visits to Skye and John 'O. Despite the NC500 being 500 miles we actually did nearly 1000 on the bikes. Yes the midges were little blighters.

 

[Bmonck]

Hi Nick
i did a ton of research and came up with the same conclusion as you : Redarc 1225, agm 110Ah plus fixed solar
& as you will know now the 1225 will prioritise taking as much charge as possible from the solar before it bothers the alternator.
As an aside good though Lithium are I didn’t think they were worth the price - yet. Prices continue to come down so maybe when I replace the AGM.

 

[nick_the_fish]

Sounds Great! We may well have been in the same area at the same time, but you know my truck so I'm sure you'd have hooted if you'd seen us. Maybe next time. Glad you have a good trip.

 

[nick_the_fish]

This is reassuring to hear. I normally like to mull over decisions like this for weeks before making a conclusion so this one felt rather rushed, but I am confident its the right one. Which solar panels are you going for? We are not using fixed in this set-up, but I'll prob try and find a portable one that can be plugged in when we stop.

Any further thoughts on your Pan-America trip?

 

[Batts88]

Lithium is definitely worth the extra as a future upgrade. I've only had mine a short time but going from 2 x 105ah agm's which lasted just over 5yrs, weighed together 58kg to one 170ah Renogy lithium at 21kg with decent increase in usable power.

 

[StarCruiser]

Think I’m a bit late to the party here but it’s worth bearing in mind the Intervolt DCDC chargers. The gen 2 ones can cope with standard wet, AGM, Gel and lithium (with a suitable BMS) with solar MPPT input and a display in the cab.
All at 25A all day long in Australia heat under the bonnet and waterproof in a footprint the size of a CD case.
I have stock of these if anyone is interested. There’s a thread on here somewhere about them.

 

[Dave_S]

Nick - in my van we have a 150w permanent solar panel feeding the AGM leisure battery, and a split charge feeding the main vehicle wet cell battery and the AGM. AGM is coping no issue and will run indefinitely during Spring to Autumn in the UK powering our fridge etc if parked up. I know you weren't looking at permanent solar, but if you have the real estate on the roof I would recommend it, as you really don't have to think about it... it just does its thing.

 

[nick_the_fish]

Lithium is definitely worth the extra as a future upgrade. I've only had mine a short time but going from 2 x 105ah agm's which lasted just over 5yrs, weighed together 58kg to one 170ah Renogy lithium at 21kg with decent increase in usable power.

Thanks @Batts88 , I am sure I will be moving to Lithium at some point in the future, but its still a little pricy for me. Also I understand that you can't run them off a standard alternator? Although I might be wrong about that.

Think I’m a bit late to the party here but it’s worth bearing in mind the Intervolt DCDC chargers. The gen 2 ones can cope with standard wet, AGM, Gel and lithium (with a suitable BMS) with solar MPPT input and a display in the cab.
All at 25A all day long in Australia heat under the bonnet and waterproof in a footprint the size of a CD case.
I have stock of these if anyone is interested. There’s a thread on here somewhere about them.

@StarCruiser Rich your thread on the Intervolt was the first thing I read when I started looking at these last week. Annoyingly I didn't realise you were stocking them, and I couldn't find them easily in the UK otherwise I would have considered them very seriously.

Nick - in my van we have a 150w permanent solar panel feeding the AGM leisure battery, and a split charge feeding the main vehicle wet cell battery and the AGM. AGM is coping no issue and will run indefinitely during Spring to Autumn in the UK powering our fridge etc if parked up. I know you weren't looking at permanent solar, but if you have the real estate on the roof I would recommend it, as you really don't have to think about it... it just does its thing.

Yep @Dave_S I decided that my surfboard is my important than solar panels on the limited roof space we have. A bit of a no brainer really.......