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excossack



Member Since: 22 Feb 2012
Location: North West
Posts: 5725

United Kingdom 1999 Defender 110 Td5 SW Caledonian Blue
What battery for a split charge?
Split charge system is a relay activated by a ignition live feed (radio)
The battery is currently a standard car battery of around 100ah. This needs replacing.

So thinking of two batteries, but standard car or starter/leisure battery?

Most items that run off the 2nd battery are; rally radios x3, quad band ham transceiver , phone chargers, work lights and sometimes a cool box.

Planning on linking together to have the ability to have one 'big battery' and also the option to act as a jump start should I get a flat battery via an on / off switch to link main battery and 2 aux ones. 1999 Defender TD5 110

Regards
John M0VAZ
Econet Station 48 no clock
Post #575307 3rd Nov 2016 9:32pm
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macfrank



Member Since: 05 Nov 2015
Location: somewhere in the north
Posts: 983

Germany 2015 Defender 110 Puma 2.2 SW Keswick Green
I chose one that's similar to the original (which is still in place as the starter battery). Same size, about the same capacity (100Ah), but gel, deep cycle and also able to start the car

https://www.autobatterienbilliger.de/ECTIV...-GEL-100Ah
(sorry couldn't find a uk web site)
Post #575342 3rd Nov 2016 11:01pm
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dantastic



Member Since: 04 May 2010
Location: London
Posts: 367

United Kingdom 
A regular battery is great for starting the car. It is good at delivering a very high charge all in one go.
Look at getting a leisure battery instead. They are better at being discharged down to much lower levels than a starter battery can ever cope with. You can still start the car with a leisure battery in an emergency situation.
Post #575371 4th Nov 2016 7:14am
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Cupboard



Member Since: 21 Mar 2014
Location: Suffolk
Posts: 2971

United Kingdom 2011 Defender 110 Puma 2.4 HT Corris Grey
OK there's a common myth about "leisure batteries" being different from "starter batteries". For the size of batteries we're talking about, they're the same. There is no difference.

When you're looking at proper deep cycle traction batteries then yes, there is a difference but they're not remotely in the realms of what you'd consider putting in a Defender.

Some background reading here: http://www.aandncaravanservices.co.uk/battery-technology.php
And there's a thread that's recently resurfaced from 2012 where someone has put a really long and informative post on the subject. (quoted below) http://www.defender2.net/forum/post575217.html

I've fitted one of these as my second battery: https://www.tayna.co.uk/Type-110-Varta-Sil...P7709.html
It's a bit shorter than the standard battery (which is a 019) and loses about 5Ah of capacity but has the same (or similar) CCA. I bought a slightly smaller one because I thought I would have trouble fitting another 019 but actually having now done it I think it would be possible - and that's with a winch isolator, spit charge relay and I think my jump leads in the box too.

Most batteries are rated for something like 400 cycles to a 50% dept of discharge - that means you can regularly take half the battery's nominal capacity out of it and still have a sensible lifetime so you need to do a power budget and work out if that's sensible. There are batteries rated to a lower DoD, the Odysseys are rated down to something like 30% which means that for a lower headline capacity they actually have the same usable energy storage. They are a low more expensive though.

Split charging: I would be reluctant to do it ignition switched and would prefer to have some sort of voltage sensitive relay. The reason being if you've drained your auxiliary battery then when you try and start you'll be drawing the starter battery down with the aux one. It's probably not going to be a ginormous current, somewhere between 50 and 100A, but it's not going to help the starting process. I use a Victron Cyrix CT 230A which allows me to manually combine the batteries for winching or jump starting myself and I'm pretty happy with it. Other ones are also out there - but I did a lot of research before buying that one.

tatra805 wrote:
Ok, well, cant keep out of it anymore Whistle

Some battery ranting

Most terms are used mixed and regardless of real construction parameters.
AGM, GEL, Deep Cycle, capacity, etc etc

AGM - GEL –WET
Status of the electrolyte

AGM: inside a glassfibre matting,
GEL: Gel status, not liquid
WET: just the liquid electrolyte


Wet has the disadvantage it will leak when upside down as the electrolyte is a pure liquid. The “plates” are nothing more than lead plates. In the mean time no leaking till 90° for short time solved by matrixes in the battery caps and the plates evolved to matrixed plates for bigger contact surface etc etc

Gel solved the leaking issues, still venting is necessary but the gell is not passing through the sintered filter openings. (eg optima) The disadvantage of gel is that it does not transfer charges as easily,(the gelling part of the formulation is not conducting) hence the need for spiral designs, which just means there is a bigger contact surface between the plates and the electrolyte. This resulted also in a better CCA, as this is directly related.(bigger surface can conduct more energy at same time) But as less active electrolyte per cubic the capacity of the same external volume of the battery is lower. (simply put there is more lead vs electrolyte in it, less electrolyte = less capacity + less electrolyte as the gelling agents are also taking part of the place)

AGM is the “new hot topic” but nothing more than an in-between. Instead of making gell you absorb the normal liquid in a matting. Less chance on leaking + clever venting matrix designs makes them quasi as safe as a gel type. Liquid instead of gel makes for better contact and charge exchange so capacity is up (a bit) and in case combined with a spiral design of the lead plates an even higher CCA than GEL.


(exclude variants)
(note that leaking is also related to gassing when charging, sealed batteries need a better controlled and at lower amp charging process as gasses cannot escape and would make the batteries explode under pressure build up. Also Optima has venting holes, AGM batteries also to allow for a faster charging spec (but still slower than an open battery))

Due to the bigger contact areas (and with the right charging systems) you can “deep cycle” the AGM and Gel better than a simple plate design.
Sulfurisation of the plates is also less an issue as you have more plate surface available. (sulfur on plates= no more conducting, 5% of a classic plate or 5% of a 10 times bigger spiral surface makes the plate is quicker to not charging anymore while the spiral will. It is the charging process that kind of auto-cleans the plates but you need a min current for that which the plates are not able to conduct anymore in that case)

But still, even on optima and others, this is a far cry from real traction batteries which are real deep cycle.

Deep cycling means discharging till 40% of charge. ALL batteries can do this but not all can recover from it. A real traction battery can take up to 3000 deep cycles, a GEL/AGM/ WET deep cycle or leisure battery up to 300, a normal classic lead acid 0 if lucky you’ll survive a couple.

So,if you want top level deep cycling, as you know you will run your batteries empty each and every time and you will only have the chance to charge them x time after that, go for sealed traction batteries. They will cost you 6 times more but you can expect 20 years from them in those conditions. (well, yes 10 years if you flatten them completely 300 times per year… and that is manufacturer guarantee)
You’ll need to build up your banks with individual 6 or 12V cells till you reach your desired capacity.


Now why all this explanation?

There is no reason to prefer GEL or AGM IF you do not have a leaking/positioning issue.

With a wet deep cycle battery you will get:
- normal CCA
- almost double capacity Ah (90 vs 55)
- 1/3 rd of cost
- identical deep cycle resistance

So people into competition that must run under any angle I completely support in their choice of AGM/GEL.

But for campers, overlanding or home warriors I do see a disadvantage in them and although I consider them though and good batteries a waste of money in those situations.

A 50Ah Gel battery will not run your fridge and webasto for 12 hours, even if after recovery the battery has enough juice to restart the systems and run for another hour the build in voltage detectors of your fridge and webasto will switch off after about 6-8 hours.

(not taking in consideration extreme temps/other users which makes things only worse)

With a wet cell you will run them 10-12 hours as you simply have 45% more Ah available.

It was a positive surprise to me to see that Landrover itself selected a deepcycle battery as oem and not a classic car starter battery. (see my previous post)


Another point which I consider important for me.
When putting 2 OEM (or varta’s) of equal type parallel as normal and AUX battery you don’t need a special charging system. When putting a wet and eg an optima in parallel you will never charge them correctly and this will lead to premature failure of the weakest of the two.
So you’ll need to put in a split charging device. (that is not a 100£ fancy battery separator as the national-luna etc, it is a separate charging system as found in marine applications or eg the CTEK one)
Or you’ll have to put in 2 optimas at once. Project cost immediately double and you’ll only have 2x50Ah instead of 2x90Ah. (both CCA enough for starting but the optimas will give in earlier, I guarantee, it's math)

I like equipment and the more the better but not if it is unnecessary.

To me all these batteries have their place and application. But I had too many friends asking me to help them out with constant empty optima’s blaming everything but not understanding that Ah was the only thing they needed in the first place and not the latest hype.

To make it a bit constructive and to answer the original question

1. Don’t deep cycle your batteries, it is an option only for extreme/emergency situations with anything but real traction batteries anyway.
2. Calculate you capacity needed, without that you’ll run out of juice with any type of battery
3. Consider your existing equipment, doesn’t make sense to make things worse.
4. Tune your equipment, right battery for right charging system etc
5. Count your coins as everything is possible and each approach has its pricetag

Respect above 5 and you’ll be a happy camper. Take a shortcut and you’ll put a weak link in the your system.

Friendly 2cents only Very Happy

PS: I have hands on experience with all types mentioned above except AGM’s. (But also studied their specs) in all different types of applications (stationary and mobile)
Post #575378 4th Nov 2016 7:46am
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excossack



Member Since: 22 Feb 2012
Location: North West
Posts: 5725

United Kingdom 1999 Defender 110 Td5 SW Caledonian Blue
Thanks for the info. So really then, a leisure battery will still do as a jump start source, can be drained a bit more than a car battery.

I have thought about a VSR to trip the relay to enable the split charge, probably something I will look at later on.

A battery such as > http://www.ebay.co.uk/itm/12V-130AH-130-AH...SwzaJX9Rhf 1999 Defender TD5 110

Regards
John M0VAZ
Econet Station 48 no clock
Post #576126 7th Nov 2016 9:41pm
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Cupboard



Member Since: 21 Mar 2014
Location: Suffolk
Posts: 2971

United Kingdom 2011 Defender 110 Puma 2.4 HT Corris Grey
Yes you can use a VSR to trip a bigger relay that would work fine.
Or just buy a VSR that can cope, like the Cyrix CT 230 which does almost everything I want in a battery combiner: http://www.12voltplanet.co.uk/12v-24v-230a...biner.html

A leisure battery can be used as a jump start source, yes. They don't deep cycle any better than a starter battery though - the reason being is that the difference between the two is the sticker on them. If you look at the one you've linked to it claims to be a dual purpose battery.

On the subject of the battery you've linked to, I have to say I'm a bit suspicious. The dimensions suggest that it's a 019 battery, same as the standard starter battery in the Defender. Except 019 batteries are at best 100Ah not 130Ah. It's possible that Probat have managed to come up with something better than Bosch, Varta et al, however I think it's more likely to be marketing. If you look at a 130Ah battery from a manufacturer that you've heard of and you'll find they're a lot bigger than that.
Post #576155 7th Nov 2016 11:12pm
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excossack



Member Since: 22 Feb 2012
Location: North West
Posts: 5725

United Kingdom 1999 Defender 110 Td5 SW Caledonian Blue
Thanks for the hint, I hadn't noticed the size of the battery sounded too small for the Ah.
I wasn't planning on buying another relay for the setup, but I was planning on using an old winch isolator already mounted to the seat box to use as a manual link if I needed to link all batteries together for boosting the starting capacity. 1999 Defender TD5 110

Regards
John M0VAZ
Econet Station 48 no clock
Post #576313 8th Nov 2016 6:03pm
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excossack



Member Since: 22 Feb 2012
Location: North West
Posts: 5725

United Kingdom 1999 Defender 110 Td5 SW Caledonian Blue
Old)(ish) thread revival.... After some hunting for a battery of the right height I found this

http://www.batterymegastore.co.uk/batterie...xv110.html

Appears to do what I want?

Its difficult to work out the re-badged car batteries Vs Leisure batteries. According to the seller, this will give me what I am after (powering radios, lights and occasional use as a starter battery) 1999 Defender TD5 110

Regards
John M0VAZ
Econet Station 48 no clock
Post #605551 28th Feb 2017 3:32pm
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macfrank



Member Since: 05 Nov 2015
Location: somewhere in the north
Posts: 983

Germany 2015 Defender 110 Puma 2.2 SW Keswick Green
Looks correct, and cheap. Measures the same as the orginal one. AND - it has 110 Ah - 110 - I mean, how can this be wrong... Very Happy

I have an Ective 100Ah Gel as second battery along with the original one. Same dimensions.
Post #605563 28th Feb 2017 4:44pm
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Jim G



Member Since: 21 Jul 2014
Location: Ormskirk
Posts: 92

United Kingdom 1984 Defender 90 300 Tdi HT Stornoway Grey
Do not use a 'leisure ' battery to start a vehicle, they are different from a standard car battery, they have more or thinner plates, and are designed for slow discharge to a lower level, if you start a car with one then you will buckle the plates and destroy the battery .
There are special ' dual' usage batteries which can be used to start a car in an emergency and are still 'leisure ' type.
Post #606038 2nd Mar 2017 12:19pm
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bpman



Member Since: 21 May 2008
Location: Oslo
Posts: 8069

2008 Defender 110 Puma 2.4 SVX Station Wagon Santorini Black
Duracell make vehicle batteries now .. I have one in my M3, more powerful than the OEM, and gell/glass cells.

Bit cheaper than the Odyssey and have 3 or 5 year guarantees ... and they are black and gold Thumbs Up
Post #606042 2nd Mar 2017 12:36pm
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excossack



Member Since: 22 Feb 2012
Location: North West
Posts: 5725

United Kingdom 1999 Defender 110 Td5 SW Caledonian Blue
Thanks for the advice, the battery I linked to is a dual purpose one which by the looks of it will cover off what I want to do. 1999 Defender TD5 110

Regards
John M0VAZ
Econet Station 48 no clock
Post #606048 2nd Mar 2017 12:55pm
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Cupboard



Member Since: 21 Mar 2014
Location: Suffolk
Posts: 2971

United Kingdom 2011 Defender 110 Puma 2.4 HT Corris Grey
Jim G wrote:
Do not use a 'leisure ' battery to start a vehicle, they are different from a standard car battery, they have more or thinner plates, and are designed for slow discharge to a lower level, if you start a car with one then you will buckle the plates and destroy the battery .
There are special ' dual' usage batteries which can be used to start a car in an emergency and are still 'leisure ' type.


Did you read any of the previous thread? Your comment suggests you did not. Please go and read the rest of the thread, because in a nutshell you're wrong. You do get deep discharge traction batteries which are genuinely built with thicker plates however not for this sort of application. Electric forklift, yes. Leisure battery, no.
Post #606224 2nd Mar 2017 9:25pm
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