Duel battery set up

[elty001]

Been thinking for a while now about installing a second battery.
Thinking of going for 120 amp leisure battery for running all my ancillaries off but could do with a few pointers from folks with any knowledge of fitting split charge systems.:nenau

 

[don simon]

First things first. Where are you looking to locate this second battery?

 

[panelbeater]

i have a 180a battery in back of my terrano charged up when engine running via cigar lighter,been working for years.
connected to that battery is a 1500w inverter so when my solar panels do not put out enough charge on van i then connect ehu from inverter to van this then charges up van battery via built in charger.
i never go ehu unless there is no option on where i am staying.
its tried and tested over years and works for me.
i also have my 180w led light bar connected to rear battery switched and fused, as well.

 

[zippy656]

Hope its in a proper battery box, ventilated to out side...

And fixed down.

 

[Lazy-Ferret]

If you are putting the battery on the Near side under the bonnet, and you have aircon, I don't think you will be able to get a 120ah in there as the pipes run past, limiting you to the 80ah(ish) size...

I put a bit of info in my car thread.

http://www.nissan4x4ownersclub.com/forum/showpost.php?p=321024&postcount=123

 

[zippy656]

I've my heat exchanger there

 

[don simon]

If you are putting the battery on the Near side under the bonnet, and you have aircon, I don't think you will be able to get a 120ah in there as the pipes run past, limiting you to the 80ah(ish) size...

I put a bit of info in my car thread.

http://www.nissan4x4ownersclub.com/forum/showpost.php?p=321024&postcount=123

That's smack where my washer bottle is (ignore the maf arrow).
18618914630_c8a5a1a44f_z by Simon Carter, on Flickr
Nuts!!
Sorry for the hijacking.

 

[elty001]

My air con is stuffed so pipework can come out to make a bit more room.
My washer bottle is under the driver's side wing so again no issues there.
I will have to re route the pipe but work for the snorkel but again not too much of an issue.
It's the electrical side of things i want a bit of info on.
Have been looking at various kits on the web but want to make sure I get one that meets the needs of what battery i fit.

 

[elty001]

This is a slightly smaller battery that I might just be able to squeeze in with the air con pipes removed.
http://vi.raptor.ebaydesc.com/ws/eBayISAPI.dll?ViewItemDescV4&item=321067938559&category=108845&pm=1&ds=0&t=1487887065444

 

[rustic]

This is a slightly smaller battery that I might just be able to squeeze in with the air con pipes removed.

I don't think you've compromised on that one, ticks most if not all of your boxes.
Just make sure it is fixed down, and bits off the engine don't rub the side. Also make sure all wiring is in conduit (or hose) to protect the cables. If it is not to be used for starting, fit an appropriate mega fuse near the battery +ve terminal. Size to suit your smallest wiring.
Cover the terminals, as the battery top makes a nice shelf for spanners lol.

I informed my insurance company, they at first said no, after a discussion and I advised them that I was an electronic engineer and that it would be fitted correctly they said ok. I think they must have had a few claims from fires starting in the area of a second battery, when poorly installed.

This is my installation, the battery is the previous mav battery... keeps it simple, I have a 1970's type starter solenoid (big relay really) that I can switch in to give a boost to main battery, it is charged when the engine is running, through a 45 amp relay, with fuse, the relay is energised from the radio feed, ie it drops out when engine starting, otherwise the 45 amp relay will be passing some starting current.
Hope it helps.
Uncle Rustic.

 

[elty001]

Thanks Rustic!!!!! that helps me out a lot:thumb2
this is the split charge kit i was looking at,we use durite products at work so could well get it a little cheaper :thumb2
http://www.ebay.co.uk/itm/3mtr-Split-Charge-Kit-12v-140amp-Durite-Voltage-Sense-Relay-110amp-cable-T4-T5/261599613436?_trksid=p2047675.c100009.m1982&_trkparms=aid%3D888007%26algo%3DDISC.MBE%26ao%3D1%26asc%3D41415%26meid%3D642f525c211a4a809720097dc6b45f9d%26pid%3D100009%26rk%3D1%26rkt%3D1%26sd%3D261382972047

Iv'e got an unlimited modifications insurance policy so as long as i declare it there shouldn't be any problems.

 

[Lazy-Ferret]

Thanks Rustic!!!!! that helps me out a lot:thumb2
this is the split charge kit i was looking at,we use durite products at work so could well get it a little cheaper :thumb2
http://www.ebay.co.uk/itm/3mtr-Split-Charge-Kit-12v-140amp-Durite-Voltage-Sense-Relay-110amp-cable-T4-T5/261599613436?_trksid=p2047675.c100009.m1982&_trkparms=aid%3D888007%26algo%3DDISC.MBE%26ao%3D1%26asc%3D41415%26meid%3D642f525c211a4a809720097dc6b45f9d%26pid%3D100009%26rk%3D1%26rkt%3D1%26sd%3D261382972047

Iv'e got an unlimited modifications insurance policy so as long as i declare it there shouldn't be any problems.

That looks almost identical to what I installed on my car, only I got the bits separately. The relay is good and simple to install, but it does have a few issues. It uses the voltage of the first battery to decide when to switch in and start charging the second battery, which at first seems a good idea, but what I do find is, often, if you stop the car after a good run, then restart it, e.g. after filling with fuel, the voltage on the first battery has not dropped enough for the relay to drop out, so you end up starting the car with both batteries in circuit, which can then cause the fuses to blow.

On Suz's car, I used a 200amp relay switched from the alternator, so there is no way the battery can be in circuit, unless the engine is actually running, and will be doing the same on my car once it gets a bit warmer out there and I fancy working on the car.

this is the relay I am using...
http://www.ebay.co.uk/sch/i.html?_odkw=200+amp+12v+relay&_sop=15&_blrs=spell_check&_osacat=0&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.X200amp+12v+relay.TRS0&_nkw=200amp+12v+relay&_sacat=0

This relay is more like the Solenoid Rustic used, only the solenoid is capable of switching and conducting even larger currents. The only thing with the Solenoid, which Rustic seems to disproved, I was taught solenoids were only supposed to be held in for short durations, as they draw quite a large current compared to relays, and get pretty hot over time, causing their coil to burn out.

 

[rustic]

... The only thing with the Solenoid, which Rustic seems to disproved, I was taught solenoids were only supposed to be held in for short durations, as they draw quite a large current compared to relays, and get pretty hot over time, causing their coil to burn out.

You are 100% correct. It is a solenoid, it is only on a momentary push switch, that will only get used when vehicle cranking only, maybe 10-15 seconds max.

It is a "get out of jail free card". The Mav is garaged 24/7 so starts on the button every time, but I found just once... that if left outside overnight in the cold, with a failing battery, that I didn't suspect, that it wouldn't start. Not really used the second battery for it's real purpose since, but as it's in circuit when running, the lights seem to like it.... off road of course...
Close to 400 watts of bright white lights up front. lol :naughty
All controlled to be on, on full beam lol... with subtle switching.

It would also serve as a short term boat back up too.:thumb2

 

[Lazy-Ferret]

You are 100% correct. It is a solenoid, it is only on a momentary push switch, that will only get used when vehicle cranking only, maybe 10-15 seconds max.

It is a "get out of jail free card". The Mav is garaged 24/7 so starts on the button every time, but I found just once... that if left outside overnight in the cold, with a failing battery, that I didn't suspect, that it wouldn't start. Not really used the second battery for it's real purpose since, but as it's in circuit when running, the lights seem to like it.... off road of course...
Close to 400 watts of bright white lights up front. lol :naughty
All controlled to be on, on full beam lol... with subtle switching.

It would also serve as a short term boat back up too.:thumb2

That makes more sense... So I take it that's not the relay you are using to charge the battery when you are driving then,and you are using another relay somewhere.

 

[rustic]

That makes more sense... So I take it that's not the relay you are using to charge the battery when you are driving then,and you are using another relay somewhere.

Yes a typical accessory type relay, 40 or 45 amp contacts, sort used on spot lights etc.:thumb2

 

[Lazy-Ferret]

Yes a typical accessory type relay, 40 or 45 amp contacts, sort used on spot lights etc.:thumb2

Sorry, you did say that in your post... I miss read and thought you were using that relay to pull the solenoid in... My Bad.:bow

 

[rustic]

Sorry, you did say that in your post... I miss read and thought you were using that relay to pull the solenoid in... My Bad.:bow

No probs, I don't always make things that clear, what goes around my head isn't what I always write down lol...

I put it down to the medication lol...Most stuff I take says "May make you drowsy" I was surprised to see that on a packet of sleeping tablets once lol...:doh

I would say half the medication I take is for side effects of the other half...

Uncle Rustic

 

[elty001]

Cheers for all the info guys:thumb2
Got a few files saved with different installs to have a look at over the weekend.

 

[bbbmmm55]

So im looking to install a second battery. Mainly to assist starting if needed. Im posting in this thread as it all seems relevant to my situation.

I would like to have something like Rustics set up as i dont have any additional bits to run from the second battery at the moment.

Rustic mentions he has an old type solenoid and momentary switch, so ive found this on ebay.

 

[bbbmmm55]

Now in another post by Kitchenman I ve stolen a wirng diagram. If I were to add Rustics on top should I have something that looks like this?