Dual Battery Management

[StuartL]

Hi Guys,
I am getting down to the wire (ha ha) on my winch installation on the 109". I am picking up the new Pangolin "smiley" winch bumper on Thursday and need a quick practical solution to add a battery and manage it.

I need a dual battery tie-down to fix under the drivers seat, I just want to go and get it at a local store...any ideas? :idea:

I also need a battery management system for the dual batteries to charge them both but to insure if Adam is on his Playstation all night I can still start the truck in the morning. Who should I approach locally? :idea:

Thanks to all that offer suggestions :lol:

[ANDYD]

Hi Stuart,
The easiest way to connect dual batteries is to install a manual switch with a 1,2.both, off positions.
this is common on boats like shown in this link;

http://continuouswave.com/whaler/refere ... ttery.html

The down side to this simplisity is you have to manually switch-the-switch to select which battery is getting the charge or supplying the power (or both can be selected).

Alternatly a automatic split charging box can be purchased, this senses which battery needs the charge & switches automatically to the one in need.

Any of these switches, auto-split charging devices or battery trays can be bought from Canadain tyre, Lordco, marine suppliers etc....

Good luck,
Andy

[96whitedisco]

A marine dual battery switch would work well as they come in differant amp sizes so you can run both batterys when on the road and charge them. then switch to the aux battery for your winch or any other rv purpose like rv liting your camp ground up.

cheers
Andrew

[DaveB]

Easier still is an always-on solenoid, which can be purchased at canadian tire for about $15 in the RV section. Then you wire it so that the ignition and starter runs off of one battery and most of the accessories such as winch and your 12V accessory plugs run off the second battery. Thus you will always retain your main battery for starting, with the connection between the two broken when the key is off. Then as soon as you start your truck, the solenoid is activated and joins the two positive leads and charges both. Super easy to set up, totally automatic with no switches to remember to switch.

Dave

[JD]

Stuart,

If you go for the "simple" 1,2, All marine battery switch be very careful to get a "make before break" type of switch. Most normal marine 1,2 switches are "break before make" thus disconnect Line Out from battery as they change position. This will remove load from your alternator and cause it to destroy its rectifying diodes.

If you go with a "split" charging system using an RV style diode module, without lowering the "sensing" voltage with another diode, your batteries will charge about 1.5vdc low.

One solution is straight parrallel charging with a solenoid that can either be manually activated or connects when the oil pressure switch goes on ensuring only the start battery is used during start. I have this method in place for my start and house batteries. I use a manually switched solenoid and use a volt meter set to %of charge read by a small volt range in the 14 to 18Vdc area. This works for me because my house batteries and my starting battery are different - deep cycle for the house and a normal automobile starter battery.

Overcharging of your second battery bank is quite possible causing boil off so you need to find the solution that works best for your batteries and the charging rate of your alternator.

Hope this helps.

Rgds
JD

[kRiS]

you could have a look at this from BC4x4

http://bb.bc4x4.com/showthread.php?s=&threadid=90160

[DaveB]

What Steve has done there is exactly what I was trying to explain.

http://gallery.hot4x4.ca/albums/album253/aai.jpg

Dave

[StuartL]

Hey guys,

Thank you for the suggestions. I like simple....

I bought a Marine Switch but I amperage just isn't high enough for the batteries...

[Greg S]

The switch amperage isn't determined by the batteries. It is determined by what you are going to be drawing from the batteries. What is the draw on the winch? Is it within the specs for the switch?

[JD]

Stuart,

Did you ensure it was a "make before break" type?

JD

[PaavScan]

Justed looked at the battery management system at Lordo.

Has any one installed a split charging in a Disco?

I plan to run a fridge @ etc.

The blue top Otima will be on sale at Costco for $35. off April 9 to 15 list 179.99 group D34 870 amp.

Stuart

[JD]

I've installed lots of split charging on boats. Took my split charging and changed it to direct parrallel charging using a solenoid. I feel that the batteries get a better dual charge this way. Split charging only senses one battery for the alternator to charge to. So one battery could be either over or under charged depending on condition of battery. Solenoid hooked up to oil pressure switch so starting doesn't draw on the deep cycle battery.

On a split charging system it is also important to put a diode accross the sensing wire to lower its voltage by the same loss as the charging diodes. Then the alternator charges truer .

Not seen a Lordco system, but they must all be similar.

Cheers
JD

[red90]

Justed looked at the battery management system at Lordo.

Has any one installed a split charging in a Disco?

I plan to run a fridge @ etc.

The blue top Otima will be on sale at Costco for $35. off April 9 to 15 list 179.99 group D34 870 amp.

Stuart

You can get the (rebadged) Exide Oribital Deep Cycle/Starting Marine battery at Crappy Tire for $170 anytime. It is basically equivalent to the Optima Blue and possibly better.