Placement of 2nd Battery

Bullbars, roof racks, suspensions and other accessories relating to vehicle performance
User avatar
Saltman
Moderator
Posts: 281
Joined: 04 Apr 2009 16:03
Full Name: Herbie Hellstrom
Nickname: Saltman
Home Town: Durbanville, Western Cape
Current 4x4: Land Rover Discovery Series 3 TDV6 Auto
Land Rover Discovery Series 1 Tdi.
Land Rover Discovery Series II Td5
Home Language: Afrikaans / English / German
Location: Durbanville, Western Cape

Re: Placement of 2nd Battery

Post by Saltman »

Gentlemen

Having learnt some hard won experience, just be aware of the following:

There are a couple of additional concerns when placing the 2nd battery in the engine bay of a 4.8 with ABS, particularly if you place it next to the 1st one:
1) mass is all on the drivers side (26Kg per battery), so if you drive alone, then you are looking at 54kg + driver (75 - 100 kg), a constant load for which the coil spring on that side was not designed
2) the 2nd battery is then very close to the engine and the 4.8 gives off a fair amount of heat. Battery + heat = not a good combination = very short life
3) make sure the batteries are the same size. Unless you have a very intelligent 2nd battery charging system, the smaller battery will get fried over a period of time as the alternator sees the overall load and supplies charging current accordingly.
4) and do not place a gelcell under the bonnet, it does not do well under the heat conditions found close to the engine!

I like Wilfred's installation. Unfortunately I do not have a drawer system in the back of the Patrol.
What I have done is to make a 12 mm marine plywood board in the shape of the rear compartment floor layout. I covered the board in automotive carpet and bolted it to the floor using existing Nissan bolt holes that all have nuts welded to the chassis side. (14 in total - small and large)
In this board I have added slots through which I rigged straps. These straps tie down my 50L water tank when in use. Where I do not require the water tank, the straps are used to tie down the National Luna 2nd battery set up (the grey box) and my recovery gear ammo box. In strategic places I also fitted those nuts with the upturned sharp edges that "bite" into the wood. These allow me to bolt down the fridge and the battery when I do use my water tank.

To power the grey box I installed a heavy duty welding cable to the rear of the car from the 1st battery. I have a 175A Brad Harrison connector for the trailer battery and from this I tapped off power to a marine fused distribution panel. Now I can add any equipment to the rear, just connect it to the supply.
In addition I added a red 50A Brad Harrison plug next to the marine DB and that is used solely to charge the grey box. Another grey 50A BH plug is available for equipment that draws major current (compressor etc).
The setup has worked well to date, however I would still like to make provision for solar panel charging when I camp for more than 2 days in one spot - fortunately this does not happen that often, as we prefer to move on and explore other areas!

Hope this gives some food for thought.
Herbie
Saltman:
One foot in Land Rover land and one foot in Patrol land and the sensitive bits are hanging in the salty sea in between!
User avatar
jan.dup
Senior Member
Senior Member
Posts: 209
Joined: 08 Jun 2011 11:43
Full Name: Jannie Du Plessis
Nickname: Jannie
Home Town: Hermanus
Current 4x4: Patrol 4.8 GRX
Home Language: Afrikaans
Has thanked: 29 times
Been thanked: 13 times

Re: Placement of 2nd Battery

Post by jan.dup »

Had a quick look in front of my new Playmate :biggrin: and must say on first inspection it looks a bit difficult to fit the battery in the engine compartment without fiddling to the extend of a broken warranty. Almost sure that I will have to go to the back with that - also makes sense what you say Herbie.
JG Shields
Patrolman
Patrolman
Posts: 789
Joined: 18 Aug 2009 14:52
Full Name: JG Shields
Nickname: JG
Home Town: Pretoria
Current 4x4: Toyota Land Cruiser 105 GX 4500 EFi
Home Language: Afrikaans
Location: Pretoria

Re: Placement of 2nd Battery

Post by JG Shields »

I agree with Herbie. Wilfred's setup is perfect, if the drawers system is a permanent fixture in the car. Yes, stay away from fiddling with modifications in the new Patrol's engine compartment.

After careful and long considerations, I also installed the "charging" system in the engine compartment with a portable battery pack, fed by a cable, in the luggage compartment of my Patrol. I also had the brad-harrison at the back next to the towbar which gave me the option to put the battery in the trailer if I did tow and used the jump seats. This option has many advantages:

1. No modifications to the vehicle.
2. No permanent space is taken up anywhere in the car.
3. The battery pack adapt to your load/luggage configuration and not the other way round.
4. If and when you set up a long term camp, the battery pack serves a handy purpose inside a tent, close to the fridges and available for lights. For this purpose my generator system is also adapted to charge the battery pack.
5. When the battery pack is not in use, it stays on a shelve next to my work-bench where it is regularly charged and used as 12V power source at my work station.

I bought by current vehicle with an engine compartment installed second battery as well as brad-harrison 12V outlets at the back. Therefore I suddenly find myself with a 3 battery setup in my car...but I am still looking for a proper use for all the battery capacity...ha...ha
Patrol fan!
Post Reply

Return to “18. Vehicle Accessories”

Who is online

Users browsing this forum: No registered users and 1 guest