Adding a second battery

Smokey · 17-08-11, 01:18 PM

This I don't actually have an answer for.

How easy is it to install a second car battery, for example, in the boot.

Surely it's not as simple as piggy backing the main battery via alternator?

Just thinking ahead for my pc install which should be started in a few months.

Cheers

talkingcars · 17-08-11, 01:34 PM

Install a second battery in the boot, a deep discharge lesuire battery for a caravan is best. Then install a split charger which will always insure that the main battery is charged before diverting charge to the second battery.

http://split-charge-relays.co.uk/ gives lots of info.

When I moved my battery to the boot I bought an after market battery tray from ebay which I bolted in the boot, I then used a battery cable from an M3 to connect this to the under bonnet fuse box and ran another cable to the starter. I then used some 18mm MDF to make a box for the battery and covered it in boot carpet from a scrapped R45 so it looks factory fit. I wasn't installing a second battery but the principle is the same.

On my T16 maestro I did similar to above except I adapted the battery tray.

Smokey · 17-08-11, 04:22 PM

I suppose it begs an initial question of is it nessesary to do it for powering 3 screens, a laptop and an amp?

talkingcars · 17-08-11, 06:54 PM

Quote:

Originally Posted by Smokey

I suppose it begs an initial question of is it nessesary to do it for powering 3 screens, a laptop and an amp?

You'd be suprised how quickly that lot will run a standard car battery to below a point where it doesn't have enough power to start the engine, it will then properbly take you more time to get the car jump started than you would have done fitting the second battery.

Smokey · 17-08-11, 07:03 PM

Is there a power consumption figure for how much power a car battery can supply while alternator is running to guide me as to what can be connected safely?

Maxxed_Ross · 24-08-11, 06:36 PM

alot of landrovers use a split charging system due to the lights and winch drawing alot of power, but I went for an Optima Orange top battery in my last one (expensive but easily half the price of a good splitter system) and didn't have any bother with it at all.

I had to drag a friend out of mud in the middle of the night not long after fitting it, and even with all the spot lights on, the main beam, the winch running at full strain and the CB radio on (they draw crazy power for the size!) the lights didn't even dim. A highly impressive battery

Smokey · 24-08-11, 07:57 PM

Cool, may look in to that too. Cheers.