Thread: Battery Recommendations?

Why do you think you need a second battery?

How would you link the 2 batteries together? Don't you have to run wire from the alternator to the back battery for it to charge?

Originally Posted by Pendragon445

Can anyone recommend a good type of battery to user to power a computer?
I currently have a M10000 system in the trunk with a cable going up front to the cig lighter for power. I'd like to have a 2nd battery in the trunk with the computer for power. Although I don't really want a fullsized car battery in the trunk if something smaller would do a good job as well.

Hi,
If you want to add a small and powerful second car battery i recommend you this one http://www.cardomain.com/item/STISPV35
and you need to add a diode isolator or solenoid isolator http://www.4wdmegastores.com.au/prod...noid_and_diode
to separate charging and discharging processes, this isolators will let you completely discharge one battery without discharging the staring battery.

The only power outlet in my car is 1 switched power cig outlet at the front of the car. I'd like to have the computer on a unswitched source. I was thinking a battery in the back would eliminate running wiring to the front battery and be the simpler solution.

I don't recommend you this, to add a second battery you need to exceed a 5000 watts power consumption or plan to listening to your stereo equipment like amp with subs etc.. without the engine running, this often leads to dead batteries.

Cheers,

If you add a second battery to the back you'll either have to wire it up to the existing battery/alternator on a tank circuit so it stays charged and doesn't run down your main battery (little complicated) OR you'll have to deal with charging that extra battery every so often if you just have it standing alone in back....which would get realllyyy annoying after a while.

Just spend an afternoon and run wire up to the front of the car (a 12V to the battery and another going to ACC/IGN 12v switched if you're using a smart power supply).

Originally Posted by ilyassx

I don't recommend you this, to add a second battery you need to exceed a 5000 watts power consumption or plan to listening to your stereo equipment like amp with subs ect.. without the engine running, this often leads to dead batteries.

Cheers,

Thanks , that's good to know, as I was thinking about adding a second battery.

If you want to run 2 batteries, ideally you want want to run a dual output alternator, but I doubt most would want to spend that much money. So if you want to use your single output alternator you will need either a diode isolator or a solenoid isolater. Still, the bottom line, if you don't want to ruin your batteries is to get a matched set. They need to be the same size and same age. Then you have to consider that your going to increase the load on your alternator. Your current one may not last very long trying to keep them charged up so most folks get a high output alternator of some sort. Typically like a 120-150amp. To do a dual battery setup isn't cheap. Figure the cost of 2 new batteries, isolator and a high output alternator to do it right. The big advantage is just a lot more engine off listening time.