car battery

**dooby_meu** · 07-13-2009, 01:01 PM

hi everyone.
i was wondering if someone can help me.
i've got a pc in my car dell gx280 p4 2.4 2x amp 1 to power my speakers witch is an alpine v12 and the 2 witch is a vibe class-D amp to power my pioneer 800rms sub. im using pw-200w psu. all works well the only problem is that i keep draining my car battery and the computer doesn't stay on for more then 15min max. i have my self a spair car battery and i would like to put it on the boot of my var were the spair wheel goes but i have read that cos is an acid battery. when charging it gives out nitrogen gas whitch is very flammable and ca explode. i am saving money to buy a yellow top battery but in portugal its very expensive. to minimise the risk of that happening what can i do and is it safe to do that at all? i have a 12v regulator and a battery isolator. i just want to power the pc from the 2 battery cos i do use my pc allot when the car engine is off but i dont need to my my sound system on. i just want to power the pc from the 2 battery and have my 2x amp's connected to the main car battery this way it will balance the power drain from bouth battery's. if it helps my car has a 90A alternator standerd and its a vw golf mk4 gti turbo

**hutacars** · 07-15-2009, 11:18 AM

Likely what is happening is the PSU is detecting that the battery is low and automatically shutting off the computer to protect the battery, and enable you to still start the car.

Lead-acid batteries only give off gas when they're charging, not when they're being used. So when you charge the battery (presumably you'd do this with a wall charger), leave the boot lid open and open the compartment to the spare tire, and this should provide adequate ventilation. You may want to place an exhaust fan there as well just to be sure.

Hope this helps.

**nalav** · 07-15-2009, 12:08 PM

When the car is running, the alternator will be charging the battery while it's being used. I know nothing of lead acid batteries, but if it gives off gas while it's charging, I would guess it would happen when the car is running, since it'll be charging the battery.

**dooby_meu** · 07-15-2009, 04:09 PM

i drive the car quite a lot so it will charge the extra battery with the car alternator. i want to install a 12v regulator is a 12v 10a regulator sutable to provide enuth power for my psu? psu is a PW-200-M, 200w output, 12v input DC-DC