12v Battery bank in my box truck

[SunEagle]

(flying high on battery power) Mike90250 (brings me crashing back to earth).
I gave it some thought and i think your right. taking the load off the battery bank and just buying fuel in the summer.

OK lets shift gears, my demands on the battery bank just dropped drastically with out the AC.
So i need to run:
12v LED strip lights (1 Amp)
12v Vent fans (1-2 Amp)
12v Pump for water (3 Amp)
Beefy Laptop has a 170watt brick (99% of the time probably only drawing less than 20watts)
Travel Ryobi Battery charger for my tools (unknown?)
Possibly a small flat screen TV (50 Watt)

Total 20 amp draw Max.

How many batteries would i need for that? Can I get by with 12v? Cable Size is no big issue, no run longer than 10ft-18ft.

It is usually better to determine your watt hour usage instead of your Amp usage.

Working backwards if you plan on using all those loads at the same time then on a 12volt battery it would come to 240 watt/hours (12v x 20 amps) for each hour you run them. So for 5 hours that would be 1200 watt hours which is pretty big daily load for a battery system. Since you should not use more than 20% to 25% of the battery you would need a battery that could supply between 5000 & 6000 watt hours.

But if you say that each LED uses 12 watts (12v x 1amp), the pump uses 36 watts (12v x 3 amps), etc. then you can calculate how many hours you would use each load. Add them up and you get close to your daily watt hour usage.

[Logan5]

You are Maxxed out, To parallel enough batteries to make airconditioning possible at 12 volts defies logic. you are building a rolling bomb! and chemical spill hazard. Now if you shop carefully, you can find everything you need that can operate from 24 and 12 volts. If you forgo the air conditioning, you can run a 24 volt battery bank and even have a refrigerator that runs on 24 volts. TV's can be obtained that uses only uses 7.5 watts for a 10" up to 40 watts for a 32" If you forgo an inverter all together you can save a lot on battery size. when you power items from heavy expensive batteries, high efficiency, reduce need, less is more.