2008 Grand Cherokee Dual Battery Setup??

[theendresult]

Hey everybody! Im new to the forum. Im going to be going on a adventure across canada and the us starting July 1st. Im converting my grand cherokee crd into somewhat of a expedition vehicle. Ive looked though a bunch of posts about wiring and I feel more confused than before. So Im hoping I can get some advice from some experienced travelers.

Im wondering if it would be wise to put in a 2nd battery? My power usage will consist of interior lights, arb fridge, laptop and cell phone charging and a webasto heater running at night. I will be working a few hours a day to fund the trip on my computer and phone so charging will be for 3-4hrs daily. I will be driving for 2-4 hrs daily to charge the battery so will one battery be enough or would 2 be recommended.

Also what size inverter do you think I need. All I know is I have a 55w cigarette lighter inverter and last time I plugged my laptop into it my laptop started to smell funny and the screen flickered lol. So Im assuming I need either a proper inverter or a bigger one? If I can get a proper cigarette inverter for my laptop then maybe I dont even need a bigger amp looking inverter? Im pretty sure the arb fridge has a cigarette lighter plug in adapter and I have one of those in the trunk area. After going though a few peoples threads Ive seen some running 3000 watt inverters. Seems like overkill for me?

Thanks for the help in advance:victory:

 

[orangeTJ]

Also what size inverter do you think I need. :

For a laptop, I'd recommend something about 400 watts.

 

[wrcsixeight]

I would not subject a vehicle starting battery to the usage you state, so I do recommend a secondary battery designed for cycling, not starting.

Your laptop in 3 hours might consume almost as much as the ARB will in 24 hours.

While it is nice to have an inverter to power other devices, a laptop car adapter for the laptop is the way to go. It just steps up the DC voltage from 12.xx to 16 to 21 volts dc depending on Laptop. An inverter goes from 12.xx v dc to 120 v ac and then the power brick reconverts that to 16 to 21 v dc for the laptop at a maximum of 90% efficiency.

My laptop car adapter uses 25 to almost 50% less electricity than If I were to use my 800 watt inverter to power the stock power brick.

Goto Amazon, type in your laptops make and model number and add "laptop car adapter"

Do note that a lot of ciggy plug receptacles are underwired and will suffer considerable voltage drop at that distance from the battery. Since the ciggy plug is a poor connection at best, the ARB fridge performance may suffer. The remedy is wiring it directly to the Aux battery over minimum 10 awg wire.