Van to camper

Hi all. I've bought a tatty old Nissan Serena to convert to a campervan . I intend keeping it pretty basic, more of a motorised tent, but would like some advice on adding another battery for power. Would also appreciate hearing what others think is a 'must have'. I already have camping gear, chemical toilet etc.
In idiot speak too please as l'm not tech savy. Thanks

Take it to an auto electrician and ask them. More than a modicum of technical knowledge would be required to do it yourself.

The simplest way would be to get another battery of the same output as the one you already have, get some cables and fit it in parallel.
The problem is that being a campervan, you will be wanting one as a 'house' battery and the other to start the vehicle. Keeping them separate in use so you can still start the vehicle, but connected for charging purposes becomes the issue. If you can read wiring diagrams, do a google search and go from there.

I will tell you what I have so as to give you some ideas of what may suit you.
I use an old AWD Honda Odyssey with all the seats, except the front two, permanently removed. I have fitted a carpeted ply floor in the rear with a small amount of storage space under this floor. I carry heaps of food and water with me as well as a small fold up table for cooking on outside using one of those cheap single burner gas cookers that use 220gm cans of gas. I also have a small foldup seat for use outside when the weather is good. I don't use a second battery but only use my car battery for running two or three 11watt (or 13watt?) fluorescent ceiling lights for three or so hours each evening. These lights are quite efficient and give heaps of light. LED lights are more efficient than fluorescents but you need a huge number of them to match the light output of fluorescents.
I also operate my car radio as long as I like each day or night when I'm camped.
I also have a dash mounted LCD voltmeter that continually monitors my battery voltage. I also use an expensive battery with the highest performance that will fit in my car and will discard it when it's performance deteriorates. I almost always camp in secluded spots in the bush away from civilisation and am well aware of the trouble I would be in if I discharged my battery too much especially considering that my car is an auto
A second battery is a good idea if you have the space too mount it and essential if you want to run high current devices like 12 to 230Vac inverters.
If you are short of money and can tolerate operating manually the way to do it is to just connect the second battery(and it can be a battery with less capacity than the car battery) in parallel with the car battery and insert a switch in series with the EARTH lead of the auxiliary battery. To operate this system you ensure that this switch is ON when you are driving and OFF when you are camped. You have to ensure that all your ceiling lights etc are connected to this auxiliary battery(via fuses) of course.
In my opinion the best cheap vehicle for this type of camping is the Toyota Estima with Honda Odyssey being the second best choice although there are much better choices if you have the money.

keeping it really basic and keep the new deep cycle battery seperate, run LED lights, keep charger/solar panel at home for when you are not caming to charge the batt back to full.

I fitted lights from jay car. Cat no ST3915.
Led, very bright. You would only need 2. Low draw on your battery.
No switch required, just touch the case to turn on and off. Easy to wire in.
Also the poster earlier posted about a relay that charges your second battery. Very usefull.
Search VSR voltage sensative relay.
Aa solar.co.nz also have a handy wiring diagram to explain how it all works.looks complicated but really quite simple. honest.
Also a great place for batteries and solar panels if your really keen.

That's a good idea for a switch as it is easily able to handle high current should it be switched when the engine is running. You can buy them from any auto electrical supplier.

Some basic campers have a solenoid that is turned off & on by the ignition key to charge the house battery when the engine is running but separated from the starting battery when the key is turned off.

Thanks everyone exactly the sort of stuff l wanted to know. @mack l've already bought a Nissan Serena cos it was cheap.
A mechanic friend is going to do an overhaul for me and l was thinking of getting him to wire in the extra battery but wasn't sure how do - able it would be.

bella-If it was me I would be having a look at the professional type campers for inspiration.
What you need to plan around is the bed.
bed will need to go north/south so storage,cooking seating etc has to work around this.
mac has covered a shed load of stuff off but I will just add-Think LED as far as lighting is concerned.Led is a godsend for this kind of project as its low drain on the batteries.

Sorry for slow replies. Found some great sites and kept getting sidetracked then running out of time.
Much less daunted about wiring the extra battery now too. Found some really great ideas on this site and am thinking of doing an adapted north/south version (as you suggested kazbanz) of the camping box.
http://www.camper-van-fun.com/camping-box.html

One of these would be pretty nice too!
http://www.amdro.co.uk/boot-jump-camper-car/boot-jump-with-screens-water-bottle-p-43.html?osCsid=61m2dgqrc6s5hdilha8sibttv5