2nd Van Battery

[m4tty]

Hi,

When I got my van about a month ago the battery was flat. I tried 2 jump packs (a portable one and a mains one) but neither gave it enough to start. I was so eager and wanted the van I went and bought a new battery. Now I have charged the old battery for a few days, believe it or not its holding its charge well so ive got a spare transit battery.

The plan is to put it in the back and have it as a second battery to use for laptop power and maybe a small printer (to do certs and invoices on site). I wanted to know 2 things please.

1) How to connect new battery to van battery (its under the drivers seat so no probs with long leads) do I need a split charge relay?. Also is there a way of stopping the vans main battery going flat if the other went flat?

2) What size inverter would i need to charge laptop/use printer and maybe charge drill batteries (if its possible)

Thanks for reading and any advice appreciated.

Cheers

Mattut the kettle on

 

[Andy™]

split charge relay / B2B is recommended, but i dont bother with them. i have a 110AH battery in engine bay, and 3x 100AH leisure batteries under chassis. anything the can be left on without being noticed and could drain the battery (internal lights/sink etc) run through a low voltage cutout

when i get round to it, im going to add a relay on the cable between engine battery & leisure batteries. just trying to find a relay big enough to take a 50mm cable and the hundreds of amps it can sometimes take

i have a 1KW inverter, but for a while i had a 300w inverter. that managed to keep all battery chargers happy. sometimes 3 in use at the same time

 

[gordy71]

Sounds like Andy knows what he is on about so i wont echo... U could try another forum if i dare mention it on here... called volkszone for aircooled vdubs. Alot of people have leisure batteries on their campers and you might get some good advice on where to source any bespoke bits.

 

[NozSpark]

Andy... could you use an old starter solenoid... you know, the type that old Mini's used to have (not off a pre-engaged starter) IYKWIM

 

[Andy™]

Andy... could you use an old starter solenoid... you know, the type that old Mini's used to have (not off a pre-engaged starter) IYKWIM

my plan when i get to it is some 70A relays. probably 4. split the strands of the 50mm into 4 then sleeve & crimp them to fit onto terminals. i already have an ignition on feed ready to connect to it. just never had time

at the moment, if i want to isolate engine battery from leisure batteries, i just remove the fuse

 

[m4tty]

Have you got a sink in your van Andy?

 

[Badger]

oh no not going to mention that damned exporting of the earth and pipework are we again!! :innocent :innocent:^O:^O:tongue in cheek:Applaud:Applaud

 

[Andy™]

Have you got a sink in your van Andy?