Portable solar panel to trickle charge vehicle battery

[whatsupdoc]

I have a Sterling B2B charger and solar panel fitted, but the latter only charges the leisure battery (and does a good job in doing that).

 

When touring, we do move around frequently, so the B2B works well in charging both batteries.

 

But at home there is a danger of the vehicle battery going flat, so I am considering a portable solar panel just for use at home.

 

(I did consider a battery master, but it seems there are problems with the B2B charger).

 

I think a small panel that plugs into the cigarette socket would be sufficient to keep the vehicle battery from going flat ...

 

BUT

 

On my VW T6.1 the cigarette sockets are always live (ie the ignition does not have to be on).

 

So would this be a problem in trying to use the sockets to charge the battery?

 

[747]

No, the socket would be fine.

 

You do not need a solar regulator when using a small panel. I believe you can go up to 30 watts before you need a regulator.

 

I have an 8 watt panel which is a bit on the small side for you but I use it to keep a spare battery topped up at home.

[witzend]

But you can save the trouble just make up a lead like this http://www.motts.org/BRIDGING%20FUSE.htm

Mine just has a clip connector on either end and I connect it when vans being left for any time eng battery not been flat for 12 mths now

[whatsupdoc]

Thanks.

 

The problem I would have with the bridging fuse is firstly getting the cable from the engine compartment into the van, and then having to run a cable to the back of the van where the leisure battery is located.

 

I'll try the solar panel - it's a relatively cheap outlay and it does seem to work.

 

[Charles]

Don't go too big without a controller, I've got a 5w monocrystalline panel on the car with no controller and after a few sunny days the battery voltage goes up to 15 odd volts.

 

Also bear in mind if you use a controller, in winter the controller can use more power than a small panel will make.

 

If the van's at home I would look at a small mains maintainer like the optimate units. That way the battery isn't being taken up to 14.4v every day.

[witzend]

whatsupdoc - 2021-05-27 5:11 PM

 

Thanks.

 

The problem I would have with the bridging fuse is firstly getting the cable from the engine compartment into the van, and then having to run a cable to the back of the van where the leisure battery is located.

you mentioned the cig lighter is permanently live so use that for the eng battery end