Extra 12 volt battery

[TOMMY47]

Anyone carry a cheaper 12v car battery in case regular battery won't start vehicle.
I have a conversion van made into a camper. Also have an extra interior battery, charged by solar, to run various( both 12v and 110) appliances. Also have some extra 12v plugs hooked up to van battery.
In my shakedown trip to Shenandoah NP, I encountered heavy fog for several days and ran both batteries too low to start van and needed a jump start. I was parked for a couple of days, not running van.
I will be traveling through the Northwest NPs and expect I will be without sun at times.
This is the system I'm going with and won't be changing it. Does the extra battery seem like a good alternative, just in case?

[intheburbs]

Sounds like you'd be better off installing a battery isolator to protect the starting battery.

If you don't want to do that, then I'd recommend something like THIS.

[Ozlander]

TOMMY47 wrote:

If you didn't charge the one battery in time, what makes you think you would charge the two batteries in time.

[TOMMY47]

Deep cycle--AGM--110ah. 100 watt solar, no room for more--usually is enough.
Inverter on the 110 stuff--extra 12v sockets on both. No 110v on the starting battery.
Major appliance is a 12v/110 small fridge. Use 12v volt when not hooked up.
I seriously thought about a jump starter but reviews had a lot of negatives. Seems, for about the same price or less, I could just get a cheap extra 12 volt battery.

[donn0128]

TOMMY47 wrote:
donn-- Read my post. It's very clear what occurred.

Sorry, I DID read your post. Your alternator is not sufficiently strong enough to keep the battery charged. But hey, what do I know Imjust an old school mechanic. Just add a bunch more batteries. Eventually youll figure out that you do not have sufficient charge capabilities.

[YC_1]

Ditto on buying a jump starter device. Much safer than using regular jumper cables.

[Dakota98]

Is the interior battery "deep cycle" ?? What size ?

How much solar do you have ?

You're using an inverter & running appliances utilizing both batteries for that purpose. What appliances are you running ?

[downtheroad]

How about a portable jump starter...instead of an extra battery.

Something like this LINK.

[TOMMY47]

choochoo. Yes. Solar only on the house. The thing that got me was the fog.

[TOMMY47]

donn-- Read my post. It's very clear what occurred.

[ChooChooMan74]

Is your house 12V system isolated from you chassis 12v system?

[donn0128]

Sounds like you need to get to the root of the problem. Why wont your alternator keep the batteries up?

[2oldman]

sure