mixing battery types to start engine

[CosmickGold]

I have a regular automobile lead-acid battery on my van's engine, but the 4 large wheelchair batteries under the bed are gel, on a totally separate circuit, and charge by solar cells on the roof.

If the engine battery ran down and I needed a jump to start the engine, would it be safe to use the 4 batteries under the bed, connecting them with a long jumper cable to the engine battery? Or might there be some kind of incompatibility between battery types? Might I damage anything by doing that?

 

[abnorm]

Do you have jumper cables already ?........Wire ain't cheap !....and bed to battery could easily be 25'........or $50 worth

And then you need a space to store the wire roll................

I like a Jump Box.........we use ours more to start other people's rigs..........$59 or so .....(and you can use it as a portable power source....USB/Ciggy)

AND-to-answer-your-question......there's No problem using the house batteries as a jump source

 

[frater secessus]

would it be safe to use the 4 batteries under the bed, connecting them with a long jumper cable to the engine battery?

Yes, that would work.

If a dead starter batt is a real concern it might be a good excuse to add alternator charging to the rig, since many of those setups allow self-jumpstarting the vehicle. In this scenario you would press a button or turn the key rather than digging out the j-cables. Some of the setups actively maintain the starter battery when excess power is available from the house side, lessening the likelihood of a dead starter batt in the first place.

And of course alternator charging could contribute mightily to battery charging while driving.

 

[bullfrog]

All this assumes your solar system is 12 volt based, otherwise you would need to isolate one of the house batteries by disconnecting it before using jumper cables again assuming the house batteries are 12 volt.

 

[CosmickGold]

All this assumes your solar system is 12 volt based, otherwise you would need to isolate one of the house batteries by disconnecting it before using jumper cables again assuming the house batteries are 12 volt.

You are so correct! And yes, my solar-powered system is all 12V (except for the 5v converter used for charging USB items).