field 12v supply

[quarry44]

I'm currently using a 7.5ah gell cell,çause that's all i've got.Looking around for some thing a bit bigger capacity gave me a severe case of sticker shock!
Motorbike or wheelchair batteries are a horrendous price.How are they better than a simple car battery?I realize some are gell types,which are always higher priced,but even the small lead-acid batteries are quite expensive.
I tried running my charger off the car battery once,but had to get it push started when it was time to go home.
So a dedicated battery it will have to be.Just curious what other people are using.

[Denominator]

I do in fact use my car battery. But I keep the car running when I charge, or start it up now and then.
Set the car up with a positive and negative banana jack female in the back of the car, works well on my Chevy S10 Blazer, but then it also has a large battery

[quarry44]

It's funny you should comment on this now,yesterday I bought a car emergency starter pack.It was half price special,so how could I resist.I intend to use that as my charger supply in the field.It's got a 12Ah gell cell in it.That should be enough for a couple of charges.