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Home Forums General Discussion Deep Cycle Battery charge from my car? Re: Deep Cycle Battery charge from my car?


yes its possible here is what i did and yes i have used this setup

a lot over the years


too many batteries WILL put an excesive load on your alternator

if you run them flat basically you will fry the regulator and maybee even the

rectifiers in the alternator.

from expierience i would recomend not going beyond about 100 AH extra storage

with a normal car/small pickup alternator.

depending on how you set things up your alternator will only trickle charge

your extra batteries so 1.5 hours of driving will not add a lot to your xtra batteries.

there are ways to change the charge rate of your alternator and save your batteries and alternator etc but it takes too much technical knowledge

to set up for most people.I dont know if there is a easy comercial setup

to do this? honestly i have never used the rectifier based isolators and dont know if they will make the most of the charging capacity of a alternator?

but the fact still remains that working the alternator too hard (beyond designe specs) will cause problems.designe specs for most small vehical alternators are bringing a 50 to 100 amp hour battery up to correct charge rate very quickly.(when they try to do this to a large bank they are overloaded)

in short the alternator can put out huge amounts of energy but the regulator

and rectifiers are probably not up to the task right out of the box.

and then in the quest for power from an alternator you will run up against

belt friction/slippage and finally physical bearing strength.

in even shorter short LOL add another 10 amps to you standard alternator

work load and you will probably be ok 10 amps for 1.5 hours is 15 AH which

is not enough (nowhere near) to be running a fridge on a daily basis.

does that make sense?