Alternator Upgrade for More Output ?

hi I'm looking to upgrade to a deep-cycle battery But I'm concerned about *under-charging* it.

Here is the spec on charging the high-end battery:

My car (Accord) alternator outputs, i think, only 12V-90A.

What is needed to increase voltage output ? replacing the alternator ?

thanks

A 90-amp alternator is a pretty husky alternator already. The deep-cycle battery is different only in that it can be drained further without risk of permanent sulphation, which destroys the average battery. Even a 30-amp alternator would recharge it, but would take a little longer. More likely you would burn out the alternator than hurt the battery, since alternators are sized to the car's maximum electrical requirements and a badly-discharged battery has such low resistance that it will pass lots of current. There's no alternator current cutout function in the regulator as the old generators needed to keep them from smoking out; they had much lower current outputs than alternators and were easily overloaded. If you need a bigger alternator you'd have to get one from a big truck, but making it fit would be fun. Cadillac (?) had a big alternator for a few years to run the electrically-heated windshields they had in some cars. The conductor was gold dissolved in the goop between the layers of glass.

Dan

thanks Mike so your alternator is the factory one and not some "souped-up" aftermarket modification or something ?

Correct. I got it off the shelf at a Canadian Tire parts store with a 5 year warranty back in 2000, so it is a rebuilt of some sort.

There are lots of us in the 4x4 community running dual batteries even with the stock alternators. No one has 'had' to upgrade from the little

65A units although I sure thought about it when I bought the last one. I just didn't feel like messing around so kept it stock. I did buy a rebuild kit for it for my parts box in case I smoked it out way back in the bush, but no need so far.

I run off road at night in the winter with the heater on full, the big lights on, stereo on, the wiper on and have to stop and winch. No issues.

Mike

thnaks Dan, "Burn out alternator" how ? due to overworking it ? Pass current to where ? back to the alternator ? can you explain more in laymans term I'm very ignorant in this field. thanks

thnaks Dan, "Burn out alternator" how ? due to overworking it ? Pass current to where ? back to the alternator ? can you explain more in laymans term I'm very ignorant in this field. thanks

Any car alternator worth its salt should be able to kick out its 100% maximum rating all day long, be that 60 amps or 120 amps. Charging a deeply dead battery will NOT hurt a healthy alternator, what will die is the battery because a deeply dead battery should be slow-charged back to life (10 amps or so max) rather than kicked back to life by dumping 90 amps into it. The battery may survive one quick-charge like this, but it will dramatically shorten its life. The other thing charging a dead, dead battery will do is find the worst connection between the alternator and battery (most corroded, not adequately tightened, etc.) and burn THAT up.

But what can burn the alternator up is if the battery itself is already done, so the alternator runs at 100% cycle all drive long charging the battery. The CS alternator on the wife's Beretta gets damn hot under normal conditions, I can't see it living long if it was working 100% trying to charge a battery that won't hold a charge.

Ray

It must be that GM alternators aren't worth salt.