Charging batteries

[FIGJAM]

I want to recharge the 105ah agm battery that I use for my trike by hooking jumper cables to it from, the trucks battery instead of bringing a generator and charger to to do this.

Since most chargers charge at 2 to 6 amps, this would take a long time vs the trucks alternator which charges at 55amps at idle, which would be almost 6x faster.

My mechanic (40 years in the biz) says this will work.

So, no extra genny and chargers to haul, and the truck does the job running for an hour that would take a charger 6 hours.

Just wondering if anyone sees a problem that I may be missing.

Thanks.

[ygmir]

only issues I can see are:

is it an automotive battery? If so, it's not made to "deep cycle", so, that could be hard on it.
And, putting that many amps in, does create heat, and can possibly warp a plate inside.
Batteries like the slower charge.
Is there a way for you to take two batteries, and a solar charger?
Alternate batteries daily, so one has all day to charge slow from the sun?

Just a few thoughts.

[mudpuppy000]

As long as the battery can handle it it should probably work. Remember, that 55amps isn't all going to go to the extra battery, part of it is going to be used to run the engine/charge the battery on the car.

[FIGJAM]

It's a true deep cycle battery.

http://rebirthauto.com/o-8a31dt.aspx

The idea is to cut down on stuff I have to haul and I'm not quite ready to delve into solar yet.

Thanks Yg.

[FIGJAM]

As long as the battery can handle it it should probably work. Remember, that 55amps isn't all going to go to the extra battery, part of it is going to be used to run the engine/charge the battery on the car.

It's a turbo-diesel so I think most of the power will be going to the off battery.

The trike has a 30 mile range with that battery.

I might travel that much in the week.

[ConnieH]

Does your truck use more or less gas running for an hour than a genny? That would be something I'd consider, but it still sounds like a good idea - and thanks for suggesting it! Running a vehicle for an hour would be less annoying than a genny all day, provided your exhaust isn't pointed into someone's tent

[FIGJAM]

Vehicals at idle don't use much.

I'm guessing a gallon?

[phil]

> Just wondering if anyone sees a problem that I may be missing.

I have an 18 amp-hour AGM, and it provides a cable specifically to charge from the auto's cigar lighter. Your mileage will vary, of course, but my manual says:

Using the DC Charge Cable, xPower can be recharged as you drive. Simply plug either end of the DC Charge Cable into xPower's DC Power Socket, and the other end into the vehicle's cigarette lighter socket or 12 Volt accessory outlet. Most of the xPower's capacity will be restored in 1 to 3 hours while the motor is running. Although the automatic charge regulation circuitry in xPower does not operate with this charging method, most vehicle voltage regulators will ensure xPower is not overcharged. This charging method must not be sued with vehicles having abnormally high voltage electrical systems that operate above 15 Volts DC.

EDIT: One question: have you run your engine on the playa before? Does it blow dust out from under the vehicle because of the cooling fan?

[illy dilly]

It's a true deep cycle battery.

I'm not quite ready to delve into solar yet.

Thanks Yg.

Harbor Freight makes Solar Chargers. Again its Harbor Freight quality, which could mean nothing or could mean its a POS.
I have no experience with them, but have been looking at them. They also sell the battery isolator charge relay (I think its what they call it) that goes with it.

I'm going through a bunch of issues with the coach batteries, battery isolator, and Onan right now. I asked my RV guy a similar question. He said about "going from very low, to very high charge with out a battery charge regulator is not good for the battery. But once in a while, you just need the damn battery charged right now."
If that helps at all?

[FIGJAM]

Phill, good point about the dust.

The hight of the vehicle shoud make a differance and my 4x4 is much higher than a car. I did'nt notice more dust last time I was on the playa.

Illy, good to see you back.

The regulator in the alternator should protect from overcharging and regulates the charge at 14 volts, just pushes it at 55 amps.

Some of those HF solar chargers were for trickle charge maintenance, so read them carefully.

I think I'll call a golf cart place and see what charge rate the coreses use.

Thanks guys!

[illy dilly]

Illy, good to see you back.

Some of those HF solar chargers were for trickle charge maintenance, so read them carefully.

I think I'll call a golf cart place and see what charge rate the coreses use.

Thanks guys!

Thanks Fig, its good to get back on!

Thats a really good, idea. It didn't even dawn on me that golf carts charge pretty quick. I bet you could pick up a used golf cart charger on ebay. But then you're back to needing a 120v plug.

[ConnieH]

Some of those HF solar chargers were for trickle charge maintenance, so read them carefully.

exactly - I think you'd need a bigger solar system to completely charge a discharged deep cycle battery of your capacity, and if you are riding your trike during the day, solar ain't gonna work at night I'm looking at building a 60w solar array to charge deep cycle batteries for our bar, but like the idea of using a vehicle as a charge backup rather than a genny...I idled my VW last year after getting jumped and it didn't blow any dust around that was noticable.

[FIGJAM]

Ok, here's the latest info.

The chargers the courses use charge at a very high rate to begin with, then drop to a trickle to top off.

I don't care if it's topped off if I can go from a 50% charge to 90% in an hour, that will work great!

I also got the battery reps cell number, so I can verify this info when he's not so busy.

Oh. I bring 2 of those batteries. 1 for the trike and 1 for the camp lights, tunes, and cooler.

[illy dilly]

Ok, here's the latest info.

The chargers the courses use charge at a very high rate to begin with, then drop to a trickle to top off.

I don't care if it's topped off if I can go from a 50% charge to 90% in an hour, that will work great!

I also got the battery reps cell number, so I can verify this info when he's not so busy.

Oh. I bring 2 of those batteries. 1 for the trike and 1 for the camp lights, tunes, and cooler.

Then for tunes and stuff, do you throw an inverter on the camp battery? Or run it right off the battery some how?

[FIGJAM]

I try to make everything run on 12 volt to keep it simple.

May install a car stereo in the new playapod or just install one in a box to make it portable.

I bought a 3000/6000 inverter for $120 off CL to run my 35 pound jack hammer on the job instead of hauling a genny (have to run the truck when in use) so I'll use that for my pancake compressor to presurize my water tank.

[Token]

Modern car alternators are regulated devices and provide demand based power. i.e. the rotor is energized based on load.

Your battery will charge just fine. It will charge at a high rate at the beginning and then trail off.

[Freesponge]

Remember too that alternators are designed to maintain one battery and run accessories only. Repeated chargings of a dead agm battery may reduce the life of your alternator.

Just remember that if you have a 12 aH battery, divide the total time by two because you never want to drain your battery to 0. Using only half will extend the life of the battery and be easier on your cars alternator.

[ygmir]

IIRC, there is a camp, or more, that offer solar battery charging.
I forget the name, but, they've posted here. And, I think I saw at least one station last year sort of near center camp.

[Token]

Remember too that alternators are designed to maintain one battery and run accessories only. Repeated chargings of a dead agm battery may reduce the life of your alternator.

Not true. That only has merit for a generator, not an alternator.

In addition, Figs has a full size diesel pickup with a beefy alternator. These were designed to accommodate dual battery operation.

Just use fat cables and you're fine.

[illy dilly]

This is all really good info and has me rethinking a few things.
Trying not to change the subject too much. Could you pull current right off a stand alone generator into a batter? Instead of plugging a trickle charger into the AC ports on the gene.

The Onan in our RV is rated (or maybe built?) for 12v DC. But most generators put out AC current, right?

Could you come straight off the contacts of the generator and into a batter? Or would that be trying to charge a DC batter with an AC current?

[FIGJAM]

Not sure about the ac/dc, but my concern would be the unregulated power from the genny overchargeing the batteries and ruining them.

How are you gonna know when to stop charging?

Those true deep cycle batteries are pricey and I want a failsafe to protect them.

Thats why I like the idea of useing the alternator cause it has the built in regulator to prevent over charging.

[illy dilly]

Good point!
(God I'm glad I ask this shit, before I go trying it!)

O Well, back to charging it off the power strip. Probably just charge the battery when no one is using the sound system.

[gyre]

It is possible.

Not a good idea.

[illy dilly]

It is possible.

Not a good idea.

Like so many other things!

[Major Krash]

my Honda EU2000 has a 12v dc plug, and you can buy a battery charging cable that plugs into it...but I assume it just gives a steady output...

[FIGJAM]

my Honda EU2000 has a 12v dc plug, and you can buy a battery charging cable that plugs into it...

Many generators have those, but how many amps does it charge at?

8 amps.

And that outlet is not regulated!

[FIGJAM]

Look at the "key specs" on this charger.

http://www.northerntool.com/shop/tools/product_200331941_200331941

If it can charge at 80 amps, it would seem that I can charge from my alternator with no problem.

[CapSmashy]

my Honda EU2000 has a 12v dc plug, and you can buy a battery charging cable that plugs into it...but I assume it just gives a steady output...

The 12 volt charger port on the EU is just about worthless.

You are better off buying a multistage smart charger and plugging it into the generator to charge your batteries. Faster and protects the battery with a proper charger.

[ibdave]

my Honda EU2000 has a 12v dc plug, and you can buy a battery charging cable that plugs into it...but I assume it just gives a steady output...

The 12 volt charger port on the EU is just about worthless.

You are better off buying a multistage smart charger and plugging it into the generator to charge your batteries. Faster and protects the battery with a proper charger.

It's what I do in camp..

[teardropper]

I try to make everything run on 12 volt to keep it simple

Agree, that. I had a 700 watt inverter go to idle after 20 minutes of operation on the playa and couldn't get it to work. Worked at home. This year I'll have all 12 volt. No inverter 'cept a little 150 watter for small electronics...

Really understand the 'one less thing' idea. Have you tried it at home?