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Anyone have advice for a generator powered battery charger?

Johnny.Cash!

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Building off the grid in Colorado. Thinking about a backup system for when weather turns bad and need to run generator to create power. Generator is 5500w and want to be able to charge batteries while generator is running. Batteries are LiFePO4 and require 14.4-14.6v to charge at 12v. It's a bank of 4 100ah batteries in series and parallel to create a 24v bank with 200ah. I've looked at some smart chargers but thinking it might be more efficient to use a power converter that puts out a constant voltage in correct range. Thoughts?
 
Hmm, specs on that say it puts out 27.2v. Battle Born recommends 14.4-14.6v per 12v or 28.8v per 24v. I guess the lower voltage would keep one from overcharging. Although looking at state of charge for their batteries 13.6v is 100%, so that would mean just slower charging right?
 
I use SLA batteries so Im not too familiar with the BB batteries but I would imagine they just wouldn't be topped off. Again im not sure how Battle Born works but I've found that that last Volt stuffed into the battery yields a very small percent of overall capacity.
 
I had just used mine this past weekend in a rain storm I didn't have time to fully charge batteries from my trucks inverter but it did save my bacon.

I didnt take a generator with me so I just hooked a 12v inverter to truck to power charger. I would of hooked truck directly to batteries but its a 24v system
 
Most generators have a 12V battery charge output. Check to see if the voltage/amps levels are acceptable for your batteries.
 
He has a 24 v system but could you alternate charging each half of the series of batteries? Might not be perfect but a possibility?
Yeah, saw the voltage difference, but the amps may not be there for multiple batteries. Depends on the genny.
 
Do the amps really matter wouldn't it just take longer?
Maybe.
I have to walk this back a bit.... just checked both my gennys, and neither has a 12VDC output... oops. I was sure the Honda 3500 did.

"Once, I thought I was wrong, but I was mistaken."
 
That generator does not have 12vdc. I do have one a 2000w generator that has a 12vdc @8amps, so that is a possibility although it would take quite a bit of time to charge a single 100ah battery.

Just to clarify that I'm thinking about this correctly.
The amount of amps will determine how quickly the batteries charge.
The voltage will determine how "full" the batteries get.

Not against unconnecting the batteries and charging them as individual 12v batteries and have been looking about the Noco Gen4. It is a 12v charger that can charge 4 batteries at once and send 10a to each bank. It charges at 14.2v and has an efficiency listed as 90% (the one listed above says >80%)

Still it would be nice to find a 24v charger so I don't have to disconnect things.
 
Morth, thank you. I'm wondering if you installed one of the IQ4-smart controllers or how do you keep the system from overcharging. And looking at both posts that recommend chargers they are both pointing towards IOTA chargers. On the page you linked to it also shows that it's capable of charging up to 28.4v during bulk charging which would fully charge the batteries. I'm thinking I shouldn't be too worried about efficiency since it's a backup system.
 
I got this one - https://www.amazon.com/gp/product/B07DP3X16F/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1. Same as recommended by Battle Born for LiFePO4 batteries. I can verify it does indeed back off the amps as full charge approaches. So look for something that has multi stage charging for the battery chemistry you have. I got mine with the intent on being able to charge the battery fairly quick so I don't have to run the generator all day, just a couple hours when needed to supplement the solar panel on cloudy days. So the gas supply lasts longer and I'm not making a bunch of noise all the time.
 
Thank you everyone. Ended up with the Iota DLS-24-25-x with the IQ4-x smart controller.

Looks like a newer version of the DLS; smaller form factor, it accepts 2 gauge wire, and comes with a 3 year warranty vs 2 years.
 
Am I missing something. Couldn't you simply install an mppdolsr hybrid 24v and have everything in one unit connected to generator?
 
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