Typical charging amps for Lithium batteries from a stock converter?

[PS Cruisign]

Hello
I have a QD6000 on my Four Winds Super C.

Question. What are typical amps one would see when charging batteries?

My setup. House bank is two BB Lifepo4 lithiums of the 100AH variety. A Victron monitor. Generator operates normally to power coach in both AC and DC functions. Shore power also works.

When I run the generator to charge the batteries, it only seems to put out 9 to 12 amps over anything it is powering for battery charging. If I start the 6.7 diesel, the coach alternator will pump around 60 or so amps to the house batteries so I know the BMS on the batts will accept the amps.

Is this a typical amp output for the generator? Does it have something smart that regulates battery charging amps?

Thanks

[Bob Denman]

What's that formula?
Watts/volts = amps?

[PS Cruisign]

Bob, after further reading , should I find out how big the battery charger on the converter is? Perhaps that would be the start? Just didnt think that was a player unless using shore power.

[Judge]

Originally Posted by PS Cruisign

Hello
I have a QD6000 on my Four Winds Super C.

Question. What are typical amps one would see when charging batteries?

My setup. House bank is two BB Lifepo4 lithiums of the 100AH variety. A Victron monitor. Generator operates normally to power coach in both AC and DC functions. Shore power also works.

When I run the generator to charge the batteries, it only seems to put out 9 to 12 amps over anything it is powering for battery charging. If I start the 6.7 diesel, the coach alternator will pump around 60 or so amps to the house batteries so I know the BMS on the batts will accept the amps.

Is this a typical amp output for the generator? Does it have something smart that regulates battery charging amps?

Thanks

It is not your generator charging the batteries. Your generator is providing AC voltage to your Converter / Charger, which is charging the batteries.

You need to pull the specs on the specific Converter / Charger in your coach. I replaced my stock WFCO Converter with a Progressive Dynamics PD9260. The specs for it are:

Input: 105-130 VAC 60 Hz, 1000 Watts
Output: 13.6 VDC, 60 Amps

Also, a good Converter will have 3 or 4 charging modes: Boost, Normal, Storage and Equalization. The voltage and current will change depending on the charge mode the Converter is in at any point in time.

[Bob Denman]

I was reading your converter question: when Judge answered everything...

[PS Cruisign]

@Judge

Thanks. And thanks Bob. My wife and I started talking and we came to your conclusion probably as you were typing it. So I will eat a little humble pie there. Its the battery charger on the converter. I need to go see the specs on mine, however, that begs my next question.

If the charger senses battery voltage and say its a three stage charger (I will look tomorrow), then because I have Lithium, that rests at 13.1V, then is the charger thinking they are full? Hence the low amp input?

Thanks Bob and Judge

Maybe I should change the name of this thread for peeps who have switched over to Lithium. They might not scratch their heads like I did.

[16ACE27]

Originally Posted by PS Cruisign

@Judge

Thanks. And thanks Bob. My wife and I started talking and we came to your conclusion probably as you were typing it. So I will eat a little humble pie there. Its the battery charger on the converter. I need to go see the specs on mine, however, that begs my next question.

If the charger senses battery voltage and say its a three stage charger (I will look tomorrow), then because I have Lithium, that rests at 13.1V, then is the charger thinking they are full? Hence the low amp input?

Thanks Bob and Judge

Maybe I should change the name of this thread for peeps who have switched over to Lithium. They might not scratch their heads like I did.

Done!

[Bob Denman]

That's our Ace...

[Lt Keefer]

What Judge says

[GTM41261]

from Battle Born Batteries web site.

What is the maximum amperage I can charge
my batteries?
Our batteries allow a charge of 50 amps per 100-amp hour battery bank. For
more than one battery, you can simply take the entire amp hours of the bank
and cut it in half (e.g. a total of 300-amp hours can be charged at 150 amps)

[HarryS]

Your 9 to 12 amps at 120 VAC is actually 90 to 120 amps at 12VDC.

[Beau388]

Lead acid batteries need a three charge to reach maxim charge without boiling the water out or damaging the plates from heat. For longest life, the max charge current for deep cycle batteries should be 10% to 13% of the battery bank's capacity in amp-h. LA batteries can accept more current but at some risk. The ions can only move so fast from the cathode to the anode and back. This is particularly a problem in deep cycle AGM and Gel VRLA batteries.

LiFePo batteries all contain a battery manager that limits the max current the battery can accept or supply. The generally accepted max amperage is 50% of the batteries 12 volt amp-h capacity. LiFePo batteries only need a two step charger - bulk and float. Xantrex now makes a 150 amp @14.6 volt charger specifically made for large LiFePo battery banks.

[PS Cruisign]

To follow up on this thread, brought the rig home. Did a smack on the batteries by running air fryer, heater, fridge and ran them down to 75%. Started generator and sure enough... 10 amps. With generator running, i plugged in my shop battery charger. No change. They all get confused with lithium. I have currently a WF2055amp, three stage charger. Just wont work because of previously stated reasons.

Here is my solution.

Progressive Dynamics PD9160ALV 12V Lithium Ion Battery Converter/Charger - 60 Amp

Will get it installed and follow up. Amazon. 217 RV bucks

Cheers

[16ACE27]

Originally Posted by PS Cruisign

217 RV bucks

Cheers

Are RV bucks different from regular bucks?

[PS Cruisign]

Originally Posted by 16ACE27

Are RV bucks different from regular bucks?

Ah fell off the wagon. I own a sailboat too. We call a thousand a "boat buck" now worries.

[PS Cruisign]

Update

I got the Lithium charger/converter installed. Not too big a deal but it is slightly different in size than the old one.

Good news
It does what it said it will do.

Amps with generator running.

Nice

[Ejohn2317]

Agree. the Progressive Dynamics PD9260 is a great charger for lead and amg. Not for lithium. I believe they wont fully charge lithium to 14.5 v. So when Battle born say (drop in replacement).What they mean is you have to change your battery isolator to a BIM-225 so you don't fry your alternator. You also have to change the stock converrter charger to one that is designed for lithium batteries. FYI I installed 2x Renogy 100amh smart Batteries. $750 each. on amazon.

[DavidEM]

In addition to the good advice above, consider upgrading the wire size from your new converter/charger to the batteries. Often the voltage drop in that wire limits charging current. To achieve a voltage drop of less than a 1/4 V over a 10' distance from converter to battery, you need #2 gauge wire. Your original converter was probably wired with #6 gauge.

Do that and you may see the full 60A spec output. That should cut your generator running time significantly.

David

[Ejohn2317]

I also forgot to mention that you have to add a transfer switch. Between your sine wave inverter and the charger converter 110 circuit breaker in your power panel. if you don't already have one. If you don't when you operate your inverter you will be trying to charge your batteries from your batteries which won't work. A way around this is that when you operate your inverter you make sure that you turn off your circuit breaker to your converter charger.
Go Power! TS-30 30 Amp Automatic Transfer Switch