lithium conversion questions

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The only explanation I have for that is a high resistance connection between the batteries, how small are the wires, and is anything getting hot?
 
SOC by voltage is not very accurate for LFP. They have to get enough amp hours in to reach 3.5VPC or greater to reach full charge. Batteries in parallel need to be fully charged before connecting them, and then they should be wired so that current flows all the way thru both - pos side of one and neg side of the other to your bus or charging source.
 
Lou Schneider said:
I took your mention of a stock inverter to mean a stock converter instead, i.e. you only have one charger along with the engine alternator. Correct?

A DC to DC converter can boost the voltage as well as limit the current going to the batteries so with a little creative wiring it can solve both problems.

Disconnect the stock converter from the fuse board so the board is fed only from the batteries. Run a new line from the converter's output to the input of the DC to DC converter and connect it there along with the charging line from the vehicle's alternator. Take the output of the DC-DC converter to the batteries. The DC to DC converter will boost the voltage from your stock converter as well as limit the current when the alternator is running. It's OK to connect two DC sources together, the one with higher voltage will simply block the current from the one with lower voltage. It's AC where you can't connect two sources together without special precautions.
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So I was going to connect the house converter and battery/alternator to the same input on the DC to DC charger but am wondering if it would be better to connect the house charger to the solar input on the DC to DC charger. I'm not using that input anyways so does this sound like a better idea?
 
Why not connect the house charger directly to the LiFePo4 batteries? Does it output voltage outside the accepted range of the batteries?
 
Having a Lithium option marked on it by the marketing department does not matter if it outputs an acceptable voltage profile for a LiFePo4 battery. What brand and model is it?
 
I've got a new issue. I hooked everything together but I have no power to anything other than the jacks. The converter isn't plugged in so the batteries are powering the jacks but I have no power anywhere else. I have the main power disconnect turned to on so that's not the issue. I know its been months since I've used this rv so am I forgetting something here?
 
I checked the battery disconnect and no power going to it. I plugged shore power in and only microwave works. No lights or slideouts just jacks. The batteries show .4 amps draining continuously jumping to 20 amps when I power the jacks.
 
Can you double check that model number, google shows that as a power distribution board possibly used in the 4300 and 4500 series of Progressive Dynamics converters, both of which operate at 14.4VDC in boost mode and 13.6 in normal mode, making it possibly viable for LiFePo4 charging depending on the time outs, exact model, and size of the LiFePo4 battery bank.
 
Check by the battery, follow the positive cable and look for little rectangle Circuit Breakers. You may have two, one for the jacks and one for the 12V panel via the disconnect switch.
 
If you mean this things, yes there is one but it shows a voltage on both sides.
 

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Isaac-1 said:
Can you double check that model number, google shows that as a power distribution board possibly used in the 4300 and 4500 series of Progressive Dynamics converters, both of which operate at 14.4VDC in boost mode and 13.6 in normal mode, making it possibly viable for LiFePo4 charging depending on the time outs, exact model, and size of the LiFePo4 battery bank.
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I think those models have a lithium option, mine has a jumper to choose between lead acid and gel which switches the voltage from 13.6 to 13.2 with the jumper. As far as I can tell, mine is the pd9200.
 
I found the problem. The power cable that goes to the house connects to the same bolt that the battery isolation relay outputs to and the generator is connected to. I had this bolt connected to the dc to dc input so the alternator could input to the dc to dc when the ignition switch is on. I didn't realize that this is the same point where the house connects to get its power. So I disconnected the battery isolation relay out from this bolt and plan on connecting this relay out to the input on the dc to dc providing power to the dc to dc from the alternator when the ignition is turned on. I will then reconnect the bolt to the lithium batteries. The other option is to just skip the relay altogether and run the alternator line directly to the dc to dc. I also found that the dc to dc solar input requires a minimum of 14.5 volts to activate so I can't use that input for the house charger which maxes out at 13.6.
 
tombuchanan said:
I'd have to go out to find the model but I know it only outputs 13.6 volts.
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Unless it is a single-stage charger, that would be the float voltage only. Bulk and absorption rates are likely higher. If it's a single stage charger (instead of 3-stage), it probably ought to be replaced anyway, even if you stay with lead-acid batteries.

I'm not trying to talk you out of the DC-DC add-on; it's a more optimal method than an LA-style charger alone.
 
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