Lithium batteries

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Hi new here have a ? I recently switched out my rv battery to two 100 ah lithium and changed converter. When plugged into shore power batteries charge fine about 14.5 volts, powered from generator I can’t get them over 13.2-13.5 volts. Any idea why? Using a predator 3500 watt inverter generator.
 
Can't imagine why. Unless you are not running the generator long enough.
 
So I replaced the converter in the rv with a lithium compatible. And I have run the generator for 4-5 hrs. I would think that would be long enough to charge them?
 
Is the generator connected to the same connector used for shore power? Or does it have its own connection point?
 
No display or lights. Goes from 10 volts to 13 in an hr or so but won’t get to the fulll charge.
 
Goes from 10 volts to 13 in an hr or so but won’t get to the fulll charge.
This is because 90% of your battery capacity is between 13.00V and 13.99V.
Depending on how big your battery is and how many amps you are charging at, it could be here at "13V" for quite a while, happily charging.

Its charging, just be patient and let it work.
LFP Voltage Chart.jpg
 
Maybe a poor AC power factor charger effecting inverter-generator peak output current. I would expect a normal inverter-charger would at least show an overload LED but maybe not Predator inverter-generator if they average the current sensing too much..

Poor power factor charger draws its AC power in high amperage, short bursts of peak current at peak of sinewave AC input voltage.
 
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Two things.

1- You still haven't answered the question about which converted you're using. If you want us to help you figure out what's going on, you need to give us some basic information here. As an example, if you're using a 30 amp converter, it will take six or more hours to get from 10 volts to 14 volts.

2- For the sake of your battery life, you really shouldn't let it get much below 12.5 volts. I would never let mine get to 10 volts. Realistically, there's not very much battery capacity between 10 volts and 12.5 volts with a lithium ion phosphate battery anyway. There is a big difference in how many years the battery will last though.

100 Proof
 
Hi new here have a ? I recently switched out my rv battery to two 100 ah lithium and changed converter. When plugged into shore power batteries charge fine about 14.5 volts, powered from generator I can’t get them over 13.2-13.5 volts. Any idea why? Using a predator 3500 watt inverter generator.
If you install a shunt, you will know how many amps are moving in and out of the battery, plus how many Ah's you have in the batteries. I have 3 of these now, accurate and price is right. https://www.amazon.com/gp/product/B0824X5MKM/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&th=1
 
Two things.

1- You still haven't answered the question about which converted you're using. If you want us to help you figure out what's going on, you need to give us some basic information here. As an example, if you're using a 30 amp converter, it will take six or more hours to get from 10 volts to 14 volts.

2- For the sake of your battery life, you really shouldn't let it get much below 12.5 volts. I would never let mine get to 10 volts. Realistically, there's not very much battery capacity between 10 volts and 12.5 volts with a lithium ion phosphate battery anyway. There is a big difference in how many years the battery will last though.

100 Proof
I’m using a progressive dynamics 55amp converter.
 
I’m using a progressive dynamics 55amp converter.
I was looking to "upgrade" to one of those from my PD4645 (not lithium aware) but the new PD models float at 14.4V which is waaaaay higher than i want to charge, let alone float.

But, its apparently a quality charger. Do you have a way to monitor the charging when its running on your generator? Clamp meter would be best.

I suspect it is charging. Perhaps the power from the generator is modified sine wave or otherwise not making the PD charger completely happy so charging slower? I dunno.
 
10 volts is flat dead. Best to start charging at 12.0 to 12.5 volts. 55 amps into 200 AH will take 4 hours minimum. 5 to 6 hours would not be unreasonable as the PD converter may not put full amps into the battery the entire time.
 
I was looking to "upgrade" to one of those from my PD4645 (not lithium aware) but the new PD models float at 14.4V which is waaaaay higher than i want to charge, let alone float.

But, its apparently a quality charger. Do you have a way to monitor the charging when its running on your generator? Clamp meter would be best.

I suspect it is charging. Perhaps the power from the generator is modified sine wave or otherwise not making the PD charger completely happy so charging slower? I dunno.
This is what I installed.
 

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