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Charging Lifepo4 with shorepower

Jbarnes1719

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Trying find the right lifepo4 charger to incorporate into my rv for charging my 100ah batteries.
 
Trying find the right lifepo4 charger to incorporate into my rv for charging my 100ah batteries.
What voltage are your batteries? Use that in a search string on Amazon and Google. Based on the typical .5C charge you would not need one larger than 50 Amps. Prices vary by Amp capacity so if you have the time you can save some money by buying one that would charge slower.
 
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Welcome to the forum.

What converter does your RV have now?
Unless his RV is fairly new, it probably came with a 'converter' which does exactly that - Converts 120 VAC to a single voltage DC, typically 13 volts or so which isn't good for charging ANY battery - The voltage is low enough it will take forever to recharge even a small lead acid battery, but high enough that once it is fully charged, it will boil the water out of the battery

Any multi-step charger which advertises adjustments for lithium batteries should work fine. I would agree with a 50 amp unit. Usually when you're plugged into shore power it's for long enough (typically overnight) that 50 amps would recharge a modest size battery bank. The exception for a larger unit might be if he intended to use it while running his genset, then a larger unit might be preferred so charging would be faster . . . . but not so large it would cause problems starting his A/C unit

Don
 
What voltage are your batteries? Use that in a search string on Amazon and Google. Based on the typical .5C charge you would not need one larger than 50 Amps. Prices vary by Amp capacity so if you have the time you can save some money by buying one that
Trying find the right lifepo4 charger to incorporate into my rv for charging my 100ah batteries.
Welcome to the forum.

What converter does your RV have now?
Parallax 7355 power center with 55amp charge/ converter. But I realized that my voltage is 13.7 and will only charge them to 90%. Because of the age of the power center the options are few for a replacement charge/ converter.
 
What voltage are your batteries? Use that in a search string on Amazon and Google. Based on the typical .5C charge you would not need one larger than 50 Amps. Prices vary by Amp capacity so if you have the time you can save some money by buying one that would charge slower.
I am building two Calb 100 ah with overkill bms’s. I have solar but not the enough working on that too. But the hard part is getting them charged from shore power. After my searches so far I know I need at least 14.4-14.6 to bulk charge to reach 100% capacity.
 
I am building two Calb 100 ah with overkill bms’s. I have solar but not the enough working on that too. But the hard part is getting them charged from shore power. After my searches so far I know I need at least 14.4-14.6 to bulk charge to reach 100% capacity.



Personally, I would use it and see how it works.

The bigger issue is with wiring and distance. Most RVs have crappy wiring that has a substantial voltage drop between the converter and the batteries.

Here's an example of where I charged a CALB cell to 99.6% SoC @ 3.45V (13.8V):


The downside is that your charges will take longer.

The upside is that this is less stressful to the battery - longer life.

Get a good battery monitor (you need one anyway) and see how it works for you before you replace it.
 
I am building two Calb 100 ah with overkill bms’s. I have solar but not the enough working on that too. But the hard part is getting them charged from shore power. After my searches so far I know I need at least 14.4-14.6 to bulk charge to reach 100% capacity.
Should 4-3.2 volt cells. Max is I believe 3.6v.
 

Personally, I would use it and see how it works.

The bigger issue is with wiring and distance. Most RVs have crappy wiring that has a substantial voltage drop between the converter and the batteries.

Here's an example of where I charged a CALB cell to 99.6% SoC @ 3.45V (13.8V):


The downside is that your charges will take longer.

The upside is that this is less stressful to the battery - longer life.

Get a good battery monitor (you need one anyway) and see how it works for you before you replace it.
What would you suggest on the battery monitor? The Overkill bms’s have bluetooth and lot monitoring parameters.
 

Personally, I would use it and see how it works.

The bigger issue is with wiring and distance. Most RVs have crappy wiring that has a substantial voltage drop between the converter and the batteries.

Here's an example of where I charged a CALB cell to 99.6% SoC @ 3.45V (13.8V):


The downside is that your charges will take longer.

The upside is that this is less stressful to the battery - longer life.

Get a good battery monitor (you need one anyway) and see how it works for you before you replace it.
Also because of the age of the rv they used 6 gauge copper from the charger/converter to the batteries.
 
they were running 55amps thru a long length of 6awg wire??? toasty...
they were running 55amps thru a long length of 6awg wire??? toasty...
I believe because of the lead acid chemistry and the lack of a heavy load from powering the lights which only draws 10.17amps with every light on and the furnace blower motor with 11 amps draw they didn’t expect much. If this was all I needed then one 100ah battery would be enough. With everything running the rv draws around 2500 watts from shore power at 123vac.
 
I have a lot to learn as far as testing my own battery builds and cells. I have watched a lot of video’s from Will but I still don’t quite understand somethings.
 
Hmmm 2400watts with 12v systems would be 190+amp draw if you plan on running everything internal off battery!
have you considered putting the two batteries in series, it would cut your current demands in half.
 
Yes I would to the inverter. I actually don’t need to run the air conditioner. Mainly the furnace and lights and 1500watt inverter. I have more testing to do to find exactly where I am on my max loads. 2500 watts is absolutely everything running.
 
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