Buying advice for class C RV with 180w solar

[FreeFlyFreak]

Any 100 Ah (possibly 200ah) lifepo4 12v batteries that have cold temp shut off and self heating. Heating must be triggered by solar charge available, BUT heated by the battery itself, as I have only a 180w solar panel which is not enough power to heat in the heated batteries I have seen so far?

Current set up, Class C RV 130A alternator, Generator, which I prefer not to use, with converter with variable voltage, forget the exact settings but Lead Acid float for plugging in or bulk for generator (I am never plugged in), 180w solar panel, 20A pwm solar charge controller, 1 WLA starter battery, 2x WLA house batteries. Looking to replace my WLA house batteries with a single Lifepo4 house battery at some point.
I mostly camp dry on solar only, never had a problem with battery capacity so far so a single 100ah single Lifepo4 should replace 2x wet lead acid.

Thoughts?

 

[pollenface]

Yeah heaps, just do a search

Renogy, Ampere Time, LiTime, Redodo to name a few

Presume you mean 130a

Consider purchasing an adjustable mppt with low temp cut off (if desired) like a Victron 75/15 smartsolar & battery sense

 

[chrisski]

I mostly camp dry on solar only, never had a problem with battery capacity so far so a single 100ah single Lifepo4 should replace 2x wet lead acid.

Thoughts?

I'd reccomend replacing with battery capacity the same size. This gives you more energy to use, especially if the days get cloudy.

I can make my batteries last weeks, but if I am not the only one using it, others don't like to wake up to the RV at 41F, so on comes the electric blower motor for the propane heater, which uses a bit of power.

Heating must be triggered by solar charge available, BUT heated by the battery itself, as I have only a 180w solar panel which is not enough power to heat in the heated batteries I have seen so far?

If you take a look at power consumption for these batteries, unlikely consumption is that much your 180 watt panel can't handle.

cold temp shut off

I recommend a new SCC as mentioned with a temperature shut off for charging in case the battery gets too cold.

never had a problem with battery capacity

Also recommend getting a shunt so you know for sure. I've heard comments about like "my battery only got down to 10 volts, plenty of power left," or "I only took the FLA down to 40% tonight as measured by the SCC," which the first draining a battery so low is a terrible thing to do and the second, so 40% SOC is not good, but measuring with an SCC is not accurate.

Thoughts?

If the FLAs have been working for you, nothing wrong with keeping them.

 

[FreeFlyFreak]

Yeah heaps, just do a search

Renogy, Ampere Time, LiTime, Redodo to name a few

Presume you mean 130a

Consider purchasing an adjustable mppt with low temp cut off (if desired) like a Victron 75/15 smartsolar & battery sense

Yeah 130A alternator, so edited.
What is "battery sense"?
Mppt with low temp cut off is fine unless I want to crank the genset or Motor to drive, only an in battery low temp cut off would work for that

 

[FreeFlyFreak]

I'd reccomend replacing with battery capacity the same size. This gives you more energy to use, especially if the days get cloudy.

I can make my batteries last weeks, but if I am not the only one using it, others don't like to wake up to the RV at 41F, so on comes the electric blower motor for the propane heater, which uses a bit of power.

If you take a look at power consumption for these batteries, unlikely consumption is that much your 180 watt panel can't handle.

I recommend a new SCC as mentioned with a temperature shut off for charging in case the battery gets too cold.

Also recommend getting a shunt so you know for sure. I've heard comments about like "my battery only got down to 10 volts, plenty of power left," or "I only took the FLA down to 40% tonight as measured by the SCC," which the first draining a battery so low is a terrible thing to do and the second, so 40% SOC is not good, but measuring with an SCC is not accurate.

If the FLAs have been working for you, nothing wrong with keeping them.

Will for now, just planning ahead.

 

[FreeFlyFreak]

I'd reccomend replacing with battery capacity the same size. This gives you more energy to use, especially if the days get cloudy.

I can make my batteries last weeks, but if I am not the only one using it, others don't like to wake up to the RV at 41F, so on comes the electric blower motor for the propane heater, which uses a bit of power.

If you take a look at power consumption for these batteries, unlikely consumption is that much your 180 watt panel can't handle.

I recommend a new SCC as mentioned with a temperature shut off for charging in case the battery gets too cold.

Also recommend getting a shunt so you know for sure. I've heard comments about like "my battery only got down to 10 volts, plenty of power left," or "I only took the FLA down to 40% tonight as measured by the SCC," which the first draining a battery so low is a terrible thing to do and the second, so 40% SOC is not good, but measuring with an SCC is not accurate.

If the FLAs have been working for you, nothing wrong with keeping them.

Seems like all of the batteries I have looked at require more than the amps of my solar panel to allow for the heating function to work.
I have a shunt and battery monitor already.
I may keep 2 batteries hence my 100-200 a Lifepo4, but 1 100ah would give me the capacity I have now with 2x WLA batteries at 50% discharge.
I have never used more than 60% of my WLA, 99% of the time much much less.

 

[chrisski]

Seems like all of the batteries I have looked at require more than the amps of my solar panel to allow for the heating function to work.
I have a shunt and battery monitor already.
I may keep 2 batteries hence my 100-200 a Lifepo4, but 1 100ah would give me the capacity I have now with 2x WLA batteries at 50% discharge.
I have never used more than 60% of my WLA, 99% of the time much much less.

I don’t have a heater function. I did not realize it takes that much.

I shut charging off below 33 through the SCC and because record low never reaches below the min discharge temp, i have no use for it.

Please reference this for a build:

LiFePO4 Battery Warmer Install

This is my install of a custom set of battery warmers from Ultra Heat. I had contacted them through email asking about a warming profile for LiFePO4 batteries. They responded with a design to my specifications, including warming pads that fit my batteries exactly. While I initiated the...

diysolarforum.com

FLAs could be cheaper

 

[pollenface]

What is "battery sense"?

If you go the victron route, it's a sensing module that communicates battery voltage & temp (of the battery) with the charge controller