Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×


Reply
 
Thread Tools Display Modes
Old 02-27-2024, 09:02 PM   #1
Member
 
Join Date: Aug 2023
Posts: 58
another lead to lithium question

I am considering installing a 100aH lithium battery in place of my lead acid. This is in consideration of some 10-hour travel days, some 4 to 6 hours stops to sight see, and the 12-volt refrigerator.
I am starting doubt the lead acid can carry the load in my 2023 RP196. I don't know the size wire is in the camper, but it is probably 8awg as that seems to be what Forest River installs on this size trailer. The inverter is in the rear and the battery on the tongue, probably 20 feet from charger to shut off switch. The bottom of the trailer is completely enclosed so I really don't want to add a larger gauge wire.

My question is can I install some type of amp limiter between the charger and the battery? I know it will increase the charge time but I will be plugged into a land line at least 12 hours every day. I also have the 190 solar panel and charger that came with the camper, both lithium capable and may want to add a second 100aH battery in the future.

Thanks in advance.
wlfclf2000 is offline   Reply With Quote
Old 02-27-2024, 09:22 PM   #2
Senior Member
 
Join Date: Aug 2019
Location: Central NJ
Posts: 1,015
Why try to limit the current? First off the built in convertor can only output whatever amps its rated for 35-65 usually for the WFCO convertors. Second the 20' of #8 wire will limit the max amount that your convertor will try to put out because of the voltage drop over that distance. Most people try replacing the factory wire with a larger one to get closer to the max rate.

Jim M.
__________________
2020 Flagstaff Super Lite 26RBWS
Former: 2017 Rockwood MiniLite 2104S
2015 Silverado 2500HD 6.0L Gas
jimmarako is offline   Reply With Quote
Old 02-27-2024, 10:12 PM   #3
Member
 
Join Date: Aug 2023
Posts: 58
Quote:
Originally Posted by jimmarako View Post
Why try to limit the current? First off the built in convertor can only output whatever amps its rated for 35-65 usually for the WFCO convertors. Second the 20' of #8 wire will limit the max amount that your convertor will try to put out because of the voltage drop over that distance. Most people try replacing the factory wire with a larger one to get closer to the max rate.

Jim M.
Thank you for the reply. I am aware of the voltage drop but also aware that means heat. I am willing to live with the voltage drop but less willing to risk the heat. If I can limit the voltage the lithium battery can drawl at the battery to levels the wire can handle, will that fix the heat problem? If so, does anyone know of a good way to limit the voltage?
wlfclf2000 is offline   Reply With Quote
Old 02-27-2024, 10:49 PM   #4
Senior Member
 
Join Date: Aug 2019
Location: Central NJ
Posts: 1,015
Quote:
Originally Posted by wlfclf2000 View Post
Thank you for the reply. I am aware of the voltage drop but also aware that means heat. I am willing to live with the voltage drop but less willing to risk the heat. If I can limit the voltage the lithium battery can drawl at the battery to levels the wire can handle, will that fix the heat problem? If so, does anyone know of a good way to limit the voltage?
Well, #8 wire is good for at least 50 amp which is probably more than your convertor will put out. It will not get hot at that load... maybe warm if that. I'm going to say you are overthinking this. Even with the lead battery in place it could have pushed 50 amp of current.

Jim M.
__________________
2020 Flagstaff Super Lite 26RBWS
Former: 2017 Rockwood MiniLite 2104S
2015 Silverado 2500HD 6.0L Gas
jimmarako is offline   Reply With Quote
Old 02-27-2024, 11:47 PM   #5
Member
 
Join Date: Aug 2023
Posts: 58
Quote:
Originally Posted by jimmarako View Post
Well, #8 wire is good for at least 50 amp which is probably more than your convertor will put out. It will not get hot at that load... maybe warm if that. I'm going to say you are overthinking this. Even with the lead battery in place it could have pushed 50 amp of current.

Jim M.
Thanks again for your time.

The charger is capable of 55 amps and I plan to sleep in this camper so I can't help overthinking this. Will a 40 amp d/c to d/c charger work to reduce amps in this situation? I think I read this is the best amperage to prolong lithium battery life.
wlfclf2000 is offline   Reply With Quote
Old 02-28-2024, 12:51 AM   #6
Senior Member
 
Join Date: Aug 2019
Location: Central NJ
Posts: 1,015
Quote:
Originally Posted by wlfclf2000 View Post
Thanks again for your time.

The charger is capable of 55 amps and I plan to sleep in this camper so I can't help overthinking this. Will a 40 amp d/c to d/c charger work to reduce amps in this situation? I think I read this is the best amperage to prolong lithium battery life.
Yes, a DC-DC charger is about the only way I can think of to easily and with few problems reduce the current draw from the convertor. A 40A one will save you like %20 on the current.

Anything below 1C charge rate (probably 100A in your case) will not harm the battery. Shallow discharge/charge is the best. Ideally keeping the battery at %50 +- %10 is very good for it... but totally unpractical in real world.

OK.... I'm not sure of your background, or camping experience or fears of electricity... this is not meant as an insult, but more informational.

I sleep in my camper 40+ nights each year. The thousands of members on this forum sleep in their campers many nights with their children and pets. Why do we sleep so well while our convertors are cranking away all night? Because there is no risk of the wire from the convertor to the battery overheating and catching fire. Why would it? The RV manufactures are cheap, but do you think they would give you substandard wire?

#8 wire is rated for 50-55amps by NEC. In free air, which is what the wire in your trailer would most likely resemble, it can carry 100A. And this is not the point where it will burst into flames if you go 1A over.

Your convertor is rated at 55A. Thats the most it will (and can only) do under ideal conditions which probably will never be achieved. Even if the battery begs for 100,200,300 amps of current, it will only get 55. If you roll in with a near 0% state of charge on your battery, in one hour you will be at 55%. Current will start tailing off at some point so two hours maybe 80%, three hours 99%.

Maybe if you had like a 600-800ah battery bank, and needed to run full out at 55A for 10-12 hours, in the hot Arizona desert, there might be some concerns. Otherwise I'd suggest save you money and time and just go out and enjoy camping.

Good luck with what you decide.

Jim M.
__________________
2020 Flagstaff Super Lite 26RBWS
Former: 2017 Rockwood MiniLite 2104S
2015 Silverado 2500HD 6.0L Gas
jimmarako is offline   Reply With Quote
Old 02-28-2024, 08:54 AM   #7
Senior Member
 
Join Date: Apr 2022
Location: Tarpon Springs FL
Posts: 3,471
if you are going to plug into 120v each night
+ you driving 10 hours
+ you have some solar

Battery won't go flat...
when you hookup truck in morning the battery will be 100% from shore power charging

Make sure your 7 pin POWER wire........... is putting out the correct voltage
The standard 7 pin POWER wire should keep up with the fridge while you are driving
SOLAR will assist the 7 pin if/when it is sunny

My 12v fridge is only drawing about 5 amps when it is cold and it's compressor is running
The alternator charging should keep the fridge running without any drain from the battery

When you STOP the truck for lunch , sight seeing etc... battery will handle that

--------------------------------------------------------------------------
at night on 120v shorepower
you'll probably only see an average of 20amps or less going into the battery
it will only produce HIGHER amps if the battery is heavily discharged.

being plugged in overnight... more than enough time to charge the battery back to 100%

------------------------------------------------------------------

sight seeing.... even if the fridge draw is high because you bought a bunch of room temperature food from the store.. it will be a max 8 -10 amps amps
a 100ah liffpo4 battery will last about 14 hours if you turn off all the lights etc

when you get to campsite with power it will recharge and the cycle will start all over again.

Look at feasibility of adding more solar.... then you can probably camp all night without 120v power... you can save a bunch of money while travelling by not paying for powered sites...

------------------------------------------------------------------------

I just put 2 x 100ah batteries into mine so can camp for at least 2 days with fridge and no 120v connections
Cost me 400 for batteries and another 50 for cables and tiedowns
__________________
Tarpon Springs FL
2022 Salem 24RLXL
Aussieguy is offline   Reply With Quote
Old 02-28-2024, 10:05 AM   #8
Member
 
Join Date: Aug 2023
Posts: 58
[/QUOTE]

OK.... I'm not sure of your background, or camping experience or fears of electricity... this is not meant as an insult, but more informational.

I sleep in my camper 40+ nights each year. The thousands of members on this forum sleep in their campers many nights with their children and pets. Why do we sleep so well while our convertors are cranking away all night? Because there is no risk of the wire from the convertor to the battery overheating and catching fire. Why would it? The RV manufactures are cheap, but do you think they would give you substandard wire?

#8 wire is rated for 50-55amps by NEC. In free air, which is what the wire in your trailer would most likely resemble, it can carry 100A. And this is not the point where it will burst into flames if you go 1A over.

Your convertor is rated at 55A. Thats the most it will (and can only) do under ideal conditions which probably will never be achieved. Even if the battery begs for 100,200,300 amps of current, it will only get 55. If you roll in with a near 0% state of charge on your battery, in one hour you will be at 55%. Current will start tailing off at some point so two hours maybe 80%, three hours 99%.

Jim M.[/QUOTE]

I have a lot of experience camping but that was 15 years ago (I camped and traveled for 25 years before that). We never thought about or knew about carrying anything more than lead acid because that's all we had.
Things have changed and I am just trying to understand the technology I am using. There are many stories on the internet about people "burning down the house" using Lithium batteries wrong.
Thanks for your help.
wlfclf2000 is offline   Reply With Quote
Old 02-28-2024, 10:11 AM   #9
Member
 
Join Date: Aug 2023
Posts: 58
Aussieguy

Thanks for your feedback.
wlfclf2000 is offline   Reply With Quote
Old 02-28-2024, 10:38 AM   #10
Senior Member
 
Join Date: Aug 2019
Location: Central NJ
Posts: 1,015
Things have changed and I am just trying to understand the technology I am using. There are many stories on the internet about people "burning down the house" using Lithium batteries wrong.
Thanks for your help.[/QUOTE]

Well, there's the issue.. never trust the internet.

Those "stories" of people burning down the house are mostly cheap electric bikes, or other no name batteries being hacked into stuff not meant for lithium.

The batteries used in RV's are generally safe as they come... some say safer than lead acid because they don't leak poisons gas then explode. Its very common for people to mount their lithium batteries inside the trailer, under the bed.

Do more research on this site, or check out Will Prowse who has dozen of videos testing and pulling apart batteries.

https://www.mobile-solarpower.com/li...batteries.html


Jim M.
__________________
2020 Flagstaff Super Lite 26RBWS
Former: 2017 Rockwood MiniLite 2104S
2015 Silverado 2500HD 6.0L Gas
jimmarako is offline   Reply With Quote
Old 02-28-2024, 11:14 AM   #11
Senior Member
 
Join Date: Aug 2023
Location: Bayou Vista, TX
Posts: 121
Quote:
Originally Posted by wlfclf2000 View Post

I have a lot of experience camping but that was 15 years ago (I camped and traveled for 25 years before that). We never thought about or knew about carrying anything more than lead acid because that's all we had.
Things have changed and I am just trying to understand the technology I am using. There are many stories on the internet about people "burning down the house" using Lithium batteries wrong.
Thanks for your help.
The stories you hear of houses burning down, laptops / phones catching fire, etc. are where Lithium Ion / Lithium Polymer batteries are used. LiIon / LiPO are very susceptible to thermal runaway if they're charged improperly, or are punctured.

However, the batteries used in RVs are Lithium Iron Phosphate (LiFePO4) and are incredibly resilient. Often even a puncture will only result in some smoke, but no uncontrolled flame. The newer ones also have built in thermal protection, and you can get them with high and low temperature shutoff to protect the battery in extreme temperatures. You'll be fine just replacing your lead acid with LiFePO4.
__________________
2021 Forest River Wildwood 171RBXL
Towed by 2018 Toyota Tundra TRD SR5
reidfo is offline   Reply With Quote
Old 02-28-2024, 12:35 PM   #12
Member
 
Join Date: Aug 2023
Posts: 58
I'm going to just drop it in and see what happens. I live in Maryland so need to wait a few weeks to make sure no overnight freeze but the battery I bought does have low temp shut off. I have to check if my charger is auto sensing or if I need to hit a switch. I know I need to change the solar but that's easy.
Thanks all.
wlfclf2000 is offline   Reply With Quote
Old 02-28-2024, 12:40 PM   #13
Senior Member
 
Join Date: Dec 2021
Posts: 548
My experience may help the OP. When I changed to LFP I was disappointed with the converter charging. As noted, the wire size limits the current. The same is true with the TV charging. I get about 8A out of my F150, again limited by wire size. So I didn't burn up my converter or my alternator like I had read on the internet.

If you are just swapping out batteries there is no need to change wiring because your loads aren't changing. A different story if you are thinking of a bigger inverter or something.

Driving down the road, you get TV charging and your 190W of solar should contribute as well to keep up with your refrigerator load.
__________________
2019 Palomino Solaire 147X
2013 Ford F150
TacomaJoe is offline   Reply With Quote
Old 02-28-2024, 01:21 PM   #14
Senior Member
 
Join Date: Apr 2022
Location: Tarpon Springs FL
Posts: 3,471
I also found factory wiring was an issue ...... but more so on the connections

got much better charging performance from the converter
by tracking down the factory connections and "fixing" them

removed paint from frame and swapped out some lugs
very little cost but a PITA to work under the trailer.

now getting approximately 40 amp charging when batteries are 60% discharged.
__________________
Tarpon Springs FL
2022 Salem 24RLXL
Aussieguy is offline   Reply With Quote
Old 02-28-2024, 01:28 PM   #15
Senior Member
 
Join Date: Nov 2017
Location: Dayton Ohio
Posts: 3,596
In your case it will be easy. Just put in a new battery bank and reset the solar controller and converter to lithium. The converter sort of does not matter.

However, I would measure the battery box carefully and install the biggest battery possible. I have two SOK 206 ah batteries. They have heaters and a battery monitor built in. Under $1000.

100 amps of lithium will likely get you through a night. But, not by much. A second night is possible but, likely not. The fridge is a big user. So is a furnace or cpap. Batteries are the weak link. Inverters are big users.

I would want 200 ah of battery or more. On long trips we often boondock or Harvest Host a lot. Cheap and fast.
tomkatb is offline   Reply With Quote
Old 02-29-2024, 09:19 AM   #16
Senior Member
 
Join Date: Jul 2017
Posts: 4,056
Quote:
Originally Posted by wlfclf2000 View Post
I am considering installing a 100aH lithium battery in place of my lead acid. This is in consideration of some 10-hour travel days, some 4 to 6 hours stops to sight see, and the 12-volt refrigerator.
I am starting doubt the lead acid can carry the load in my 2023 RP196. I don't know the size wire is in the camper, but it is probably 8awg as that seems to be what Forest River installs on this size trailer. The inverter is in the rear and the battery on the tongue, probably 20 feet from charger to shut off switch. The bottom of the trailer is completely enclosed so I really don't want to add a larger gauge wire.

My question is can I install some type of amp limiter between the charger and the battery? I know it will increase the charge time but I will be plugged into a land line at least 12 hours every day. I also have the 190 solar panel and charger that came with the camper, both lithium capable and may want to add a second 100aH battery in the future.

Thanks in advance.
Better check the lithium battery for adding a new one to a used one . seems most recommend if you are going to run more then one they should both be new or at least of the same age and use .
MR.M is offline   Reply With Quote
Old 02-29-2024, 04:45 PM   #17
Member
 
Join Date: Jul 2023
Location: Waynesville, NC
Posts: 88
Quote:
Originally Posted by wlfclf2000 View Post
I am considering installing a 100aH lithium battery in place of my lead acid. This is in consideration of some 10-hour travel days, some 4 to 6 hours stops to sight see, and the 12-volt refrigerator.
I am starting doubt the lead acid can carry the load in my 2023 RP196. I don't know the size wire is in the camper, but it is probably 8awg as that seems to be what Forest River installs on this size trailer. The inverter is in the rear and the battery on the tongue, probably 20 feet from charger to shut off switch. The bottom of the trailer is completely enclosed so I really don't want to add a larger gauge wire.

My question is can I install some type of amp limiter between the charger and the battery? I know it will increase the charge time but I will be plugged into a land line at least 12 hours every day. I also have the 190 solar panel and charger that came with the camper, both lithium capable and may want to add a second 100aH battery in the future.

Thanks in advance.

I think your 8awg wire run will provide its own "amp limiter" and you don't need to worry about anything. And I'm not talking about resistance causing heat and "consuming" the current. I'm talking about resistance affecting the charge curve of the Li batteries and creating a natural limiting function.

The assumed 20ft run of 8awg stranded wire has a resistance of 0.0134 ohms. Doesn't sound like much, but it's significant. Assuming a charging voltage of 14.4 from the Li-ready charger, and assuming the battery tries to draw the maximum charge current of 55amps, the voltage drop across this length of wire will be 0.74VDC. Therefore the charging voltage present across the battery terminals will only be 13.66VDC. At this much lower voltage the Li battery will not draw anywhere near the maximum charge current.

As the current drops, the charging voltage present at the battery will increase causing the battery to sink more current. There will be a sweet spot somewhere along the charging curve where the voltage drop / charge current limiting will equalize. No idea how to calculate where that spot will be, and it will move along the curve constantly as the SoC of the battery changes.

But the takeaway here is that you can rest assured you will not overload that 8awg wire run with a maximum current flow.

In the case where the wire run is only 10awg, I think there's still no worry. In that case the math yields a voltage drop at 55amps of 1.20VDC, resulting in a battery charging voltage of only 13.2VDC, thus limiting the current flow even more.
__________________
2023 r-pod RP-192
not enough solar capacity
not enough battery capacity
not enough towing power
"Never underestimate the power of human stupidity."
-Lazarus Long
jlankford is offline   Reply With Quote
Old 02-29-2024, 04:51 PM   #18
Member
 
Join Date: Jul 2023
Location: Waynesville, NC
Posts: 88
Quote:
Originally Posted by wlfclf2000 View Post
I am considering installing a 100aH lithium battery in place of my lead acid. This is in consideration of some 10-hour travel days, some 4 to 6 hours stops to sight see, and the 12-volt refrigerator.
I am starting doubt the lead acid can carry the load in my 2023 RP196. I don't know the size wire is in the camper, but it is probably 8awg as that seems to be what Forest River installs on this size trailer. The inverter is in the rear and the battery on the tongue, probably 20 feet from charger to shut off switch. The bottom of the trailer is completely enclosed so I really don't want to add a larger gauge wire.

My question is can I install some type of amp limiter between the charger and the battery? I know it will increase the charge time but I will be plugged into a land line at least 12 hours every day. I also have the 190 solar panel and charger that came with the camper, both lithium capable and may want to add a second 100aH battery in the future.

Thanks in advance.

BTW, did you really mean to write "The inverter is in the rear and the battery on the tongue, probably 20 feet from..."?

I would be much more concerned with the wire gauge of the battery-to-inverter connections of a 20ft run. I assume you meant there is approx 20 ft from battery to the converter/charger and that this post has nothing to do with your factory installed inverter? I recall you have the same 2000W WFCO inverter that I do in an RP-192. I assume the factory used the same 5ft long 2-0awg cables in yours as in mine?
__________________
2023 r-pod RP-192
not enough solar capacity
not enough battery capacity
not enough towing power
"Never underestimate the power of human stupidity."
-Lazarus Long
jlankford is offline   Reply With Quote
Old 03-01-2024, 11:14 AM   #19
Member
 
Join Date: Aug 2023
Posts: 58
Quote:
Originally Posted by jlankford View Post
BTW, did you really mean to write "The inverter is in the rear and the battery on the tongue, probably 20 feet from..."?

I would be much more concerned with the wire gauge of the battery-to-inverter connections of a 20ft run. I assume you meant there is approx 20 ft from battery to the converter/charger and that this post has nothing to do with your factory installed inverter? I recall you have the same 2000W WFCO inverter that I do in an RP-192. I assume the factory used the same 5ft long 2-0awg cables in yours as in mine?
I don't know the answer to that question. My power box is in the rear "I have a rear kitchen" and the battery is in the front normal location. I can see the red wire going to the battery cut off which looks to be 8awg. I am not sure the exact gauge as I can't read what is printed on it because of location but I will be able to see all that when it gets a little warmer and I switch out the batteries. The battery has a second very large wire (or harness) that disappears under the enclosed chasse. I may be getting confused if the battery cut off only removes the 12 volt accessories and that is why the wire is that small. I do have the same 2000W WFCO so I'm sure R-POD set up to be safe and the trailer is supposed to be lithium ready.
wlfclf2000 is offline   Reply With Quote
Old 03-01-2024, 11:24 AM   #20
Member
 
Join Date: Jul 2023
Location: Waynesville, NC
Posts: 88
Quote:
Originally Posted by wlfclf2000 View Post
I don't know the answer to that question. My power box is in the rear "I have a rear kitchen" and the battery is in the front normal location. I can see the red wire going to the battery cut off which looks to be 8awg. I am not sure the exact gauge as I can't read what is printed on it because of location but I will be able to see all that when it gets a little warmer and I switch out the batteries. The battery has a second very large wire (or harness) that disappears under the enclosed chasse. I may be getting confused if the battery cut off only removes the 12 volt accessories and that is why the wire is that small. I do have the same 2000W WFCO so I'm sure R-POD set up to be safe and the trailer is supposed to be lithium ready.
That heavy gauge cable goes to your inverter and doesn't run through the disconnect switch, nor does it go to the power distribution/converter panel. There should also be a heavy gauge black negative cable which runs directly to the inverter and not to frame ground. In an earlier thread you said your inverter is mounted in the pass through where you were going to install upgraded batteries. I assume that pass-through is at the front of the RV near the tongue...
__________________
2023 r-pod RP-192
not enough solar capacity
not enough battery capacity
not enough towing power
"Never underestimate the power of human stupidity."
-Lazarus Long
jlankford is offline   Reply With Quote
Reply

Tags
question

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Forest River, Inc. or any of its affiliates. This is an independent, unofficial site.



All times are GMT -5. The time now is 04:27 AM.