 |
|
12-28-2024, 11:29 PM
|
#1
|
Junior Member
Join Date: Jan 2023
Location: San Diego CA
Posts: 26
|
LiFePo4 install on 1999 Seaview
I just finished a battery upgrade on my 1999 Seaview. I installed 2 WattCycle 100 Ah batteries, Renogy 40A DC to DC charger and AiLi shunt.
I put 250A switch breakers on each battery, and 60A switch breakers on the DC DC charger in and output.
Shunt - https://www.amazon.com/dp/B07FGFFHC6...sin_title&th=1
Batteries - https://www.amazon.com/dp/B0CLTZMP57...sin_title&th=1
Breakers - https://www.amazon.com/dp/B0DHCCR4HK...sin_title&th=1
DC to DC - https://www.amazon.com/dp/B0D78W7CSV...sin_title&th=1
I had to disable the magnetic relay that connects the batteries when charging, I did this by removing the 2 small wires behind the J1 relay, and then moved the charging cable to the starting battery. The DC to DC connects to the starting battery. I will fix the emergency start capability later by adding a new relay to momentarily connect the batteries.
Going dry camping for a week and will check out the capacity of these batteries. We use the genny for the air fryer and microwave, otherwise we use the batteries for the heat, lights (LED), and 2 CPAPs.
My old batteries were 2 6 volt Trojan 105's, I hope these 2 batteries are significantly better.
|
|
|
 |
Join the #1 RV Forum Today - It's Totally Free!
iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!
You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!
|
12-28-2024, 11:51 PM
|
#2
|
Senior Member
Join Date: Apr 2024
Location: WI Driftlesser
Posts: 2,547
|
Are you going to be driving enough to recharge? or use the generator through an inverter charger? or solar?
|
|
|
12-29-2024, 03:49 AM
|
#3
|
Senior Member
Join Date: Jul 2014
Posts: 37,088
|
A 250 amp circuit breaker is a bit overkill on a 100 amp max output battery.
|
|
|
01-01-2025, 07:22 PM
|
#4
|
Junior Member
Join Date: Jan 2023
Location: San Diego CA
Posts: 26
|
Just got back from dry camping for 4 days and most everything worked great.
Biggest issue is the Renogy DC-DC does not properly stop drawing power from the starting battery when I stop the engine, or turn off the battery charger. Manual says it will stop drawing power when the starter battery voltage is 12.6 or less, but it never stops even when the battery is less than 12V. I let it go for about 30 minutes and it never stopped. I had to disconnect it from the starter battery (from the switch/breaker) to get it to stop. When I reconnected it, it worked fine again. I will contact Renogy as its connected exactly as they recommend.
The 2 batteries went from ~100% to 60% from running 2 CPAPs and the motorhome heat all night. It was about 4- degrees at night so the heat was on quite a bit. That would have got my lead acids very low.
I have several ways to recharge, one is the MH alternator, second is the big genny, and last is my 2K Honda. I will be adding 2 solar panels in the next 30 days and that will easily bring the batteries to 100% at the end of the day, as long as there is decent sun. Otherwise I'll run the Honda 2K, or the big genny as needed.
The Renogy DC DC is the only let down so far. My motorhome is a relic, so no smart alternator. I tried playing with the smart alternator wire to see if it had any effect on stopping the draw from the starter battery when I shut the engine off, I tried grounding it, putting it to 12V but it had zero effect. I think the unit is defective, but I will send Renogy a message to see if they have an idea. Otherwise it's going back to Amazon for a replacement.
Note: I used a 250 A breaker because I want to be able to start the generator or the MH engine from these batteries in the event of an emergency where the starter battery is dead.
|
|
|
01-02-2025, 08:34 AM
|
#5
|
Senior Member
Join Date: Mar 2022
Posts: 512
|
Does the Renogy have the D+ ignition wire connected to the starter battery or to a switched 12V source?
__________________
2019 Palomino Solaire 147X
2013 Ford F150
|
|
|
01-02-2025, 03:13 PM
|
#6
|
Junior Member
Join Date: Jan 2023
Location: San Diego CA
Posts: 26
|
Quote:
Originally Posted by TacomaJoe
Does the Renogy have the D+ ignition wire connected to the starter battery or to a switched 12V source?
|
This is a newer model from Renogy, it has Alt+ and ground on the input side, and Battery + & - on the output. The Alt+ is connected to the Starter battery + which is connected to the alternator. So it is connected to the starter battery, not a switched 12V source.
This DC DC is different from the blue box Renogy was making. I can't find any Youtube videos on it, and it seems it's not reviewed on the internet yet.
|
|
|
01-02-2025, 03:37 PM
|
#7
|
Senior Member
Join Date: Mar 2024
Location: Bohemia NY
Posts: 1,976
|
You maybe made this harder than necessary
You had a battery system that was working. Even though you replaced lead acid with Lithium base, since you did not increase the A/H capacity the system for National RV would work with one slight glitch. As they used an automatic charger control relay (ACR) based on voltage from either battery bank, (how they achieved chassis battery charging on shore or generator power), the higher resting voltage of full charged lithium will keep the batters combined even after charging stops. Not the worst thing but it is a change.
To further simplify I would have used a single battery solution. Something like this.
https://www.amazon.com/Litime-LiFePO...mr_ca_hp_atf_d
On a 14.2 volt alternator, relay system peak draw will be ~60-65 amps. Going lower as state of charge increases. I install these on Vanagons with 90 amp alternators. You should have a 160? When fully charged this battery actually turns charging off so no further controls are needed.
The batteries you are using may work the same way. Do you have any monitoring so you can watch them work and manage them?
__________________
Dennis
Bohemia NY
2008 Nimbus 342 SE Carlyle
|
|
|
01-02-2025, 04:31 PM
|
#8
|
Junior Member
Join Date: Jan 2023
Location: San Diego CA
Posts: 26
|
Spoke with Renogy today and they believe the charger is faulty, so back to Amazon for a replacement.
|
|
|
01-02-2025, 09:17 PM
|
#9
|
Junior Member
Join Date: Jan 2023
Location: San Diego CA
Posts: 26
|
Quote:
Originally Posted by d23haynes57
You had a battery system that was working. Even though you replaced lead acid with Lithium base, since you did not increase the A/H capacity the system for National RV would work with one slight glitch. As they used an automatic charger control relay (ACR) based on voltage from either battery bank, (how they achieved chassis battery charging on shore or generator power), the higher resting voltage of full charged lithium will keep the batters combined even after charging stops. Not the worst thing but it is a change.
To further simplify I would have used a single battery solution. Something like this.
https://www.amazon.com/Litime-LiFePO...mr_ca_hp_atf_d
On a 14.2 volt alternator, relay system peak draw will be ~60-65 amps. Going lower as state of charge increases. I install these on Vanagons with 90 amp alternators. You should have a 160? When fully charged this battery actually turns charging off so no further controls are needed.
The batteries you are using may work the same way. Do you have any monitoring so you can watch them work and manage them?
|
Hi, if you go back and re-read my original post you'll see that I disabled what you called the ACR relay, and I also posted the shunt and battery monitoring gauge I am using.
My motorhome has room for 3 group 24 batteries under the step, I cannot fit a longer battery. I am curious on what the difference between 200Ah of batteries in a single vs doubles would be. The single battery seems more expensive.
|
|
|
01-02-2025, 10:54 PM
|
#10
|
Senior Member
Join Date: Mar 2024
Location: Bohemia NY
Posts: 1,976
|
The single battery would have made a cleaner installation and made for a single BMS. Also 230 A/H compared to the 200 A/H total. You would still be limited to 200 Amp with the BMS for an up to 2,000 watt inverter and starting the generator. As you have room for a 3rd 100 A/H battery that is also an option. You may have had room for a single 300 A/H.
My suggestion for now is stay with the 2, 100 A/H and restore the original ACR relay and forget the DC to DC Charger. Adding a 3rd battery will require the DC-to DC charger or upgrading the alternator. You will then want 60A Dc to DC.
__________________
Dennis
Bohemia NY
2008 Nimbus 342 SE Carlyle
|
|
|
01-07-2025, 10:44 PM
|
#11
|
Member
National RV Owners Club
Join Date: Nov 2013
Location: Free Range Human
Posts: 42
|
Good Job. I replaced the 2 GC-2 golf cart batteries on my 99 Tropical with 8 individual 280ah LiFePo-4 prismatic cells in a 20, 4s configuration for 560ah at 12v. They fit perfectly in the space where my old lead acid batteries were located with the 330 Heltec BMS I got to start my generator fitting in the space between the 2, 6v batteries I made. It is much cheaper to build your own batteries than to buy pre-made ones plus I could have only fit 2, 100ah batteries in this space that I now have 560ah in.
I cut a 1" hole in my step riser and put a 1" computer CPU fan in this space to keep the battery compartment at room temperature to prevent the BMS from shutting down charging from getting too cold and the battery life being shortened in the summer from getting too hot. I built a 620w liftable solar array on the side of my coach, mounted over my bedroom window. It makes a nice window awning and charges my battery just fine. I also bought a Renogy B to B charger but don't use it. The hardest part of the project was disconnecting that relay behind the fuse panel.
I mounted the array on the side to keep the roof free for my large 4,400w solar array that charges a 320ah 48v battery I have under the bed.
__________________
"There is no worse tyranny than to force a man to pay for what he does not want merely because you think it would be good for him." – Robert Heinlein
|
|
|
01-07-2025, 10:50 PM
|
#12
|
Junior Member
Join Date: Jan 2023
Location: San Diego CA
Posts: 26
|
Quote:
Originally Posted by sushidogchip
Good Job. I replaced the 2 GC-2 golf cart batteries on my 99 Tropical with 8 individual 280ah LiFePo-4 prismatic cells in a 20, 4s configuration for 560ah at 12v. They fit perfectly in the space where my old lead acid batteries were located with the 330 Heltec BMS I got to start my generator fitting in the space between the 2, 6v batteries I made. It is much cheaper to build your own batteries than to buy pre-made ones plus I could have only fit 2, 100ah batteries in this space that I now have 560ah in.
I cut a 1" hole in my step riser and put a 1" computer CPU fan in this space to keep the battery compartment at room temperature to prevent the BMS from shutting down charging from getting too cold and the battery life being shortened in the summer from getting too hot. I built a 620w liftable solar array on the side of my coach, mounted over my bedroom window. It makes a nice window awning and charges my battery just fine. I also bought a Renogy B to B charger but don't use it. The hardest part of the project was disconnecting that relay behind the fuse panel.
I mounted the array on the side to keep the roof free for my large 4,400w solar array that charges a 320ah 48v battery I have under the bed.
|
Wow you have tucked a lot of power into that motorhome!
How about a pic of that array you hang over the bedroom window?
|
|
|
01-08-2025, 09:52 AM
|
#13
|
Member
National RV Owners Club
Join Date: Nov 2013
Location: Free Range Human
Posts: 42
|
I'll be happy to e-mail you some pics of my set-up. Just send me your E-mail address. Mine is Sushidog@earthlink.net.
__________________
"There is no worse tyranny than to force a man to pay for what he does not want merely because you think it would be good for him." – Robert Heinlein
|
|
|
01-12-2025, 02:46 PM
|
#14
|
Junior Member
Join Date: Jan 2023
Location: San Diego CA
Posts: 26
|
I've been doing more reading and have decided to stay away from Renogy. I know lots of people have good luck with Renogy, but when I compare the documentation and flexibility of Victron I think the higher cost is worth it. I have read very few negative posts on Victron that were not user error.
So, I bought a 30A Victron DC/DC and a Victron 100/30A MPPT Solar charger.
I have a few scenarios on how I use my RV currently, one is dry camping for a week while we go off roading, one will be a road trip of 1-2 months with various types of camping, and the rest are full hookups.
I do the 1 week dry camping trips 90% of the RV use, so that was my primary focus. I usually fully charge up at home, so I don't need rapid charging for that. We don't usually use/need much power out camping, just charging phones, CPAPs, lights, and the furnace at night. Last trip out I figured I used ~40% of the battery capacity each day, so ~80Ah. If I add 50% (fudge factor) to that I need to recover 120Ah each day. Figure 6 hrs of daylight means I need ~20A charge rate. 14.67 * 20A = ~300Watt panel. I will most likely shoot for 500W in 2 panels, so 250-300W each to cover inefficiency and to catch up if I have hazy days. Going to wire the 2 panels in series.
I can always use my 2000W Honda or the RV genny if I fall too far behind.
I don't have solar panels yet, but will be getting to that in the next few weeks. Next will be researching the mounting, I like the plastic mounts I've seen that were glued and screwed down. Will run the wires down the refridgerator exhaust pipe.
|
|
|
 |
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
» Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|
|
|