User Tag List
Results 1 to 10 of 83
-
01-13-2022, 12:45 PM #1
- Join Date
- Feb 2020
- Location
- Summer Pure Michigan, Winter Phoenix
- Posts
- 25
- Mentioned
- 2 Post(s)
- Tagged
- 0 Thread(s)
LIFeO4 Batteries and charging while towing
Question for those that have switched over to Lithium batteries in your TT or 5er.... did you install a DC to DC charger on the 12v line from your tow vehicle? If not, have you had issues with alternators burning up? About to take the plunge with lithium but having second thoughts whether all of the hassle changing over convertors, DC to DC chargers.....
https://www.victronenergy.com/blog/2...rging-lithium/
-
01-13-2022, 01:55 PM #2
- Join Date
- Jul 2014
- Location
- Wherever...
- Posts
- 9,010
- Mentioned
- 187 Post(s)
- Tagged
- 0 Thread(s)
We have BB LiFePO4 batteries and did not install a DC-to-DC charger in the truck. We've had zero problems with this setup. The batteries will only take what your alternator(s) will send them (they do not "draw" from a charge source) - and over pretty small wire. We have 300 watts of solar that keep the batteries charged (and the residential fridge running) while on the road.
RobU.S. Army Retired
2012 F350 DRW CC LB Lariat PS 6.7
2020 Solitude 310GK-R, MORryde IS, disc brakes,
Sailun LRG tires, solar, DP windows, W/D
(Previously in a Reflection 337RLS)
Full time since 08/2015
-
01-13-2022, 02:23 PM #3
- Join Date
- Feb 2019
- Location
- "Murvul", TN
- Posts
- 3,354
- Mentioned
- 135 Post(s)
- Tagged
- 0 Thread(s)
There are several factors to consider with that question. Alternator size, wiring size and ampacity for the wire that goes back to feed the DC to DC charger, how large or small your battery bank is in AH, as well as the SOC in the batteries when you get ready to drive away with the camper. Also, how much load is going to be pulled on the 12V side of things while you are traveling.....do you have a large inverter, or maybe a 12VDC refrigerator that is the compressor type? There are way too many variables until the unknowns are known.
This spring sometime, I plan on having the Norcold in mine switched over to a pair of 12VDC compressors to operate it when traveling (not worried about it when plugged into shore power) and I also am in the process of building a 304 AH LFP battery from 4 raw cells. I also do not plan on running a DC to DC charger, at least initially, and I also do not plan on swapping the OEM converter to a LiFePO4 converter.Last edited by xrated; 01-13-2022 at 02:27 PM.
2016 F350 CrewCab Dually
2018 Momentum 394M...Heavily Modded!
2023 Suzuki GSX-S1000 GT+
Excessive Payload is a Wonderful Thing
"If it ain't fast....It ain't Fun"
-
01-13-2022, 02:24 PM #4
- Join Date
- Apr 2017
- Posts
- 1,090
- Mentioned
- 15 Post(s)
- Tagged
- 0 Thread(s)
-
01-13-2022, 02:38 PM #5
- Join Date
- Apr 2017
- Posts
- 1,090
- Mentioned
- 15 Post(s)
- Tagged
- 0 Thread(s)
If he doesn't change the stock charging system he will not burn up an alternator regardless of those other variables.
In my case the truck supplies about 7 amps +/-. which mostly offsets the residential fridge draw. I'll lose about 15-20 amps off the batteries in a long pull day(10 hrs+). I do not run a DC to DC charger. I see no reason to unless you want to use the TV as a real charging source.
You can just drop in lithium's and nothing else but IMO changing the converter is optimal and pretty easy. A monitoring system is also a good idea but not a requirement. Its also pretty easy to do2021 Solitude 375 RES-R
2024 GMC Denali ultimate DRW
-
01-13-2022, 05:23 PM #6
- Join Date
- Feb 2019
- Location
- "Murvul", TN
- Posts
- 3,354
- Mentioned
- 135 Post(s)
- Tagged
- 0 Thread(s)
As I stated, my initial plan is to use the WFCO 9855 Converer/Charger that came with the Momentum. It will bulk charge at 14.4 volts for up to 4 hrs if needed. After that, it drops down to 13.6 volts in absorption mode. The should charge the battery quite well while on shore power. The refrigerator, with the JC Refrigeration conversion should pull about 10.8 amps. And even if the compressor ran the entire time, that would only be about 130 A.H.s for a 12 hour day on the road.
I personally will never do a 12 hours day on the road, and I'm sure the fridge isn't going to run continuously....so I should be good for what I want the battery to provide. The battery that I'm building will have a Smart BMS and I'll see if the Bluetooth part of it is sufficient for monitoring SOC and other battery parameters. If I'm not happy with it's ability, I will likely get a Victron 712 to help out with monitoring of the system.
As far as burning up the alternator, you're probably correct in it not happening with the stock truck wiring. I think the fuse for that circuit would likely blow long before the alternator went south or up in a puff of smoke. To me, the only way I would use a DC to DC charger is if I ran a dedicated line for it...not the line that is in the 7 pin bundle. To me, that would be kind of like trying to fill a swimming pool with a garden hose.....possible, but not practical.Last edited by xrated; 01-13-2022 at 05:29 PM.
2016 F350 CrewCab Dually
2018 Momentum 394M...Heavily Modded!
2023 Suzuki GSX-S1000 GT+
Excessive Payload is a Wonderful Thing
"If it ain't fast....It ain't Fun"
-
01-14-2022, 02:41 AM #7
Does your WFCO actually charge in Bulk mode?
None of mine have. And most everyone else that has checked report the same. They seem to be stuck at 13.6..... And that is with LA batteries.
With Lithiums maintaining a hiigher voltage thru out their charge level, any stock converter will not go into bulk very easy, if at all.
I have seen many people report on this. One wes as low as (IIRC) 52% being the best his stock converter would do with Lithiums.2021 398M Full Body Paint 8k axles. LRH tires. Disc brakes.
Two bathrooms, no waiting 155 fresh, 104 black, 104 grey 1860 watts solar.
800AH BattleBorn Batteries No campgrounds 100% boondocking
2020 Silverado High Country 3500 dually crewcab Duramax Allison
-
01-14-2022, 03:59 AM #8
- Join Date
- Feb 2019
- Location
- "Murvul", TN
- Posts
- 3,354
- Mentioned
- 135 Post(s)
- Tagged
- 0 Thread(s)
To be honest, I have not checked it for the 14.4 Volt output, probably something I need to do though. Even if it doesn't go into bulk charge voltage, the absorption mode voltage of 13.6 is high enough, if left there at that voltage level, to charge the LFP battery to right at 100% SOC, based on battery charts I have seen. I plan on doing my initial charge on the new battery and using an ISDT Q8 charger/balancer. When the charger senses any one of the cell's voltage to be at 3.6 volts, charging will stop and the Q8 will then start doing an active balance of the cells. Once that is reached, the cycle is done and all four cells should be at 100% or very, very close to that. I am then going to try and do a capacity test on the battery, monitoring it with the BMS and setting the cutoff voltage level to 2.6V/per cell......or 10.4 volts for the battery. Once that is done, the battery will be charged back up and individual cells checked for proper balancing.
2016 F350 CrewCab Dually
2018 Momentum 394M...Heavily Modded!
2023 Suzuki GSX-S1000 GT+
Excessive Payload is a Wonderful Thing
"If it ain't fast....It ain't Fun"
-
01-14-2022, 06:52 AM #92021 398M Full Body Paint 8k axles. LRH tires. Disc brakes.
Two bathrooms, no waiting 155 fresh, 104 black, 104 grey 1860 watts solar.
800AH BattleBorn Batteries No campgrounds 100% boondocking
2020 Silverado High Country 3500 dually crewcab Duramax Allison
-
01-14-2022, 07:12 AM #10
- Join Date
- Feb 2019
- Location
- "Murvul", TN
- Posts
- 3,354
- Mentioned
- 135 Post(s)
- Tagged
- 0 Thread(s)
I'll be more than happy to share the results, when it finally happens. I just today, got notice that the battery cells I have ordered have a UPS tracking number and are supposed to arrive tomorrow. I've pretty much assembled all the parts that I need and built a heated battery box (not quite done with it) with a temperature controller, as well as a 200A Smart BMS....so things are finally beginning to move forward, as long as the battery cells are not damaged and are in great shape when they arrive. I'm guessing that it will be several weeks before everything comes together fully for me to be able to put up my results......charging, top balancing, testing the heated box and well or not it performs, doing a capacity test, etc, etc. It's been quite a journey so far, and all of this started in Oct. last year. LOL!
2016 F350 CrewCab Dually
2018 Momentum 394M...Heavily Modded!
2023 Suzuki GSX-S1000 GT+
Excessive Payload is a Wonderful Thing
"If it ain't fast....It ain't Fun"
25G fresh water capacity?
Today, 05:22 AM in General Discussion