This forum has been very helpful and informative for me both with Lithium Iron (LiFePO4) batteries as well as the trickle charging of the starter battery. After reading various threads and additional research from other forums, manufacturer sites, talking with Winnebago directly and reviewing Winnebago wiring schematics on the Winnebago Owners page, I wanted to contribute what I learned and the work I have completed for the benefit of others that may also pursue aftermarket/after purchase LiFePO4 battery options. BTW, I believe either AGM/Lithium Iron is a must for boondocking any length of time with coaches utilizing a compressor fridge which is not nearly as efficient as propane IMO and as stated in threads on this forum.
A inventory review of what the 2020-21 Navion/View has without the Winnebago Xantrex Lithium battery upgrade:
1) Xantrex Freedom XC 2000 Watt Inverter/Charger (part number 817-2080)
even though the control panel inside the coach only indicates that this is just an inverter (“Freedom X” as printed on the remote controller inside the coach vs “Freedom XC” printed on the inverter controller),
2) ChargeMatePro 40 under the pax seat limiting the max amperage from the chassis alternator to just 40A,
3) Zamp Solar Charge Controller (ZS-30A) above the fridge,
4) Onan Generator (LP or Diesel, doesn't matter, but I have the Diesel version),
5) Shorepower, and
6) 2 Flooded Deep Cycle Napa batteries, the only item that needs to be removed and replaced with LiFePO4 batteries. Battery cables may be needed depending on the pole configuration of the new batteries. I confirmed no other hardware or upgrades were required with Winnebago directly as well as the dealer RV tech lead (Trans West).
The standard flooded batteries can be charged from one of four sources, 1) Solar via the Zamp Solar Charge Controller, 2) Onan Generator by way of the Zantrex Inverter, 3) Shorepower by way of the Zantrex Inverter, and 4) from the chassis alternator by way of the ChargeMatePro 40. The new LiFePO4 batteries will be charged from the same source.
Upgrading from the flooded deep cycle standard house batteries to LiFePO4 requires consideration of the charge source amperage and voltage, referencing the sources above, controlled by three devices;
1) Zamp Solar Charge Controller,
2) ChargeMatePro 40, and
3) Zantrex Freedom XC 2000.
Changing the Zamp Solar Charge Controller (solar power source) from default AGM value to liFePO4 automatically adjusts absorption voltage with no other changes needed (
https://static1.squarespace.com/stat...UserManual.pdf). For charge coming thru the Xantrex Freedom XC 2000 (pulling from either shore or generator power), changing the battery type on the controller adjusts the amperage and voltage based on the battery type selected with additional options to fine tune the adjustments for bulk, float, absorption, charge amps and volts, depending on lithium battery specifications from the batteries installed, Inverter/Charger manual here (
Xantrex | Power Inverter, Inverter Charger, Battery Charger Manufacturer XC/Freedom XC Series INV-CHG Owners Guide (975-0784-01-01_Rev-B)_ENG.pdf). For charge coming from the chassis alternator, there are no adjustments available on the ChargeMatePro 40; yet the ChargeMatePro 40 protects the house batteries from amperages beyond 40a which helps prevent damage to the house batteries.
Netting out the above, if you purchased the 2020/21 Navion/View with the standard flooded deep cycle house batteries and you want to upgrade to AGM or LiFePO4, all you need to do is drop in the LiFePO4 batteries (may require wire upgrade depending on battery pole configuration) and then change the settings on both the Zantrex Inverter Charger control panel and the Zamp Charge Controller, and done. $1500-$2000 option plus about 2 hours work with basic tools versus the cost of the Winnebago upgrade referenced above, ~$5300 (I honestly didn’t even know that option existed when I bought my Navion).
Here is what I chose and installed:
Although I own the Battle Born 100AH battery ($950) and swear by these things after much abuse and punishment, I opted to try Lion 1300 105AH batteries ($1400 at Costco for two, $750 individually) principally for the cost, but also for the smaller size and a bit lighter (24lbs vs 31lbs times two batteries). I also chose the LiFePO4 over AGM due to total cost of ownership over a longer period of time, I believe it is more economical to go the LiFePO4 route, as well as the difference in weight given the limited Cargo Carrying Capacity (CCC) I inherited with the coach, 1288lbs according to the sticker inside the pax door.
WRT to the Lion 1300, most of the youtube reviews I watched for the newer 1300 model seemed generally favorable. If the spread in price between the Lion 1300 and BB was less than $150 each and the BBs were more readily availability, I would have opted for the BB again. Note that the Lions are manufactured and assembled in China while the Battle Born batteries are assembled in the US and are UL Listed. Here is the link to the Lion 1300 battery specs,
https://support.lionenergy.com/files...l_20191209.pdf Here is a link to BB battery specs,
https://battlebornbatteries.com/shop...cycle-battery/
Additionally, I installed the AMP-L-Start from LSL products (
AMP-L-START Starting Battery Charger/Maintainer - Overview Page) choosing this option over the TRK-L-Start because of the ability to adjust the start and stop charge for Lithium house batteries by way of a jumper connection. This install was fairly simple, less than an hour of time. I removed the pax seat and the bracket that allows the seat to rotate (8 bolts) to access the ChargeMate Pro 40. The top pole of the ChargeMatePro connects to the “Starting+” stud on the Amp-L, the bottom pole of the ChargeMatePro connects to the “House+” stud on the Amp-L, and the “GND-“ connected to the large front right bolt inside the seat pedestal, all using the supplied ring terminals but requiring separately purchased 10 gauge wire with each wire about 12” long based on where I mounted the Amp-L on the right rear outside of the pax pedestal near the B pillar, easily accessible by lifting the chair pedestal skirt. I adjusted the jumper as recommended by LSL to the lithium setting after confirming this was correct via email from the lead engineer at LSL.
Additional resources:
Navion/View 24J Chassis Wiring Diagram,
https://www.winnebagoind.com/diagram/2020/000164549.pdf
ChargeMatePro 40 specs,
https://www.mastervolt.com/products/...e-mate-pro-40/
Please let me know if I left anything out, any information is inaccurate, or if you have any additional questions.