48v li ion conversion plus solar

[[email protected]]

I am in the process of replacing the factory installed 12v battery with a 48v Li ion battery. I am wondering if anyone has done this and would be willing to share their experience? I have a 2023 vista cruiser TT (19 CSK). I plan to install a 48v to 12v step down converter to keep the lights, etc on 12v and use the 50 AH 48v (2400 watts) battery power through an inverter/controller/charger to power things like a coffee maker, cpap, microwave, tv, etc. I will have all the parts next week including a 410w solar panel.

[socalfrog]

Did a 24V to 12V LiFeP04 conversion and some of my lessons will likely be applicable to your conversion.
My system is 8 EVE 3.2V 280AH batteries in series.
All of my electronics are Victron, pricey but worth it IMO. Have two 450W panels in series up top
Two issues I ran into
1. The 24v to 12v 50A converter did not have the capacity to start my generator (diesel). Had to add a second converter in series to be able to start the generator.
2. The inverter/converter specs were misleading. I ordered a 1800W inverter thinking it would be sufficient to fun my microwave and one AC (Not at the same time). Turns out the 1800w rating in for 25 degrees Celsius. Once the inverter starts working it heats up significantly to over 60 degrees Celsius and at that temperature the inverter only supplies about 1100w which is not enough. Ended up getting a 3500w inverter that has a 65degree Celsius capacity of over 1800w. Now I can run microwave and ac (again not at the same time) with no issues.

[[email protected]]

Thanks for your input. So you went from 24v to 12v? Are you talking about a step down converter to allow your 12v camper lights, etc to function properly?
Did you change your 12v camper to 24v and if so what has been your experience with battery life?

[socalfrog]

All of the original motorhome electrical is still 12V. Used a Victron 50A 24v to 12V transformer, which turns out is not enough to crank the generator. Added a second transformer in parallel to give 100A and now the generator will start. Had no idea it took so much to crank over the generator.

The new victron components are all 24V (solar charge controller, input to inverter)

[[email protected]]

It is time to mount my 410watt solar panel. I intend to be careful and use a piece of plywood under my bulky body when on the roof. Has anyone mounted a panel on the curved roof of a vista cruiser? I have a 2023 19csk and there is a perfect spot above the door forward (panel size is 45 x 68 inches). I am concerned about tape, glue, mastic or some non mechanical way of holding the panel securely. I would appreciate any advice.

[Just two]

I have mounted panel on two different fiberglass RV roofs. The first I added a rack and installed 2 100 watt panels. Recently I installed 4 - 200 watt on our BT 2510. On the recent install I started out just gluing the mounts to the roof. I did replace one and the glue was on there very well. Our build changed and we removed the ceiling which gave me access to the underside of the roof. I reinforced the mounts with screws into added blocks from below. We plan on a future trip to Alaska and don’t want to leave a panel on the side of the highway.

The glue method works, but with those larger panels I would add more mounts. I would not use only glue on a membrane roof. Also I always planned on hardware mounting the panel to the mounts.

[Just two]

We also went with a 24 volt system with 3000 watt hybrid inverter/charger plus 800 amp hour of lithium 4x12 volt 200 watt in series/parallel. We kept the 12 volt house system, replaced the lead acid with two 12 volt 105 amp lithium. We replaced the charger in the ac/dc cabinet with one that supports lithium.

Looking at adding engine charging for the 24 volts.

[[email protected]]

Thanks for your insights and good luck on your trip to Alaska! My installer (me) thinks there must be an aluminum frame that the roof is attached to and I should be able to determine the locations of cross members. I think taping down and then screwing through to the aluminum frame should provide solid attachment. I will post my results.

[Just two]

No trip yet, there’s a lot of building before that trip.

We noticed when there was a lite frost on our roof you could see the difference in the ice where the frame members are.

You may want to use some u channel on the roof to catch the trusses then mount the collectors to the u channel.