Lithium powerwall upgrade

[JoeyCharismatic]

I have recently given my TM a major upgrade. It was a project born of Covid lock-in boredom, and overkill for a rig of this nature, but I share it with you today.

I have installed a 15kWh Lifepo4 battery bank with a 3kw Victron Multiplus battery inverter. In practical terms, I can run my entire rig, including AC, for 15-20 hours with no electrical hook up, or generator running.

I may post pictures or answer questions about it here if anyone is interested.

Happy trails.

[Bill]

Wow! What a beast! That bad boy must weigh 350-400 pounds. And I won't inquire as to the price. That will be a great setup for disaster preparedness, like a hurricane in Florida.

Bill

[Kidkraz]

Yes, picture's would be great. I have a dinky solar system compared to yers.

[ShrimpBurrito]

Wow!!! Yes, more details and photos please! Would love to see this.

Dave

[JoeyCharismatic]

Wow! Glad to see the interest! It weights about 200lbs total, batteries were a steal at $1800 from China, before the supply chain issues kicked in, and another 1200 for the inverter and I'll pretend the wiring and unexpected costs weren't significant. Let me bring some pics up.

[JoeyCharismatic]

15kWh battery installed.

[rickst29]

It's awfully hard to find this Thread within 'forum admin'/'account help'/'suggestion box'.

[rickst29]

Wow! What a beast! That bad boy must weigh 350-400 pounds. And I won't inquire as to the price. That will be a great setup for disaster preparedness, like a hurricane in Florida.

Bill

The battery cells are about 16 lbs each. 16 of them makes about 260 pounds, and the Victron unit isn't terribly heavy. Although picture #2 doesn't show all of the cells, I'm assuming them to be 1P16S (One battery pack of 16 cells in series). This looks great - although, to add additional lifespan for the cells, I would have compressed them. OTOH, a compression structure would add more weight and much more cost.

The welded-on battery cell terminals are very interesting - and probably more convenient than screw-in studs. (With screw in studs, you must be VERY careful to apply the right amount of torque.) This is beautifully done!

[Tymanthius]

The battery cells are about 16 lbs each. 16 of them makes about 260 pounds, and the Victron unit isn't terribly heavy. Although picture #2 doesn't show all of the cells, I'm assuming them to be 1P16S (One battery pack of 16 cells in series). This looks great - although, to add additional lifespan for the cells, I would have compressed them. OTOH, a compression structure would add more weight and much more cost.

The welded-on battery cell terminals are very interesting - and probably more convenient than screw-in studs. (With screw in studs, you must be VERY careful to apply the right amount of torque.) This is beautifully done!

What do you mean you say 'compression structure'?

[rickst29]

The formal testing was done by EVE on their own cells, but the results are widely agreed to be applicable to any other thin-wall rectangular cells. Compression keeps the sidewalls from expanding and contracting as much. In the test, compressed cells (around 12-14 PSI) had DOUBLE the lifespan of the uncompressed cell in the test - all subjected to the same "charge/discharge/recharge/repeat" regimen. IIRC, it was roughly 5000 cycles versus about 2500. They discharged them pretty deep.

Here's a pretty good photo of the concept, in which I used 4 compression springs to push steel plates into the large "faces" of some LFP cells. The small sides , and the top/bottom, do not need to be compressed separately to achieve the benefit (and the EVE test pressed only along the "big" faces of the cells.) Although I have used steel plates on my two "smaller" batteries, most people use 3/4" plywood. Cheaper and easier to work with.

For a plywood example, see https://diysolarforum.com/threads/prismatic-cells-on-the-way-what-do-i-need.34498/post-430244

One of my own battery packs (before adding a heater pad and wood "casing") is show in the attached photo.

[JoeyCharismatic]

These pictures are not of the final install, as the victron is now mounted on the right side divider of the compartment, and cables/breakers and various add-ons are not fixed in place here. The shunt, not pictured, is currently just dangling - its a work in progress.

For compression - look close: there's a 1x6 on each end held tight by a ratchet strap. This is an ingenious way to apply compression in a very controlled manner, with evenly distributed pressure, and yet can be removed in seconds. I also am of the mind set that compression may be overrated in its need, regardless of the increase in lifespan, but I did it really well anyway.

The weight may be more than I originally stated, as I think it may be measured in kilos, I'll have to revisit it to get the actual numbers.

The Victron is amazing really, I'll post more about the full system tonight.

[Bill]

Can this please be moved to 'Electrical'? It's awfully hard to find this Thread within 'forum admin'/'account help'/'suggestion box'.Rick -

Yes, it is in the wrong place and hard to find. As you suggest, I initially moved it to Electrical, where it clearly belongs. But then Joey couldn't see it, because he does not have Sponsor status. So I had to move it back. The new Forum ownership is still wrestling with this issue. Hope to see an answer soon, since it will affect a lot of new members and new posts.

Bill

[Bill]

Wow! What a beast! That bad boy must weigh 350-400 pounds.Joey -

I think you have a 2011 2720QB, which came from the factory with 14" ST (Special Trailer) tires rated Load Range C. Have you had a chance to upgrade to Load Range D (either 14" or 15")? The original LR-C tires did not have a lot of load-bearing margin, and much as I love this project, its weight, including the panels "upstairs", eats up quite a bit of it.

Just a thought ...

Bill

[JoeyCharismatic]

As I've discovered, there is an entire portion of the site which isn't even visible to non-sponsor members. That was confusing to say the least. I may consider upgrading my membership, but I wasn't even aware it existed until now.

[ShrimpBurrito]

The original LR-C tires did not have a lot of load-bearing margin, and much as I love this project, its weight, including the panels "upstairs", eats up quite a bit of it.



That's putting it politely. The LRC tires are simply insufficient. That may be within specs on paper, but in practice, have lead to many blowouts reported on this forum. I had several alone. I'd consider moving to LRD the bare minimum, but with all the extra weight you've added, I'd consider LRE a requirement.

Good catch, Bill.

Dave

[JoeyCharismatic]

I believe I have 15" wheels with recently replaced 10 ply tires. I added the system in and removed all the existing cargo, which had to weight about the same. I don't have much issue towing it, but I recently got a weight distribution hitch, which I can't wait to try out.

[ShrimpBurrito]

Excellent. As I understand it, LRE tires are 10-ply, and when I last checked years ago, you couldn't buy them for 14" wheels. So yes, you probably do have 15" wheels.

Dave

[Agawam]

I have recently given my TM a major upgrade. It was a project born of Covid lock-in boredom, and overkill for a rig of this nature, but I share it with you today.

I have installed a 15kWh Lifepo4 battery bank with a 3kw Victron Multiplus battery inverter. In practical terms, I can run my entire rig, including AC, for 15-20 hours with no electrical hook up, or generator running.

I may post pictures or answer questions about it here if anyone is interested.

Happy trails.

I am interested in the size Trailmanor you have, the process to mount the solar panels to the roof and any advice you gained doing it. I want to install a 2nd battery and 2 solar panels (about 200 watts).

[JoeyCharismatic]

I actually haven't added to my existing 95 watt solar panel, but have plans for a 600+ watt add on in the future. If you go as large as I did with your battery, or even 5 kWh, you can usually power anything except AC/Heat/Microwave and just recharge on plug in. I will update eventually when I add in the extra solar capacity, but for now it is a battery storage solution only, though I can recharge via generator or plug in at anytime.

Speaking of generators...I finally found a micro generator that runs on propane and is powerful enough to run the AC. Champion Dual fuel 2500 'suitcase' inverter generator. I have to start the AC on low first so I don't bog it down, but once it's on its fine even on high.

[rickst29]

I am interested in the size Trailmanor you have, the process to mount the solar panels to the roof and any advice you gained doing it. I want to install a 2nd battery and 2 solar panels (about 200 watts).
Agawam, you can use https://www.trailmanorowners.com/forum/showpost.php?p=126285&postcount=1 as your index to other TM owner Solar installs. Many are of similar size to your plans.

[Wavery]

I actually haven't added to my existing 95 watt solar panel, but have plans for a 600+ watt add on in the future. If you go as large as I did with your battery, or even 5 kWh, you can usually power anything except AC/Heat/Microwave and just recharge on plug in. I will update eventually when I add in the extra solar capacity, but for now it is a battery storage solution only, though I can recharge via generator or plug in at anytime.

Speaking of generators...I finally found a micro generator that runs on propane and is powerful enough to run the AC. Champion Dual fuel 2500 'suitcase' inverter generator. I have to start the AC on low first so I don't bog it down, but once it's on its fine even on high.

I just finished insatalling our 200W solar system today (eventually may add another 200W panel).

Adding 200W to the rear roof is a peice of cake. There are panel mounting brackets that you can buy that will lift the panels about 1.5" off of the roof for cooling (they are called "z-Brackets and are available on Amazon). The bottom part of the brackets are flat and can be secured to the roof with 3M VHB (very high bond) double side tape (after a thorough cleaning with alcohol). That tape actually bonds better than screws. I have installed solar panels on 5 TrailManors and 2 Class A motorhomes using this method. Never had an issue.

If you buy CordMate II conduit (also on Amazon), you can have a very proffesional installation. These pics are of an installation that I did in 2009. I'll take some pics of my current installation later today.

I'm not sure how you would ever find room for 600W of solar panels unless you have a TM3124. Even then, it may be a struggle

[Tymanthius]

What about the flexible panels they have now? I would think you could put them on in such a way that they could even be covered when closed, thereby allowing for more wattage total.

[rickst29]

[QUOTE=Wavery;151891
I'm not sure how you would ever find room for 600W of solar panels unless you have a TM3124. Even then, it may be a struggle[/QUOTE]
I've got 480W on a 2619. 600 on a 3124 3124 would probably be easy, using both shells.

[Tymanthius]

I've got 480W on a 2619. 600 on a 3124 3124 would probably be easy, using both shells.

Which panels are those? And do they get covered when you close?

[Wavery]

I've got 480W on a 2619.

I had those flexible panels on my yacht but that was a long time ago. They lasted about 2-years and the thin little wires started parting. One cell would go dead at a time. At about 2-years, my 80W panels would max out at about 30W. I think that it was due to not being able to dissapate heat very well. I have found that the hard-framed panels last a lot longer and I would think that the camper would be cooler too.

I just like the idea of having air-flow between the solar panels and the roof.

[rickst29]

But my flex panels have worked pretty well. It may have been a matter of "dumb luck", or the fact that I've wired them in Series. Being mounted with VHB tape, they al;so have pretty good contract with the TM roof for heat dissipation.

I previously had 2x100w glass panels, and switched to flex in order to add more power while reducing weight. Since they're on the front shell, which stays fully exposed when closing the TM, they've been exposed to wind and rain during travel (as well as in-camp). Although I don't have them, I also suspect that "shingled" flex panels are pretty durable.

[Wavery]

But my flex panels have worked pretty well. they also have pretty good contract with the TM roof for heat dissipation.


Heat dissapation is the biggest reason that I stayed away from the flex panels. As you say, "good contract with the TM roof for heat dissipation" seems to mean that the TM roof would get hotter. Do you notice any heat transferring into the interior?

I have a couple more 100W glass panels to put on my TM but (like you said) the weight concern is a big issue. We're going camping soon so I'll put the panels that I have to the test. I had an 800W array on my motorhome and an 800AH battery bank. I ran a 22cu ft 110V home refrigerator. Weight wasn't an issue on that thing though.

[rickst29]

Heat dissipation is the biggest reason that I stayed away from the flex panels. As you say, "good contract with the TM roof for heat dissipation" seems to mean that the TM roof would get hotter. Do you notice any heat transferring into the interior?
Some of this heat does propagate through the ceiling, even though the 1-inch foam within the "aluminum sandwich" construction reduces the effect. When I don't have the A/C running and it's a warm day, I usually leave my MaxFan running continuously.

[rickst29]

https://www.ebay.com/itm/254698717740

They appear to be shingled and well-protected on the top, and Windy's seller ratings are extremely high.

[JoeyCharismatic]

I plan on using 360watt panels normally used on houses. It's a work in progress, but I wouldn't bet against it happening!

[Wavery]

I plan on using 360watt panels normally used on houses. It's a work in progress, but I wouldn't bet against it happening!If they are 48V panels, you could run your entire camper off of 110V AC. Just get a 48V inverter of the proper size and disonnect your TM converter. Your biggest expense may be a new set of batteries. You sure don't want to load your TM with a bunch of lead/acid batteries wired in series. I did that on my class A motorhome and ended up with about 600#s of batteries.

[rickst29]

If they are 48V panels, you could run your entire camper off of 110V AC. Just get a 48V inverter of the proper size and disonnect your TM converter. Your biggest expense may be a new set of batteries. You sure don't want to load your TM with a bunch of lead/acid batteries wired in series. I did that on my class A motorhome and ended up with about 600#s of batteries.
This quickly gets a bit more complicated than that. The biggest expense is the batteries, but the Victron MultiPlus-II 48V price is around $1300 as well.

V(mp) of most 360 watt panels is around 31-32 Volts, with V(oc) around 42 volts. The panels would need to be wired in Series to support "48v" batteries, and an MPPT solar controller would be required to handle them. Relatively few MPPT Solar controllers are built to handle "48V" batteries. Victron makes a great one, the MPPT 150/35. Add another $300 for that, or $200 for lesser machine from someone else.

16 cells of batteries like Joey's (big ones, 304Ah) now cost closer to $2400. the battery cells and another $160-200 for the BMS. Plus (maybe) additional costs, sometimes considerable, for building a 'compression' case. (I feel that to be necessary, Joey somewhat disagrees.)

After the system is done, you also need to add a 48VDC -> 12VDC "buck" converter, in order to provide power to all of the TM circuits. The Daygreen is a pretty good machine, adding another $100.
- - -
24 volts is another option.