Electrical Setup 101 Assistance - Solar and Vehicle Dual Charging for LiFePo4 Power Station (1 Viewer)

[HSTexan]

I have and will always maintain that electrical is my weakest point of vehicle setup. I've decided this winter I want to finally bite the bullet and get my electrical setup the way I want/need. I have a hard time justifying the weight of a full time dual battery setup, so the solution I'm currently using is a removable Bluetti 180T LiFePo4 1433Wh power station plugged into the DC socket on the vehicle and then removed at base camp and hooked up to a 200W solar panel. I would like to simplify this setup so that it can stay in the vehicle full time and charge off both solar and vehicle and additionally increase the wattage to speed up the charging process. As it stands right now it can only take in about 90W while driving through the DC socket and 160-170W max from the panel depending on sun. Given the size of the power station it can take a considerable time to get it topped back off and my last two trips have really pushed the limit and comfort of how close it got to draining completely and letting my fridge die. I'd like to maximize charging capability while minimizing fuss and making sure the starter battery is always protected from draining too low.

There are a couple of options I've considered:

Setup 1: Vehicle battery --> Bluetti Charger 1 (this is an alternator charger that takes excess power generated for charging purposes; up to 550W output) --> Bluetti Power Station

Additionally I'd have roof solar --> XT60 connector in vehicle

Setup 1 would let me swap back and forth between charging the power station from the car and solar, but would require me to manually switch the cable every time I go from parked to driving. I've also read that the Charger 1 has quite a bit of room for improvement as far as use and battery protection goes (timeout is 30 min after shutoff, requires manually turning on and off)


Setup 2 is an attempt to merge these so I don't need to swap cables:

Vehicle Battery & Roof Solar --> Redarc BCDC1225 --> Custom made XT60 with power lead from Redarc and ground to chassis (or run to back to vehicle battery/Redarc ground)

XT60 would just say in cargo area unplugged when not in use


Questions for setup:
1. Is there an XT60 switch that would allow me to toggle which input is active without needing to manually unplug and replug in a cable? This would be a simple solution for Setup 1 so it didn't require me to do anything with the cables, but rather toggle a switch when necessary.
2. Is it possible to do what I'm thinking of with splicing together an XT60 from the Redarc power lead and chassis ground or would that be ill advised?
3. Looks like the BCDC1225 tops out at 375W out; the powerstation can handle up to 500W in through the DC/XT60 connection. Could I get away with the BCDC1240 instead since it has a max output at 600W? That way the Redarc doesn't become the limiting factor and allows the power station to charge at max capability. Between 200-250W of solar plus charging from battery I feel like it would not be difficult to surpass the 375W cap
4. Is there an easier way to accomplish what I'd like that I haven't even thought about or know about?

 

[HSTexan]

So follow up to this; I emailed Redarc proposing what I had in mind and they believed given two independent management systems that the Redarc would not output as it wouldn't see a battery feed. It truly is meant to only connect to a dedicated two post battery, be it LiFePo4, lead acid, AGM, or lithium.

I then proposed the question to the Bluetti group on Facebook as well and someone forwarded essentially the exact product I was hoping existed. Another new solar/power startup that was created on Kickstarter called ETaker. They have a 1000W DC-DC charger that can pull up to 500W from the vehicle and 500W of solar. The beauty of they system is that it comes with the vehicle input cable with ring terminals on one end leading to an XT90 input on their charger box. The solar input is an XT60 (which I already have), and it comes with an output cable that is XT60 already--a perfectly ideal product that will require no splicing on my end. The downside is I'll now have to run two pairs of wires through the firewall grommets, but still much better than needing to manually swap cables out. Listed at $300 on their website, but $230 on their Amazon store--it's also about half the price of a BCDC. Put it on order and will be testing it out before running wires, just to make sure it works as expected, but seems to be the perfect solution.

Amazon Link

 

[jjtrou2072]

I went down a similar road with my Bluetti AC 200P last summer trying to figure out the best way to charge the bank on trips.
I have portable solar panels but find my style of camping isn't that great for solar charging. (Under Tree Canopy / Not usually staying in one place for long)

I wanted something that would charge relatively quickly while driving. So I just kept it simple and wired in a 120Volt AC inverter in the rear. I use the AC charging brick when I'm driving which pumps in 500watts. I don't think I would want to pull much more than 500 watts from the stock alternator.

It's a simple solution with the added benefit of having some AC outlets accessible in the rear (while car is running) with or without the battery bank.

Just my .02

 

[tbisaacs]

I had two generations of Goal Zero And ultimately decided the occasional portability of them wasn’t worth trading off vehicle integration. For a permanent build like you truck, dedicated lithium is the only way to go IMO

 

[mfeferman]

I used a victron dc-2-dc boost converter. I pulled a 4 gauge wire from front to back. It charges my LiFePo4 solar power station.

 

[FrazzledHunter]

Hopefully by now it's clear that off-grid camping is eminently do-able.

If you're considering portable solar panels I suggest you have a look at Merlin. The review linked below mentioned some things about Merlin's quality and performance that made me buy their XP-170. I'm happy to report I am very happy with the panels. They're extremely light, durable and uniquely actually deliver their stated wattage or darned close. They make all kinds of panels for permanent mount for vehicles.

I actually bought the panels from a company called 4thD Solar.

Interestingly, 4thD Solar is owned by the same guy that imports Kimberly Caravans to the US who I met at Overland East 2023 but I didn't know this when I bought the panels. It was when we were looking at travel trailers that I noticed all the Merlin portable panels. I talked to the owner for a long time regarding off grid implementations, solar panels, charging from the tow vehicle, the RV industry and other topics. I found him to be an extremely interesting and knowledgeable person. Kimberly also uses Merlin for their factory supplied solar panels on their caravans AFAIK.

I have no affiliation with either Merlin, 4thDSolar or KImberly nor do I receive anything for mentioning & plugging their products.

REF:
Solar panel test results
Portable Solar Panel Testing- Results - https://forum.expeditionportal.com/threads/portable-solar-panel-testing-results.200834/

4thDSolar
Real Solar Power! The best, most efficient and toughest solar panels - https://4thdsolar.com/

EDIT: link to Merlin Solar
Home | Merlin Solar - https://www.merlinsolar.com/

Kimberly Caravans booth with Merlin XP-170 Solar panels at Overland East 10/2023

Our Merlin XP-170 in heavy use at Oregon Inlet Campground 6/2024:

 

[HSTexan]

Lot of good info in here and appreciate the input-- @tbisaacs man I went back and forth so much on a permanent LiFePo4 battery in the cargo area, but I just don't think I have a great place to mount one permanently. The more I think about it the more I think I'll end up there one day, but for now this ETaker is going to get a chance. It should be here today for me to test out before permanently wiring it up. If it doesn't work like I hope I've already pulled my drawers out in prep to run wiring so it would be an easy pivot. Would just need to fab up some sort of battery tray--probably between drawers and backseat.

 

[FrazzledHunter]

The ETaker is new to me and looks interesting. The wattage is pretty high. Is the input wattage selectable?

The block diagram below is what I've done so far to support camping in general. The refrigerator can run off either the Goal Zero or the Odyssey battery under the hood. The SB-175 is used to charge our trailer under tow.

 

[HSTexan]

The ETaker is new to me and looks interesting. The wattage is pretty high. Is the input wattage selectable?

The block diagram below is what I've done so far to support camping in general. The refrigerator can run off either the Goal Zero or the Odyssey battery under the hood. The SB-175 is used to charge our trailer under tow.
View attachment 3758485

It is 1000W combined split vetween 500W max from vehicle and 500W max through solar. That said it does have basic selectability to limit the pull from vehicle to either 300W, 400W, or 500W. My current plan is to pair it with a 300W solar panel and leave it set to the lowest setting of 300W. This should hopefully give me somewhere around 250W in (in ideal conditions) when the vehicle is powered off from solar alone and then hit the max of 500W combined when driving while also keeping the vehicle draw as low as possible.

 

[FrazzledHunter]

It is 1000W combined split vetween 500W max from vehicle and 500W max through solar. That said it does have basic selectability to limit the pull from vehicle to either 300W, 400W, or 500W. My current plan is to pair it with a 300W solar panel and leave it set to the lowest setting of 300W. This should hopefully give me somewhere around 250W in (in ideal conditions) when the vehicle is powered off from solar alone and then hit the max of 500W combined when driving while also keeping the vehicle draw as low as possible.

500W/40A off your OEM alternator as input to your would be the most I would draw off the OEM alternator. Prior to my alternator upgrade I drew 40A to feed my Victron 12|24-15 which output 360+W-30A (15A @24V) to my Goal Zero 1500X. The point is, these chargers aren't 100% efficient so whatever the output, the input will be more. It's wise to measure it all with a power meter.

The OEM alternator is rated at 180A however, I really don't know if I was taxing my alternator or not as that 180A is the maximum at some unknown engine RPM. I didn't run it very long at that load, maybe a year and not continuously. My LC200 engine idles as low as 550RPM which at that rate, I am assuming, the alternator produces about 100A. In addition, the alternator cooling fan is not cooling as much. If the Amp guess at 550 RPM is close to true then drawing +40A to your charger is a lot. I haven't seen a RPM/Power curve for the OEM alternator. If anyone has one I'd love to see it as I think it would settle a lot of discussions.