DIY LiFePO4 battery install under ARB drawer wing (2 Viewers)

[GLTHFJ60]

I need to get some empirical data around this but I'm certainly not the first to experience the phenomena of having two charge sources somewhat cancel/limit each's ability to supply max charge current to the battery.

Typically and consistently when towing and using the Sterling BB1260 I get larger current flow through when the roof top solar is not connected (Victron MPPT controller) to provide charge current. Likewise, when I have the BB1260 disconnected, again while towing, and using the rooftop solar only the charge gains are bigger than when both charge sources are combined.

I'm definitely curious, this is the first time I've heard of such a thing. Searching around, doesn't seem to exist a lot, unless (maybe) your alternator and solar charge controller put out wildly different voltages.

Charging battery bank via solar and alternator simultaneously?

Sorry if this has been answered, I've searched online and read several theories without a definitive answer. I'm going to describe my proposed setup below. In the end, I'm trying to figure out if having the alternator charging the same battery bank as the solar is going to be self defeating...

expeditionportal.com

 

[spressomon]

One of the issues with the Sterling BB units is the lack of an app that allows real-time viewing of what it is doing (compared to the Orion) so it makes it more challenging to see the problem I am experiencing.

When I have experienced the problem, the LFP had been drawn down about 50% so when towing with both the roof top solar and the BB1260 connected, and the ability of this particular battery bank to accept up to 2C, I should see considerably higher current flow into the battery than I'm getting (bulk charging scheme from both devices). As I mentioned, I need to collect hard data...

But, IMO, utilizing an Orion(s) and Victron MPPT controller(s) allow real time viewing into what and how each device is operating via the app 'under one roof'. Before its all over I plan to swap the BB1260 for one or two Orions.

 

[spressomon]

See 3. Synchronized Charging - More Details here https://www.victronenergy.com/upload/documents/Manual-VE.Smart-Networking-EN.pdf

Nate, EXPLORIST life - DIY Campers talks a little about it at 6:15 here:

 

[e9999]

FWIW -maybe nothing- I do remember vaguely something along the lines of thinking, after reading literature on the Redarc controllers- that they were surprisingly much less customizable in terms of charging cycles than the Victrons. Like you could pick a general profile for a given type of battery out of a (very) few, but you could not fine tune the numbers to your liking, like I can with my Victron. Maybe it was just the specific units I looked at.

 

[joltman]

FWIW -maybe nothing- I do remember vaguely something along the lines of thinking, after reading literature on the Redarc controllers- that they were surprisingly much less customizable in terms of charging cycles than the Victrons. Like you could pick a general profile for a given type of battery out of a (very) few, but you could not fine tune the numbers to your liking, like I can with my Victron. Maybe it was just the specific units I looked at.

I think this is still correct. There's nothing I've seen mentioned in documentation for Redarc that would let it change some of those charge settings. So yeah, I think Victron wins here. But it also means you _need_ those stats from the battery manufacturer to put into Victron.

 

[e9999]

IIRC, Victron had some preprogrammed default cycles built-in already for the usual battery types. Probably good enough already. But those can be tweaked as you wish, all the better from there on. But, yes, for that to help, you may need to find out the specs for your specific battery.

 

[spressomon]

Here's a good video explaining Victron's V.E. Smart Network, features, etc.

 

[e9999]

interesting to watch. The one thing that came to mind, though, is that the Victron Bluetooth have such a short range, it's pretty limiting. Plus what happens in 5 years when the Bluetooth standards have changed, will they all still work fine together and with your devices? Wireless is great, but wired seems more durable. It's very elegant now, though, I must say.

 

[joltman]

I think if you're going down the Victron route, you should design your system around the Cerbo GX. Make sure your components can do the different VE connections (bus, can, etc)

 

[tbisaacs]

Thanks for sharing @sdnative! Making some notes for future upgrades on my setup

 

[joltman]

@sdnative I've now got the Trekboxx and need to start making some decisions. I believe I can fit a Battleborn 100AH BBGC2 under the driver's wing on the drawers. Securing it down shouldn't be a big problem. It will not fit in the battery tray from Trekboxx, but I think with some metal tabs and straps the battery wouldn't go anywhere. I am curious about the dimensions of your battery box. I'm not opposed to building my own battery. My only concerns have to do with vehicle insurance if something were to go awry.

I was considering the 280AH cells, but you mentioned issues with vibration. I'm trying to find more info there. Any other issues you've noticed? Thanks!

EDIT:

And my other question was, are you grounding the battery to the chassis? I see you've got the isolated Victron Orion smart charger. If you're not grounding the battery to the chassis, are you experiencing any issues with your ham radio?

 

[sdnative]

@sdnative I've now got the Trekboxx and need to start making some decisions. I believe I can fit a Battleborn 100AH BBGC2 under the driver's wing on the drawers. Securing it down shouldn't be a big problem. It will not fit in the battery tray from Trekboxx, but I think with some metal tabs and straps the battery wouldn't go anywhere. I am curious about the dimensions of your battery box. I'm not opposed to building my own battery. My only concerns have to do with vehicle insurance if something were to go awry.

I was considering the 280AH cells, but you mentioned issues with vibration. I'm trying to find more info there. Any other issues you've noticed? Thanks!

I am surprised that the Battleborn 100Ah battery doesn't fit. I would think that would be the standard dimensions to which to design a vehicle interior battery box.

EDIT: you referenced the BBGC2. Why that one? I was thinking of the standard group 27 sized BB10012.

My "battery" measures 13.25" x 5.5" x 9.25". This is just the wood "box" and doesn't include the BMS, fuse holder and shunt hanging off the ends. This is with 8 cells, so a 4 cell battery, comparable to the Battleborn in capacity, would be significantly shorter.

This is one source for the less than 200Ah cells in off-road vehicle (this applies to marine but same concept), and it is an excellent read.

Assembling a Lithium Iron Phosphate Marine House Bank | Nordkyn Design

This article describes the process of designing, assembling and balancing a lithium battery bank for use on a yacht.

nordkyndesign.com

There are probably also discussions on DIY Solar Power Forum (vehicle mounted systems sub-forum) and I am sure many other places around the net.

Vehicle Mounted Systems

RV's, Vans, Trucks and More! Typically 12v, and 100-1000w, but the limits are endless!

diysolarforum.com

 

[joltman]

The battery tray that I was sent is about 12" long, and about 6.75" wide. Its not big enough for the BB1001H 100AH heated battery according to the ASSEMBLY DRAWING. It might fit in the wing without the tray. My concern is that there is almost 12" of room that would fit the 6.75" wide battery. That is very close and I wouldn't want to buy that battery without being 100% certain it would fit.

I did go out and verify my tray measurements and the tray _would_ fit the BB10012 non heated battery according to the ASSEMBLY DRAWING. I was thinking I'd need the warming battery as it can get cold in my garage over the winter. However, after spending the day watching videos on DIY builds, there are some pad heaters that could be placed under the battery on the tray that can be activated by a temp sensor. That could solve the issue.

Also, I was curious about the battery to chassis grounding and your ham radio. Have you had any issues? Thanks!

 

[sdnative]

I am not familiar with the Trexboxx, but I don't think the heated battery would fit under the ARB wing, most likely the non-heated wouldn't fit either without scratching up the plastic panels and blocking the AC intake vent.

I wouldn't mess with trying to DIY a heating blanket on a production battery like that, unless you absolutely need to fit the battery under the wing. If you think you will need heating, just get the heated version even if it means locating it somewhere else.

Normally my battery would not be grounded to chassis, however because I am using an isolated DC/DC charger, and I ran some DC loads off of the Blue Sea 5046 using just the positive wire, I had to add a jumper to complete the circuit (basically converting the isolated charger to non-isolated).

Regarding the radios, no issues so far, although I haven't needed to use the main radio in a condition that would generate much heat. Mostly low power chat with others in the group with HTs.

 

[teejnut]

I am not familiar with the Trexboxx, but I don't think the heated battery would fit under the ARB wing, most likely the non-heated wouldn't fit either without scratching up the plastic panels and blocking the AC intake vent.

I wouldn't mess with trying to DIY a heating blanket on a production battery like that, unless you absolutely need to fit the battery under the wing. If you think you will need heating, just get the heated version even if it means locating it somewhere else.

Normally my battery would not be grounded to chassis, however because I am using an isolated DC/DC charger, and I ran some DC loads off of the Blue Sea 5046 using just the positive wire, I had to add a jumper to complete the circuit (basically converting the isolated charger to non-isolated).

View attachment 3090363

Regarding the radios, no issues so far, although I haven't needed to use the main radio in a condition that would generate much heat. Mostly low power chat with others in the group with HTs.

I have a similar setup and no issues with my Ham radio either.