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I had a head start on the battery boxes. I designed and built a prototype based on a mock up "dummy" pack last month while waiting for cells to arrive. I decided to hold off building the other 3 boxes until I confirmed everything is going to work. I didn't encounter any surprises when I put...

Pic below of my steel framed boxes with compression. Lishen 272 cells with overkill bms's. HDPE strips as hold downs on the tops, black hex plywood with phenolic resin coating for the panels. All the compression is basically with captive nuts and grub screws. Materials are pretty cheap, but...

I've seen much debate on Loctite vs. helicoil, etc. to strengthen studs. I'd say helicoils are the way to go if you want the strongest option, but I decided to go with red loctite since my threads seemed pretty good. I did my first 4 cells and ended up making a bit of a mess of the terminals...

I went ahead and top balanced all 4 packs. Since I had some jumpers made previously, I didn't have to take apart the packs and it didn't really take any time. It was pretty quick pulling bus bars and leads and just sticking the jumpers on. It was just getting over the mental hurdle of pulling...

I just completed the install of my solaria 400w panel. Pretty tight fit behind the AC unit without overhanging the back, so there will be some shading from the AC at times. The AC is as far forward as possible with the hole right up against a ceiling rib. I fabricated the mounting brackets...

It's alive. All the core stuff is installed and running. I still haven't run the cable to the chassis battery/alternator, so the Orion B2B chargers are not connected yet. I ended up top balancing all the packs again. The cells had been sitting loose for about 7 weeks and I had one cell...

Getting close. Batteries are fully assembled. I'm in the process of charging up each pack before I do some charge/discharge testing of the 4 running together. I figured it was worth running a couple more tests before installing to make sure I don't have any hot spots or bad connections.

Thanks. I definitely have a long way to go, but I'm already enjoying the electrical system and using the van. I'm a pretty serious cyclist and it's already been to a bike race a couple hours away and the AC was nice. I've also been using the van as home base for a couple other local cycling...

From what I've seen on this forum, even the "good" suppliers have bad moments. None of these suppliers are selling new Grade A cells. These are grey market "reject" cells of varying quality and the pricing reflects that. They advertise them as "new, grade A" rather than describing what they...

Battleborn doesn't use prismatic cells where compression is an option/recommendation. I think the whole compression thing is somewhat of a hand-wringing exercise. It might be a good idea to do it, but "need" is up for debate. For the larger packs (280Ah for example), the spec sheet says...

I've been working on the rear wall for all my electrical equipment. It's been slow going, lots of thinking and small steps. With the weight of the inverter and batteries, I really wanted make sure it was solid, so I used a mix of 1/2 hex board with 1/8 steel support. I used a bunch of rivnuts...

No progress on battery boxes this weekend. Out of the blue, my van got built and delivered and I picked it up this weekend. I wish I had not been taking my time, now I feel like I'm behind. Oh well, it's all good. I installed a bed in the van today and I'm still running capacity tests on all...

You can buy the eaton branded version of those MRBF terminal fuse blocks for a fraction of the blue sea price. It's the same thing, just doesn't include the rubber hood (but you can buy it separate). At least for the singles, not sure about the doubles...

I'm new to building batteries, but I can't understand why anyone would risk turning the power supply up past 3.65v. Is it really that much faster? I don't understand why. I have a cheap 10a supply and set it to 7a. It pushes at 7a until the cell is almost full whether I have the voltage set...

I've continued to cycle the batteries pretty much every day, running 2 at a time in parallel. I've been charging to 14.1v and then recharge once they consume 544Ah (272Ah x2). They are typically getting close to 12v at that point, so they seem like they have full capacity without hitting the...

Just finished my first individual cell test on my lishen 272’s. 287 Ah at about 6.5a discharge. Started at 3.62v and finished at 2.62v (cut off for tester set to 2.5v, but it has a bit of voltage drop).

There is really no reason the manufacturers couldn't repackage the current mini split technology into a single efficient rooftop unit for the RV market. Most of the current rooftop RV AC's pay no attention to efficiency, they are basically the same technology that has been around for 40 years...

I finally completed individual cell testing today. 1 cell every 2 days, right on target after 32 days with no issues or surprises. Final results below. Capacity ranged from 282.29 to 288.84 AH. They were all tested using the same protocol. I detailed that in a prior post. Bascially, I...

Back to the batteries... I finally finished the other 3 battery boxes and installed all the cells. I decided to switch from hdpe to this hex board plywood material I've been using for the van. It's plywood with a hard shell coating on both sides. Next step is to get the BMS's installed and...

From what I've seen, the Overkill BMS certainly tries to track Ah's in and out and use that for capacity, but it doesn't line up perfectly with the smart shunt. See screen shot below of my battery discharging. A few thing to note: I set the original battery capacity to 272Ah, but the BMS...

Those cells Will tested were actually lishen 272’s, not eve cells. I think others have reported that the eve cells don’t stack flat, so I wouldn’t be too concerned

I was using loctite to permanently install my studs, not to attach the nuts. It's really about avoiding the stripping problem and making the stud install solid. Red loctite is used for this and you would never want to use it on the nuts because it's basically permanent. Blue loctite is used...

The stud is not your electrical connection, the bus bar to terminal mating surface is. Stainless is a poor conductor whether it's got loctite on it or not. These studs and the limited number of aluminum threads is not ideal in a lot of ways. I'd say helicoils is probably the best/strongest...

That’s a low flowing well and it’s very easy to fry a well pump if they run dry. For any well that has a pump that can pump more water than the well produces, a pump saver device should be installed. They constantly monitor the electrical load and immediately shuts down the pump when it senses...

Most certainly, I'm just trying to understand this stuff better and I find it interesting. It just seems odd to me that with all the processing power and communication between devices in these modern systems, the charge settings are still set at the individual charger level @ X volts for y...

My lynx setup connects a MPII w/SCC, 2 Orions, and the DC load center. It's a bit of a compromise and you need to size wires and fusing carefully when doubling up on single fuses. The wire used to each orion was big enough to work with the 100a fuse that covers the combined circuit. The scc...

I'm building a battery bank for a new sprinter van I've got coming next month. Original plan was battleborns or SOK's, but I decided to go the DIY route after spending some time on this site. Thanks for the all the great info! The plan is 400watts solar w victron mppt, Victron 12/3000...

The cells looked pretty consistent for voltage and IR. The 2 "non-blue" vents were a little lower on IR and just slightly higher on voltage. Rather than starting with the top balance, I built cells 4 into a pack with the BMS to get some Ah's into them. I've been pushing ~80a into them for...

I'm all for destructive testing and fun, but someone needs to get that guy some safety glasses...