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I built the packs in two separate boxes, each with its own terminals, so that they are easily removable. The current readings I am getting with the ammeter are rather stable, no worries there. Impossible to find a hotter connection by touch. I wish I had an infrared temperature sensor. What I...

I assume picture is a loctite equivalent? I have epoxied grub screws in my Eve 280’s and tighten/loosen the busbar nuts with an Allen key in the grub screw and small wrench for the nut. I will do some testing to see if blue loctite is still too strong for the nut to be unscrewed safely.

Actually, nothing has changed. When I connect the packs in parallel and hook them up to the inverter, the two BMSes report different discharge currents, i.e. 7A and 4.5A, and I get the same readings when I measure the currents on the two parallel jumpers (solidly crimped 2/0 wires). The total...

Thanks for the reply. Yes, by the first cell, I mean the one that is the negative connection (through the BMS). I will do more troubleshooting when I get home in a few weeks.

There is no "normal" layout yet, but here is a picture of the temporary setup to discharge the packs some until I can install them in the van. Please note that I just removed the fuse on the positive wire going to the inverter (to see if that makes a difference - no difference).

In the normal layout, the positive will go to a T-class fuse and the negative to a shunt.

I also purchased four of these, and received them yesterday. It will take a few weeks before I work on a proper insulated enclosure. Out of curiosity, I connected one directly to a commercial 12V LiFePo4 battery that I already had and measured 1,6 A with my Klein clamp meter. The pad itself did...

I have two DIY 4S LFP 280Ah packs in parallel (560Ah) in my van, each with a 120A Overkill BMS. These are Eve cells purchased from Basen. I did top balance the cells when I received them, but only tested the capacity at 40A, as I believed I would very rarely be drawing more than that (I have...

Corbury, did one of your cells actually reach 3.97 volts? I do not see you mentioning that in the thread.

Very true. Having used Loctite in other applications, I can say that it will not have the same density out of the bottle if you do not shake it well before use. If I was to start over, I would use JB Weld again.

I installed my 16 grubscrews in one session and waited 48 hours before I reassembled. I do not have a torque wrench to measure (yet), and I am still very careful when tightening, but the studs feel pretty solid. I re-top balanced at 3.64 V and then assembled one 4S pack with the BMS. I did...

Correct. If I read the spec sheet well, the overload limit varies with temperature.

I am now using these busbars: https://www.aliexpress.com/item/1005003230279908.html?spm=a2g0o.order_list.0.0.21ef1802kTgGi6 Flexible enough to allow some play, and the connecting "plates" allow for good tightening. I also used blue loctite in gel form on the grub screws to help prevent the...

Thanks, that’s good to know! I ordered the small torque wrench you linked, so I will have a more precise idea.

Both BMS’s are now sold.

I threaded the screws in by hand (easily) to the bottom, and then backed off a bit. The epoxy being more of a paste, I think it would have been more difficult to drop the right quantity on the bottom. I felt I had a better chance to have more JB Weld on most of threads this way. I do not have...

Yes, both valid points, it is probably best to avoid triggering the BMS as much as possible. I will revise the settings accordingly.

I purchased some Permatex activator/primer and am doing some tests these days to see how Permatex threadlockers can work with SS grub screws and nuts (I do not have aluminum to play with). I already had the blue Permatex threadlocker, so that is what I am using now. I am thinking of using the...

Thanks for the reply. I also purchased the same Eriflex bar and just cut one bus bar to see how flexible it can be at this length with the three layers. I am finding it a bit stiff for the purpose of avoiding stress on the terminals. The diagonal setup sounds like a good idea; I am wondering if...

I do not have one, but would a highly reflective roof not somewhat help? Like metallic silver

This will be for a van 12V 560Ah system, made of two 280Ah batteries each with an Overkill Solar BMS. I will top balance the cells when they arrive. I understand the BMSes will also balance the cells at the top of the charging cycle (hopefully the cells will be at close enough SOC for that to...

Thanks for the info. I have done quite a bit of reading so far, but I had not read the Nordkyn articles. Still learning. I will be building two 12V 280Ah batteries, and I am still looking for boxes or enclosures to safely contain everything (fixture, bms, cables) in a reasonably compact format...

Terminal treatment: terminal face sanded with 600 grit paper, cleaned with acetone; studs JBwelded into terminals; braided bussbars with smaller holes drilled and contact face filed, sanded and cleaned with acetone. No corrosion inhibitor, no washer on top or underneath the bussbars, serrated...

Was this in an insulated enclosure?

Great set-up. I love the fact that the heating circuits is integrated into the BMS. My heating circuit is also made up of 10W heating pads (with an external thermostat), however the wiring and wire insulation on the pads are much more flimsy compared to yours. Would you mind sharing your source...

On the subject of busbar current carrying capacity... A question for the experts. Since my two 280Ah batteries will go in my van, I felt it was best to have braided busbars to prevent stress on the cell terminals (studs). So I purchased these large braided busbars, rated for 250A, with M10...

Got it, thank you!