BMS recommendation for 4S 280ah battery

[gmoylan]

Ok... Big update here!
I start a new thread for this too...
Dual Overkill 120 amp BMS running in parallel WORKS GREAT- though per Steve at Overkill, it is not recommended.
I have 4s 280 cells, grade A... my plan is to get 4 more, but I wanted to plan for that time about 2 months from now for shipping. I also have a 2000 watt inverter I wanted to run, which should draw about 180 amps under my planned, short duration, max load. Wiring the BMS modules using a Victron BMV-712 and a hobby load tester, I was able to see the 60 and then 135 amp draw split between the two modules. It is not a perfect 50/50 split, but close... The BMV was showing the load split and the BMS reflected this as well! Both BMS show the same cell voltage. Charging using a AGM charger at about 20 amps is working fine too.
Does it work? YES! There seems to be zero issue in doing this too while bench testing.
My WHY is explained above... The how is here to. I am actually using TWO battery chargers too. I DID want the reliability, local prep with wires, etc of Overkill. Also the Stateside shipping speed.
While I didn't read about it on the internet, I did watch Will's video using two 60 amp Daly BMS in parallel...
I thought this through and checked everything step by step very cautiously...
NOT doing it on the cheap either... the two Overkill BMS were about $250 with lugs crimped, etc.

For the next few camping trips, I will be good to go until the next four cells roll in, then I'll split the BMS modules up for the two separate 4s sets!
Pretty stoked!
My comment above and the issue I have with one BMS is temperature related? Maybe? It works fine until it hits high/low/overcurrent. then it gets locked out of self reset with discharge turned off. Working it out with Overkill, but probably a faulty module...

@SoundinSpirit
Hey, looking to run the same set up with 2 100a JBD overkill BMS on a 280a 4S config. Any updates, pros- cons you can offer?
Thanks

 

[SoundinSpirit]

@SoundinSpirit
Hey, looking to run the same set up with 2 100a JBD overkill BMS on a 280a 4S config. Any updates, pros- cons you can offer?
Thanks

Sorry, just saw this. I didn't get a notification... So far, it's running great. The two overkill BMS are working perfect together. A week of camping and no issues at all. Only thing I'd recommend is NOT using the bolts included with the cells.
I used 20 mm stainless set screws with nylock stainless flange nuts and a lock washer.
Here are some links.
Washers : https://amzn.to/37vYmzW
Set screws for the cells: https://amzn.to/3dwVG91

Flange nuts: https://amzn.to/2ZBBuKY
I also used this battery box with great success :
https://amzn.to/3aBwdJp
Connection Lugs: https://amzn.to/2MdD7eK
I'm working on a video outlining everything too.... It just takes time, lol! Especially with kids. Will P. has a lot more free time than I do! Haha....