DIY 57kwh 48v EVE280k build

[Offthewall]

Let’s get started. This will be my 3rd build of a lithium battery for solar but my first LifePO4 build. My first build was a 23kwh NMC build using 30ah batteries salvaged from an EV. The second was a “power wall” style using 140 21700 cells from a model 3. It powers my gate for my house and works great! I’ll show it off at some point.

For this build I am using 64 of the EVE280k cells. I have not decided exactly on the configuration yet… 4 separate banks, 2 banks made in a 2p, or 1 bank with them 4p???

Originally I had wanted to put them in a server rack I have cut down to a 27u size but I just don’t like how it looks and buying a new rack would cost too much at $900. I then thought of putting them in a harbor freight tool chest $370 but I’m not sure it would hold up well to this much weight!!! So I ended up buying a shelf from Sam’s club to put them on… it was cheap enough at $75!!

 

[Offthewall]

Well I think I like the shelf build with the shorter section… this way I can mount the charge controllers under the inverters…. Or should I put them on the adjacent wall (away from the sink that I may move or remove)

 

[Offthewall]

Been sick…. Finally got to do a little work. Ordered 4x JK BMS’s 150a… still not 100% on how I will configure them… keep leaning to a 16s4p configuration vs a 4 x 16s….

 

[RV10flyer]

I like my 10 ea separate 280aH batteries and 150/200A BMS's. JK is the only one I'll buy from now on. I've tried 8 brands. I installed 100A dc breaker, 2 ga fine wire, up front with the BMS, LCD and 125A class T fuse between cells 8 & 9 in the back using two busbars to connect. 143kWh. Battery #11 for Winter Solstice and Christmas.

 

[42OhmsPA]

Looks like an awesome setup so far.
I have that same shelf, used for other storage. I would not feel comfortable putting all that weight on each shelf, even though they are rated for it. I would set the batteries on a 'plate' that spreads the load over the rails of the shelf. Just a suggestion.
I purchased one of the other shelves they sell with plans to fill it with cells, that plans changed quickly once I put the cells on it. They don't make them like they did years ago, cheapened up significantly.

Good luck with the build.

 

[Offthewall]

I like my 10 ea separate 280aH batteries and 150/200A BMS's. JK is the only one I'll buy from now on. I've tried 8 brands. I installed 100A dc breaker, 2 ga fine wire, up front with the BMS, LCD and 125A class T fuse between cells 8 & 9 in the back using two busbars to connect. 143kWh. Battery #11 for Winter Solstice and Christmas.

143kwh… holly hell that’s a big battery bank!!!!

 

[Offthewall]

Looks like an awesome setup so far.
I have that same shelf, used for other storage. I would not feel comfortable putting all that weight on each shelf, even though they are rated for it. I would set the batteries on a 'plate' that spreads the load over the rails of the shelf. Just a suggestion.
I purchased one of the other shelves they sell with plans to fill it with cells, that plans changed quickly once I put the cells on it. They don't make them like they did years ago, cheapened up significantly.

Good luck with the build.

Each shelf is rated for 600lbs. The batteries are <400 but yea I’m still a little concerned… I’ll probably reinforce it somehow.

 

[RV10flyer]

143kwh… holly hell that’s a big battery bank!!!!

2000 lbs. I built the 30" x 84" work bench with two shelves out of wood, covered in cement board. It will power our house for 3 days not conserving, 6 days if we cut back a lot.

 

[Offthewall]

My take on cell compression…. A little foam, 1/2 acrylic, and a couple tie straps…

 

[RV10flyer]

My take on cell compression…. A little foam, 1/2 acrylic, and a couple tie straps…

View attachment 113087
View attachment 113088

Bingo. That's how all 10 16S batteries are. The straps get tighter the higher the charge goes. No springs necessary. No more additional pieces (threaded rod) that can cause a short.

 

[Offthewall]

Progress has been slow…. I have been waiting on my BMS’s to show up… they finally have! 1 went with JKBMS in 1a20s15p (150 amp) x 4… added 125 amp breakers… the cross over busbars are 4gauge x 2… should be fine but will check with thermal once everything is up and running.

 

[Offthewall]

Well 2 days ago I had a little accident… when you think you are being safe enough… better double check! I went to connect the bms and one of the ground lugs came off the post and hit the positive… instantly vaporizing the copper ring terminal and leaving me with a nice little burn. I’m just glad it wasn’t worst! Funny thing is my EMT inservice class the following day was on burns…

 

[Offthewall]

But after all that I got the batteries together (almost… short 3 nuts… thanks a lot 18650batterystore so much for giving me extras….)

 

[Offthewall]

Ran everything to a victron lynx…

 

[Offthewall]

Still a little early to tell but I have 1 cell that is a lot lower compared to the others….

 

[OzSolar]

Thanks for the update. How's the hand?

 

[Eason Zeng]

Hello! do you consider putting them in the battery box?EEL has the 48V 16S DIY stackable box, you can take a look

 

[houseofancients]

Hello! do you consider putting them in the battery box?EEL has the 48V 16S DIY stackable box, you can take a look

do you have a link to it, btw it looks suspiciously a lot like the seplos mason box

 

[Eason Zeng]

do you have a link to it, btw it looks suspiciously a lot like the seplos mason box

here is the link:https://eelbattery.myshopify.com/pr...type-without-cellssuitable-230-280-302ah-cell
Seplos box minimum order number is 10 set

 

[Offthewall]

Hello! do you consider putting them in the battery box?EEL has the 48V 16S DIY stackable box, you can take a look

I see no advantage to put them in boxes at this point