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Cheap 4kwh LiFePO4 batteries from Batteryclearancewarehouse

That was what stumped me why so many posts, unless there is 2 batteries in each cell.
Bet if you Cut the busbar between the upper and lower at each end , .how many 4 post cells are out there, never saw any, or seen anything like this.
 
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I have seen several of these long style BYD battery cell's where there are a two posts on each of the positive and negative ends.. The bus bars are these are some sort of compressed layers of foil. It's a single cell though or at least it does not act like two isolated batteries in one unit.

In fact when Dan was by the warehouse the other day he spotted a stack of them on a pallet from a different type of BYD bulk battery unit.

Seems like a BYD thing.
 
Never seen any battery like that, how would the chemistry react inside with 2 positive and 2 negative posts you would think it would be all over the place, and why 4 not 2 posts that is my head scratcher, maybe better battery management with 4
 
it is all flat on the inside just the exit/entry is via two posts, normal anode/cathode layout.
 
The two posts on each cell could be some sort of modular design flexibility.. if a BYD client wanted a 1s8p cell layout, it might be an easy way to offer a custom cell configuration.. I don't recall ever seeing a long bus bar run with these before. They always seem to be linked one post to another post.
 
The cells remind me of these. some of these use to come with two posts on each side of the cell.
See also https://www.diyelectriccar.com/forums/showthread.php/inside-gbs-cells-84307.html
Bad links on the first two but the diyelectriccar site picture showed two electrically separate cell assemblies inside a outer casing.

I'm suspecting more and more that these cells are really two cells in one casing. Simple way to find out: measure the resistance from one pole to its neighbor and voltage from one post diagonally across the cell to the opposite post on the far end.
 
Multiple posts because these were probably daisy-chained into a very high voltage, high AH system. A solar farm, if that's where these came from, would not use 24v...probably more like 600v. So with ~24 in series and probably even more in parallel, extra posts makes a lot of sense.
 
So who has ordered from this new company? Anyone receive tracking numbers yet? I placed a very small test order last week to test the batteries, and the vendor, before placing a larger order. I'm always a little skeptical of brand new companies with brand new websites selling things through back-channels (internet forums) to people eagerly willing to spend money on good deals. I'm pretty sure everything is legit, but I'd be weary of placing large orders until some actual shipments have been confirmed. And not from convenient "locals" ;). Anyone?
 
Supervstech, drives by their business everyday, More into recycling electronics than retail online
 
Supervstech, drives by their business everyday, More into recycling electronics than retail online
I drive EVERYWHERE in the Charlotte area every day, so while I do not know where the Charlotte location is, I’m sure I can guess... my plan is to visit the main Raleigh location and go over plans with Guy.
I might bring back a trailer load of panels and batteries if anybodywants to pick up in Charlotte free shipping...
 
Hey @maxx123 You said you used the copper that came with the battery, could you elaborate on this a little? I completely missed it when you first mentioned it.
If you look at the neg post the plate that is bolted to it run all along the side think 4 screws holding it connects to the back plate then goes to the neg or #1- cell 3.2 v .. I took the black tape off cleaned it up ,cut soldered drilled, cursed
If you are happy with the main posts in the front, leave it, well built, my space I have for them is sideways so I moved posts to the side. A lot of work, fun too, Trying to get both battery mods done, before Xmas. out of the house..
 
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If you look at the neg post the plate that is bolted to it run all along the side think 4 screws holding it connects to the back plate then goes to the neg or #1- cell 3.2 v .. I took the black tape off cleaned it up ,cut soldered drilled, cursed
If you are happy with the main posts in the front, leave it, well built, my space I have for them is sideways so I moved posts to the side. A lot of work, fun too, Trying to get both battery mods done, before Xmas. out of the house..
Ah, I was thinking there for a min that there was a copper plate behind the posts that the aluminum bus bars attached to which then in turn attached to the terminals. If there was I was going to bolt my big copper bus bars to it and be happy with the copper/copper connection, guess I'm stuck with copper/aluminum. Oh well, nothing a little sandpaper, noalox, a grade 8 bolt and a couple of washers can't fix.
 
Ah, I was thinking there for a min that there was a copper plate behind the posts that the aluminum bus bars attached to which then in turn attached to the terminals. If there was I was going to bolt my big copper bus bars to it and be happy with the copper/copper connection, guess I'm stuck with copper/aluminum. Oh well, nothing a little sandpaper, noalox, a grade 8 bolt and a couple of washers can't fix.
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Actually think it is copper plated tin, thought the flexible part was a fuse type, maybe is. Also able to expand as the cells swell. Without damaging the cell posts, (smart) so anyone
With lifepo4 batteries cells using copper bars with no expansion could damage the cells, if battery expands.
 
the flex part of the bars is just to build the thing easy vs rigid bars. i find it neat how those parts are made. some kind of anti flux was applied to the part that need to flex and the rest of the thing dipped in tin. thats how you get parts of it rigid and not.
 
So who has ordered from this new company? Anyone receive tracking numbers yet? I placed a very small test order last week to test the batteries, and the vendor, before placing a larger order. I'm always a little skeptical of brand new companies with brand new websites selling things through back-channels (internet forums) to people eagerly willing to spend money on good deals. I'm pretty sure everything is legit, but I'd be weary of placing large orders until some actual shipments have been confirmed. And not from convenient "locals" ;). Anyone?

I put in an order Saturday Dec 14 10am for 4. Got a message that they shipped on Tuesday the 17th 7:45am. I'm just over 900 miles away in Arkansas. Got a phone call on Wednesday the 18th saying the truck will be there tomorrow afternoon. Delivered on Thursday the 19th 2:15pm. Considering it's the week before Christmas and I ordered on the weekend I'm happy. Sadly, I have to wait for a few more parts to come in before I can capacity test them.
 
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