That's what I do. Works very well, you can decide to tin it or not, and you can make it any length you want. The copper tube can easily be pressed together in a vise.
Xuba Electronics: DEAL - 280AH LiFePo4 cells. Purchase & Review
- Thread starter Steve_S
- Start date
That's what I do. Works very well, you can decide to tin it or not, and you can make it any length you want. The copper tube can easily be pressed together in a vise.
AussieInSeattle
New Member
- Joined
- Jan 2, 2020
- Messages
- 59
My Higee 120Ah cells from XUBA shipped today via sea. 16 of them for a golf cart battery build.
I uploaded the Specification sheet for these cells to the Resources section:
diysolarforum.com
Now the planning starts for creating a box and securing them into the golf cart. Is there a reason for not using something like SEABOARD (HDPE plastic) in combination with some aluminum angle? I'm more comfortable cutting HDPE than aluminum. Should the batteries be entirely enclosed or just the top to protect from shorts? My initial thought is to use HDPE sheets from the top and ends with aluminum angle to joing them together and then 3D print a top and bottom cap (like Frey/Forunte cells use) that accepts a threaded rod to lock everything together with the HDPE ends? Any thoughts on any of my questions?
I uploaded the Specification sheet for these cells to the Resources section:
Higee 120Ah Cells Specification Sheet
Received in July 2020 prior to ordering from XUBA on Alibaba. Lots of forum members ordering the 280Ah cells from EVE, but I went with the 120Ah ones and they are made by Higee. Huge thread on the XUBA buys here...
diysolarforum.com
Now the planning starts for creating a box and securing them into the golf cart. Is there a reason for not using something like SEABOARD (HDPE plastic) in combination with some aluminum angle? I'm more comfortable cutting HDPE than aluminum. Should the batteries be entirely enclosed or just the top to protect from shorts? My initial thought is to use HDPE sheets from the top and ends with aluminum angle to joing them together and then 3D print a top and bottom cap (like Frey/Forunte cells use) that accepts a threaded rod to lock everything together with the HDPE ends? Any thoughts on any of my questions?
Attachments
For my 8s 24 V battery build using the 280 AH LiFePo4 Xuba cells, I purchased a 6' long piece of 0.1875" x 1.00" copper bar stock from Online Metals and cut them into 14 x ~10.5 cm bars and 1 x ~11.5 cm bar (for the long piece) and drilled 5/16" terminal holes with a drill press. The reason I cut 14 bars is because when I first got the cells I wanted to top balance them with all the cells in parallel which required 14 pieces to do that (probable overkill). In my final 8s configuration, I use 6 x ~10.5 cm bars and 1 x ~11.5 cm bar. The other bars are in storage in case I ever need to top balance the cells again (or I buy more batteries ;-)).Ok, seems this is the active site for these batteries.... I asked on the "Just Placed an Order..." thread.... I received my batteries and can now see the problem of the busbars being ok side to side, but not end to end.. too short. Anyone know which online site to buy the right sized ones to fit the other way?
Just realized that in a 8s pack, I only need one such end to end busbar, right? That sucks! Hardly worth buying online... is there something at a hardware store? I remember others making their own... smashing copper tubing or something... are there flat pieces at a hardware store to just drill out the one needed? What have others making a 8s pack done? Just one longer busbar... can't believe it... thought it was at least two... .but the other two are the leads... and aren't connected....
Wow,... one longer busbar needed...
I don't have a photo right now, but they have to be steel, not aluminum... too heavy for aluminum, right? Someone confirm that? Is steel better or worse than aluminum? For an 8s setup, I only need one longer one... hardware store has both aluminum flat and steel... these look and feel steel.
Or possibly tinned copper?
You're right....not magnetic... so now I have to get a tinned copper to match or just a copper piece.... seems making my own is the last option here....
These are about 3.5 inches... and the 8s setup needs about a 4 incher to fit that one that crosses.
These are about 3.5 inches... and the 8s setup needs about a 4 incher to fit that one that crosses.
At the hardware store, two of the busbars sent, seemed a little thicker than the 1/8" stock I was looking at... so maybe ~ 3/16"?
PS... Or, that because of the gap between 2 pieces? Would buying a piece of 1/8" x 1" copper flat stock work? Just cut and drill to fit?
PS... Or, that because of the gap between 2 pieces? Would buying a piece of 1/8" x 1" copper flat stock work? Just cut and drill to fit?
Last edited:
Measured.... just over an 1/8" thick... two of them together so the screws don't bottom out, right? Is that the tinning process? adds ~1/32" I think, not a 1/16"... more like a 1/32".... so perhaps buy some flat copper 1/8" stock? Cut and drill to fit?
I see a 1" piece for sale... but the terminals are only about 5/8"... so trim that down too or just leave the extra width on the terminals? Isn't it easier or cheaper to buy a flat piece? or use my little sledge hammer on a small copper pipe piece? Do they sell copper pipe in small pieces? I'd only need about 4" for that one cross piece in a 8s build. Anyone know off hand?
I see a 1" piece for sale... but the terminals are only about 5/8"... so trim that down too or just leave the extra width on the terminals? Isn't it easier or cheaper to buy a flat piece? or use my little sledge hammer on a small copper pipe piece? Do they sell copper pipe in small pieces? I'd only need about 4" for that one cross piece in a 8s build. Anyone know off hand?
Last edited:
you would need 4 BMS that can each handle your inverters or your greatest possible load amps.
The answer to this depends heavily on your maximum current draw.
4S4P = 4 x individual 4 cell battery packs, so 4 BMS'
4P4S = 1 x 16 Cell battery pack, so 1 BMS
Then you will need a or 4 BMS that can cut batteries off at 280 Amp draw as that is the max any one bank can handle. If it were me i would go 2p4s2p that way each abnk can handle up to 560Amp draw although you wouldn't want to draw that for too long. This would also allow for just 2 BMS
Sgt Raven
Solar Addict
- Joined
- Feb 17, 2020
- Messages
- 1,079
A short piece of welding cable and two lugs. I used two longer ones I had when I paralleled my cells to Top Balance them. I had them already and only needed them for a short time. If I was to buy more cells, I would double my buss bar order. That would give me enough to connect them in Parallel and I could double up them when I built the pack.
Technically, the surge rating is 2 x 6000W. Normally we don't design around that, but normally the surge is a few milliseconds to a few seconds. With the Victron Multiplus, the surge rating is a 2 minute rating. I'm not sure if that can be ignored (that's a question as much as a statement). Of course if you don't have any loads that will exceed the 6kw combined rating of your inverters, than it can probably be ignored.
In either case, that is a really large inverter load for 12v.
Ignoring Surge: 6000W / 0.9 efficiency / 12v = 555A (275A per inverter)
With Surge: 12000W / 0.9 efficiency / 12v = 1111A (555A per inverter)
Last edited:
John Frum
Tell me your problems
- Joined
- Nov 30, 2019
- Messages
- 15,233
Assuming a power factor of 1 and 90% efficiency I make that 275 amps per inverter. That's 550 amps. The bms etc should be sized to tolerate a single string going offline.
Sgt Raven
Solar Addict
- Joined
- Feb 17, 2020
- Messages
- 1,079
I would think two 24V battery banks would be better for that kind of use.
Similar threads
