timselectric
If I can do it, you can do it.
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I'm still deciding. Space is limited for me. I haven't come up with a location and orientation, yet.
EVE 280AH cells fast shipping and great price!
- Thread starter Josh Gibson
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@Josh Gibson have you, or anyone else, considered how to do a flexible or semi-flexible busbar for these two stud terminals for use with inline cells under compression?
I had thought about just buying some 2ga. or 4ga. (to handle 200A) flexible OFC silicone wire and making two small loops per terminal, but with lugs and wire it will get a little costly. Even at that, the radius of the loops would have to be pretty tight since the lugs have to mount at 90*, plus you have to do 2x for each set of terminals.
I suppose another similar option would be to use the same lugs and use multiple runs of a smaller diameter wire (maybe 2 x 8ga or 3x 10ga.) per lug for more flexibly.
I also thought about cutting the supplied busbars and soldering a small section of heavy gauge wire in between to create a little flex, but I'd guessing soldering that much mass would be a PITA.
Another option would be make custom semi-rigid busbars out of copper pipe and hammer in a "kink" in the center for a slight amount of give. Probably less forgiving and wouldn't be tinned, unless someone wanted to do a DIY tin-job.
I'm sure there are other ways to skin the cat... Either way I'd ideally like to use compression and I'm reluctant to use the solid bars as they would likely stress the terminals.
Any thoughts, other than "just don't use compression"?
I had thought about just buying some 2ga. or 4ga. (to handle 200A) flexible OFC silicone wire and making two small loops per terminal, but with lugs and wire it will get a little costly. Even at that, the radius of the loops would have to be pretty tight since the lugs have to mount at 90*, plus you have to do 2x for each set of terminals.
I suppose another similar option would be to use the same lugs and use multiple runs of a smaller diameter wire (maybe 2 x 8ga or 3x 10ga.) per lug for more flexibly.
I also thought about cutting the supplied busbars and soldering a small section of heavy gauge wire in between to create a little flex, but I'd guessing soldering that much mass would be a PITA.
Another option would be make custom semi-rigid busbars out of copper pipe and hammer in a "kink" in the center for a slight amount of give. Probably less forgiving and wouldn't be tinned, unless someone wanted to do a DIY tin-job.
I'm sure there are other ways to skin the cat... Either way I'd ideally like to use compression and I'm reluctant to use the solid bars as they would likely stress the terminals.
Any thoughts, other than "just don't use compression"?
Struc
Collecting Parts!
Check out LithiumSolar and Off Grid Garage on YouTube. Andy from Off Grid Garage just did a video on different bus bars and Lithium Solar did one quite a while ago about his setup and the bus bars he finally chose which were multi-layer copper.
Unless I missed it, I don't think either has addressed this new twin post design yet.
LithiumSolar
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These are the busbars I used on the drilled LF280's and no, they do not address the new twin post design.
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Thinking about this more, I do have some thinner copper in roll form laying around that would be flexible enough if a hump was left in it.
timselectric
If I can do it, you can do it.
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Two smaller cables with lugs, for each post. Would be a great way to make the connections. Would be more flexible than one large cable.
LithiumSolar
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A long strip of something like this folded over several times ("S" shaped to allow current to flow better) with a hump in the center and drilled at either end might work. Thoughts?
That's a thought, but it partly defeats the advantage of having two studs per terminal.
timselectric
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Just drill or punch, the second hole.
I guess you could also just drill the two additional inner holes into those bars as well. Do they actually offer enough "give" to them to relieve the terminals, or not really?
7Days_Late
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LithiumSolar
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I'd say so...
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How about down the lenght of the bar, where someone might actually need the give, lol
LithiumSolar
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No, they don't really give length-wise. They would accommodate a little pressure compared to solid bars, but nothing compared to using a piece of fine-stranded wire with lugs (assuming I'm understanding the question correctly). However, if someone's cells bloat up, I would think the tendency is to fan out - ie bottom spread more than the top. Just my thoughts/opinion though...
timselectric
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I'm not sure why you would need flexibility, if the cells are compressed.
Fixed compression (where it's tight even at 0% SoC), maybe not. But spring-loaded like mine, absolutely needed. (at least for the cells that expand & contract like the EVE 280's.. not all of them appreciably expand & contract).
Ideally you want about ~12-14 psi consistent compression on the cell pack. Obviously the sides with the most surface area will 'give' the most. The most common and consistent way to keep that pressure is by loading the ends plates with springs. So while the cell pack is under pressure, it's not totally confined from internal movement either. According to EVE, the side width dimension of each cell grows and contracts ~1mm as it goes from one end to the other of it's SOC. If all the terminals are locked together in the spring-loaded 16 cell pack, the terminals are going to be either pushed or pulled depending on the cells SOC... So ideally you have a flexible busbar which will relieve this pressure.
If you're not using compression to extend the life of the battery, just leaving a small gap between the cells for them to 'breath' keeps the stress off the otherwise locked together terminals.
timselectric
If I can do it, you can do it.
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Makes sense, thanks.
Michael Johnson
Michael Johnson
Where are "Amy and Jenny"? How do I contact for a quote? Thanks
Maintenance guy
New Member
They are both on this site somewhere. They both work for the same company and have US warehouses
Michael Johnson
Michael Johnson
Yeah, figured it out. Both are reps for DOCAN. Thanks
Hello
I just got quotes from Amy, and all should know that there is a new VAT tax added, to your order, and that plus the normal Alibaba fee is about a 10% adder to whatever you buy. I just checked shipping to my address and these brand new cells from this company are cheaper then the price Amy can quote for 32 cells with the high shipping costs and the new 10% adder for VAT and Alibaba fee from China. I placed an order earlier today, and am going to cancel same and get these.
I can share more details via private email.
CPU
Bud Martin
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How about giving the link to the 'this company' instead of private email?
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