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Xuba Electronics: DEAL - 280AH LiFePo4 cells. Purchase & Review

Steve you are so rigid. Nobody is an ass for sharing the conclusions they come up with. Even when the conclusions come with little knowledge or experience.
That and many similar signs were posted in one of my Uni Science Labs.
Please just hit IGNORE for my posts. You really do not need to see anything I post.
Yes. Exactly whose conclusions were you referring to Steve?
 
Twas tossed out "generally" seems some missed the 2nd line and decided to take it personally I guess.
Leaping to Conclusions based on Assumptions and "personal feelings or opinions" usually results in someone looking like an ASS.
A sign that was posted in our Science Lab at Uni. True then & True now.
Whatever...
 
Twas tossed out "generally" seems some missed the 2nd line and decided to take it personally I guess.

Whatever...
Yes, no offense. I just thought it was some of your previous posts I was trying to summarize so I wondered where I went so wrong. It seems like right now the only thing we can hold these resellers to is the amp hour rating and even that is difficult. We are at their mercy since they throw around phrases like Grade A, matched etc but there is no standard definition. They simply can respond by asserting "Oh that is not what we meant by matched or Grade A". Or we meant Grade A for used cells we never said they were new. This board represents a combined group of Buyers and it seems we should use that leverage to at a minimum demand we are using the same definitions. It seems like what Steve is working on with Amy is a good start. Will's recent experience with BLS is another example. Yes, that was Will, but if we can use that leverage on behalf of the whole group we will be better off.
 
Hi everyone. I was thinking of doubling my EVE 16s set up to 2p16s. Lishen cells look like they're a good price. Can I just paralel them into my current set up?? So it would be 1 Eve cell paralleled with 1 Lishen cell and then 16s the paired cells.

Also on the conversation of torquing the screws I think 6-8Nm is way to much. I set mine to 2.5Nm and I feel it's enough. I originally tried to do this with a torque wrench and had very limited precision/success. I purchase an electricians Wera adjustable torque screwdriver and it's been great not just for the batteries but all the electrical work in my home.

The terminals are phsyically higher on the Lishens so you can't use a bus bar. If you find a physical way that works for you in a one-battery, then it might work for you - the big unknown is whether there's any material differences in IR between the two.
If you create two separate batteries and parallel those together, there's less of an issue.
 
With respect to all the discussion around torque - I can tell you first-hand that 7Nm will strip the threads. Not always, but I've done it at least once, probably 2-3+ times (undetected) now.
 
With respect to all the discussion around torque - I can tell you first-hand that 7Nm will strip the threads. Not always, but I've done it at least once, probably 2-3+ times (undetected) now.
I torqued a few to 70 inch pounds and it was way too tight. I think there is a Chinese to English translation issue with that torque spec.
They mean anything over the spec will pull out the threads for sure. That's not the meaning of our torque spec.
 
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I torqued a few to 70 inch pounds and it was way to tight. I think there is a Chinese to English translation issue with that torque spec.
They mean anything over the spec with pull out the threads for sure. That's not the meaning of our torque spec.

Yeah "The anti-torsion of pole is 8Nm. The torsion should be less than 8Nm when used." may literally refer to the cell terminal and not the thread inside. Who knows.

I don't know what kind of aluminum the terminal is, but, for example, looking up recommend torque specs for 1/4" 2024-T4 aluminum is somewhere between 5.1 and 6.4 Nm.
 
Yeah "The anti-torsion of pole is 8Nm. The torsion should be less than 8Nm when used." may literally refer to the cell terminal and not the thread inside. Who knows.

Could anti-torsion mean the holding back force on the grub screws?

In that case they would be saying hold back with 8nm and torque forward with less than 8nm.

Put another way, counterclockwise force of 8nm on the grub screw shaft and clockwise force of less than 8nm on the nut.

Just a SWAG.
 
Put another way, counterclockwise force of 8nm on the grub screw shaft and clockwise force of less than 8nm on the nut.
Interesting theory that assumes that someone is using grub screws instead of regular bolts. Or that the grub screws are not fixed with Permatex Red or JB Weld. I do think you have the "less than 8Nm" part correct. That would also apply to people using bolts.
 
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Interesting theory that assumes that someone is using grub screws instead of regular bolts. Or that the grub screws are not fixed with Permatex Red or JB Weld. I do think you have the "less than 8Nm" part correct. That would also apply to people using bolts.
I'm going to use a flanged grub screw. Any idea how much torque can be achieve with a hand tighten alone? I'm thinking if i hand tighten the screw with permatex red on bottom, once that cures, i should be able to torque to 5nm on the subsequent connections above the flange. The only part i'm dubious about, is whether i can get a great conductivity between the flange face and the cell terminal face (with the mearest smidgen of noalox between), if i only hand tighten?
Any views?
 
Interesting theory that assumes that someone is using grub screws instead of regular bolts.

Agreed.

That is the first example of anti-torsion I could imagine.

I have no idea what else anti-torsion could refer to.
 
Agreed.

That is the first example of anti-torsion I could imagine.

I have no idea what else anti-torsion could refer to.
When I read the datasheet here:
Remark: The pole is a double aluminum pole structure. The internal screw with size M6 is used in the poles. The anti-torsion of pole is 8 Nm. The torsion should be less than 8 Nm when used. The effective thread hole depth is 6mm.
If you don't read the intermingled information about screw size, I think it becomes clear that they are talking about the battery pole itself. Since "anti torsion" literally means "resist twisting", it could be written as:
Remark: The pole is a double aluminum pole structure. The pole can resist 8 Nm of twisting force. The twisting force should be less than 8 Nm when used.
The internal screw with size M6 is used in the poles. The effective thread hole depth is 6mm.
Separating the screw thread information out from the battery pole information makes it more clear.

So for instance, the twisting force could be caused by using the battery terminal to support the weight of a heavy battery cable. This has nothing to do with the terminal screw, but if the twisting force caused by the weight of the cable exceeds 8 Nm, the battery could be damaged.
 
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I'm going to use a flanged grub screw. Any idea how much torque can be achieve with a hand tighten alone? I'm thinking if i hand tighten the screw with permatex red on bottom, once that cures, i should be able to torque to 5nm on the subsequent connections above the flange. The only part i'm dubious about, is whether i can get a great conductivity between the flange face and the cell terminal face (with the mearest smidgen of noalox between), if i only hand tighten?
Any views?

Not much... assuming you can put 100 N (~10 kg or ~22 lbs) and the radius is 5 mm that's only 0.5 N.m and and educated guess tells me it's not enough to make a good contact. I'd recommend to put at least 2 or 3 N.m ;)
 
Not much... assuming you can put 100 N (~10 kg or ~22 lbs) and the radius is 5 mm that's only 0.5 N.m and and educated guess tells me it's not enough to make a good contact. I'd recommend to put at least 2 or 3 N.m ;)
No expert here but I agree. Definitely 4nm or less even if using any type of thread locker.. I get the feel of this from using my beam torque wrench. 4nm is tight. Just an observation.
 
Not much... assuming you can put 100 N (~10 kg or ~22 lbs) and the radius is 5 mm that's only 0.5 N.m and and educated guess tells me it's not enough to make a good contact. I'd recommend to put at least 2 or 3 N.m ;)
Thanks for the calcs BiduleOhm. Thats a pita, as i only just purchased a torque wrench that goes down to 5nm. Wishing now i had got the 'bike' ones that go down to 1nm. Oh well :-(
 
I'd recommend to put at least 2 or 3 N.m
The next challenge for @Solarfun4jim with that flanged grub screw with the larger threads on top is how to get enough torque without exceeding the rating of the terminal top.
According to the table on post #2096 the torque for a 8mm thread is 10Nm and the terminal top is not to be twisted with more than 8Nm of torque. With a buss bar taking some torsion it might not be a problem but on a single positive or negative terminal, one might need to hold the main power lug to keep the terminal from rotating with that amount of torque.
 
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The next challenge for @Solarfun4jim with that flanged grub nut with the larger threads on top is how to get enough torque without exceeding the rating of the terminal top.
According to the table on post #2096 the torque for a 8mm thread is 10Nm and the terminal top is not to be twisted with more than 8Nm of torque. With a buss bar taking some torsion it might not be a problem but on a single positive or negative terminal, one might need to hold the main power lug to keep the terminal from rotating with that amount of torque.
Oh joy Ampster...lol. I think i'm spending more on tools than i did on the cells themselves.... :ROFLMAO::ROFLMAO::ROFLMAO::ROFLMAO:
 
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