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diy solar

Our NEW GO-TO LiFePO4 vendor...09.20.21

After nearly two months of waiting, my 302 Ah CATL cells showed up today:

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Apparently the CATL are indeed more prone to bloat than the EVE.
 
My EVEs had some bloating until I put them in a restraining fixture and flattened most of it. I think they will be fine.
did you squeeze them flat all at once, or gradually/stepwise? I've read that they tend to swell more at higher states of charge and that bringing them to a low state of charge may help them to reassume their original shape and allow assembly
 
did you squeeze them flat all at once, or gradually/stepwise? I've read that they tend to swell more at higher states of charge and that bringing them to a low state of charge may help them to reassume their original shape and allow assembly
I just used plywood on the ends and threaded rods. I torqued them to about 5 inch lbs at 3.3V then charged them to 3.4V and re torqued to 10 inch lbs. Cycle them a few times and re torque to 10 inch lbs when you get to about 3.4V. They will flatten out some but you will still be able to tell which ones were bloated the most.
Mine weren't as bad as yours and you probably should ask for replacements.
fhorst had more going on then just bloated cells. I suspect he had bad connections probably from dumping thread locker all over the place.
 
Just wanted to update the new URL for DONCAN for their US side of the house ... THIS is the URL that you want to use ... 3 months now and we have not had a single issue. Also as many of you have also tested - virtually everyone of their cells tested higher (0-6Ah) higher than the 280 rating. Yes I know that for the first 3-4 complete cycles most batteries always seem to push out more amps but so far - after a few hundred batteries - zero issues with the DONCAN folks at all ...

Still our GO-TO people ...

 
Just wanted to update the new URL for DONCAN for their US side of the house ... THIS is the URL that you want to use ... 3 months now and we have not had a single issue. Also as many of you have also tested - virtually everyone of their cells tested higher (0-6Ah) higher than the 280 rating. Yes I know that for the first 3-4 complete cycles most batteries always seem to push out more amps but so far - after a few hundred batteries - zero issues with the DONCAN folks at all ...

Still our GO-TO people ...


Are these 280N or 280K models? BTW, I couldn't find any info on which are preferrable on forum search. N models are presumably better as they are later iteration?

The link also lists 304AH model for the same price (see pic). Not clear if they are EVE or CATL.

Jenny, could you clarify?

Thanks.
 

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I will send you a PM. Thanks.

Jenny -- Actually allot of ppl (people) probably have the same question he does. Me personally I don't get so wrapped up in stud vs flat ...

Yes I know @Off-Grid-Garage and the YouTube channel RAY-BUILDS-COOL-Stuff will take hours of fine polishing and smoothing and caressing and reading poetry to these connector tops to getthe very very best connection --BUT honestly - I hit all of our tops for a few secs to get the oxidation off with a little fine grit polisher on a Milwaukee drill - use nothing but true copper as a connector cable - and make sure that I use self holding nuts and tighten per the manufacturers suggestion -- and then walk away ... about every 6 months I go and check the torques (ft/lbs) just to make sure they haven't vibrated loose ...

Not saying Off Grid and Rayu and the other 11,283 ppl that do this is wrong - and YES -- if you watch the RAY BUILDS COOL STUFF video he does that on some of the batteries the IR went from 27 to 17 -- but to me -- I'm ok with 27 (+/-)

On a much more important note though - Yesterday it was 78F out here -- this morning stepped outside the trailer to go to work and it was 45 with a hi of 50 .... WTH !!??!!
 
Are these 280N or 280K models? BTW, I couldn't find any info on which are preferrable on forum search. N models are presumably better as they are later iteration?

The link also lists 304AH model for the same price (see pic). Not clear if they are EVE or CATL.

Jenny, could you clarify?

Thanks.
Mine are for an RV and in side by side testing have only had success with the weld on studs as compared to random failure with screw in (on quality 200ah cells purchased from prior to learning about Jenny Wu / Docan). I do believe the screw in failure is directly related to the number of times you are interacting with the cell bolts. Heliciols helped a lot but after putting in 16 on 8 cells i'm never going through that again. They weld on just work all the time without issue.
 
Best experience ever, picked up at Houston location and could not be happier, 302ah 51.2v awesomeness, THANKYOU AMY, nw upto 1002ah, Joe.
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My 1st 18 - 12.8v Lifepo4 Batteries (2 spare) from E-on have the cells laying on their side when standing up, Signature Solar confirmed it was ok to lay Gyll batteries on their side, and Amy confirmed it was ok to lay Calt 302ah cells on their side, it was enough for me and it's been working fine, Joe.
 
Mine are for an RV and in side by side testing have only had success with the weld on studs as compared to random failure with screw in (on quality 200ah cells purchased from prior to learning about Jenny Wu / Docan). I do believe the screw in failure is directly related to the number of times you are interacting with the cell bolts.
That is some valuable experience. Loosening and tightening the nuts over and over is likely to cause stud failure. Your cells are also more likely to shift around in your RV than they would sitting on a self in a stationary setting. The aluminum that the studs screw into is soft.
Heliciols helped a lot but after putting in 16 on 8 cells i'm never going through that again. They weld on just work all the time without issue.
I used a helicoil on one terminal after I stripped the threads. Then I started using loctite. I am happy with mine but if I was to buy more cells, I would check into the welded studs.

There is one issue with loctite or welded studs that I haven't resolved. It is difficult to clean the terminals with the studs in the way. Unclean terminals is a serious problem.
 
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There is one issue with loctite or welded studs that I haven't resolved. It is difficult to clean the terminals with the studs in the way. Unclean terminals is a serious problem.
During my screw in stud repair I used the products recommended in another users youtube video. 1000 grit sandpaper on the round "puc like pad" along with Deoxit. Again beating a dead horse here - way more time, cost and unpredictable behavior vs. my weld on studs so i am waiting patiently for 16 new LF280K's from the incredible @Jenny Wu
 
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I work on high end German cars and have for 40 years. At no time did any of the manufactures recommend to check the torque on the electrical connections every 6 months. High or low load circuits. Connections should be a set and forget. If you are having problems, then you have a design problem.

There is a design flaw if you have to maintain the torque every 6 months.
 
Hi Ghostwriter-
I think I got to the same place you are. In my last video on the subject, I hit the tops for a few seconds with 400 grit on a nifty little attachment on my drill. I really try to get the effort down to the minimum. I suspect you also use an anticorrosion agent on the aluminum, right? What am I doing that you aren't, other than the reading poetry to the terminals part?

38 here this morning. Still no freeze this year which is kind of scary. Last year's icepocalyppse killed off all the bugs but this is going to make for an armageddon of bugs next year if we don't get some cold weather. Am I really hoping for cold weather?

Anyway, here is what I'm doing now. It gets lots of comments and some of them say I don't go far enough. To me, safety is all about the connections and your torque check every 6 months should be on everybody's list as tedious as it might be. I'm guessing the people that don't change their AC filter won't be bothered to do it though. Cheers

Thanks for the video Ray. Someone recommended the dowel like you have but I had trouble getting the sandpaper to stay on.
Now that I watched your video I will make it work like you did.
 
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There is absolutely nothing wrong with your approach. If you sleep better knowing that things are right, that is what life is about. People get too concerned about what others think.
 
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