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Im very sure that the BMS's Im using are are charging and discharging correctly. The reason why my packs are not working correctly and failing is because Im setting up the system to abuse the components rather than use them the way they are supposed to be utilized.

I do see what you are saying. I guess my response is that manufacturer's of LiFePo4 battery packs that are composed of 18650 batteries are using 1 BMS for the whole pack. They are ALL doing that. None of them are using 7 BMS's for each cell of those series. I am using better BMS's than most...

Ok, just bought 2 of them (as you described). My next question is that I saw on another thread ( https://diysolarforum.com/threads/lifepo4-cells-on-48v-system-charging-faster-than-others.19612/ ) that one should "Top Balance" the cells. Soooo what do I need to do that correctly with the 16 x...

You didnt list the Make/Model of the 10a PS you are using - may I ask which one that is?

I have built SEVERAL 3S7P 18650 battery packs, mostly for a pair of APC UPS's. I buy the battery boxes as a kit from Ali Express. The kits themselves are decent and the materials are pretty good. They can come with a 20A (or so) BMS. I put together around 30 of these about 12-18 months ago where...

Looking at another forum ( https://diysolarforum.com/threads/top-balance.22562/ ) I REALLY liked the Riden I saw in a picture Gazoo posted. His looked like a RD6012 ( ? ) - its hard to tell with the picture zoomed in. Anywho - I just bought this...

So BMS's are on order (check) and the Power Supply is also on order (check). Anything else I need to get this party started?

I have Heat Shrink tubing (probably could use more because I see where you are going with this). I have a Heat Gun. Crimping Tools - Id love suggestions on what you have/prefer? Small Ring Terminals to fit the balance leads (I ll get these when I go to Home Depot). Torque Wrench that can...

I >VERY< much appreciate the feedback/response! I wasnt sure what anyone would say let alone actual feedback. A) The APC UPS's Im using are ones that have very quality hardware involved. Charging and Discharging are very much within what is to be expected, meaning over a couple months of...

I just saw this post and am VERY interested in anyones feedback regarding a LiFePO4 battery pack in a standard (Data Center quality) APC UPS. I recently made my post regarding my "issues": https://diysolarforum.com/threads/3s7p-18650-battery-packs.73937/ .Roughly 3 years ago I started "looking...

This post shows structurally what I built. https://diysolarforum.com/threads/3s7p-18650-in-nice-little-box.14432/ There's several Youtube videos on these battery packs. To answer your question, I believe the nomenclature is that the number preceding the S is the number of strings, and the...

Well, Im by no means the author of the nomenclature. I am simply stating this as I understand it, but in pretty much every post I have ever read, this is the way the authors of those posts are describing their battery design/structure. Further, in other forums that sell components this is also...

Yes, well stated. If you were to purchase an APC UPS from APC which includes batteries, Im pretty sure that there's no option for LiFePO4 batteries, which is why I started this project 3 years ago. Why not? They should out perform FLA (FLA = Lead Acid batteries?) batteries in every way. The...

I was going to "argue" that what you said is not accurate. That 18650 batteries are not 3.2v, and are in actuality 4v+ which is why you can make a 3S battery using them for a 12v pack, BUT this just may be a dynamic of the 18650 that is "abused". If an 18650 is properly used, it should not be...

The wiring inside any UPS is pretty much set for 20amps (or less) per battery, meaning Im seeing 10ga wire inside the UPS. You can "get away with" 12ga, but 10ga is pretty standard for 20a. Im positive that overload is not the issue as these batteries were not overloaded. I am pretty sure...

I dont follow. Check my BMS settings for what? How much Amperage? Whether the BMS is 3S? In either of those cases its been validated on what it can do.

I purchased (and recently received) 16 x 3.2v 320Ah cells. I'm building a 21KW (probably bigger...) solar array and the storage system I am going to go with would be 2 sets of 16 x 3.2v 320Ah cells. I want 2 x 48v 5Kah banks in parallel. Where I am at now is I need a BMS for both (if possible)...

Ok, but I was addressing your previous comment about using 7 BMS's on a 7P battery pack (effectively making it 7x 3S1P in Parallel), when manufacturer's are not doing that. You were saying that I should have a BMS for each Cell in a Series or 7 BMS's and I am saying that I dont think thats...