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Ah! Came up with a new mounting method. They are cheap and called screen door clips!

I've got decades of power electronics experience, including power inverters, battery chargers, and BMS's. Let me know if you or anyone want to collaborate on an open source BMS. I've reviewed what is currently available on-line and github, and JK is years ahead. But it's not perfect and it's not...

I'm working on packaging and BMS solutions for cylindrical cells, of all lithium types. Current product on eBay has 18650 (working on 2170) cell packaging with and without JK active balancing BMS. All packages are bring-your-own cells. System uses high current gold plated Beryllium Copper...

Not using LFP, but we have problems with cyclindrical cell packaging too. I've tried tape, tie-wraps, and blue tape. Best solution so far is to hang angle brackets off and screw to the battery blocks...I've also used 3M double backed tape. My request to JK is to give us some mounting tabs times...

Thanks JMack! I'm working on 2170 cell type next, but I'd like to package larger cells too. If you know of any larger cells, I'd love to hear how you would package them, in what parallel grouping would you do? I'd look at the 4680 type but I don't think there will be a lot of salvage cells...

And you can calibrate the current the same way.

Thanks Tom, maybe take some numbers down? What the cells resistance are with no load and some normal connected load, over time? I've got an 8S lithium ion bank I can cycle 100% of capacity daily for a year. That might give some usable data. Yours would have to be over a longer time to make a...

Ok I see a lot of views on the subject, so maybe I should start it off with an example from the JK BMS I'm testing. On the main screen of the Bluetooth app you get a reading of the "Cells Wire Resistance" along with the cell voltages... To calculate this value, the JK BMS turns on it's...

Has anybody seen studies of what the curve of internal cell resistance looks like over the life of a Lithium Ion and Lithium Iron Phosphate (LFP) cell? According to most papers I'm reading, the end of life comes at 80% of initial capacity value, or internal resistance of 200% of initial value...

Quick thought, of course we are trying to pin all the variables to the same value. I.E. Temperature and state of charge are variables, but for the sake of the argument, we will hold those to the same values, i.e. 65F and 90%. t

Do you have a Manufacturers part number or link to that part? Is a super cap really necessary? How many cycles are super caps rated for? it would be interesting to do the math to see how much energy we are talking. If the energy in a cap is = 1/2CV^2, and the cap is say 2F (I have no idea what...