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Battery Harvesting process
#1
Hi I'm new and been reading all the great guides written by the people here. I'm curious about the process that most people use for harvesting batteries. They all more or less doing the same process of charging fully and discharging to get the capacity. Another full charge and leaving them for 30 day or more to see if there is drop in voltage.
I'm wondering if you have to do them in that order? I was thinking of charging them full and leaving them for 30 day first. After find out which battery didn't have any voltage drop, I would do the capacity test. Wouldn't I save more time if that did it that order as I don't have do capacity test for those battery with voltage drop?

Thanks

Yoshi
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#2
Either way is fine. I think whether one saves time will depend on the failure type and failure rate of the cells. If you have high percentage of self discharging cells, you might want to do that test first. If you have a lot of worn cells with little capacity left, do that test first. If almost all your cells are good quality cells, both ways will take equally long.

It'll probably also depend on the whole workflow. For me, it's easier to do the SD check last, just as I'm putting the cell to my packs.
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#3
This is the answer to your question
Depending on what type of charger/testers you have.

Your way:
1. Charge them up
2. Test for voltage drop
3. Test in capacity tester

I do it this way with the opus
1. Charge them up, capacitty test and then let them sit
2. Check for voltage drop

As you can see the 2nd one have less manual work from my side into it. An for me thats the costly part in collecting and sorting the cells. For other the time in the tester is the problem but with enough testers thats not an issue.

I recommend that way.
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#4
(10-27-2019, 06:42 AM)daromer Wrote: I do it this way with the opus
1. Charge them up, capacitty test and then let them sit
2. Check for voltage drop

As you can see the 2nd one have less manual work from my side into it. An for me thats the costly part in collecting and sorting the cells. For other the time in the tester is the problem but with enough testers thats not an issue.

I recommend that way.
And #1 will reveal heaters (for discard) sooner so you don't waste time on them.
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#5
But wasting time depends. You charge them up neither less if you run test 1 or 2. But the thing is going with the cycle test directly is the one that firstly do a full charge. And its not untill then you get the true result of a cycle Tongue

But as said a simple iR test do reveal alot of information so doing that as first test can save you time too in the tester.
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#6
I sometimes use the second option if I have a lot of cells that I don't want to cap-test at the harvest moment.
i charge them all, let them there, measure all of them when I have time for V-drop and then priority cap-test the best ones, letting the others for later.
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