Herbi said:
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I have the impression most of thetester that are used by people here,are way off, when it comes to cell capacity.
Further, some people dont even know there discharge current. They just put it in the tester.
I very much doubt, that a 4-way tester will discharge each of the four cells with 1A.
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I'm pretty comfortable with using Opus's to measure capacity. Despite their notorious 'inaccuracy'. Think of it like a meter rule, which does not measure exactly 1000mm. What does it really matter, when all we are really doing is gauging RELATIVE capacity. It doesn't -- at all! So long we know which are the duds, and the relative capacities of each cell to build semi-balanced capacity packs..
It's very hard NOT to notice the current of the Opus. When one inserts a cell to charge/test it changes the screen to display current. One has to actively change the display mode to get it off that readout ... me personally, I like to leave them sitting on the voltage display ... so I am forced to press a button to do this, only after the current is flashing on the screen. And yes, the Opus is a four way charger, which works at a max of 1000mA per slot. I really don't know why you would doubt this pretty mundane fact of life ...
OP: thanks for this poll, I too am interested in the possibilities of uses for my lower capacity cells. From the initial results, it looks like not too many voters would be interested in my lower capacity cells, but then ... I'm not really targeting that kind of folk ... I always expected it would be the tinkerers / noobs that might be interested in buying them.
All that said, I have very different standards depending on the packs Im building. EG 'temporary' or 'giveaway' packs I make, I choose the lower end. If I'm making something to be portable, EG to recharge my quadcopters in the field, I pick my absolute highest capacity, for energy density reasons (I'm carrying them all!).
And finally, I am starting to base my decisions for powerwall use based on what % of original (new) capacity remains ... IE I would now lean towards using a 1500mAh cell that was originally rated at 2200, over an 1800 that was made as a 3000. Totally made up numbers, but you get the idea ... its all relative.
PS the cells I use are ALL harvested, IE used. They are well into their lives. This means their capacity is changing ... I'm trying to find cells that will change as little as possible over time. This is more important to me (now) than their actual capacity.