Wolf
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- Sep 25, 2018
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Started new thread100kwh-hunter said:@ Wolf,
The story of different ir makes sense.
But the low ir (high drain cells) can be easy used with high ir cells(low drain cells)
We use the cells at really low drain, so i think there is no issue/problem here.
The other way around, if i would use the average laptop cell in my power tools, things might get to go sparky.
I found cells in laptop batteries that where the same as in my hilti power tool batteries, yes the one you don't like....begins with a S.
So that can be done, high drain in laptop = low drain application; other way around, no go!
Our powerwalls are basically low drain applications.(mine is down to 150mah a cell and will get lower with extension).
Charging up is a different story, on this one you are correct.
Cloudy day, and then a fullsunon your 10kwh array....and no consumers used at that time, only charging!?!?
What do you think about those thoughts/hypotheses? about high and low drain cells mixed, suited for the application?
If i am wrong just say it, i am in the learning process also.
Thanks in advance.
My thoughts and theories on high VS low drain are still in an experimental stage. As I am also in the learning process.
That is why I built the 4 cell parallel charging and discharging analysis board.
I have run some test as shown in several threadshttps://secondlifestorage.com/t-Locating-Self-Discharging-Cell-s-in-Packs?pid=53594#pid53594 andhttps://secondlifestorage.com/t-Behaviour-of-cells-in-parallel?pid=53209#pid53209but here is one that is interesting.
I pulled 4 cells out of my tested pile that had very close mAh results somewhat different IR and close voltage. I let them sit for ~20min and let them get to know each other. As you can see there was some interaction between the cells. 2 of them stayed even and cell 1 discharging giving power to cell 3.
Now this is in the low milliamp stage I was doing nothing but just observing. Then when I hit the discharge button you can see a large difference in the milliamps the cells are giving up initially.
I will run further tests and investigations on dissimilar cells such as ICR INR etc at low amperage draws such as 250mA per cell which is my build goal and 150mA and 100mA per cell just to see what a low amperage draw does. I will of course also run a 1A draw and possibly a 2A draw per cell to see the difference.
Once done I should have some idea of what actually happens and whether or not a low amperage draw does or does not make much of a difference in a mixed high/low drain cell pack.
Wolf