I don't understand why certain sellers like to keep their price a secret. Other places publish their prices and shipping details so buyers can compare.
It's normal in China, and many other countries, for business to be done by negotiation or through a certain price on volume. If someone gets a better deal, they don't want the customer that didn't get the better deal to know about it. I think it all comes together the same way for high volume transactions as well because the little guy buying 50 cells at 60Ah won't get far trying to buy at the same price as 100,000 cells at 200Ah, for example.
India is similar to this as well. I used to work in Minneapolis(work in the suburbs now, where parking is free) and would visit a store that sold electronics nearby from time to time and it wasn't uncommon for a man from India who is working in the US to come up and be excited while he tries to haggle a deal on 5 digital cameras to send home to his family at a big store that has fixed prices. In India, China, and many other countries, they are not direct with purchases and do not have fixed prices because they sell things market-style where deals are made.
If all my cells are rated at like 110 and all fall within that 110 range + or - a few AH's and I put in 100 AH then That is all they will have in them. They won't have more than what I put in. If I have a glass that can hold 110 ounces and I only put in 100 then 100 is what I get out. They will always hold that if my filler container can only hold 100 ounces. I fill up each cell to 100 and that is all each will give. I just have some spare room. So it won't matter if a cell can hold extra cause your not using it, right?
As far as capacity goes, that is correct, it won't matter because they will drain down at the same rate but if you have one that has a capacity of 110 when fully charged and one that is 100, when you draw them down and you are pulling, say 300 amps, you draw 3C from a 100Ah cell and 2.7C from the 110Ah cell. The 100Ah cell will generate slightly more heat which is wasted energy and slowly over time that wasted energy adds up to imbalance. The bigger the capacity difference or impedance mismatch with a pack, the bigger difference it makes. Of course usually you don't draw constantly at a high rate to where the cells get hot so its not as big of a deal as you might initially think but its a factor. If you had a bigger disparity amongst the pack, it would require a little more attention every xx cycles. This is the primary source of lithium cell drift, there isn't much of it, but its there, energy lost at heat with different rates between cells.
No, the smaller cell will last the normal time and the others will just last longer. The higher one can't affect the lower on at all. The life of the low cell is the life of the group. It sounds like your saying that the cell with more capacity will cause the lower capacity cell to actually age faster than normal. If you set your pack up to operate within the factory specs then it will last as the factory states. Might even last longer. But the one with more capacity can't make that low cell actually age faster.
"The life of the low cell is the life of the group."
No, it's not. If the first cell in the pack reaches end of life for whatever reason, remove it or bypass the cell, adjust the charging voltage and keep driving because the rest of the group is going to be fine once the first cell fails. You will lose the capacity of that one cell and have a slightly lower pack voltage but if it was your lowest capacity cell and the next lowest capacity cell is a bit better than this one was, it might not be so bad. 100Ah cell is only going to be 320wh anyway, so a mile or mile and a half or so depending on the efficiency of the conversion.
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