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Is it possible to put Lipo/Li-ion batteries of different capacities in parallel?

I am aware that putting anything different in series/parallel isn't the best option, but design limitations do not allow me to do otherwise.

What other limitations should I take in account?

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    \$\begingroup\$ It could accelerate failure. You lose control over charge and discharge current of the individual cells (you don't know how they share charge current). I would say that the slower you charge and discharge the cells, the more likely it is to work out OK. Also, you want the series resistance to be inversely proportional to the capacity of the cell. \$\endgroup\$ – mkeith Oct 8 '17 at 17:59
  • \$\begingroup\$ If the cells are brand new, and came from the same factory using the same manufacturing methods, same electrode materials, and same electrolyte, then it is probably fine. \$\endgroup\$ – mkeith Oct 10 '17 at 2:59
  • \$\begingroup\$ @mkeith they aren't from the same factory / capacity / age \$\endgroup\$ – AltHaoX Oct 10 '17 at 4:13
  • \$\begingroup\$ Well, I know they are not the same capacity. That is the main premise of the question. Not the same age, either. That is not a design limitation. You could buy new cells. If you mix old and new cells, that is not due to design, that is due to budget constraints or something else. At a minimum, mixing old and new cells is not a great idea because it is very likely that the back lifetime will be limited by the life of the oldest cell. \$\endgroup\$ – mkeith Oct 10 '17 at 4:23
  • \$\begingroup\$ @mkeith so, i changed the design: i made 5 groups of batteries that share approximately same capacity. this should help, right? \$\endgroup\$ – AltHaoX Oct 10 '17 at 4:59

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