100 Ah and 200Ah LiFePo in parallel- why twice the current?

doenertier12doenertier12 Registered Users, Users Awaiting Email Confirmation Posts: 1
edited June 11 in New Battery Technologies #1

If I connect 2 Batteries in parallel, one with 100Ah and one with 200Ah, why does the 200Ah charge and discharge  with twice the current, if they have nearly the same internal resistance? I thought the internal resistance was the only current limiting factor. If the 100Ah would have an internal resistance of half the size it would make sense to me but it has nearly the same. I thought maybe the 200Ah needs twice the electrons in order to reach the same voltage but I am not sure if this is the right explanation.


  • mcgivormcgivor Solar Expert Posts: 3,020 ✭✭✭✭✭
    The internal resistance is governed by the electrolyte space between the plates, both of which would be the same.The surface area of the plates however would be double in the 200Ah cell, so it has the ability to move more electrons.
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