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Parallel-serial-parallel common?
Interesting. Any other voices on that. I already wrote my opinion on that.
In your example, 60ah, 60ah, 30ah…

You will just have packs moving around equalization current during discharge. No different than cells in a larger pack.

And just like induvial cells, IR matters in high discharge applications. No different here.
Maniac it Will work fine and yes the lower capacity pack Will deliver less current. Thats the basis of ohms law
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As Daromer said, you can generally parallel connect multiple batteries of different capacities without much issue.

Though you have to be aware that on (dis-)charge, the Amps will not split evenly.
Say you connect in parallel Battery#A (90Ah) and Battery#B (10Ah) to have a combined 100Ah system.
When (dis)charging at 50Amps total, the current will split roughly #A = 45Amps and #B = 5Amps. And both #A and #B will discharge evenly in terms of Voltage / SoC%.
So you'll need to take that into consideration when fusing, wire thickness, etc.

Also, when (re)connecting a battery, you have to make sure that it has a similar voltage as the other batteries. Otherwise, too much current will flow trying the balance the charge, and you might pop fuses or overheat and damage cells.

My advice is to make all packs the same capacity. Makes management easier, and you can have just one spare pack you can pop in during maintenance.

Benefit 4) Smaller packs = easier to find faulty cells
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