What strength and in what direction does the current flow between the batteries connected in series?

Question

Rechargeable batteries

Let's say that we have 3 consecutive li-ion cells in the circuit, the load is supplied with a current of 5A, a voltage of 12V.

And what happens if you add another load to the circuit, say between cells 1 and 2?

Answer 1

Am I right if I say that in all sections of the circuit the current will go counterclockwise (from plus to minus), and the current strength between cell 1 and 2 will also be 5A, as well as between cells 2 and 3?

Yes, in all parts of the circuit, the current flows in the same direction and the current strength is the same. If there were branches in the circuit (parallel connections), then in these sections the current would be less; but there are no branches here, so if on some section 5A, then on any other section 5A.

what happens if another load is added to the circuit, say between cells 1 and 2?

the load has some resistance greater than zero, this additional resistance reduces the current in the circuit. How much it reduces depends on the resistance. Maybe the current will be 4.99A, or maybe 0.01A, but the current will again be the same in all sections.
To determine the voltage at the new load, you need to know the resistance of both loads and the internal resistance of the cells.

Answer 2

4 volts