batteries in series

Hello, I can't image what is the exact path of electrons in two or more batteries conncted in series... if electrodes are immersed into the electrolytes and chemical reactions should continously happen why the circuit in the picture down here has no activity ?

what prevents chemical reactions to happen since electrodes and electrolyte are in contact ?

When a load completes the circuit between the two terminals, the battery produces electricity through a series of electro-chemical reactions between the anode, cathode and electrolyte. The anode experiences an oxidation reaction in which two or more ions (electrically charged atoms or molecules) from the electrolyte combine with the anode, producing a compound and releasing one or more electrons. At the same time, the cathode goes through a reduction reaction in which the cathode substance, ions and free electrons also combine to form compounds. While this action may sound complicated, it's actually very simple: The reaction in the anode creates electrons, and the reaction in the cathode absorbs them. The net product is electricity. The battery will continue to produce electricity until one or both of the electrodes run out of the substance necessary for the reactions to occur.

Here is how the lead-acid battery in a car works:

The anode of each cell is metallic lead, Pb. The cathode is solid lead oxide, PbO2. The electrolyte is sulfuric acid, H2SO4 (which is dissociated into hydrogen (H+) ions and hydrogen sulfate (HSO4-) ions in solution.)

When electrons are allowed to flow (when the battery is under load) this reaction takes place at the anode (- side):

Lead metal is oxidized to bivalent Pb(II), giving up 2 electrons, and reacts with sulfate ion (SO42-) to form lead sulfate and a hydrogen ion:

Pb + SO4²¯ → PbSO4 + 2e- + H+

The reduction potential of this reaction is +0.356 Volts.
Simultaneously at the cathode (+ side):

The lead in lead oxide is reduced from tetravalent Pb(IV) to bivalent Pb(II) when the lead oxide reacts with sulfate ions in the electrolyte and hydrogen ions, accepting electrons to form lead sulfate and water:

PbO2 + SO4²¯ + 4 H+ + 2 e- → PbSO4 + H2O

The potential of this reaction is 1.685 volts.
Combined, these two half reactions make up the redox reaction

Pb + PbO2 + 2H2SO4 → 2 PbSO4 + 2 H2O

Two electrons were liberated at the anode and flowed through the external circuit to the cathode. The total potential of the reaction is about +2 volts. A 12-volt car battery therefore has six cells in series, each contributing two volts for a total electric potential of 12 volts.