Batteries. What’s happening in there? What makes the ions move through the electrolyte?
In simple terms, ions move through the electrolyte in a battery due to a difference in electrical potential (voltage) between the anode and cathode.
- Chemical Reactions: At the anode, a chemical reaction releases ions and electrons. These ions want to move to the cathode where they can react and achieve a more stable state.
- Electric Potential Difference: This movement is driven by the difference in electric potential (voltage) between the anode and cathode. The anode is at a higher energy state compared to the cathode.
- Electrolyte: The electrolyte provides a pathway for ions to move from the anode to the cathode while keeping the electrons separate. The electrons travel through an external circuit, generating electric current.
…So the electrons are powering my clock, and the ions are moving from the anode to the cathode in the background – presumably for no benefit to me and my clock?
Yes, the electrons directly power the clock, but the movement of ions from the anode to the cathode is essential for the overall function of the battery.
- Maintaining Charge Balance: As electrons leave the anode and flow through your clock, positive ions are left behind. These positive ions need to move to the cathode to balance the charge and maintain the flow of electrons.
- Completing the Circuit: The movement of ions in the electrolyte completes the electrical circuit within the battery. Without this movement, the chemical reactions at the anode and cathode would stop, halting the flow of electrons and, consequently, the power to the clock.
- Sustaining Chemical Reactions: The continuous movement of ions enables ongoing chemical reactions at the electrodes. This process sustains the generation of electrons, which keeps the clock running.