Batteries create a potential difference between their terminals through electrochemical reactions that involve the movement of electrons. These reactions occur within the battery's electrolyte and electrodes, leading to a buildup of charge at the terminals. The potential difference, or voltage, is a result of this charge separation, allowing current to flow when the terminals are connected in a circuit. The discussion emphasizes the importance of understanding these fundamental principles to grasp how batteries function. Overall, the potential difference is crucial for powering electronic devices.