The core of the work of the AA rechargeable battery is to achieve bidirectional conversion of electrical energy and chemical energy through electrochemical reversible reactions. When discharging, it releases electrical energy for equipment use, and when charging, external power inputs electrical energy to store chemical energy. The working principle of different types of AA rechargeable batteries (such as zinc nickel batteries, nickel hydrogen batteries, and lithium batteries that you are concerned about) is basically the same, only the materials used to store chemical energy are different.
All rechargeable batteries are composed of four core components: positive electrode, negative electrode, electrolyte, and separator. The working process is divided into two reversible stages: discharge and charge.
Discharge stage (external power supply)
Spontaneous oxidation-reduction reactions occur inside the battery: the negative electrode material loses electrons (oxidation reaction), and the electrons flow through the external circuit to the positive electrode, supplying power to the electrical equipment; The positive electrode material obtains electrons (reduction reaction), and ions in the electrolyte migrate between the positive and negative electrodes through the separator, maintaining the internal charge balance of the battery.
Charging stage (storing electrical energy)
The external power supply provides reverse voltage, forcing the battery to undergo a reverse reaction: the positive electrode material loses electrons, and the electrons flow through the external power supply to the negative electrode; The negative electrode material gains electrons, and the electrolyte ions migrate in reverse, converting electrical energy into chemical energy for storage until the battery returns to a fully charged state.
Compared to disposable batteries, rechargeable batteries can be reused through charging, which can greatly reduce material waste and will completely replace disposable batteries in the future.
