By Jack Byrom – Updated March 24, 2022
The battery’s outer shell is a standardized steel housing that secures all internal parts. Inside this enclosure, the cathode material is molded against the inner wall, establishing the positive terminal.
The cathode is the electrode that attracts electrons once the circuit is closed, allowing current to flow. In alkaline cells, it is a composite of manganese dioxide and carbon (graphite), which is positioned at the top of the battery and becomes the + terminal.
Placed between the anode and cathode, the separator prevents direct contact while permitting ion exchange. It only allows the electrochemical reaction to proceed when the device is powered on and the circuit is completed.
The anode consists of powdered zinc. It is installed together with the electrolyte and collector into the container, after which the battery is sealed. Zinc serves as the source of electrons.
Alkaline batteries use a potassium hydroxide (KOH) solution. This electrolyte bathes the anode and facilitates the movement of ions and electrons, enabling the cell to generate voltage.
A brass pin, embedded in the center of the anode, gathers the current and connects to the negative terminal at the bottom of the battery.
