How Alkaline Batteries Work

Batteries 101

All batteries work by creating electric current through the movement of charged particles between two electrodes, the cathode and anode. The differences between battery designs are in the specific electrochemistry used in a battery design: what the cathode, anode and the electrolyte medium in between them are made of will vary with particular battery types. However, the basic principles will not.

Electrochemistry

Most batteries that are called "alkaline" are zinc-manganese types. The anode/negative terminal is made of zinc powder. The cathode/positive terminal is made of manganese dioxide. The electrolyte is made of potassium hydroxide. The batteries are very similar to the zinc-carbon design but are an improvement in chemistry, because while they have a similar power output, they have three to five times the stamina.

Recharging

Some alkaline batteries can be recharged. This involves putting electricity into the battery, which reverses the chemical reaction between the anode and cathode, partially or completely restoring their ability to discharge electricity. However, most alkaline batteries cannot be recharged, because doing so causes their casings to rupture and leak dangerous potassium hydroxide.

Resources

• Circuitry for Rechargng Alkaline Batteries
• Alkaline Battery Disposal
• Alkaline Battery Data