How Alkaline Batteries Are Made:
- While the alkaline battery's cathode is on the battery's outside, it is actually produced first. The material used to make the cathode is primarily a mixture of manganese dioxide and an electrolyte called potassium hydroxide--as opposed to ammonium chloride or zinc chloride in other batteries--along with graphite. These materials ground up into granules, mixed together, aged and compacted into a circular hollow tablet. A single battery usually uses three of these tablets, which are inserted into a steel can. The can and tablets combine to make the cathode. Sealant is placed near the top of the can to prevent the battery from leaking.
- To prevent the cathode and anode from touching one another, a small sheet of paper is rolled up and inserted inside the cathode. This paper is soaked in electrolyte to promote electrolyte conductivity when using the battery. The anode for alkaline batteries is a gel made up mostly of zinc powder. This gel is poured into the can within the paper that borders the inside of the cathode.
- While the battery is now functional, it must be sealed to preserve its shelf life. The primary seal is at the bottom of the can. This seal is made of a brass nail, plastic gasket, steel washer and metal cap. These parts are assembled to look like a nail with a very large head, which is then placed within and on the cap. The nail is inserted inside the anode and is used as the current collector while the assembled cap on top of it acts as the seal. The battery then has a metal top welded on the other end which has a tip to act as its positive terminal.