Though we may group them all under the single term “batteries,” there are actually some 35 different types based on combinations of materials alone. If we factor in different shapes and sizes, then there are around 4,000 different kinds of battery.
Batteries can be broadly divided into two main categories depending on how they generate electricity and the materials used to make them.
One is “chemical batteries” which generate electricity through chemical reactions between metallic compounds and such like. Another is “physical batteries” which generate electricity through solar or thermal energy. Let’s look at “chemical batteries” here.
Chemical batteries consist of two poles – positive (+) and negative (-) – and an electrolyte solution. Chemical reactions between the poles and this solution are what generate the electricity. So by using different substances for the poles and different electrolyte solutions, we can make lots of types of batteries with different properties and voltages.
“Chemical batteries” can be further divided into two main types. The batteries we usually call “dry batteries” – the ones whose energy will eventually run out after prolonged use – are properly known as “primary batteries.” Then, we have those which unlike “primary batteries” can be recharged and used again after they run out. These rechargeable batteries are properly known as “secondary batteries”. We use these two different types of batteries for different purposes in our everyday lives.
Below is a simple illustration summarizing everything we have learned so far. These are the main types of different batteries.
Reference: Battery Association of Japan. The image is based on the association's Battery Type page (note: Japanese language only.)