Why Do Batteries Have So Many Shapes and Sizes?
The answer involves a fascinating, brief history of technological innovation and market forces
By Wesley Chang, Assistant Professor of Mechanical Engineering and Mechanics, Drexel University
If you’ve looked in your utility drawer lately, you may have noticed the various shapes, sizes and types of batteries that power your electronic devices. First, there are the round, non-rechargeable button cells for your watches and small items. There’s also the popular AA and AAA cylindrical batteries for calculators, clocks and remotes. Then you have the rechargeable lithium-ion batteries in your laptops and phones. And don’t forget about the lead-acid battery in your car.
I’m a professor who studies batteries and electrochemistry. To understand why batteries come in many different sizes and shapes — and serve many purposes — look to the past, at how batteries originated and how they have developed over the years.
The first batteries were made in the 1800s, and they were quite simple. One of the first demonstrations was a series of metal discs soaked in brine, which Italian scientist Alessandro Volta found created an electric current. The first lead-acid battery was made of a few pieces of lead in a jar of sulfuric acid.
