Why batteries come in so many sizes and shapes

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.

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