It’s always great to find a new episode of Collin’s Lab in my YouTube queue. In this episode of the series from Adafruit, Collin offers a brief, but informative introduction to battery tech. In under eight minutes, he manages to cover the various battery form factors (e.g. did you know the common 9v battery is actually called a PP3?), basic battery specs, chemical formulations, and the strengths and weaknesses of the various battery types.

Did you also know that a common 9v battery in that PP3 package is not actually a single alkaline cell? Take one apart and inside you’ll find six small cylindrical battery cells providing 1.5v each. These six cells are wired in series to deliver the PP3’s 9 volts. And, as Collin points out, because the terminals on a 9v are so close together, you can “test” them by placing the terminals on your tongue. He does this. It’s unpleasant. Don’t do this.


I’ve always been a big fan of Collin’s videos, from back in the day when he used to produced them for Make:, to his current work with Adafruit. I am not alone. The YouTube comments section always shows how popular Collin and Collin’s Lab are. I love this comment from the battery video:

Collin has a way of really breaking it down while making me feel groovy at the same time. Thanks, Collin! Nobody helps me learn more about electronics projects and electrical engineering pertinent theory than you do!

I couldn’t agree more. Also, check out Collin’s “History of the Battery” video for more on the development of battery technology and how batteries actually work.