Three Battery/Cell Types

Last summer I tried my hand at building a drone. I learned a lot about drone battery use, and eventually settled on a 14.8V (4*3.7V), 4000mAh Lithium Polymer (LiPo) battery with a 10C rating

In my last job we occasionally would use the lead acid batteries you can get at most hardware stores. The standard size we used was 12V, 7Ah, C5 capacity.

I also often use CR2023 coin cell batteries that provide 3V and around .2 mAh. I’m not sure of the C rating.

Powering an LED (round 3)

Last semester I got really into powering my fabrication projects with human power. This in turn built off a project I made a year or so ago, a hand cranked LED sign. All of these were kind of hacked together, so I look forward to approaching energy generation in a more formal context for this class.

The projects mentioned above all use DC motors to generate power, so for this week’s assignment I asked the group if we could experiment with stepper motors instead.

It wasn’t difficult at all to plug in an LED to a 5V stepper and get it to turn on. The really surprising thing was that is didn’t seem to matter not only which direction you wired the LED (which makes sense as the stepper current alternates), but even which wires you plug it into. That was very surprising to me, I look forward to discussing how that happens more in class.