Cool picture of the interior parts of a CR2032 battery:
Disassembled CR2032 battery From left — negative cup from inner side with layer of lithium (oxidized in air), separator (porous material), cathode (manganese dioxide), metal grid — current collector, metal casing (+) (damaged while opening the cell), on the bottom is plastic insulation ring
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.