I like LiFePO4 batteries. They have a rather flat discharge at around 3.2V, which is ideal for powering 3.3V devices without a regulator. You can also use them in devices that take 2 standard AA cells by using a blank shunt in the 2nd battery slot since 2 fresh alkaline cells in series provide 3.2-3.3V. And since they are readily available in the 14x50mm AA size, you can use cheap AA holders for them in electronics projects.
When it comes to chargers, things can be a bit problematic. LiFePO4 batteries should be charged to 3.6V, rather than 4.2V like regular lithium-ion batteries. A good charger costs $10-$15, but charging at a high current will reduce the number of recharge cycles. The Soshine batteries I bought indicate on the label a standard charging current of 300mA to 3.6V. Rather than search for a charger to fit the bill, I decided to make one.
Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.