Build a Pocket-Sized Power Supply with Just One Battery

Every portable electronics project requires a different voltage level for operation. A microcontroller might need 3.3V or 5V to power up, while LEDs, motors, and sensors all have their own requirements. When working in a home lab, supplying these different voltage levels is no problem, but in the field, carrying around a bulky power supply is a pain. There has to be a better way to power portable devices.

There are, of course, better options, and 5M WORKSHOP has just demonstrated a particularly interesting DIY solution. 5M WORKSHOP has turned a single 3.7V 18650 rechargeable battery into a pint-sized power supply that can output anything from 3.7V to 28V. The additional hardware only slightly increases the size of the battery, and it is still easily pocketable. Tossing a few of these mini power supplies into a bag to carry with you could save you a lot of trouble in the future.

The build is very simple. A TP4056 battery charging module and an MT3608 boost converter were attached to the 18650 battery with double-sided tape. Next, a mini digital voltmeter and rocker switch were similarly affixed to the battery. Once the circuit was wired up, the rocker switch could be used to turn the power supply on and off. A potentiometer on the boost converter adjusts the output voltage level, and the voltmeter displays the current setting.

It really couldn’t be much simpler to make, yet this is something that will serve you well for years. After all, every single project you make needs power! To see exactly how the circuit is wired up, check out the video below.