The advent of USB-C and the power delivery (PD) standard have allowed for a single cable to carry both large amounts of data and power for a wide range of devices. So, while looking for a PD-capable power bank for his laptop but only coming across expensive units, Instructables user Toby Chui decided to make his own — with additional improvements, of course.

The design for this custom power bank started with a basic schematic consisting of the LiPo battery, a 60W PD module for handling the negotiations between the board and whatever device might be on the other end, and a display unit for showing current battery information. After soldering together a small piece of perfboard containing a buck converter, voltage divider for voltage measurements, and an ACS712 current sensor, Chui glued the entire assembly onto the back of a UART HMI display. 

The last component was an Arduino Nano that takes in voltage/current readings and sends them to the display, along with the current voltage being delivered over the USB-C cable and the total power consumption. With the electronics finished, Chui modeled and 3D-printed a small case that holds the battery and switch at the base while the screen at the top displays the information. You can read more about this project here on Instructables.