If you have a power bank laying around and would like to use it as a means to power a robot car or any other electronics project, here is how to do it. The idea is to replace the battery box with a power bank. The current battery box uses eight 1.5 V AA batteries that produce a total of 12 V.

The robot car uses the GoPiGo board which operates with voltages between 7 V and 12 V. The Raspberry Pi needs 3.3 V to operate, while each motors need between 3 V and 6 V to operate at maximum load.
A typical 4000 mAh power bank outputs around 5 V, which is far too little voltage to operate the robot car. In order to power the robot car using a power bank I figured I would need a power bank that could output at a least 12 V.

Problem is that power banks with high voltage output are far too big to mount on a small robot car. Just as I was about to give up the idea of using a power bank to power the robot car, I thought of using a USB power converter.
I forgot all about a USB power converter I had laying around to use for powering externally my Sony Alpha camera with a power bank.
The USB power converter basically converts the power bank's 5 V into 8.4 V so I figure why not use it to power the robot car? All I needed to do now is get a DC plug converter and a DC connector extension that would connect the USB power converter to the robot car.