How to add Capacitors to Raspberry Pi

[Bernard]

Good day, all
I want to add capacitors to the Raspberry Pi power-supply.
Currently I have my raspberry Pi plugged straight into a portable 5v battery, this works fine. However, I want to be able to swap from one battery to another battery (via a switch) without the Raspberry Pi turning off. I figured the easiest way to do this is with supercapacitors (after I do some researches and get the ideas from Electronic Supercapacitor Applications Guide.

I've added two 25F 2.5v supercapacitors in series as shown in the picture. However, when I do this, the raspberry pi powers on for about 10 seconds (both red and green lights come on) but then it shuts down.

Is there anyone have ideas of it? Many thanks.

[AjayB_76]

Hi, 

The reason could be that the capacitors are placed in the negative terminal of the battery. Can you connect them in parallel and connect to the positive terminal of the battery and try the experiment. 

My theory on why this is happening: 

The capacitor acts like an open circuit in the long run for DC voltage. The ground terminal will be floating which causes the RPi to turn off.