Power Raspi externally for long time

[kevin56789]

Hi,

I am trying to use my Raspi for a project in the city, but I am not sure how I can power my Pi for an extended period of time. I know that Pijuice exists, but it only powers the pi for 24 hours. I am looking for ways to construct a externally portable battery source for my Raspi.

Does anyone know anything about or tried combining batteries/Pijuice in parallel?

I really appreciate the help.

[W. H. Heydt]

How long do you need to power the Pi and what is going to be attached to the Pi that will need power?

To start with, approximate the power requirements of the Pi as 1A at 5v (=5W), Then figure out how many watt-hours of capacity you need. Then add some more for losses in voltage conversion, limits on battery discharge depth and such.