Anyone use a battery pack with spectra?

Ellie 💙

I’ve been looking up ways to make my Spectra S2 battery powered, and I saw a blog where a lady used the Medela battery pack. Anyone try this? I would love to be able to pump on the go at times. I have a friend who pumps on her commute to and from work, and I think that’s genius! But with the S2, it’s only usable plugged in. I’m willing to fork out the money for an S1 if I have to, but didn’t know if you all who have an S2 had any suggestions?