Provide power for 2 or 3 PIs over small usb hub (12V version)

Hello!
Thanks for sharing your project!
Is it feasible to provide your 12V version ups to a small usb hub (e.g. 4 ports), providing power to 2 or 3 devices, when one exchange the five 10F (á 2.7V) with, let say five 50F (á 2.7V, the one you used for the 5V ups)?

Of course the charge at the beginning would take longer ...

Thanks and kind regards!