The voltage (or electric potential) of battery determines

a. how much net electric charge is in the battery

b. how much work the battery can do on an electric charge

c. how much electric field is around

I am pretty sure that the the voltage (or electric potential) of battery determines b. how much work the battery can do on an electric charge. According to the fact that volts include such units as jules and colombs, it means that it depends on work and electrical charge. Hope it's clear.

Regards!