As far as I undertand the specs for this thing, there is only one USB power connector and no way for the user to choose the voltage. It seems to be the powercharge technology that through some kind of dialog between the charger and the device adjusts to a higher voltage (9 or 12 volt) when the battery is low and reduces it to near 5 volt when the charge is complete. When a non powercharge device is connected voltage seems to stay at 5 volt.
So if the Shure can live with 5 volt, it should work as it would with any other USB power source. If it requires more volts, it will probably not work (the Sound Devices MixPre-D would not).