Microvox battery boxes always have a jack socket on them. If your mixer has a line input socket, you can use that with a jack-jack cable and phantom power will not be an issue (and as Microvox are quite high output, the lower sensitivity of the line input isn't a problem)

If you want to use an XLR mic cable, you have to solve the problem of how to connect that to the Microvox box. A DI box is the standard foolproof solution. A simple jack - XLRM cable will short pin 3 to ground and pin 2 with phantom power will be connected to the signal output on the Microvox box. I don't recall whether Microvox has a blocking capacitor to keep the DC out, but I seem to remember having some trouble with this arrangement - some phantom power supplies don't work well if you short the pins to ground. The 6k8 resistor limits the current to 8mA, but on some cheap mixers that's enough to make the power supply drop out of regulation and you get hum.

I have made several battery boxes for Microvox mics with DC-isolated and impedance-balanced XLR connectors on them. They work VERY well.