BC660K commands in PSM mode

I am putting my BC660K modem to sleep using PSM for 12 hours to save battery. Each time I wake up I check the battery voltage. The problem is that with a steep battery drop off of a LIPO battery, The voltage could drop off to zero before it wakes up. Can you read the voltage if the modem is in PSM?

Sorry, BC660K does not support CDC monitoring and query