Fully charged battery lasts approx 10-15 smoothies, depending on your smoothie recipe. For e.g. blending ice and other hard ingredients can discharge the battery faster.
Approximately 2 hours are needed to charge the battery with the USB type-C charger attached to the package (65W power) or more powerful charger of your own. 60W charger is the minimum supported by millo, so if you will use charger from your iPad, which is only 18W, millo base won't charge.