Moto C has 2350 mAh removable battery.
Yes, Motorola Moto C comes with Android 7.0 Nougat OS out-of-the box.
Yes, you can expand the memory by up to 32GB with the help of MicroSD card.
No. You can use only one sim card on 4G mode in this phone. You need to use 4G sim card in sim card slot one. Second slot shall use 2G sim card.