Sony SRS-XB10 is a mono speaker. However, you can use 2 SRS-XB10 at the same time with your device and they can perform as a stereo speaker.
No. Sony SRS-XB10 does not have the inbuilt FM radio but you can attach it to your phone via Aux cable and can play FM radio via your phone.
Sony SRS-XB10 has 1400 mAh Li-Polymer battery.
Sony SRS-XB10 has 5W sound output capacity.