Battery Type: Non-removable Li-ion Polymer Battery
Capacity: 2750 mAh, 3.8 V
Talk Time: Up to 14 hours on 3G
Standby Time: Up to 10 days (250 hours)
Internet Use Time: Up to 10 hours on 3G, up to 10 hours on LTE, up to 11 hours on WiFi
Music Listening Time: Up to 50 hours
Video Playback Time: Up to 11 hours

iPhone 6S Plus Battery