1) Remove four screw on each corner

2) Remove four screw on back cover corner

2) Remove rubber handle and remove two screw on each back side and three vinyl cover and screw

3) Remove SD card and open case carefully

4) Remove four screw on motherboard

5) Remove motherboard

6) Battery pack attaching on motherboard on other side, disconnect wire

7) Remove new battery pack and connect wire

8) Screw motherboard and outside case total 14 screw.