To change the batteries, you will need to remove the lotion cartridge cover on the back and then remove the screws on the back of the inner cover. Remove the back to get to the inside of the shaver. The batteries are soldered to the circuit board. You can unsolder them or it is sometimes suggested that you use a modified installation technique. This is to break the tabs off of the old batteries rather than unsoldering them from the circuit board. This allows the old batteries to be removed but leaves the tabs attached to the circuit board. You can then solder the tabs from the new batteries to the old existing tabs. Reassemble in reverse order
If you are not able to do this repair yourself, shaveroutlet.com can do it for you. See link below
Answers & Comments
Yes, the batteries can be changed. You will find replacement batteries for model 6705X at shaveroutlet.com. See link below
http://shaveroutlet.com/shaver-battery-pack-for-most-norelco-more-p-278.html
To change the batteries, you will need to remove the lotion cartridge cover on the back and then remove the screws on the back of the inner cover. Remove the back to get to the inside of the shaver. The batteries are soldered to the circuit board. You can unsolder them or it is sometimes suggested that you use a modified installation technique. This is to break the tabs off of the old batteries rather than unsoldering them from the circuit board. This allows the old batteries to be removed but leaves the tabs attached to the circuit board. You can then solder the tabs from the new batteries to the old existing tabs. Reassemble in reverse order
If you are not able to do this repair yourself, shaveroutlet.com can do it for you. See link below
http://shaveroutlet.com/professional-battery-replacement-for-most-models-p-374.html