To replace, you will need to remove the back cover by removing the two screws on the back. You will then need to remove the two metal clips inside so that you can access the battery pack.
Batteries are soldered to the circuit board but for easier replacement, 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
If you are not able to do this repair yourself, Shaver Outlet can do it for you. See link below
Answers & Comments
You will find batteries for model 7825XL at shaveroutlet.com. See link below
http://shaveroutlet.com/shaver-battery-pack-for-most-norelco-more-p-278.html
To replace, you will need to remove the back cover by removing the two screws on the back. You will then need to remove the two metal clips inside so that you can access the battery pack.
Batteries are soldered to the circuit board but for easier replacement, 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
If you are not able to do this repair yourself, Shaver Outlet can do it for you. See link below
http://shaveroutlet.com/professional-battery-replacement-for-most-models-p-374.html