While the Oral-B Sonic Complete rechargeable toothbrush is great the battery life spam seems to be limited to about two years. After that time you can either throw the toothbrush away and get a new one, or replace the battery yourself. DIY battery replacement is not as difficult as it sounds. You just need the right kind of batteries (two GP100AFH NiMH rechargeable batteries) and a soldering iron. Some experience might help but if you are careful and double check if you got the polarity right, you should be fine.
First remove the brush head and open your Oral-B Sonic Complete rechargeable toothbrush by turning the bottom cap. Don’t loose the spring under the cap and don’t damage the wire that connect the cap with the toothbrush.
Now carefully push the metal part that usually holds the brush head until the old battery comes out. The battery is connected by wire to a small circuit board. Cut the wire off as close as possible to the old battery. This is the point where you will attach the new battery later.
Take your two batteries and solder them together. When you do that, take care that the batteries don’t get too hot or you might destroy them. Combine the positive pole of the first battery with the negative one of the second battery.
Use tape to wrap the batteries until all metal parts are covered and you have one big battery with solder tails sticking out at each end. Now bend the two tail towards one end.
Check the polarity and solder the two ends to the circuit board. Insert the battery, put the cap with the spring back and turn on your Oral-B Sonic Complete rechargeable toothbrush to check if it works.
What you need:
- Soldering iron
- wire cutter
- 2 GP100AFH NiMH rechargeable batteries
Here is a video for those of you who prefer to watch how it is done first.