After a time my Braun 320s-4 shaver still not have the endurance. The battery is after 2-3 minutes empty. So i decide to change the battery inside.
So lets start and remove the shaver head.
Now you see the three shaver blade adapter with the springs in the middle. The top of every shaver blade adapter is hold through two latching lugs. Just press the two latching lugs together and remove the top of the shaver blade adapter. Be carful, the latching lugs are really fragile. If one of the two latching lug breaks it is not a big problem because it works also with one latching lug.
After you remove the three tops of every shaver blade adapter it should look like this:
Now you can remove the springs and the bottom part of the shaver blade adapter by pulling it out. After you have done it, it should look like this:
I brake one of the latching lug, but it still works.
Now you can remove the two screws with a TX9 screw driver and remove the cover by pulling. After this it looks like this:
Now you can remove the two sealing rings at the screw holes.
After this you can remove the rubbered cover. Just use a screw driver to pry it out. It needs more force than i expected. But be careful and do not destroy it. After this it looks like this:
Now just pull of the cover.
Now you can also removed the big sealing ring at the head. After this remove the two TX9 Screws which holds the button cover. After this it looks like this:
Now pull the push button metal tongue to the top and remove the PCB with battery by pulling it up.
After this you can pry out the two AA Size Ni-MH batteries. I used a screw driver for it.
After this you have removed the batteries. They are a bit special because the have not the common connector type. But you can use normal Ni-MH AA batteries. Just bend the two connectors at the bottom to the directory of the other two connectors at the top. Now the normal Ni-MH AA batteries can be insert.
I use the high capacity 2700mAh Panasonic AA Ni-MH batteries. They cost me ~10$ and the original AA 1600mAh batteries i found for 24$.
Now just assemble it and have fun with the bigger and newer batteries in your shaver.
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