Here I can only advise. The battery of my brush has just 6 (!!) persevered months, then was nothing more. And that's not an isolated incident, as you can see the many entries. While there's spare von Braun during the warranty period, the battery was improved but not even in the latest models, according to Braun Customer Service. And thus it is two years since then without ... or you own a spare battery builds up a what but requires appropriate technical skills. Technically, the brush is great, even the newer brush heads outstanding, but what good is the best brush when the battery makes the opponent in such a short time?