I must have had mine around 5 years. Got a double pack at Costco - came with one charger but two handles. Seems to me they are both going strong. I charge one, use it until it signals me that it's losing power (it beeps several times when you finish brushing, that's how it lets you know). At that point, I take off the head, clean it and set it aside and charge the other handle, the one that's been sitting around unused the last few weeks. That charge takes about 20-22 hours, so since I brush once a day, by the time I'm ready to brush, the handle's got a full charge (the light stops blinking and is steady on). Never counted, but I'd estimate that I get around 20-25 2-minute brushes (maybe more) out of a single charge using this swap method, brushing daily. My dentist said to use a bit of toothpaste about the size of 1/2 a pea.