When I was testing the TH55 for my
review, I found that it averages about eight hours of typical use on a single charge. This is far better than most handhelds I've tested recently.
When I say "typical use" I mean I used it as my primary handheld for several days. I kept track of my schedule, did a good bit of Web surfing, checked my email, read an ebook, that sort of thing. This wasn't some kind of torture test.