10 - 30 分钟
My iPhone 4s was only charging when I shut it down completely. Could not synchronize with iTunes, nor charge it while on.
It took me about some 40 minutes to replace the battery and the dock connector. I used the screwdrivers iFixit sent as well as the battery and dock connector replacement. I had no previous experience on opening up an iPhone so I was kind of nervous of screwing up big time. But nothing went wrong.
I had to watch several videos on youtube before embarking on my little adventure. I chose the best ones to aid me while I did surgery on my iPhone. Also, not included on the iFixIt, but really useful as I have very big hands, are tweezers as many of things inside the iPhone are really small.