20 - 30 minutos
The battery was so bad that I could not use the GPS feature for more than 15 minutes and making calls when the temperature outside was cold was a joke. Was looking into buying a new phone but though I would try replacing the battery.
The repair was a lot easier than I thought. Was a bit nervous but it all went well as far as I can tell.
I watched a YouTube video of the repair and had my computer handy with the instruction and photos to help along the way. Make sure you have 15 to 30 minutes to dedicate with out interruptions.