10 - 30 minuten
I purchased two used iPhone 4s's both had battery issues. One would only hold a charge for 5 hours or so the other 6 hours tops. Both were draining even during sleep mode. So I figured the batteries were ready to go, for this old of a model I really didn't want to pay $100+ each to have someone else repair it.
I ordered 2 batteries and the liberation kit from iFixit. Watched the video as well as read the instructions.
The repair for the first one took about 15 minutes. The battery was stuck down and pretty hard to pry off, so much so it bent one end of the pry device not to mention the battery. I did end up shorting out the old battery (yes it sparked too!) but it was not connected, so very important to disconnect the battery prior to trying to removing it. I was almost worried I was going to break the phone with the prying and the short, but it was fine. The second phone took about 5 minutes. Very easy repair with the kit.
I am happy to say that now they last a couple of days with moderate use. One that gets less use lasted 3 days before needing a charge! I can now leave the phone with 100% charge in sleep mode over night and when I check it in the morning it's still at 100%! They even seem to respond faster with the new batteries.
My recommendation is for a good pair of tweezers, some high magnification reading glasses, and watch the video first, also best to keep the repair on a lint free cloth so you don't lose the tiny screws that need to be removed.
I did not use the windex to clean the contacts. I was just careful not to put my hands on any of the connection parts, by using tweezers.
Be patient with the battery removal if it's stuck down as good as my first phone you will have to pry slowly and carefully so it doesn not damage the phone. Best bet is to get under it with another object (I used a butter knife)and push the pry bar under it carefully to get the adhesive to separate.
I have read a lot of stories about cheap batteries sold on other sites. Most say you never know what you are getting. IFixit had a good reputation so I purchased from them. I have to say I am glad I did. The batteries from iFixit are top notch.