If you have tried to remove battery from iPhone 5S or 5C, you’d know how hard it is to remove battery as it is glued strongly to the frame. If you force it to remove the battery, it will look like this.
When the battery looks like this, you really don’t want to reuse it as the core is damaged inside and may damage the phone.
If the battery is removed to replace with a new unit, it would not matter, but when you want to re-use the battery, you have to remove it without damaging it.
We have created a video to show you how to remove iPhone 5S battery from its housing properly. Please see the video. Hope you lean something. Enjoy.