Frank, jcarm75 ...
I too made the mistake of damaging the copper foil (yes, copper) that is in fact on the back side of the battery covering the charging coil. I had downloaded the guide in PDF form and was following the instructions on a second Touchpad so wasn't aware of the copper foil on the back of the battery. Steps 27 and 28 discuss carefully removing (prying) the battery and it's mentioned that there may be tape securing it to the case but I was very surprised by the presence of the copper foil and coil.
I don't believe I damaged the coil but the copper foil was torn to the point of separation and is now in two pieces. I went ahead with reassembly (and placed the foil as best I could) and now the device displays an empty battery with question mark with NO indication of any charge.
If anyone has suggestions on what to try next, that would be terrific. I think the USB connection and board are okay but don't know how to confirm. I think the device is usable if the battery/foil/charging questions can be sorted.
I mostly want to affirm that there IS definitely copper foil and one must use care or it will be torn and may be rendered useless -- though I don't know for certain one way or the other.