As some you have figured out from talking with others if/when you loose weight battery placment may need to be changed. My unit is in my abdomen and that is where my doc USED to place all of the units. But due to increased risk of infection due to need to be turned during surgery and maintaining sterile field during that progress, he no longer places them in the abdomen. He has left mine in the abdomen with all of my upgrades and changes he has reluctantly left it there. (I can also be a pain in the rump patient as a nurse). I have told him and noted my placement changes up and down as I gain or loose weight also. It tends to slide further "south" with weight loss and "north" with weight gain. I have a feeling that with my next revision he may "insist" on giving me a "bionic butt", however I will do my best to keep it where it is.
z