How about a transmitter pack that incorporates a wireless charging coil & electronics? Most transmitter packs are roughly the size and capacity of a large smartphone's battery, and they use a similar amount of power.
Ideally, you wouldn't even have to remove it from the transmitter to charge it, just plop the whole transmitter on top of your wireless charging pad and let it charge through the bottom of the battery bay. One fewer set of electrical contacts to loosen/wear over time.
Ideally, you wouldn't even have to remove it from the transmitter to charge it, just plop the whole transmitter on top of your wireless charging pad and let it charge through the bottom of the battery bay. One fewer set of electrical contacts to loosen/wear over time.