Question [Q] F320 battery contacts (wireless charging?)

I've just received an F320K (finally!) and have been mucking about with the fone salesman Qi receiver I have for my Note 3...

Does anyone know what the battery contacts at the back of this phone are for? There's a single pair and also a set of 4.

I've tried putting the receiver contacts against the ones on the phone but it's not charging. Weird that the back cover connects to the pair of contacts, although no idea why.

Has anyone looked into this?