hang on you bought the batteries already but not the dock ? I think you wont be able to use the batteries then as each dock comes with its own batteries with contacts on the back to connect to the dock - these are today 3rd party products, if you have bought the micosoft ones they use a usb cable to charge. Actuall I have seen docks that have a usb connecter but I never use those as docks you can just drop the controller into are so much easier to use.
e.g.
like this for xbox one which is not junk (I love it)
Amazon product ASIN B00284AI3K