I can’t imagine there would be. Proprietary stuff is always more expensive and not necessarily the highest quality. Not to mention you can’t use them in other devices. I highly recommend the NiMH batteries sold by Costco (and charger, if you don’t have one). IIRC the brand name is Eneloop.
When possible, I tend to stick with the non-specific batteries and chargers. I bought a whole pile of rechargeable AAs back when I had my Wii, and they’d be pretty worthless to me now if they’d only worked in the Wiimotes. It also tends to be cheaper this way.