Wireless keyboards with rechargeable Li-ion batteries?

[Willeh]

Happy New Year!,
I'm buying a Logitech MX Revolution Mice and I was wondering if there are any wireless keyboards that follow the MX Rev technology?, which is having a Li-On battery which is rechargeable?

Logitech does one called 'DiNovo Edge' but it's £100 which in my opinion, is a bit too much for a keyboard.

Thanks