Although the latest patent was officially published today, its application date goes all the way back to August 2008. Additionally, Apple started work on more general patents for solar cells and portable devices back in October 2006. Those were eventually linked to Apple's iPod division.
You can check out Patently Apple's page for more of a rundown -- the stuff gets pretty technical, and the patent in this case seems to deal more with how solar cells could be used in an overall power management circuit, rather than in any device-specific manner. Still, because Apple already holds patents on powering iPod-like devices, it isn't a stretch to say that the company is investing in ways to bring solar cells to its portable products.
Will this technology extend to the Tablet? I guess we'll have to continue to wait and see. What do you think of solar powered electronics? Let us know!
[via CNET]