A former Apple executive told the paper that engineers at Apple have been trying to add solar charging to iPhones and iPods for many years and they continue to experiment with the technology.
However, some in Silicon Valley, including Tony Fadell, a former Apple VP, think betting on battery tech isn't a good idea. “Hoping and betting on new battery technology to me is a fool’s errand,” said Fadell. “Don’t wait for the battery technology to get there, because it’s incredibly slow to move.”
Fadell notes that while Apple has tried for many years to add solar power to its mobile devices, the method was never practical because most of the time these devices are in your pocket. Additionally, indoor artificial light only generates a small amount of energy.
Despite those concerns, NYT sources note that Apple is considering a method of solar charging for its rumored iWatch.
Apple has also experimented with new power-charging methods for a potential smartwatch, people close to the efforts said, though such experiments are years from becoming a reality. The watch is expected to have a curved glass screen, and one idea is to add a solar-charging layer to that screen, which would give power to the device in daylight, they said.
Apple is also looking into other ways to improve its battery technology. Over the past few years, Apple has hired engineers who are experts in the field from companies like Tesla, Toyota and A123 Systems. The company has reportedly been testing a method to charge the batteries wirelessly via magnetic induction and a method that involves charging a battery through movement. For example, a person's arm swinging might generate power for the rumored iWatch.
Notably, a recent prediction from analyst Matt Margolis suggests that Apple not only plans to use sapphire glass for the iPhone 6 but that the sapphire glass will also function as a solar charging panel for the device.
More details in the full report linked below...