Motorola recently patented technology that combines a solar cell with the LCD screen of a mobile phone. The solar cells are essentially a thin film called transparent conductive oxides that resides on top of the LCD, collects energy, and passes it to the battery. In theory, the technology would allow cell phones to charge whenever their LCDs are exposed to sunlight. According to Motorola’s patent information, black LCDs with a 75% let-through rate work best with the technology.