TCL Communication, a Chinese mobile phone manufacturer, is developing smartphones that recharge themselves using solar power. A phone is rather small for a solar panel, but it's using transparent Wysips Crystal technology that is bonded to the smartphone screen.

Wysips Crystal -- which stands for What You See Is Photovoltaic Surface -- has been developed by Sunpartner, which is based in the south of France. Sunpartner says: "The goal of this partnership is to develop smartphone prototypes powered by solar and artificial light. This project will enable TCL Communication to evaluate the technology in both technical and marketing terms."

TCL also has a French connection, in that it supplies Alcatel with its OneTouch mobile phone. It markets phones in more than 120 countries.

The companies expect that putting an ultra-thin layer of Wysips Crystal under the screen will enable a smartphone to generate enough power to maintain a charge. It hopes an hour of sunlight will provide enough power for 30minutes of conversation.

Sunpartner is also working with another two large phone companies. It says it "plans to finalize two agreements in the coming months and sign the first licenses during the first half of 2014."

Last month, Sunpartner completed a second round of funding, bringing its total to €9 million over the past three years, and it plans to raise another €6 million to put Wysips Crystal into production in Rousset, near Aix-en-Provence. (See Recharge : SunPartner, fabricant d’un film solaire pour écrans, signe un accord avec TCL at ZDNet.fr).

Sunpartner says Wysips Crystal could also be used in tablets and e-book readers, watches, electronic tags etc, and in intelligent buildings (windows, facades etc).

Sunpartner showed its first prototypes at the Mobile World Congress in Barcelona in February.