With an overarching goal of providing greater autonomy to portable and stand-alone electronic devices, STMicroelectronics (ST) and the French Atomic Energy Commission (CEA) will collaborate in a four-year program to develop miniaturized energy sources for low-power applications. The two companies will establish a common laboratory, with facilities in both Tours and Grenoble, France, to research micro fuel cells and solid-state microbatteries. The research will also include thermoelectric- and mechanical-energy scavenging techniques that convert heat or physical motion into usable electricity.
The research team will total over 50 members, with roughly equal numbers assigned to ST’s manufacturing facility in Tours, and the CEA’s research facility in Grenoble—the CEA Laboratory of Innovation for New Energy Technologies and Nanomaterials (CEA Liten).
The joint research team will work on a variety of projects. The micro fuel cells, for example, will be specifically designed to power mobile phones using fuel that can be replenished at any time. According to Christian Nopper, R&D director at Tours, these fuel cells will not be based on conventional direct-methanol fuel-cell technology. Instead, the goal is to develop Sodium tetrahydroborate-based material for hydrogen generation.
In another project, the research into microbatteries to be conducted by the team is for use in applications such as “smart labels” and active RFID tags, which are expected to replace existing barcode technology. The researchers will exploit ST’s expertise in thin-film materials to advance microbattery technology, possibly expanding the range of applications to include medical implants, where replacing or recharging conventional batteries is difficult or impossible.
“The proliferation of portable devices has created a huge demand for energy sources such as rechargeable batteries but existing solutions still leave room for improvements in terms of performance, operating life and environmental impact. We believe that the complementary skills of ST and CEA Liten will lead to the development and industrialization of cost-effective new technologies that will meet these challenges”, said Carmelo Papa, Executive Vice President and General Manager of ST’s Industrial and Multisegment Sector (IMS).
In addition to power storage technologies, various energy-scavenging technologies will also be explored as part of the collaborative research. For example, while industrial environments offer many possibilities for energy scavenging due to the ample presence of vibration and waste heat, wearable systems can also provide ready access to vibration and heat. (Self-winding and electro-kinetic wristwatches are examples of wearable systems that harvest vibrations caused by the natural motion of the human body.) Therefore, according to Nopper, wearable systems will also be investigated as part of the collaborative research, but under the constraints of user friendliness and adaptability to the energy requirements of the intended applications.
While the potential sources of energy scavenging are limitless, the collaborative research effort between ST and the CEA will focus on sources with a high potential for practical applications. For example, a hands-free wireless earpiece for use with a cellular phone might be powered more effectively from body heat and mechanical vibration than the acoustical energy from the speaker’s voice. This is because acoustic-energy harvesting is considered inefficient due to the low intrinsic energy available, states Nopper.
Though the primary focus of the research is on energy conversion and storage, the electrical power conditioning requirements for the devices to be powered are also a concern. To meet these requirements, Nopper states that the systems to be developed could use off-the-shelf micropower conditioning technologies or components, depending on the application.