IEDM 2019 Paper Reports Millimeter-Scale TFBs Exhibit the Best Performance In Both Energy and Power Densities
SAN FRANCISCO – Dec. 10, 2019 – In a research result that potentially could expand the market for tiny energy-storage units in medical implantable, injectable and wearable solutions, CEA-Leti has fabricated all-solid, inorganic thin-film batteries (TFBs) that demonstrate better performance than existing devices.
During its presentation at IEDM 2019, a CEA-Leti team reported that, “Thin-film batteries provide some of the highest energy densities of electrochemical energy storage devices, but the inability to increase the electrodes’ thicknesses and control the geometry on the micrometer scale has thus far hindered their effective areal energy density and integration in miniaturized devices.”
“We demonstrate an areal energy density of 890 μAh.cm-2, the highest reported so far for such devices,” the paper says. “Furthermore, we show that the new TFB architecture exhibits high power density, reaching capacity as high as 450 μAh.cm-2 under 3mA.cm-2 current density.”
The continued miniaturization of electronics has highlighted the need for highly integrated electrochemical energy storage, while storage at the point of load reduces dissipation from power loss and I/O switching noise that limits the effectiveness of sensitive devices in unique form factors. Recent progress in the microfabrication of integrated electrochemical capacitors offers high-power density and high-frequency response, but the low energy densities of these devices can inhibit the use of microelectromechanical systems (MEMS) and autonomous device applications that require long periods between charging.
The team’s solution to these challenges is a high-energy-density, millimeter-scale, thin-film battery integrating 20μm-thick LiCoO2 cathode in a Li-free anode configuration.
“Implantable sensors or biological-function monitoring systems such as intraocular pressure sensors and blood-glucose measurement would be particularly suited for our TFBs,” said Sami Oukassi, lead author of the paper, “Millimeter Scale Thin-Film Batteries for Integrated High-Energy-Density Storage”. “External systems, i.e. cochlear implants and smart contact lenses would also benefit from the advantages of this breakthrough.”
Additional highlights of the study include:
- Millimeter-scale TFBs exhibit the best performance in terms of energy and power densities: 0.8mAh/cm² and up to 12mW/cm², and
- The fabrication process is viable for industrial large-scale production and allows easy control and fine-tuning of the device electrochemical properties.
“Battery manufacturers have been struggling to produce a power source that not only functions at the micro-scale but has high power density and energy,” Oukassi said. “CEA-Leti TFBs offer this opportunity with the highest performance reported so far, compared with current TFBs and micro-supercapacitor solutions.”
About Leti (France)
Leti, a technology research institute at CEA Tech, is a global leader in miniaturization technologies enabling smart, energy-efficient and secure solutions for industry. Founded in 1967, Leti pioneers micro-& nanotechnologies, tailoring differentiating applicative solutions for global companies, SMEs and startups. Leti tackles critical challenges in healthcare, energy and digital migration. From sensors to data processing and computing solutions, Leti’s multidisciplinary teams deliver solid expertise, leveraging world-class pre-industrialization facilities. With a staff of more than 1,900, a portfolio of 2,700 patents, 91,500 sq. ft. of cleanroom space and a clear IP policy, the institute is based in Grenoble, France, and has offices in Silicon Valley and Tokyo. Leti has launched 60 startups and is a member of the Carnot Institutes network. Follow us on www.leti-cea.com and @CEA_Leti.
Follow us on www.leti.fr/en and @CEA_Leti.
CEA Tech is the technology research branch of the French Alternative Energies and Atomic Energy Commission (CEA), a key player in innovative R&D, defence & security, nuclear energy, technological research for industry and fundamental science, identified by Thomson Reuters as the second most innovative research organization in the world. CEA Tech leverages a unique innovation-driven culture and unrivalled expertise to develop and disseminate new technologies for industry, helping to create high-end products and provide a competitive edge.
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