Periodic Reporting for period 1 - SYMPHONY (Smart Hybrid Multimodal Printed Harvesting of Energy)
Berichtszeitraum: 2020-05-01 bis 2021-10-31
The SYMPHONY project is addressing all these challenges with the development of an innovative energy autonomous sensor system. The energy supply in this system is made of printed, recyclable, and non-toxic materials including the ferroelectric polymer P(VDF-TrFE), printable Si-based rectifiers, redox polymer batteries and cellulose-based supercapacitors. The SYMPHONY project develops cost effective and scalable methods to print these materials on flexible films and to combine them with energy efficient electronics and sensor technologies. With the scalable and low-cost processing in combination with optimized ICs for energy harvesting the SYMPHONY project strives the goal of a specific cost below 1€/mW harvesting power.
Many parallel activities were performed in the material development. Several project partners collaborated on the development of P(VDF-TrFE) based composites either to form a stretchable piezoelectric material or to incorporate magnetic particles to form magnetoelectric materials. To prepare triboelectric nanogenerators tailor made electropositive and electronegative materials were created and 237 µC/m2 were achieved, which is close to the electrical breakdown of air in ambient conditions.
The efficient rectification of the generated current is crucial for the bipolar actuation of the nanogenerators. The mixing of silicon or zinc oxide particles in a flexible binder was investigated and showed the possibility to fabricate flexible rectifiers on solution-based processes.
The components for energy storage had great progress with the development of batteries based on redox polymers in different printing layouts leading to single cell and multicell structures in a co-planar and vertical design by screen-printing. To achieve this, perfectly adjusted materials were synthetized for anode cathode and electrolyte and a capacity of 0.2 mAh/cm2 was reached on materials level.
The printable or spray coatable supercapacitors based on a “power paper” consisting of nano fibrillated cellulose and PEDOT:PSS reached the goal of a specific capacity of 10mF/cm2 and an ESR (Equivalent series resistance) of 0.55 Ω.
The development of electronic components for the fabrication of energy autonomous sensing systems has started integrating an energy harvesting interface and Bluetooth Low energy communication into a general sensor chip and first prototypes are already fabricated for testing purposes within the consortium. A miniaturized discrete circuit for rectification and output regulation allows to operate the nanogenerators close to the maximum power point and deliver a constant voltage for battery charging or sensor powering.
First integration trials in the use cases were started including the testing of nanogenerators in a wind channel and the bicycle tube was equipped with sensors and mounted on a demonstrator. This goes hand in hand with the first steps regarding hybrid integration as investigation of stretchable conductors and/or lamination of piezo sensors.
The first material parameters have been delivered for an LCA analysis of the use cases and the preliminary boundaries of the investigated system have been identified.
The energy-efficient and scalable printing processes used in SYMPHONY offer significant cost reductions and energy savings as compared to high-temperature processes needed in manufacture of piezoceramics. In addition, the materials used in the project have a considerably lower environmental impact (cellulose, polymer batteries, lead-free piezoelectric).
The SYMPHONY energy autonomous sensor system will provide functionalities such as Condition Monitoring, Predictive Maintenance or Energy Management in 3 application areas: renewable energy generation, room heating/cooling and mobility. The SYMPHONY solution will significantly reduce CO2 emissions by increasing the lifetime of wind turbines, making room heating/cooling more efficient, through presence and motion tracking smart floors and decreasing the energy consumption in e-bikes, through remote tube pressure control.
The SYMPHONY printed technology can be integrated cost effectively in stretchable and flexible devices, representing a huge potential for usage in a wide range of further IoT-supported applications.
SYMPHONY will have impact not only in the field of applications for nanogenerators, but also at the material level since several material concepts developed in the project can also be applied for other purposes than energy harvesting. In fact, the new printable and cross linkable materials offer new processing routes such as UV-Nano Imprint Lithography, and inkjet printing, thereby enabling new integration methods and applications.