FLEXIBLE ELECTROSTATIC KINETIC ENERGY HARVESTER

Our device converts mechanical energy into electricity, when repeatedly pressed and released by an external mechanical action. The device has a sandwich structure, with flexible or solid electrodes on the surface and with an organic electret material core (see picture). It can be embedded into an object, a cloth or be used as a “second skin”.

Electric charges trapped within the device induce an electric current through a charge when a mechanical deformation is applied. The device has no resonance frequency and thus works at any mechanical frequency. Besides, the organic material is designed in such a way so that electric charges remain stable over time, leading to long standing performances. With a finger tapping activation, the first 3cmx3cm prototype reaches a peak voltage of 27 V and a power of 45.6 μW. Performances can be further largely enhanced by optimizing triboelectric effect, increasing the size of the device and/ or by using it under different conditions (higher mechanical frequencies, more pressure).

Applications

Powering/improving battery lifetime for :

• Embedded chips in smart clothes and shoes
• “Second skin” biomedical sensors
• Smart cards, semi-active RFID systems,
• Strain or pressure sensors (for car wheels for example)

Competitive advantages

• Flexible or solid surface
• Works at any mechanical frequency
• Long standing electric charge storage

Intellectual property

Pending patent

Keywords

Mechanical (kinetic) energy harvester - (Tribo)electret material - Triboelectricity - Electrostatic transducer