Although the Voyager spacecraft have proved the long-term reliability of thermoelectric generators (TEGs) during their 40+ year missions, very little progress has been made in TEG technology in recent decades.
Matrix Industries has pioneered the development of TEGs based on silicon nanotechnology, which feature a unique combination of low thermal conductivity and high electrical conductivity. As a result, Matrix TEGs are dramatically more efficient at a significantly reduced cost compared to traditional TEG materials. These advances are covered by more than 10 patents and have been published in peer-reviewed journals. Matrix TEGs are scalable to produce from milliwatts to Kilowatts depending on your application.
Boost converters perform the difficult job of upconverting small thermoelectric output voltages to usable levels. Commercial boost converters are inefficient for use with thermoelectrics, often wasting 70% or more of the power because they are not optimized for such low voltage inputs.
Matrix Industries has developed a proprietary boost converter ASIC, specifically optimized to upconvert TEG output to power wireless circuits and charge lithium ion batteries. This gives our energy harvesting systems an even greater advantage in wireless wearable applications. The Matrix boost converter has a lower startup voltage and higher conversion efficiency at the input voltages supplied by thermoelectric generators. The Matrix boost converter is fabricated on a 180 nm process node optimized for power management integrated circuits.
In 2014 when Matrix started the design of the PowerWatch, the smallest wireless wearable prototype from an advanced research lab had a volume of over 100cc, approximately the size of a bar of soap, with no display or user input. In order to reduce that to a size that a consumer would find attractive (less than 40cc) and add modern smartwatch features, our design team had to attack multiple aspects of the thermal energy harvesting system design:
- The TEG hot side is bonded to an aluminum plate that conducts heat from a 20 square centimeter area of the outside of the user’s wrist (users who wear the PowerWatch on the inside of their wrist harvest significantly more power!)
- The heat is channeled through the TEG and out to the watch body by an intricate transport structure.
- The body of the watch is insulated from the bottom plate by a frame cast of thermoplastic chosen for its insulating properties.
Thermal systems design is the most difficult aspect of any wearable energy harvesting project. For this reason, Matrix provides thermal engineering & design services to our OEM customers.
Matrix Industries thermoelectric technology is available now to power your wearable and wireless IoT products. Please contact us at firstname.lastname@example.org for more information or to request samples.