Establish multi-year reliability of energy-harvesting microsystems

Establish multi-year clinical and application-relevant reliability for integrated energy-harvesting microsystems, including resistance to mechanical fatigue, triboelectric-interface evolution, liquid-metal oxidation, thermal cycling, encapsulation degradation, storage aging, and environmental exposure.

Background

The review identifies long-term reliability as substantially less developed than short-term demonstrations of transducer performance. Degradation can occur across the entire energy pathway, including the harvester, interfaces, encapsulation, storage element, and power-management circuitry.

Although implantable demonstrations have shown autonomous operation for periods such as one month and stable in-vivo harvesting and pacing, the review states that these results do not establish multi-year clinical reliability. The unresolved problem is therefore to develop accelerated-aging methods, environmental-exposure tests, degradation and failure-mode analyses, and system-level metrics based on retained useful service rather than retained transducer output alone.

References

Long-duration reliability remains substantially less established than short-term transducer performance. Mechanical fatigue, triboelectric-interface evolution, liquid-metal oxidation, thermal cycling, encapsulation degradation, storage aging, and environmental exposure can progressively alter the energy pathway and shift the dominant system bottleneck. Recent implantable studies represent important progress. A symbiotic transcatheter pacemaker demonstrated one month of autonomous operation in a porcine disease model [130], while a TENG-powered leadless intracardiac pacemaker demonstrated stable in-vivo energy harvesting and pacing [141]. These results strengthen the evidence for integrated self-powered operation but do not yet establish multi-year clinical reliability.

— Energy Harvesting for Self-Powered Microsystems: A Critical Review of Materials, Power Management, and System Integration  (2609.20157 - Lin et al., 17 Sep 2026) in Section 9.1, Gap 2: “Long-Term Reliability Data is Practically Non-Existent”