DOI: 10.3390/app16199571 ISSN: 2076-3417

Degradation of Silver-Coated Conductive Elements in Electronic Textile Interfaces: A Single-Stressor Evidence Map and the Case for Multi-Stressor Testing

Chai Young Lee

Silver-coated yarns, hook-and-loop fasteners, dry electrodes, and snap connectors are the most common means of establishing electrical contact in smart garments, owing to silver’s favorable conductivity, lower cost relative to gold, and compatibility with flexible fiber coatings. In practice, however, these components fail in a recurring pattern: the silver coating wears away or corrodes, and the electrical path is interrupted. This problem has, until now, been studied by separate research communities that rarely cite one another: tribology researchers have characterized how silver connectors wear under vibration, textile researchers have examined how they degrade during washing and sweat exposure, and coating researchers have investigated how the coating itself is applied. This review systematically maps evidence across these three strands of the literature and evaluates, pathway by pathway, the strength of support for each. Six degradation pathways are examined, namely vibration, repeated plugging and unplugging, laundering, sweat exposure, atmospheric exposure, and fiber or debris entrapment, and all six are found to be consistent with a single underlying mechanism: loss of the silver layer and a consequent reduction in working contact points, with three of these pathways, fretting, laundering, and perspiration corrosion, supported by direct measurement. One study further shows that short-term sweat exposure can transiently increase conductance before longer exposure reduces it, indicating that this degradation is not strictly a one-way process. The review also compares coating deposition methods and identifies a mitigation strategy proposed independently for two of the six pathways: adding a second conductive layer, such as carbon nanotubes or a thin gold overcoat, that remains functional after the underlying silver is depleted, although this strategy has not yet been cross-validated between pathways. Because nearly every study reviewed here tests only a single stressor at a time, with genuine combined-stress evidence limited to one study, this review argues that more realistic, combined-stress testing is still needed and proposes a concrete framework for such testing.