  Wearable thermoelectric devices show promises to generate electricity in a
ubiquitous, unintermittent and noiseless way for on-body applications.
Three-dimensional thermoelectric textiles (TETs) outperform other types in
smart textiles owing to their out-of-plane thermoelectric generation and good
structural conformability with fabrics. Yet, there has been lack of efficient
strategies in scalable manufacture of TETs for sustainably powering
electronics. Here, we fabricate organic spacer fabric shaped TETs by knitting
carbon nanotube yarn based segmented thermoelectric yarn in large scale.
Combing finite element analysis with experimental evaluation, we elucidate that
the fabric structure significantly influences the power generation. The
optimally designed TET with good wearability and stability shows high output
power density of 51.5 mW/m2 and high specific power of 173.3 uW/(g.K) at delta
T= 47.5 K. The promising on-body applications of the TET in directly and
continuously powering electronics for healthcare and environmental monitoring
is fully demonstrated. This work will broaden the research vision and provide
new routines for developing high-performance and large-scale TETs toward
practical applications.
