Jim and Seiya’s Paper in IEEE Internet of Things. Congrats!!!

Paper title: Multi-cycle testing of commercial coin cells for buffering of harvested energy for the IoT

Abstract: The sensors and microprocessor-radios of the Internet of Things require power and one possibility is a hybrid source consisting of energy harvesting coupled with a rechargeable battery. This paper concerns a system with a low, but near constant, supply of harvested energy that is sufficient to slowly charge a battery, which buffers that energy and can then supply the higher power level necessary at data transmission. The cycle-life of the battery is then significant and this paper describes the cycling of a commercial lithium coin cell, Panasonic ML2020, for small depth of discharge. Initial work was on a Bio-Logic battery tester and cells were successfully tested, without failure, for a few million cycles at very shallow depth of discharge. Thereafter a battery tester was developed, based on the Particle Photon, that was much less expensive than a channel of a commercial battery tester. Four cells have been cycled, using this tester, for more than 50 million times with no deterioration in performance evident. Capacitors and a NiMH cell are being similarly tested.

Publication:

  1. Multi-cycle testing of commercial coin cells for buffering of harvested energy for the IoT James W. Evans, Bernard Kim, Seiya Ono, Ana C. Arias, and Paul K. Wright IEEE Internet of Things Journal, 2021 , . [Abstract] [Bibtex] [PDF]