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A concept is presented for remote, autonomous sensors, which includes an on-board power supply, signal transmission, a sensing element, and a controller. Sensors can be deployed without direct connection for either signal transmission or energy supply. The power supply can be used to power many types of remote sensors, and includes microscopic batteries, an energy converter, and a simple charger. The batteries combine high power density (W/cm2) and sufficient capacity to power sensors for extended periods of time without recharge.

This paper describes electrochemical behavior of microscopic batteries based on both the lithium/ion and Ni/Zn couples. These batteries are being developed for use in MEMS devices and other microelectronics, especially remote, autonomous sensors. Many of these applications require a combination of long cycle life, moderate energy storage capability, and periodic high power output. Batteries have been made using high-volume, lowcost, fabrication techniques, described in prior publications. These batteries have been built and evaluated for their electrochemical performance. Power output from both types of cells is impressive; current densities of 80 - 100 and 20 - 50 mA/cm2 have been observed, for discharges of several seconds, for Ni/Zn and Li/Ion cells, respectively. Much higher current densities are observed for discharges lasting a few milliseconds, such as would be needed in many applications. Specific capacities of 2 - 4 C/cm2 are also obtained.