Laser Direct-Write Of Alkaline Microbatteries
- PDF / 150,517 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 12 Downloads / 223 Views
LL3.8.1
Laser Direct-Write Of Alkaline Microbatteries Craig B. Arnold and Alberto Piqu´e Materials Science and Technology Division Naval Research Laboratory, Washington, DC 20375, USA ABSTRACT We are developing a laser engineering approach to fabricate and optimize various types of alkaline microbatteries. Microbattery cells are produced using a laser forward transfer process that is compatible with the materials required to make the anode, cathode, separator and current collectors. The use of an ultraviolet transfer laser (wavelength = 355 nm, 30 ns FWHM) enables other operations such as surface processing, trimming and micromachining of the transferred materials and substrate and is performed in situ. Such multi-capability for adding, removing and processing material is unique to this direct-write technique and provides the ability to laser pattern complicated structures needed for fabricating complete microbattery assemblies. In this paper, we demonstrate the production of planar zinc-silver oxide alkaline cell by laser direct-write under ambient conditions. The microbattery cells exhibit 1.5-1.6 V open circuit potentials, as expected for the battery chemistry and show flat discharge behavior under constant current loads. INTRODUCTION Over the last two decades, there has been a continuing trend toward smaller and more autonomous micro-electronic sensing and microelectromechanical devices and systems. As this miniaturization pushes forward, the classical concept of an independent, monolithic power source is no longer sufficient to meet the demands of these advanced devices [1, 2, 3]. In these cases, one of the main concerns is the necessary reduction in both area and thickness of the power source to meet the geometric requirements for integration with the microdevices. There has been much effort to develop small microbatteries for various primary and secondary chemistries. One successful approach for the lithium based system uses solid state electrolytes in a stacked configuration [4, 5]. In this case, the anode, cathode, and solid-state electrolyte are deposited using standard physical vapor deposition techniques in vacuum with patterning through photolithography. In other experiments, alkaline microbatteries have been produced in a planar configuration where the anode and cathode are located adjacent to each other on the substrate [6, 7]. In this case, materials are deposited through electrochemical and vacuum techniques while the patterning is accomplished through photolithography. An alternative approach to the production of microbattery cells is through laser engineering [8, 9]. In this technique, we use laser direct-write to directly deposit material where needed [10, 11, 12]. Subsequent laser processing such as annealing or machining is performed in situ without the need to remove the substrate. Under this approach, there is no need for expensive vacuum or lithographic processing as all stages of cell construction are performed under atmospheric conditions. Furthermore, our technique does not require re-en
Data Loading...
