The objective of this study was two-fold. The first objectivewas to determine if the all-solid-state thin-film lithium energycells could withstand the minimal 550 kPa uniaxial pressurerequired for composite manufacturing, which both specimenssuccessfully did. The second objective was to determine theupper boundary uniaxial pressure limit of operation for theall-solid-state thin-film lithium energy cells. The two all-solid-state thin-film lithium energy cells tested in the presentstudy under uniaxial pressure performed well even whensubjected to uniaxial pressures up to about 2.0 MPa. However,pressures higher than this value led to their degradation.The observed degradation was due to the mechanicalfailure of the sealant. Above this pressure, the sealant wassqueezed out of the space between the two mica substratesand the lithium-metal anode layer, which in turn allowed theambient air to penetrate into the energy cell core, thus leadingto the rapid degradation of the charge and discharge performanceand the ultimate demise of the energy cell. We foundout that, within the observed range, uniformly distributed packaging characteristics, we found that allsolid-state thin-film energy cells charge/dischargecycles under upwardly increasinguniform uniaxial pressure are extraordinarilyrobust and resilient to the effects of uniaxial,uniformly distributed uniaxial pressure had little or no effect on the charge/dischargeperformance of the all-solid-state thin-film lithium energycells. Other power charge/draws outside of 1 mAh werenot of interest in this study for the reasons already pointedout, albeit that they may be considered for future studies.Apart from other considerations for failure due to the current andconstant power charge/sink of 1mAh. If theoverall structure of the energy cell is mechanicallyrobust, i.e., of high structural integrity,the maximum pressure that can beimposed is expected to be much higher thanthe maximum values noted earlier.The present study indicates that all-solidstatethin-film energy cells can be used as anintegral part of a load-bearing multifunctional,smart material structure if their packagingis of sufficiently high structural integrity.Hence, the goal of using fiber reinforcedlaminated composites as the packagingmaterial for all-solid-state thin-film batteriesin multifunctional smart materials structuresis well within reach.
|Numero di pagine||7|
|Rivista||Advanced Engineering Materials|
|Stato di pubblicazione||Published - 2008|
All Science Journal Classification (ASJC) codes