A Combinatorial Study of Li y Mn x Ni2 − x O 4 Cathode Materials Using Microfabricated Solid-State Electrochemical Cells

A methodology for batch-fabricating hundreds of submillimeter thin-film solid-state batteries was used in conjunction with a combinatorial materials synthesis technique. This approach allowed for the simultaneous creation of many solid-state microbatteries that had Li v Mn x Ni 2-x O 4 cathodes, where x varied continuously from 0.2 to 1.8 and y varied from 2.7 to 3.7 in the as-deposited films. Sputtered lithium phosphorous oxynitride (LiPON) was used as an electrolyte, while evaporated, micropat-temed Li metal served as the anode layer. The composition, thickness, and microstructure of the cathodes were examined using X-ray energy-dispersive spectroscopy, synchrotron-based X-ray diffraction, Rutherford backscattering spectroscopy, stylus profilometry, inductively coupled plasma mass spectroscopy, and scanning electron microscopy. Electrochemical cycling data allowed for cell performance to be correlated to cathode composition and structure. Cathodes with a composition of LiMn 1.4 Ni 0.6 O 4 had both the highest specific capacity as well as the longest high-potential (4.7 V) discharge plateau, while cells with higher Mn content had a longer 4 V discharge plateau, a result that qualitatively agrees with similar studies on conventional bulk-fabricated cathodes of the same material.

[1]  S. Dou,et al.  Improvement of electrochemical properties of the spinel LiMn2O4 using a Cr dopant effect , 1999 .

[2]  N. Dudney,et al.  Lithium Diffusion in LixCoO2 (0.45 < x < 0.7) Intercalation Cathodes , 2001 .

[3]  J. Bates.  Thin-Film Lithium and Lithium-Ion Batteries , 2000 .

[4]  John B. Goodenough,et al.  LixCoO2 (0, 1980 .

[5]  J. D. Robertson,et al.  Lithium Manganese Nickel Oxides Li x ( Mn y Ni1 − y ) 2 − x O 2 I. Synthesis and Characterization of Thin Films and Bulk Phases , 1998 .

[6]  Xianglan Wu,et al.  Improvement of electrochemical properties of LiNi 0.5Mn 1.5O 4 spinel , 2002 .

[7]  B. Popov,et al.  Electrochemical investigation of CrO2.65 doped LiMn2O4 as a cathode material for lithium-ion batteries , 1998 .

[8]  T. Umegaki,et al.  Electrochemical Characteristics of LiNi0.5Mn1.5 O 4 Cathodes with Ti or Al Current Collectors , 2002 .

[9]  Z. Rek,et al.  Analysis of thin film stress measurement techniques , 1997 .

[10]  F. Hart,et al.  LATTICE MODEL CALCULATION OF THE STRAIN ENERGY DENSITY AND OTHER PROPERTIES OF CRYSTALLINE LICOO2 , 1998 .

[11]  P. Fragnaud,et al.  Thin-film cathodes for secondary lithium batteries , 1995 .

[12]  J. Dahn,et al.  Economical sputtering system to produce large-size composition-spread libraries having linear and orthogonal stoichiometry variations , 2002 .

[13]  Brian C. Sales,et al.  Characterization of Thin‐Film Rechargeable Lithium Batteries with Lithium Cobalt Oxide Cathodes , 1996 .

[14]  J. Whitacre,et al.  The influence of target history and deposition geometry on RF magnetron sputtered LiCoO2 thin films , 2001 .

[15]  J. Dahn,et al.  Synthesis and Electrochemistry of LiNi x Mn2 − x O 4 , 1997 .

[16]  I. Petrov,et al.  Use of an externally applied axial magnetic field to control ion/neutral flux ratios incident at the substrate during magnetron sputter deposition , 1992 .

[17]  J. D. Robertson,et al.  Nanocrystalline Li x Mn2 − y O 4 Cathodes for Solid‐State Thin‐Film Rechargeable Lithium Batteries , 1999 .

[18]  W. R. McKinnon,et al.  Synthesis conditions and oxygen stoichiometry effects on Li insertion into the spinel LiMn[sub 2]O[sub 4] , 1994 .

[19]  K. Striebel,et al.  Electrochemical Behavior of LiMn2 O 4 and LiCoO2 Thin Films Produced with Pulsed Laser Deposition , 1996 .

[20]  K. Amine,et al.  Preparation and electrochemical investigation of LiMn2 − xMexO4 (Me: Ni, Fe, and x = 0.5, 1) cathode materials for secondary lithium batteries , 1997 .

[21]  Jay F. Whitacre,et al.  Crystallographically Oriented Thin-Film Nanocrystalline Cathode Layers Prepared Without Exceeding 300°C , 2001 .

[22]  H. Windischmann.  Intrinsic Stress in Sputter Deposited Thin Films , 1992, Optical Interference Coatings.

[23]  K. Amine,et al.  A New Three‐Volt Spinel Li1 + x Mn1.5Ni0.5 O 4 for Secondary Lithium Batteries , 1996 .

[24]  N. Dudney,et al.  5 Volt Plateau in LiMn2 O 4 Thin Films , 1995 .

[25]  J. Whitacre,et al.  Fabrication and testing of all solid-state microscale lithium batteries for microspacecraft applications , 2002 .

[26]  Lithium Manganese Nickel Oxides Li x ( Mn y Ni1 − y ) 2 − x O 2 II. Electrochemical Studies on Thin‐Film Batteries , 1998 .

[27]  J. Tarascon,et al.  Li Metal‐Free Rechargeable Batteries Based on Li1 + x Mn2 O 4 Cathodes ( 0 ≤ x ≤ 1 ) and Carbon Anodes , 1991 .