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CRADA Final Report: Properties of Vacuum Deposited Thin Films of Lithium Phosphorous Oxynitride (Lipon) with an Expanded Composition Range

Description: Thin films of an amorphous, solid-state, lithium electrolyte, referred to as ''Lipon'', were first synthesized and characterized at ORNL in 1991. This material is typically prepared by magnetron sputtering in a nitrogen plasma, which allows nitrogen atoms to substitute for part of the oxygen ions of Li{sub 3}PO{sub 4}. Lipon is the key component in the successful fabrication of ORNL's rechargeable thin film microbatteries. Cymbet and several other US Companies have licensed this technology for commercialization. Optimizing the properties of the Lipon material, particularly the lithium ion conductivity, is extremely important, yet only a limited range of compositions had been explored prior to this program. The goal of this CRADA was to develop new methods to prepare Lipon over an extended composition range and to determine if the film properties might be significantly improved beyond those previously reported by incorporating a larger N component into the film. Cymbet and ORNL investigated different deposition processes for the Lipon thin films. Cymbet's advanced deposition process not only achieved a higher deposition rate, but also permitted independent control the O and N flux to the surface of the growing film. ORNL experimented with several modified sputtering techniques and found that by using sectored sputter targets, composed of Li{sub 3}PO{sub 4} and Li{sub 3}N ceramic disks, thin Lipon films could be produced over an expanded composition range. The resulting Lipon films were characterized by electrical impedance, infrared spectroscopy, and several complementary analytical techniques to determine the composition. When additional N plus Li are incorporated into the Lipon film, the lithium conductivity was generally degraded. However, the addition of N accompanied by a slight loss of Li gave an increase in the conductivity. Although the improvement in the conductivity was only very modest and was a disappointing conclusion of this study, forcing a higher N ...
Date: December 29, 2003
Creator: Dudney, N.J.
Partner: UNT Libraries Government Documents Department

Thin-film rechargeable lithium batteries with amorphous Li{sub x}Mn{sub 2}O{sub 4} cathodes

Description: Cathode films of amorphous Li{sub x}Mn{sub 2}O{sub 4} have been grown by rf magnetron sputtering on unheated substrates. A low process gas pressure and a positive substrate bias were found to give the most conductive cathodes. The batteries were completed with subsequent deposition of a lithium phosphorous oxynitride electrolyte and Li anode. These cells were cycled at 25-100 C between 4.5 and 1.5 V which corresponds to {approximately}0 to 2 Li per Mn{sub 2}O{sub 4}. The amorphous cathodes have a highs pecific capacity and a low capacity loss per cycle.
Date: January 1, 1996
Creator: Dudney, N.J.; Bates, J.B.; Lubben, D. & Hart, F.X
Partner: UNT Libraries Government Documents Department

Recent Developments in Thin-Film Lithium and Lithium-Ion Batteries

Description: This report on recent developments in thin-film lithium and lithium-ion batteries displays experimental data related to high-rate deposition and annealing, metal foil substrates, tin and zinc nitride anodes, lithium plating (``lithium-free'' lithium cells), manufacturing and applications. Challenges and future work include improving the yield of batteries on metal foils by electrical isolation of anode current collector from substrate, and lowering manufacturing costs by increasing deposition and processing rates of electrolyte and cathode films.
Date: January 4, 1999
Creator: Bates, J.B.; Dudney, N.J. & Neudecker, B.J.
Partner: UNT Libraries Government Documents Department

Thin-film rechargeable lithium batteries for implantable devices

Description: Thin films of LiCoO{sub 2} have been synthesized in which the strongest x-ray reflection is either weak or missing, indicating a high degree of preferred orientation. Thin-film solid state batteries with these textured cathode films can deliver practical capacities at high current densities. For example, for one of the cells 70% of the maximum capacity between 4.2 V and 3 V ({approximately}0.2 mAh/cm{sup 2}) was delivered at a current of 2 mA/cm{sup 2}. When cycled at rates of 0.1 mA/cm{sup 2}, the capacity loss was 0.001 %/cycle or less. The reliability and performance of Li-LiCoO{sub 2} thin-film batteries make them attractive for application in implantable devices such as neural stimulators, pacemakers, and defibrillators.
Date: May 1, 1997
Creator: Bates, J.b. & Dudney, N.J.
Partner: UNT Libraries Government Documents Department

Thin-film Li-LiMn{sub 2}O{sub 4} batteries

Description: Thin-film rechargeable Li-LiMn{sub 2}O{sub 4} batteries have been fabricated and characterized. Following deposition by electron beam evaporation of LiMn{sub 2}O{sub 4}, the amorphous as-deposited cathode films 1 cm{sup 2} in area by 0.3 to 4 {mu}m thick were annealed at 700{degree}C to 800{degree}C in oxygen in order to form the crystalline spinel phase. The capacity of the cells between 4.5 V to 3.8 V depended on the annealing conditions and ranged from 50 {mu}Ah/mg to 120 {mu}Ah/mg. When cycled over this range, the batteries exhibited excellent secondary performance with capacity losses as low as 0.001% per cycle. On charging to 5.3 V, a plateau with a median voltage of 5.1 V was observed. The total charge extracted between 3.8 V to 5.3 V corresponded to about 1Li/Mn{sub 2}O{sub 4}.
Date: November 1, 1994
Creator: Bates, J.B.; Lubben, D. & Dudney, N.J.
Partner: UNT Libraries Government Documents Department

Thin-film rechargeable lithium batteries

Description: Small thin-film rechargeable cells have been fabricated with a lithium phosphorus oxyniuide electrolyte, Li metal anode, and Li{sub 1-x}Mn{sub 2}O{sub 4} as the cathode film. The cathode films were fabricated by several different techniques resulting in both crystalline and amorphous films. These were compared by observing the cell discharge behavior. Estimates have been made for the scale-up of such a thin-film battery to meet the specifications for the electric vehicle application. The specific energy, energy density, and cycle life are expected to meet the USABC mid-term criteria. However, the areas of the thin-films needed to fabricate such a cell are very large. The required areas could be greatly reduced by operating the battery at temperatures near 100{degrees}C or by enhancing the lithium ion transport rate in the cathode material.
Date: November 1, 1994
Creator: Dudney, N.J.; Bates, J.B. & Lubben, D.
Partner: UNT Libraries Government Documents Department

Thin-film rechargeable lithium batteries

Description: Thin-film rechargeable lithium batteries using ceramic electrolyte and cathode materials have been fabricated by physical deposition techniques. The lithium phosphorous oxynitride electrolyte has exceptional electrochemical stability and a good lithium conductivity. The lithium insertion reaction of several different intercalation materials, amorphous V{sub 2}O{sub 5}, amorphous LiMn{sub 2}O{sub 4}, and crystalline LiMn{sub 2}O{sub 4} films, have been investigated using the completed cathode/electrolyte/lithium thin-film battery.
Date: June 1, 1995
Creator: Dudney, N.J.; Bates, J.B. & Lubben, D.
Partner: UNT Libraries Government Documents Department

Development of a lithium microbattery packaging technology: ERKTS01. Final report

Description: The objective of this joint project between Oak Ridge National Laboratory (ORNL) and Eveready Battery Company (EBC) was to develop a coating process that would protect the lithium anode of thin-film rechargeable lithium batteries from air. Several methods were investigated including metallization of the lithium film, coverage of the lithium anode with the electrolyte, lithium phosphorus oxynitride (Lipon), and other ceramic films, and a multilayer coating consisting of alternating films of parylene and metal and/or ceramic films. The parylene-ceramic or metal multilaver coating was found to be an effective packaging method for thin-film lithium batteries.
Date: October 1, 1995
Creator: Bates, J.B.; Yu, Xioahua; Luck, C.F. & Dudney, N.J.
Partner: UNT Libraries Government Documents Department

Plasma diagnostic studies of the influence of process variables upon the atomic and molecular species ejected from (1-x)Li sub 4 SiO sub 4 :xLi sub 3 PO sub 4 targets during rf-magnetron sputtering

Description: The deposition of thin-film electrolytes is a critical step in the development of lithium microbatteries with the potential for circuit integration. We have performed a preliminary study of the rf-magnetron sputtering of (1-x)Li{sub 4}SiO{sub 4}:xLi{sub 3}PO{sub 4} targets used to deposit amorphous thin-film electrolytes formed of the three-component system Li{sub 2}O--SiO{sub 2}--P{sub 2}O{sub 5}. Mass and optical emission spectroscopies have been used to investigate the effects of target composition and the deposition conditions upon the atomic and molecular species ejected from the targets. The data provide important information for understanding the mechanism of film formation and for monitoring the Li atomic flux onto the substrates during film growth. 5 refs., 7 figs., 1 tab.
Date: January 1, 1990
Creator: Wachs, A.L.; Bates, J.B.; Dudney, N.J. & Luck, C.F.
Partner: UNT Libraries Government Documents Department

5-Volt and 4.6 V plateaus in LiMn{sub 2}O{sub 4} thin films

Description: Additional plateaus with median voltages of {similar_to}4.6 V, and {similar_to}5 V have been observed on charging thin film lithium batteries with crystalline LiMn{sub 2}O{sub 4} cathodes to 5.3 V. Total charge extracted from the 4 V and the two additional plateaus corresponded to about 1Li/Mn{sub 2}O{sub 4}, but the distribution of capacity among the three plateaus varied from film to film. It is speculated that the additional plateaus result from formation of mixed spinel structures in which a fraction of the 8a sites areoccupied by Mn{sup 2+} or Mn{sup 4+} ions and a fraction of the Li{sup +} ions occupy the 16d sites. After charging to 5.3 V, the 4.6 V plateau disappeared, and the capacity of the 4 V plateau increased at the expense of that of the 5 V plateau. The latter change is attributed to movement of Mn{sup 3+} or Mn{sup 5+} ions from 8a to 16d sites.
Date: January 1, 1996
Creator: Bates, J.B.; Lubben, D.; Dudney, N.J.; Zuhr, R.A. & Hart, F.X.
Partner: UNT Libraries Government Documents Department

Hysteresis in Thin-Film Rechargeable Lithium Batteries

Description: Discharge - charge cycling of thin-film rechargeable lithium batteries with an amorphous or nanocrystalline LiXMn2.Y04 cathode reveals evidence for a true hysteresis in the lithium insertion reaction. This is compared with an apparent hysteresis attributed to a kinetically hindered phase transition near 3 V for batteries with either a crystalline or a nanocrystalline LiJ@Yo4 cathode.
Date: April 25, 1999
Creator: Bates, J.B.; Dudney, N.J.; Evans, C.D. & Hart, F.X.
Partner: UNT Libraries Government Documents Department

Sputter deposition of lithium silicate - lithium phosphate amorphous electrolytes

Description: Thin films of an amorphous lithium-conducting electrolyte were deposited by rf magnetron sputtering of ceramic targets containing Li{sub 4}SiO{sub 4} and Li{sub 3}PO{sub 4}. The lithium content of the films was found to depend more strongly on the nature and composition of the targets than on many other sputtering parameters. For targets containing Li{sub 4}SiO{sub 4}, most of the lithium was found to segregate away from the sputtered area of the target. Codeposition using two sputter sources achieves a high lithium content in a controlled and reproducible film growth. 10 refs., 4 figs.
Date: January 1, 1991
Creator: Dudney, N.J.; Bates, J.B.; Luck, C.F. (Oak Ridge National Lab., TN (USA)) & Robertson, J.D. (Kentucky Univ., Lexington, KY (USA). Dept. of Chemistry)
Partner: UNT Libraries Government Documents Department

Thin film amorphous electrolytes: The Li sub 2 O-SiO sub 2 -P sub 2 O sub 5 system

Description: Thin film amorphous electrolytes with compositions xLi{sub 2}O: ySiO{sub 2}:zP{sub 2}O{sub 5} were deposited by single and dual source rf magnetron sputtering and their compositions determined by electron and ion beam techniques. Films containing P but no Si were composed of mainly orthophosphate and some linear chain phosphate anions, whereas single phase films containing Si and P were evidently composed of branched and possible cyclic and extended network structures. Films with Si/P>1 appeared to contain two or more amorphous phases. In the range of compositions investigated, the lithium ion conductivity depends mainly on the lithium ion mobility which is sensitive to the structure of the films. An open circuit voltage from 1 to 3 V measured between blocking metal contacts on the electrolyte thin films suggest that the films might be electrets. 18 refs., 5 figs., 2 tabs.
Date: January 1, 1991
Creator: Bates, J.B.; Dudney, N.J.; Sales, B.C.; Zuhr, R.A.; Gruzalski, G.R.; Luck, C.F. (Oak Ridge National Lab., TN (USA)) et al.
Partner: UNT Libraries Government Documents Department