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Lithium-rich, layered composites of xLi 2 MnO 3 • (1−x)Li(Ni 1/3 Mn 1/3 Co 1/3 )O 2 were synthesized via spray pyrolysis to identify the chemistry yielding optimal electrochemical performance for materials produced by this method. The x values selected for optimization were x = 0.

Lithium-rich, layered composites of xLi 2 MnO 3 •(1-x)LiNi 1/3 Mn 1/3 Co 1/3 O 2 have been extensively studied for PHEVs and EVs. To ensure complete lithiation, most synthesis methods require the addition of excess lithium compared to the stoichiometric composition. In this study lithium enriched, layered composites of Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 were synthesized in a spray pyrolysis process. Spray pyrolysis allows for excellent control of composition and in this work the lithium content was systematically varied between 3.3 wt% excess and 3.3 wt% deficient compared to Li 1.2 Mn 0.54 Ni 0.13 Co 0.13 O 2 . The as-synthesized powders were annealed at 900 • C for 2, 5 and 20 hours. Results indicate that as the annealing time is increased the surface areas is reduced from 9 to ∼2 m 2 g −1 .No new phases form during the annealing process although changes in the relative intensity of the ( 018) and ( 110) peaks imply a reorganization between the transition metal and lithium layers. An excess Li of 3.3 wt% is sufficient to counter these structural rearrangements and maintain discharge capacities close to 200 mAhg −1 after 100 cycles at C/3. Samples with a smaller surface area do not lead to improved capacity retention. The results also suggest that the Li 2 MnO 3 structural component has a key role in the voltage fade for these materials.

ABS":PQFF packages, prior to board assembly, have a requirement to be "Baked Out7' of absorbed moisture to prevent 'Pop Corning'. This paper identifies key factors that are necessary for ,cont.roIling an efficient and optimized Bake Out process. Moisture absorption and desorption of the PQFP package will be discussed. Methods will be recommended for optimizing and verifying the performance of the Bake Out ovens. blTRODUCIION :The intent of this paper is to present techniques to reduce the bake out process time for PQFP packages. The results of this report are based on using 20,28 and 32 mm sq body sizes.Generally, a high pin count plastic package (160,208,240 PQFP) with a moisture level at or below 0.05% by dry weight is considered dry enough for dry packing. These components are dried below the required safe moisture level to endure a specified time for shipping, handling and storage in a humid environment before the componexlts are mounted in the printed wiring board [I].This paper will address the question how long will it take to bake out a package such that the moisture content witbin the package is effectively &ied to 0.05% of its dry weight. One of the most effective ways to keep the bake out time short is to control the amount of dme a package is exposed to moisture prior to bake out. To insure that this is met within our process, the moisture level targeted for the package was driven to 60 % less than 0.05% by dry weight package as a safety margin. Using this as a guidebe, our cumnt process has successfully shipped without any "pop com" defects. The peak temperature of the solder reflow at board attach is 240 degree C. The bake out time used for achieving this was from a minimum of four hours to a maximum of eight hours by optimizing the key elements mentioned above. BACKGROUND: