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Higher energy density batteries continue to be pursued by researchers. One general route to increase energy density is to increase electrode thickness, which reduces the relative fraction of the cell allocated to inactive components. One route to fabricate thick electrodes is to use mildly thermally treated, or sintered, electrodes comprising only electroactive materials. In this report, the concept of sintered electrodes comprising two different electroactive components will be reported. Conventional composite electrodes with multiple electroactive materials have previously been investigated with the goal of combining desirable attributes of the different components. Sintered electrodes have additional complexity relative to composite electrodes in that interfaces can be formed during processing, and consideration of the location of the different component materials must be taken into account due to the need for electronic conduction through the electrode matrix to proceed through the electroactive materials themselves. Both additional considerations and outcomes will be discussed in this report where multicomponent sintered electrodes of LiCoO 2 and LiMn 2 O 4 were fabricated and characterized. 

This study provides insights into the influence of sucrose (a water-soluble additive) on microstructure evolution in the transition region and steady-state region in ice-templated Li4Ti5O12 materials. A scanning electron microscope was employed for the two-dimensional characterization of microstructure in the transition region. Sucrose reduced the height of the transition region, caused an early alignment of ice lamellae toward temperature gradient direction, and resulted in a fine, dendritic microstructure. The overall microstructure development in the transition region was markedly different with and without sucrose. The differences were rationalized based on thermal conductivity, constitutional supercooling, and instability of the planar interface. Three-dimensional characterization of the steady-state region using X-ray computed tomography revealed that sucrose caused increased branching of the primary ice dendrites through tip splitting. A majority of the secondary dendrites turned into neighboring primary dendrites, enhancing pore path complexity. Diffusion simulations were performed to quantify pore tortuosity, which increased with sucrose content.