The LCO sintered plate was polished with a cross section polisher (CP) (IB-15000CP, manufactured by JEOL Ltd.), and the resultant cross-section of the positive electrode plate (cross-section perpendicular to the plate face of the positive electrode plate) was subjected to the EBSD measurement at a 1000-fold field of view (125 μm×125 μm) to give an EBSD image. This EBSD measurement was performed using a Schottky field emission scanning electron microscope (model JSM-7800F, manufactured by JEOL Ltd.). For all grains identified in the resultant EBSD image, the angles defined by the (003) planes of the primary grains and the plate face of the positive electrode plate (that is, the tilt of the crystal orientation from the (003) planes) is determined as a tilt angle. The mean value of the angles was determined as an average orientation angle of the primary grains.

<Thickness>

The LCO or LTO sintered plate was polished with a cross-section polisher (CP) (IB-15000CP, manufactured by JEOL Ltd.), and the resultant cross section of the positive electrode plate was observed with SEM (JSM6390LA, manufactured by JEOL Ltd.) to determine the thickness of the positive electrode plate. The thickness of the dried LCO or LTO green sheet described above in Procedures (1a) and (2a) was also determined in the same manner.

<Porosity>

The LCO or LTO sintered plate was polished with a cross-section polisher (CP) (IB-15000CP, manufactured by JEOL Ltd.), and the resultant cross section of the positive electrode plate was observed with SEM (JSM6390LA, manufactured by JEOL Ltd.) at a 1000-fold field of view (125 μm×125 μm). The SEM image was subjected to an image analysis, the area of all pores was divided by the area of the positive electrode, and the resultant value was multiplied by 100 to calculate the porosity (%).