In one illustrative embodiment, the method comprises providing a wafer, forming a plurality of die above the wafer, identifying a plurality of good die and at least one non-useful die from the plurality of die, and performing a test process on the at least one non-useful die but not on the good die. A mapping table in a main memory is divided into a plurality of sub-mapping tables according to logical address groups. The positive active material paste contains from about 0.