Abstract: A positive electrode active material precursor having a uniform particle size distribution and represented by Formula 1, wherein a percentage of fine powder with an average particle diameter (D50) of 1 ?m or less is generated when the positive electrode active material precursor is rolled at 2.5 kgf/cm2 is less than 1%, and an aspect ratio is 0.93 or more, and a method of preparing the positive electrode active material precursor [NixCoyM1zM2w](OH)2 ??[Formula 1] in Formula 1, 0.5?x<1, 0<y?0.5, 0<z?0.5, and 0?w?0.1, M1 includes at least one selected from the group consisting of Mn and Al, and M2 includes at least one selected from the group consisting of Zr, B, W, Mo, Cr, Nb, Mg, Hf, Ta, La, Ti, Sr, Ba, Ce, F, P, S, and Y. A method of preparing the positive electrode active material precursor is also provided.

Abstract: Provided is an electromagnetic chuck mounting structure capable of tightly and fixedly mounting an electromagnetic chuck on a table without fluctuation, having light weight, and making a low profile when an electromagnetic chuck is mounted on the table. The structure includes: a mounting groove recessed on an upper surface of the table and located inward of an edge of the table; a plurality of mounting holes formed at regular intervals on the mounting groove to fix the electromagnetic chucks to be mounted; and an adhesive filled and cured on the mounting groove and between the mounted electromagnetic chucks, wherein each of the electromagnetic chucks is fixedly fastened to each of the mounting holes by one fastening bolt, such that an upper surface of each electromagnetic chuck is aligned on a same plane with the upper surface of the table or protrudes from the upper surface of the table.

Abstract: Provided is an electromagnetic chuck mounting structure capable of tightly and fixedly mounting an electromagnetic chuck on a table without fluctuation, having light weight, and making a low profile when an electromagnetic chuck is mounted on the table. The structure includes: a mounting groove recessed on an upper surface of the table and located inward of an edge of the table; a plurality of mounting holes formed at regular intervals on the mounting groove to fix the electromagnetic chucks to be mounted; and an adhesive filled and cured on the mounting groove and between the mounted electromagnetic chucks, wherein each of the electromagnetic chucks is fixedly fastened to each of the mounting holes by one fastening bolt, such that an upper surface of each electromagnetic chuck is aligned on a same plane with the upper surface of the table or protrudes from the upper surface of the table.