NOVELTY - A lithium metal complex oxide (I) has layered structure, specific surface area of more than 2 m2/g to 5 m2/g or less, and ratio of average particle diameter and crystalline diameter of primary particles of 5.7-18.5. The crystalline diameter of primary particles is calculated by measuring crystalline diameter of measurement sample (powder) using X-ray-diffraction apparatus with copper-K ( alpha ) x-ray, adopting fundamental parameter with diffraction angle (2 theta ) of 15-120 degrees , and computing crystalline diameter using software for analysis based on obtained X-ray-diffraction pattern.    USE - Lithium metal complex oxide is used as positive electrode active material for lithium cell (claimed) for electric vehicle, hybrid vehicle, video camera, notebook computer and mobile telephone.    ADVANTAGE - The lithium metal complex oxide has high specific surface area. The lithium cell containing the lithium metal complex oxide has suppressed rise of discharge capacity at high temperature, and fall of output characteristics, and excellent weather resistance and can also be used under various temperature environment.    DETAILED DESCRIPTION - A lithium metal complex oxide of formula: Li1+x(MnaCobNic)1-xO2 (I) has layered structure, specific surface area of more than 2 m2/g to 5 m2/g or less, and ratio of average particle diameter and crystalline diameter of primary particles of 5.7-18.5. The crystalline diameter of primary particles is calculated by measuring crystalline diameter of measurement sample (powder) using X-ray-diffraction apparatus with copper-K ( alpha ) x-ray, adopting fundamental parameter with diffraction angle (2 theta ) of 15-120 degrees , and computing crystalline diameter using software for analysis based on obtained X-ray-diffraction pattern. The average particle diameter of primary particles is calculated by observing particles using scanning electron microscope with acceleration voltage of 20 kV and 5000 times multiplication factor, and computing average particle diameter of primary particles using image-analysis software based on primary particles image of obtained electron micrograph.    x=0-0.07;    a=0.1-0.4;    b=0.1-0.4;and    c=0.3-0.75.    An INDEPENDENT CLAIM is included for lithium cell, which contains lithium metal complex oxide as a positive electrode active material.