| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a positive electrode active material suitably available for a secondary battery, especially a sodium secondary battery by suppressing the necessity for sieving out, and to provide a powder for the positive electrode active material as a raw material. <P>SOLUTION: The powder for the positive electrode active material is made of particles containing Mn. In the volume-based cumulative particle size distribution of the particles constituting the powder, the particle diameter (D50) at 50% cumulation when viewed from the particulate side is in a range of ≥0.1 μm and ≤10 μm, ≥90% by volume of the particles constituting the powder have a particle size of ≥0.3 times and ≤3 times of the D50 value. The powder for the positive electrode active material is made of the particles containing Mn and ≥90% by volume of the particles constituting the powder have a particle size of ≥0.6 μm and ≤6 μm. A powdery positive electrode active material is obtained by calcinating a mixture of the powder for the positive electrode active material and a sodium compound. The positive electrode for the sodium secondary battery contains the positive electrode active material. <P>COPYRIGHT: (C)2009,JPO&INPIT |
