Negative-electrode material, negative-electrode active material, negative electrode, and alkali metal ion battery

摘要

A negative-electrode material is a carbonaceous negative-electrode material used in an alkali metal ion battery and an average layer spacing d 002 of face (002) calculated by an X-ray diffraction method using CuK± radiation as a radiation source is equal to or more than 0.340 nm. When the negative-electrode material is embedded in an epoxy resin, the epoxy resin is cured, the resultant cured material is cut and polished to expose a cross-section of the negative-electrode material, and the cross-section is observed in a bright field with 1000 times magnification using an optical microscope, a first region (101) and a second region (103) having different reflectance ratios are observed from the cross-section of the negative-electrode material (100).