Positive electrode active material for magnesium secondary battery, positive electrode for magnesium secondary battery, and magnesium secondary battery
A positive electrode active material for a magnesium secondary battery, and a positive electrode for a magnesium secondary battery and a magnesium secondary battery in which the positive electrode active material is used are provided. The positive electrode active material consists of a magnesium composite oxide which is represented by Formula (1): Mg x M1 y M2 z O 2 and which has a rock salt-type crystal structure of space group Fm-3m. In Formula (1), M1 is Ni, Co, or Mn, M2 is different from M1 and is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, Cu, Nb, W, Mo, and Ru, 0<x≤1, 0<y<2, 0<z<1; and 1.5≤x+y+z≤2.0.
1. A positive electrode active material for a magnesium secondary battery, the positive electrode active material consisting of a magnesium composite oxide that is represented by the following Formula (1) and that has a rock salt-type crystal structure of space group Fm-3m:
Mg x M1 y M2 z O 2 (1)
wherein, in Formula (1), M1 is Ni, Co, or Mn;
M2 is different from M1 and is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, Cu, Nb, W, Mo, and Ru;
0<x≤1;
0<y<2;
0<z<1; and
1.5≤x+y+z≤2.0.
2. The positive electrode active material for a magnesium secondary battery according to claim 1 , wherein M1 in Formula (1) is Ni.
3. The positive electrode active material for a magnesium secondary battery according to claim 1 , wherein M2 in Formula (1) is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, and Cu.
4. The positive electrode active material for a magnesium secondary battery according to claim 1 , wherein 0<x≤0.8, 0.5≤y<2, 0<z≤0.6, and 1.5≤x+y+z≤2.0.
5. A positive electrode for a magnesium secondary battery, the positive electrode comprising the positive electrode active material for a magnesium secondary battery according to claim 1 .
6. A magnesium secondary battery, comprising:
the positive electrode for a magnesium secondary battery according to claim 5 ;
a negative electrode; and
a non-aqueous electrolyte solution.
7. The positive electrode active material for a magnesium secondary battery according to claim 1 , wherein in Formula (1):
M1 is Ni; and
M2 is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, and Cu.
8. The positive electrode active material for a magnesium secondary battery according to claim 1 , wherein in Formula (1):
M1 is Ni;
M2 is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, and Cu;
0<x≤0.8;
0.5≤y<2;
0<z≤0.6; and
1.5≤x+y+z≤2.0.
9. The positive electrode for a magnesium secondary battery according to claim 5 , wherein in Formula (1):
M1 is Ni; and
M2 is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, and Cu.
10. The positive electrode for a magnesium secondary battery according to claim 5 , wherein in Formula (1):
M1 is Ni;
M2 is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, and Cu;
0<x≤0.8;
0.5≤y<2;
0<z≤0.6; and
1.5≤x+y+z≤2.0.
11. The magnesium secondary battery according to claim 6 , wherein in Formula (1):
M1 is Ni; and
M2 is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, and Cu.
12. The magnesium secondary battery according to claim 6 , wherein in Formula (1):
M1 is Ni;
M2 is at least one element selected from the group consisting of Ni, Co, Mn, Ti, V, Cr, Fe, and Cu;
0<x≤0.8;
0.5≤y<2;
0<z≤0.6; and
1.5≤x+y+z≤2.0.