Lithium ion secondary battery
View Patent ↗A lithium ion secondary battery includes a positive electrode including a positive electrode active material having a composition represented by the formula (1) Li x Ni y Co z M t O 2 (1) (wherein the element M is at least one kind selected from the group consisting of Mg, Ba, Al, Ti, Mn, V, Fe, Zr, and Mo and x, y, z, and t satisfy the following formulae: 0.9≦x≦1.2, 0≦y≦1.1, 0≦z≦1.1, and 0≦t≦1.1), and a negative electrode including a negative electrode active material mainly containing silicon and silicon oxide, and having an absorbance of 0.01 to 0.035 at 2110±10 cm −1 according to an FT-IR method.
1. A lithium ion secondary battery comprising:
a positive electrode including a positive electrode active material having a composition represented by formula (1) below; and
a negative electrode including a negative electrode active material mainly containing silicon and silicon oxide, and having an absorbance of 0.01 to 0.035 at 2110±10 cm −1 according to an FT-IR method:
Li x Ni y Co z M t O 2 (1)
wherein;
M is at least one element selected from the group consisting of Mg, Ba, Al, Ti, Mn, V, Fe, Zr, and Mo; and
x, y, z, and t satisfy the following formulae:
0.9≦x≦1.2,
0≦y≦1.1,
0≦z≦1.1, and
0≦t≦1.1.
2. The lithium ion secondary battery according to claim 1 , wherein:
y=0;
0.0≦z≦1.1; and
t=0.
3. The lithium ion secondary battery according to claim 1 , wherein the M is Mn.
4. The lithium ion secondary battery according to claim 1 , wherein the M is Al.
5. The lithium ion secondary battery according to claim 1 , wherein a ratio of the total mass of the negative electrode active material to a sum of the mass of silicon and the mass of silicon oxide is 95 mass % or more.
6. The lithium ion secondary battery according to claim 1 , wherein the negative electrode active material is covered with amorphous carbon.