Positive electrode active material for lithium ion batteries, positive electrode for lithium ion batteries, and lithium ion battery
View Patent ↗The present invention provides a positive electrode active material for lithium ion batteries having satisfactory battery characteristics. The positive electrode active material for lithium ion batteries, is represented by the following composition formula: Li(Li x Ni 1-x-y M y )O 2+α wherein M represents one or more selected from the group consisting of scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), copper (Cu), zinc (Zn), gallium (Ga), germanium (Ge), bismuth (Bi), tin (Sn), magnesium (Mg), calcium (Ca), boron (B) and zirconium (Zr); 0≦x≦0.1; 0<y≦0.7; and α>0, wherein the particle size of primary particles is 1.6 to 2.3 μm, the alkali amount at the particle surfaces measured by two-stage neutralization titration is 1.2% by mass or less, and when the amount of lithium hydroxide in the alkali amount at the particle surfaces is designated as A % by mass, and the amount of lithium carbonate is designated as B % by mass, the ratio A/B is 1 or less.
1. A positive electrode active material for lithium ion batteries, represented by the following composition formula:
Li(Li x Ni 1-x-y M y )O 2+α
wherein M represents one or more selected from the group consisting of scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), copper (Cu), zinc (Zn), gallium (Ga), germanium (Ge), bismuth (Bi), tin (Sn), magnesium (Mg), calcium (Ca), boron (B) and zirconium (Zr); 0≦x≦0.1; 0<y≦0.7; and α>0,
wherein the particle size of primary particles is 1.6 to 2.3 μm,
the alkali amount at the particle surfaces measured by two-stage neutralization titration is 1.2% by mass or less, and
when the amount of lithium hydroxide in the alkali amount at the particle surfaces is designated as A % by mass, and the amount of lithium carbonate is designated as B % by mass, the ratio A/B is 1 or less.
2. The positive electrode active material for lithium ion batteries according to claim 1 , wherein the alkali amount at the particle surfaces is 0.8% by mass or less.
3. The positive electrode active material for lithium ion batteries according to claim 2 , wherein the ratio A/B is 0.7 or less.
4. The positive electrode active material for lithium ion batteries according to claim 2 , wherein M is one or more selected from Mn and Co.
5. The positive electrode active material for lithium ion batteries according to claim 2 , wherein in the composition formula, α>0.05.
6. The positive electrode active material for lithium ion batteries according to claim 5 , wherein in the composition formula, α>0.1.
7. A positive electrode for lithium ion batteries, using the positive electrode active material for lithium ion batteries according to claim 2 .
8. The positive electrode active material for lithium ion batteries according to claim 1 , wherein the ratio A/B is 0.7 or less.
9. The positive electrode active material for lithium ion batteries according to claim 1 , wherein M is one or more selected from Mn and Co.
10. The positive electrode active material for lithium ion batteries according to claim 1 , wherein in the composition formula, α>0.05.
11. The positive electrode active material for lithium ion batteries according to claim 10 , wherein in the composition formula, α>0.1.
12. A positive electrode for lithium ion batteries, using the positive electrode active material for lithium ion batteries according to claim 1 .
13. A lithium ion battery using the positive electrode for lithium ion batteries according to claim 12 .
14. A lithium ion battery using the positive electrode for lithium ion batteries according to claim 7 .