ACTIVE MATERIAL PARTICLES AND USE OF SAME
Active material particles are provided that exhibit performance suitable for increasing the output of a lithium secondary battery and little deterioration due to charge-discharge cycling. The active material particles provided by the present invention have a hollow structure having secondary particles including an aggregate of a plurality of primary particles of a lithium transition metal oxide, and a hollow portion formed inside the secondary particles, and through holes that penetrates to the hollow portion from the outside are formed in the secondary particles. BET specific surface area of the active material particles is 0.5 to 1.9 m 2 /g.
1 . Active material particles for a lithium secondary battery, wherein
the active material particles have a hollow structure having secondary particles including an aggregate of a plurality of primary particles of a lithium transition metal oxide and a hollow portion formed inside the secondary particles, the lithium transition metal oxide is a compound having a layered structure that contains nickel as a constituent element thereof,
through holes that penetrates to the hollow portion from the outside are formed in the secondary particles, and
BET specific surface area of the active material particles is from 0.5 to 1.9 m 2 /g.
2 . The active material particles according to claim 1 , wherein the opening width of the through hole is on average 0.01 μm or more.
3 . The active material particles according to claim 1 , wherein the average hardness of the active material particles, as obtained by measuring dynamic hardness under conditions of a loading speed of 0.5 mN/sec to 3 mN/sec using a flat diamond indenter having a diameter of 50 μm, is 0.5 MPa or more.
4 . The active material particles according to claim 1 , wherein the number of the through holes per particle of the active material particles is 1 to 20 on average.
5 . The active material particles according to claim 1 , wherein the average particle diameter is 3 μm to 10 μm.
6 . (canceled)
7 . The active material particles according to claim 1 , wherein the lithium transition metal oxide is a compound having a layered structure that contains nickel, cobalt and manganese as constituent elements.
8 . A lithium secondary battery comprising a positive electrode, a negative electrode and a non-aqueous electrolyte solution, wherein
at least one of the positive electrode and the negative electrode is an electrode containing a hollow active material having the active material particles according to claim 1 .
9 . The lithium secondary battery according to claim 8 , which is used as a driving power supply of a vehicle.
10 . A vehicle comprising the battery according to claim 8 .
11 . (canceled)
12 . (canceled)
13 . (canceled)