CPC H01M 10/0525 (2013.01) [H01M 4/364 (2013.01); H01M 4/505 (2013.01); H01M 4/525 (2013.01); H01M 10/0567 (2013.01); H01M 10/0569 (2013.01); H01M 50/46 (2021.01); H01M 2004/027 (2013.01); H01M 2004/028 (2013.01); H01M 2300/0034 (2013.01); H01M 2300/0051 (2013.01)] | 13 Claims |
1. A lithium secondary battery comprising:
a positive electrode comprising a first lithium-metal oxide comprising secondary particles formed by aggregating primary particles having a particle diameter of less than 2 μm, and a second lithium-metal oxide comprising nickel and at least one or more metals selected from the group consisting of manganese and cobalt and comprising primary particles having a particle diameter of 2 μm or more;
a negative electrode;
a separator interposed between the positive electrode and the negative electrode; and
an electrolyte comprising a lithium salt, a nonaqueous organic solvent, and a compound containing at least one or more difluorophosphite groups,
wherein the compound containing at least one or more difluorophosphite groups is the following Chemical Formula 2 or Chemical Formula 3:
wherein
R is hydrogen, cyano, or H—(CH2CH2O)m—; and
n is an integer of 2 to 8 and m is an integer of 1 or 2,
wherein
p is an integer of 1 to 3.
|