Electrode, battery and battery pack
According to one embodiment, an electrode is provided. The electrode includes an active material-containing layer. The active material-containing layer includes active material particles, a first electro-conductive agent having a fibrous shape, and a second electro-conductive agent having a shape other than the fibrous shape. The active material particles include at least one compound selected from the group consisting of a monoclinic titanium-containing oxide and an orthorhombic titanium-containing composite oxide. The active material-containing layer satisfies formula (1): 0.6≤B/A≤1.5. A is a thickness [μm] of the active material-containing layer. B is a maximum length [μm] of the first electro-conductive agent in the active material-containing layer.
1 . An electrode comprising:
a current collector; and
an active material-containing layer on a surface of the current collector,
the active material-containing layer comprising:
active material particles, the active material particles comprising at least one compound selected from the group consisting of a monoclinic titanium-containing oxide and an orthorhombic titanium-containing composite oxide;
a first electro-conductive agent having a fibrous shape; and
a second electro-conductive agent having a shape other than the fibrous shape,
the active material-containing layer satisfying formula (1): 0.6≤B/A≤1.5,
where A is a thickness [μm] of the active material-containing layer, and B is a maximum length [μm] of the first electro-conductive agent in the active material-containing layer.
2 . The electrode according to claim 1 , wherein
the at least one compound comprises the monoclinic titanium-containing oxide, and
the monoclinic titanium-containing oxide comprises a monoclinic niobium-titanium composite oxide.
3 . The electrode according to claim 1 , wherein the first electro-conductive agent comprises at least one selected from the group consisting of a carbon nanotube and a carbon nanofiber.
4 . The electrode according to claim 1 , wherein the second electro-conductive agent comprises at least one selected from the group consisting of carbon black, graphite, graphene, and hard carbon.
5 . The electrode according to claim 1 , wherein the active material-containing layer further comprises a binder,
the binder comprising at least one selected from the group consisting of styrene butadiene rubber, acrylic acid, and carboxymethyl cellulose.
6 . The electrode according to claim 1 , wherein the thickness A of the active material-containing layer is from 25 μm to 70 μm.
7 . The electrode according to claim 1 , wherein the active material particles, the first electro-conductive agent, and the second electro-conductive agent are in a dispersed state within the active material-containing layer.
8 . The electrode according to claim 1 , wherein the active material-containing layer further comprises a binder, and
the active material-containing layer comprises from 86% by mass to 92% by mass of the active material particles, from 0.5% by mass to 5% by mass of the first electro-conductive agent, from 2% by mass to 7% by mass of the second electro-conductive agent, and from 2% by mass to 6% by mass of the binder.
9 . A battery comprising:
the electrode according to claim 1 as a negative electrode;
a positive electrode; and
an electrolyte.
10 . A battery pack comprising the battery according to claim 9 .