Laminate, secondary battery, battery pack, and vehicle
A laminate that includes an active material layer including a plural of active material particles, a separator layered on the active material layer, and an organic electrolyte. The separator includes a first surface and a second surface opposed to the first surface, and includes particles containing an inorganic compound having lithium ion conductivity at 25° C. of 1×10 −10 S/cm or more, and a ratio (L/R max ) of a thickness L to a radius R max is greater than zero and less than or equal to five, where L and R max are defined in the application.
1. A laminate comprising:
an active material layer that comprises a plural of active material particles;
a separator that is layered on the active material layer, and comprises a first surface and a second surface opposed to the first surface; and
an organic electrolyte,
wherein the separator comprises particles comprising an inorganic compound having lithium ion conductivity at 25° C. of 1×10 −10 S/cm or more, and a ratio (L/R max ) of a thickness L to a radius R max satisfies 0<L/R max ≤5,
where the radius R max is a radius of the active material particle having a maximum particle size among the active material particles facing the first surface of the separator, and the thickness L is distance from an interface between the active material particle having a maximum particle size and the first surface of the separator to the second surface of the separator,
and wherein a ratio of an amount of the organic electrolyte to a total amount of the particles and the organic electrolyte is within a range of 1% by mass to 10% by mass.
2. The laminate according to claim 1 , wherein the inorganic compound has a garnet structure.
3. The laminate according to claim 1 , wherein an average particle size of the particles is smaller than an average particle size of the active material particles.
4. The laminate according to claim 1 , wherein the ratio (L/R max ) is 2 or less.
5. The laminate according to claim 1 , wherein the ratio (L/R max ) is 1 or less.
6. The laminate according to claim 1 , wherein the ratio (L/R max ) is 0.8 or less.
7. The laminate according to claim 1 , wherein the ratio (L/R max ) is within a range of 0.001 to 0.33.
8. The laminate according to claim 1 , wherein the average particle size of the particles is 1 μm or less.
9. The laminate according to claim 1 , wherein the organic electrolyte comprises at least one selected from the group consisting of propylene carbonate, ethylene carbonate, diethyl carbonate, and methylethyl carbonate.
10. A secondary battery comprising the laminate according to claim 1 .
11. A battery pack comprising the secondary battery according to claim 10 .
12. The battery pack according to claim 11 , further comprising:
an external power distribution terminal; and
a protective circuit.
13. The battery pack according to claim 11 , comprising a plural of the secondary batteries, wherein the secondary batteries are electrically connected in series, in parallel, or in a combination of in series and in parallel.
14. A vehicle comprising the battery pack according to claim 11 .
15. The vehicle according to claim 14 , wherein the battery pack is configured to recover regenerative energy caused by power of the vehicle.