Negative electrode for nonaqueous electrolyte solution battery and nonaqueous electrolyte solution battery having the same
A negative electrode used for a nonaqueous electrolyte solution battery having nonaqueous electrolyte solution containing lithium ion includes a metal carbon composite material. The metal carbon composite material has a porous carbon material having cavities, and a metal material made of metal to reversibly store or emit lithium ion. The metal material is arranged on a surface of the porous carbon material including inner surfaces of the cavities. The porous carbon material has a mass of 1-65 mass % when the metal carbon composite material is defined to have a mass of 100 mass %.
1. A negative electrode used for a nonaqueous electrolyte solution battery having nonaqueous electrolyte solution containing lithium ion, the negative electrode comprising:
a metal carbon composite material including a porous carbon material and a metal material, the porous carbon material being made of carbon material having cavities, the metal material being made of metal to reversibly store or emit lithium ion, the metal material being arranged on a surface of the porous carbon material including inner surfaces of the cavities, wherein
the porous carbon material has a concentration of 1-65 mass % when the metal carbon composite material is defined to have a mass of 100 mass %,
the porous carbon material comprises a plurality of dendritic objects having a three-dimensional mesh structure,
the porous carbon material has a first pore having a first diameter and a second pore having a second diameter larger than the first diameter of the first pore,
the first pore is a pore defined on the dendritic object and the second pore is a cavity defined between the plurality of dendritic objects entangling with each other,
the first diameter is smaller than or equal to 10 nm,
the second diameter is in a range between 10 nm and 100 nm,
the metal material is arranged on an inner surface of the first pore and an inner surface of the second pore, and
the metal carbon composite material has a particle shape having a diameter in a range between 0.5 μm and 100 μm.
2. The negative electrode according to claim 1 , wherein
the metal material is made of at least a kind of metal selected from elements of Si, Ge, Sn, In, Sb, and Zn, an alloy containing at least a kind of metal selected from the elements, a metal oxide containing at least a kind of metal selected from the elements, or a compound containing at least one of the metal, the alloy and the metal oxide.
3. The negative electrode according to claim 1 , wherein
the metal material supported in the metal carbon composite material is made of at least a kind of metal selected from metal elements having melting point equal to or lower than 3500° C., an alloy containing at least a kind of metal selected from the metal elements, or a compound containing at least one of the metal and the alloy, and
the metal or the alloy forms an alloy phase with lithium at a temperature equal to or lower than 1500° C. in a phase diagram.
4. The negative electrode according to claim 1 , wherein
the metal material supported in the metal carbon composite material is selected from Sn, Si, Ag—Sn alloy, Sn—Ag—Sb alloy, Cu—Sn alloy, Ag—Ge alloy, Cu—Ge alloy, Sn oxide and Si oxide.
5. The negative electrode according to claim 1 , wherein
the porous carbon material has a tap density equal to or lower than 0.2 g/cm 3 .
6. The negative electrode according to claim 1 , wherein
the porous carbon material has a pore volume equal to or larger than 1.5 cm 3 /g when the pore volume is measured by using a BJH method.
7. The negative electrode according to claim 1 , wherein
the porous carbon material has an average pore diameter equal to or smaller than 7 nm when the average pore diameter is measured by using a BJH method.
8. The negative electrode according to claim 1 , wherein
the nonaqueous electrolyte solution battery is a lithium ion battery.
9. A nonaqueous electrolyte solution battery comprising the negative electrode according to claim 1 , a positive electrode and a nonaqueous electrolyte solution containing lithium ion.