Electrode for a secondary battery, secondary battery, battery pack and vehicle

1. An electrode for a secondary battery, comprising:

a current collector; and

an active material-containing layer comprising active materials which comprise titanium-containing composite oxide having an orthorhombic crystal structure and a formula Li 2+a M1 2−b Ti 6−c M2 d O 14+δ ,

wherein the Li 2+a M1 2−b Ti 6−c M2 d O 14+5 in the active material-containing layer has an intensity ratio Ia/Ib in an X-ray diffraction pattern of the active material-containing layer, the Ia and the Ib being obtained by powder X-ray diffraction method using Cu-Kα ray, the intensity ratio being in a range of 0.5≤Ia/Ib≤2, the Ia being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 42° ≤20≤44°, and the Ib being the strongest intensity of a diffraction peak among different peaks appearing in a range of 44° <20≤48°, and

wherein

M1 is at least one selected from the group consisting of Sr, Ba, Ca, Mg, Na, Cs, Kb, and K,

M2 is at least one selected from the group consisting of Zr, Sn, V, Nb, Ta, Mo, Fe, Co, Cr, Mn, Ni, and Al,

a is in a range of 0≤a≤6,

b is in a range of 0≤b<2,

c is in a range of 0≤c<6,

d is in a range of 0≤d<6, and

δ is in a range of −0.5≤δ≤0.5.

2. The electrode of claim 1 , wherein the intensity ratio Ia/Ib is in a range of 0.8≤Ia/Ib≤1.2.

3. The electrode claim 1 , wherein the titanium-containing composite oxide is a space group Cmca and/or a space group Fmmm.

4. The electrode of claim 1 , wherein the active material has a particle shape and at least one part of the active material surface comprises a carbon containing layer.

5. A secondary battery, comprising;

a positive electrode;

a negative electrode; and

an electrolyte,

wherein the negative electrode is the electrode comprising a current collector and an active material-containing layer comprising active materials which comprise titanium-containing composite oxide having an orthorhombic crystal structure and a formula Li 2+a M1 2−b Ti 6−c M2 d O 14+δ ,

wherein the Li 2+a M1 2−b Ti 6−c M2 d O 14+δ , in the active material-containing layer has an intensity ratio Ia/Ib in an X-ray diffraction pattern of the active material-containing layer, the Ia and the Ib being obtained by powder X-ray diffraction method using Cu-Kα ray, the intensity ratio being in a range of 0.5≤Ia/Ib≤2, the Ia being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 42° ≤20≤44°, and the Ib being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 44° <20≤48°, and

wherein

M1 is at least one selected from the group consisting of Sr, Ba, Ca, Mg, Na, Cs, Rb, and K,

M2 is at least one selected from the group consisting of Zr, Sn, V, Nb, Ta, Mo, V, Y, Fe, Co, Cr, Mn, Ni, and Al,

a is in a range of 0≤a≤6,

b is in a range of 0≤b<2,

c is in a range of 0≤c<6,

d is in a range of 0≤d<6, and

δ is in a range of −0.5≤δ≤0.5.

6. The secondary battery of 5 , wherein the positive electrode comprise positive active materials which are at least one selected from the group consisting of LiFePO 4 , LiMnPO 4 , LiMn 1−x Fe x PO 4 (0<×≤0.5), LiFeSO 4 F, LiNi s Co t Mn 1−s−t O 2 , (0<s<1, 0<t<1, and 0<( 1 −s−t)<1), LiMn 2 O 4 , and LiMn 1,5 Ni 0.5 O 4 .

7. A secondary battery, comprising:

a positive electrode;

a negative electrode; and

an electrolyte,

wherein the positive electrode is the electrode comprising a current collector and an active material-containing layer comprising active materials which comprise titanium-containing composite oxide having an orthorhombic crystal structure and a formula Li 2+a M1 2−b Ti 6−c M2 d O 14+δ ,

wherein the Li 2+a M1 2−b Ti 6−c M2 d O 14+δ in the active material-containing layer has an intensity ratio Ia/Ib in an X-ray diffraction pattern of the active material-containing layer, the Ia and the Ib being obtained by powder X-ray diffraction method using Cu-Kα ray, the intensity ratio being in a range of 0.5≤Ia/Ib≤2, the Ia being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 42° ≤20≤44°, and the Ib being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 44° <20≤48°, and

wherein

M1 is at least one selected from the group consisting of Sr, Ba, Ca, Mg, Na, Cs, Rb, and K,

M2 is at least one selected from the group consisting of Zr, Sn, V, Nb, Ta, Mo, W, Y, Fe, Co, Cr, Mn, Ni, and Al,

a is in a range of 0≤a≤6,

b is in a range of 0≤b<2,

c is in a range of 0≤c<6,

d is in a range of 0≤d<6, and

δ is in a range of −0.5≤δ≤0.5.

8. A battery pack, comprising:

a plurality of secondary batteries comprising a positive electrode, a negative electrode and an electrolyte,

wherein at least one of the positive electrode and the negative electrode is the electrode comprising a current collector and an active material-containing layer comprising active materials which comprise titanium-containing composite oxide having an orthorhombic crystal structure and a formula Li 2+a M1 2−b Ti 6−c M2 d O 14+δ ,

wherein the Li 2+a M1 2−b Ti 6−c M2 d O 14+δ in the active material-containing layer has an intensity ratio Ia/Ib in an X-ray diffraction pattern of the active material-containing layer, the Ia and the Ib being obtained by powder X-ray diffraction method using Cu-Kα ray, the intensity ratio being in a range of 0.5≤Ia/Ib≤2, the Ia being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 42° ≤20≤44°, and the Ib being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 44° <20≤48°, and

wherein

M1 is at least one selected from the group consisting of Sr, Ba, Ca, Mg, Na, Cs, Rb, and K,

M2 is at least one selected from the group consisting of Zr, Sn, V, Nb, Ta, Mo, W, Y, Fe, Co, Cr, Mn, Ni, and Al,

a is in a range of 0≤a≤6,

b is in a range of 0≤b<2,

c is in a range of 0≤c<6,

d is in a range of 0≤d<6, and

δ is in a range of −0.5≤δ≤0.5.

9. The pack of claim 8 , further comprising:

an external terminal configured for energization and a protective circuit.

10. The pack of claim 9 , wherein the battery packs are connected electrically to each other in series, in parallel, or in a combination of series connection and parallel connection.

11. A vehicle, comprising:

a plurality of battery packs including a plurality of secondary batteries comprising a positive electrode, a negative electrode, and an electrolyte,

wherein at least one of the positive electrode and the negative electrode is the electrode comprising a current collector and an active material-containing layer comprising active materials which comprise titanium-containing composite oxide having an orthorhombic crystal structure and a formula Li 2+a M1 2−b Ti 6−c M2 d O 14+δ ,

wherein the Li 2+a M1 2−b Ti 6−c M2 d O 14+δ in the active material-containing layer has an intensity ratio Ia/Ib in an X-ray diffraction pattern of the active material-containing layer, the Ia and the Ib being obtained by powder X-ray diffraction method using Cu-Kα ray, the intensity ratio being in a range of 0.5≤Ia/Ib≤2, the Ia being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 42° ≤20≤44°, and the Ib being the strongest intensity of a diffraction peak among diffraction peaks appearing in a range of 44° <20≤48°, wherein

M1 is at least one selected from the group consisting of Sr, Ba, Ca, Mg, Na, Cs, Rb, and K,

M2 is at least one selected from the group consisting of Zr, Sn, V, Nb, Ta, Mo, W, Y, Fe, Co, Cr, Mn, Ni, and Al,

a is in a range of 0≤a≤6,

b is in a range of 0≤b<2,

c is in a range of 0≤c<6,

d is in a range of 0≤d<6, and

δ is in a range of −0.5≤δ≤0.5.

12. The vehicle of claim 11 , further comprising:

a mechanism configured to convert kinetic energy of the vehicle into regenerative energy.

13. The secondary battery of claim 5 , wherein the intensity ratio Ia/Ib is in a range of 0.8≤Ia/Ib≤1.2.

14. The secondary battery of claim 7 , wherein the intensity ratio Ia/Ib is in a range of 0.8≤Ia/Ib≤1.2.

15. The pack of claim 8 , wherein the intensity ratio Ia/Ib is in a range of 0.8≤Ia/Ib≤1.2.

16. The vehicle of claim 11 , wherein the intensity ratio Ia/Ib is in a range of 0.8≤Ia/Ib≤1.2.

17. The electrode of claim 1 , wherein the intensity ratio Ia/Ib is in within a range of 0.85≤Ia/Ib≤2.0.

18. The secondary battery of claim 5 , wherein the intensity ratio Ia/Ib is in a range of 0.85≤Ia/Ib≤2.0.

19. The secondary battery of claim 7 , wherein the intensity ratio Ia/Ib is in within a range of 0.85≤Ia/Ib≤2.0.

20. The electrode of claim 1 , wherein M1 is at least one selected from the group consisting of Sr, Ca, Mg, Cs, Rb, and K.