Non-aqueous electrolyte secondary battery

• US 6,506,520 B1
• Filed: 09/21/2000
• Issued: 01/14/2003
• Est. Priority Date: 12/02/1998
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Shimamura, Harunari, Yoshizawa, Hiroshi, Inoue, Kaoru, Nitta, Yoshiaki, Koshina, Hizuru
• Primary Examiner(s): Ryan, Patrick
• Assistant Examiner(s): WILLS, MONIQUE M
• Application Number:
  US09/601,273
• Time in Patent Office: 845 Days
• Field of Search: 429/231.95, 429/218.1, 429/229, 252/182.1, 320/128
• US Class Current: 429/231.95
• CPC Class Codes: H01M 10/052 Li-accumulators
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 2004/027 Negative electrodes
• CPC Class Codes: H01M 4/02 Electrodes composed of, or comprising, active material
• CPC Class Codes: H01M 4/131 Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx
• CPC Class Codes: H01M 4/134 Electrodes based on metals, Si or alloys
• CPC Class Codes: H01M 4/362 Composites
• CPC Class Codes: H01M 4/366 as layered products
• CPC Class Codes: H01M 4/38 of elements or alloys
• CPC Class Codes: H01M 4/386 Silicon or alloys based on silicon
• CPC Class Codes: H01M 4/387 Tin or alloys based on tin
• CPC Class Codes: H01M 4/42 Alloys based on zinc
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A negative electrode is characterized by its composite particles constructed in such a manner that at least part of the surrounding surface of nuclear particles containing at least one of tin, silicon and zinc as a constituent element, is coated with a solid solution or an inter-metallic compound, which is composed of, the element included in the nuclear particles, and at least one other element except the elements included in the nuclear particles selected from a group comprising group 2 elements, transition elements, group 12 elements, group 13 elements and group 14 elements except carbon of the Periodic Table. The present invention is characterized that the lithium content of the nuclear particles of the composite particles is 40-95 atomic percent of the theoretical limit of lithium content of each constituent element of the nuclear particles. Further, the batteries are first charged at a constant current and upon reaching the predetermined voltage, are charged at a constant voltage. The current density during charging are set at not more than 5 mA/cm² as a in the area where the positive and negative electrodes face each other.

Claims

1. A non-aqueous electrolyte secondary battery comprising:

a positive electrode,

a negative electrode capable of intercalating and de-intercalating lithium,

a non-aqueous electrolyte solution, and

a separator or a solid electrolyte,

wherein;

said negative electrode comprises a plurality of composite particles,

each of said composite particles comprises a central portion comprising lithium and at least one element selected from the group consisting of tin, silicon and zinc; and

a coating at least partially around said central portion,

said coating comprising solid solution or an inter-metallic compound,

said solid solution or inter-metallic compound comprising a) said at least one element selected from the group consisting of tin, silicon and zinc, and b) at least one element selected from the group consisting of group 2 elements, transition elements, group 12 elements, group 13 elements and group 14 elements exclusive of carbon, and exclusive of said at least element selected from the group consisting of tin, silicon, and zinc;

wherein the lithium content of said central portion is 40-95 atomic percent of the theoretical lithium content limit of the central portion.

2. The non-aqueous electrolyte secondary battery of claim 1, wherein the lithium content of said central portion is 50-90 atomic percent of the theoretical lithium content limit of the central portion.

3. A non-aqueous electrolyte secondary battery comprising:

a positive electrode,

a negative electrode capable of intercalating and de-intercalating lithium, said negative electrode comprising a current collector,

a non-aqueous electrolyte solution, and

a separator or a solid electrolyte,

wherein;

said negative electrode comprises a plurality of composite particles,

each of said composite particles comprises a central portion comprising lithium and at least one element selected from the group consisting of tin, silicon and zinc; and

a coating at least partially around said central portion,

said coating comprising a solid solution or an inter-metallic compound;

said solid solution or inter-metallic compound comprising a) said at least one element selected from the group consisting of tin, silicon and zinc, and b) at least one element selected from the group consisting of group 2 elements, transition elements, group 12 elements, group 13 elements and group 14 elements exclusive of carbon, and exclusive of said at least element selected from the group consisting of tin, silicon, and zinc;

wherein the volume expansion of said negative electrode exclusive of the current collector is 110-200% when said negative electrode contains an amount of lithium which prevents deposit of lithium on said negative electrode.

11. The non-aqueous electrolyte secondary battery of claim 3, wherein the element selected from the group consisting of tin, silicon, and zinc is tin.

12. The non-aqueous electrolyte secondary battery of claim 3, wherein the element selected from the group consisting of tin, silicon, and zinc is silicon.

13. The non-aqueous electrolyte secondary battery of claim 3, wherein the element selected from the group consisting of tin, silicon, and zinc is zinc.

4. A method charging of a non-aqueous electrolyte secondary battery, said method comprising the steps of:

providing said battery, said battery comprising a positive electrode and a negative electrode;

wherein

the negative electrode comprises a plurality of composite particles each of said composite particle comprises a central portion comprising lithium and at least one element selected from the group consisting of tin, silicon and zinc; and

a coating at least partially around said central portion,

said coating comprising a solid solution or an inter-metallic compound,

said solid solution or inter-metallic compound a) said at least one element selected from the group consisting of tin, silicon and zinc, and b) at least one element selected from the group consisting of group 2 elements, transition elements, group 12 elements, group 13 elements and group 14 elements exclusive of carbon, and exclusive of said at least element selected from the group consisting of tin, silicon, and zinc;

charging said battery at a constant current until reaching a predetermined voltage, and

charging said battery at said predetermined voltage after reaching said predetermined voltage, said predetermined voltage producing a current;

wherein said constant current and said current produced by said predetermined voltage are at not more than 5 mA/cm2 current density at an area where said positive electrode and said negative electrodes face each other.

14. The method of claim 4, wherein the element selected from the group consisting of tin, silicon, and zinc is tin.

15. The method of claim 4, wherein the element selected from the group consisting of tin, silicon, and zinc is silicon.

16. The method of claim 4, wherein the element selected from the group consisting of tin, silicon, and zinc is zinc.

5. A non-aqueous electrolyte secondary battery comprising;

a positive electrode,

a negative electrode capable of intercalating and de-intercalating lithium,

a non-aqueous electrolyte solution, and

either a separator or a solid electrolyte;

wherein;

the negative electrode comprises a plurality of composite particles;

each of said composite particles comprise a nuclear particle consisting essentially of lithium and an element selected from the group consisting of tin, silicon, and zinc;

at least a part of a surface of each of the nuclear particles is coated with either a solid solution or an inter-metallic compound;

said solid solution or intermetallic compound comprises said element selected from the group consisting of tin, silicon, and zinc and at least one additional element;

said additional is selected from the group consisting of group 2 elements, transition elements, group 12 elements, group 13 elements, and group 14 elements exclusive of carbon, and exclusive of said element selected from the group consisting of tin, silicon, and zinc, and

the lithium content of said central portion is 40-95 atomic percent of the theoretical lithium content limit of the central portion.

6. The non-aqueous electrolyte secondary battery of claim 5, wherein the element selected from the group consisting of tin, silicon, and zinc is tin.

7. The non-aqueous electrolyte secondary battery of claim 5, wherein the element selected from the group consisting of tin, silicon, and zinc is silicon.

8. The non-aqueous electrolyte secondary battery of claim 5, wherein the element selected from the group consisting of tin, silicon, and zinc is zinc.

9. The non-aqueous electrolyte secondary battery of claim 5, wherein the additional element is selected from the group consisting of Mg, Fe, Mo, Zn, Cd, In, Pb, Co, Ni, Al, Sn, Cu, V, and Ge.

10. The non-aqueous electrolyte secondary battery of claim 5, wherein the lithium content of said central portion is 50-90 atomic percent of the theoretical lithium content limit of the central portion.

17. A method charging of a non-aqueous electrolyte secondary battery, said method comprising the steps of:

providing said battery, said battery comprising a positive electrode and a negative electrode;

wherein

the negative electrode comprises a plurality of composite particles

each of said composite particle comprises a central portion consisting essentially of lithium and at least one element selected from the group consisting of tin, silicon and zinc; and

a coating at least partially around said central portion,

said coating comprising a solid solution or an inter-metallic compound,

said solid solution or inter-metallic compound a) said at least one element selected from the group consisting of tin, silicon and zinc, and b) at least one element selected from the group consisting of group 2 elements, transition elements, group 12 elements, group 13 elements and group 14 elements exclusive of carbon, and exclusive of said at least element selected from the group consisting of tin, silicon, and zinc;

charging said battery at a constant current until reaching a predetermined voltage, and

charging said battery at said predetermined voltage after reaching said predetermined voltage said predetermined voltage producing a current;

wherein said constant current and said current produced by said predetermined voltage are at not more than 5 mA/cm2 current density at an area where said positive electrode and said negative electrodes face each other.

18. The method of claim 17, wherein the element selected from the group consisting of tin, silicon, and zinc is tin.

19. The method of claim 17, wherein the element selected from the group consisting of tin, silicon, and zinc is silicon.

20. The method of claim 17, wherein the element selected from the group consisting of tin, silicon, and zinc is zinc.