Raw material of negative electrode material for nonaqueous secondary batteries, negative electrode material for nonaqueous secondary batteries, negative electrode for nonaqueous secondary batteries, and nonaqueous secondary battery

Patent metadata

Field	Value
Publication number	US-2022013779-A1
Application number	US-202117449125-A
Country	US
Kind code	A1
Filing date	Sep 28, 2021
Priority date	Mar 28, 2019
Publication date	Jan 13, 2022
Grant date	—

Abstract

A negative electrode material for a nonaqueous secondary battery which contains a graphite that contains an amorphous carbonaceous material in at least a part of the surface; has a cumulative pore volume of 0.100 mL/g or less in a pore size range of 0.01 μm to 1 μm; and satisfies at least one of the following conditions (1) and (2) in a DTA curve obtained by differential thermal analysis (DTA) in an air stream: (1) the negative electrode material has no exothermic peak in a temperature range of 550° C. to 650° C.; and (2) the negative electrode material has an exothermic peak in a temperature range of 550° C. to 650° C., and the area of the exothermic peak is larger than 0 μV·s/mg but 90 μV·s/mg or smaller; a negative electrode for a nonaqueous secondary battery, which contains the same; and a nonaqueous secondary battery are provided.

First claim

What is claimed is:

1 . A negative electrode material for a nonaqueous secondary battery, comprising a graphite that contains an amorphous carbonaceous material in at least a part of the surface thereof, having a cumulative pore volume of 0.100 mL/g or less in a pore size range of 0.01 μm or more and 1 μm or less, and satisfying at least one of the following conditions (1) and (2) in a DTA curve obtained by differential thermal analysis (DTA) in an air stream:
(1) the negative electrode material has no exothermic peak in a temperature range of 550° C. or higher and 650° C. or lower; and
(2) the negative electrode material has an exothermic peak in a temperature range of 550° C. or higher and 650° C. or lower, and the area of the exothermic peak is larger than 0 μV·s/mg but 90 μV·s/mg or smaller.

2 . The negative electrode material for a nonaqueous secondary battery according to claim 1 , satisfying the following condition (3) in the DTA curve:
(3) the negative electrode material has a heat generation start temperature in a temperature range of 550° C. or higher and 750° C. or lower.

3 . The negative electrode material for a nonaqueous secondary battery according to claim 1 , satisfying the following condition (4) in the DTA curve:
(4) the negative electrode material has an exothermic peak in a temperature range of higher than 650° C. but 1,000° C. or lower.

4 . The negative electrode material for a nonaqueous secondary battery according to claim 1 , having: a Raman R 2 value, which is calculated by the following Formula β, of 0.03 or more and 0.60 or less; and a Raman R 3 value, which is calculated by the following Formula γ, of 0.10 or more and 1.00 or less:
[Raman R 2 value]=[Intensity I C of valley (minimal value) between peak P A near 1,580 cm −1 and peak P B near 1,360 cm −1 ]/[Intensity I A of peak P A near 1,580 cm −1 ] in Raman spectrum analysis,  Formula β:

[Raman R 3 value]=[Intensity I C of valley (minimal value) between peak P A near 1,580 cm −1 and peak P B near 1,360 cm −1 ]/[Intensity I B of peak P B near 1,360 cm −1 ] in Raman spectrum analysis.  Formula γ:

5 . The negative electrode material for a nonaqueous secondary battery according to claim 1 , having a BET specific surface area (SA) of 0.5 m 2 /g or more and 10.0 m 2 /g or less.

6 . The negative electrode material for a nonaqueous secondary battery according to claim 1 , having a tap density of 0.60 g/cm 3 or more and 1.40 g/cm 3 or less.

7 . The negative electrode material for a nonaqueous secondary battery according to claim 1 , having an interplanar spacing (d002) of 0.340 nm or smaller and a crystallite size in the c-axis direction (Lc) of 90 nm or larger, as determined by X-ray diffractometry.

8 . A negative electrode for a nonaqueous secondary battery, comprising:
a current collector; and an active material layer formed on the current collector, wherein the active material layer comprises the negative electrode material according to claim 1 .

9 . A nonaqueous secondary battery, comprising:
a positive electrode; a negative electrode; and an electrolyte, wherein the negative electrode is the negative electrode for a nonaqueous secondary battery according to claim 8 .

10 . A negative electrode material for a nonaqueous secondary battery, having: a Raman R 1 value, which is calculated by the following Formula α, of 0.15 or more and 1.00 or less; a Raman full width at half maximum (Δν R ) of 65 cm −1 or more and 400 cm −1 or less; and a cumulative pore volume of 0.100 mL/g or less in a pore size range of 0.01 μm or more and 1 μm or less, and satisfying at least one of the following conditions (1) and (2) in a DTA curve obtained by differential thermal analysis (DTA) in an air stream:
(1) the negative electrode material has no exothermic peak in a temperature range of 550° C. or higher and 650° C. or lower; and
(2) the negative electrode material has an exothermic peak in a temperature range of 550° C. or higher and 650° C. or lower, and the area of the exothermic peak is larger than 0 μV·s/mg but 90 μV·s/mg or smaller,
[Raman R 1 value]=[Intensity I B of peak P B near 1,360 cm −1 ]/[Intensity I A of peak P A near 1,580 cm −1 ] in Raman spectrum analysis.  Formula α:

11 . The negative electrode material for a nonaqueous secondary battery according to claim 10 , satisfying the following condition (3) in the DTA curve:
(3) the negative electrode material has a heat generation start temperature in a temperature range of 550° C. or higher and 750° C. or lower.

12 . The negative electrode material for a nonaqueous secondary battery according to claim 10 , satisfying the following condition (4) in the DTA curve:
(4) the negative electrode material has an exothermic peak in a temperature range of higher than 650° C. but 1,000° C. or lower.

13 . The negative electrode material for a nonaqueous secondary battery according to claim 10 , having: a Raman R 2 value, which is calculated by the following Formula β, of 0.03 or more and 0.60 or less; and a Raman R 3 value, which is calculated by the following Formula γ, of 0.10 or more and 1.00 or less:
[Raman R 2 value]=[Intensity I C of valley (minimal value) between peak P A near 1,580 cm −1 and peak P B near 1,360 cm −1 ]/[Intensity I A of peak P A near 1,580 cm −1 ] in Raman spectrum analysis,  Formula β:

[Raman R 3 value]=[Intensity I C of valley (minimal value) between peak P A near 1,580 cm −1 and peak P D near 1,360 cm −1 ]/[Intensity I B of peak P B near 1,360 cm −1 ] in Raman spectrum analysis.  Formula γ:

14 . The negative electrode material for a nonaqueous secondary battery according to claim 10 , having a BET specific surface area (SA) of 0.5 m 2 /g or more and 10.0 m 2 /g or less.

15 . The negative electrode material for a nonaqueous secondary battery according to claim 10 , having a tap density of 0.60 g/cm 3 or more and 1.40 g/cm 3 or less.

16 . The negative electrode material for a nonaqueous secondary battery according to claim 10 , having an interplanar spacing (d002) of 0.340 nm or smaller and a crystallite size in the c-axis direction (Lc) of 90 nm or larger, as determined by X-ray diffractometry.

17 . A negative electrode for a nonaqueous secondary battery, comprising:
a current collector; and an active material layer formed on the current collector, wherein the active material layer comprises the negative electrode material according to claim 10 .

18 . A nonaqueous secondary battery, comprising:
a positive electrode; a negative electrode; and an electrolyte, wherein the negative electrode is the negative electrode for a nonaqueous secondary battery according to claim 17 .

19 . A negative electrode raw material for a nonaqueous secondary battery, comprising a graphite and being configured such that, when a mercury intrusion volume and a mercury extrusion volume, which are determined by a mercury intrusion method, are defined as A and B, respectively, the value of the following Formula (1) is 45% or higher:
B/A× 100(%).  Formula (1):

20 . The negative electrode raw material for a nonaqueous secondary battery according to claim 19 , wherein the mercury intrusion volume A is 0.001 mL/g or more and 0.5 mL/g or less.

21 . The negative electrode raw material for a nonaqueous secondary battery according to claim 19 , wherein the mercury extrusio

Assignees

• Mitsubishi Chem Corp

Inventors

• Yamada Shunsuke
• Ishiwatari Nobuyuki
• Sato Tomohiro
• Yoshida Hiroaki
• Kato Akihiro
• Yokomizo Masakazu
• Ikeda Hiromitsu
• Sato Hiroki

Classifications

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M4/133

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• H01M4/13

  Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof · CPC title

• H01M4/366 Primary

  as layered products · CPC title