NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

• US 20140322600A1
• Filed: 11/15/2011
• Published: 10/30/2014
• Est. Priority Date: 11/15/2011
• Status: Active Grant

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Morita, Masahiro, Fukumoto, Yusuke
• Granted Patent: US 10,446,824 B2
• Time in Patent Office: Days
• US Class Current: 429/212
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/4235 Safety or regulating additives or arrangements in electrodes, separators or electrolyte H01M10/4242 takes precedence
• CPC Class Codes: H01M 2200/10 Temperature sensitive devices
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 4/13 Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/622 being polymers
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/491 Porosity
• CPC Class Codes: H01M 50/581 in response to temperature
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A nonaqueous electrolyte secondary battery in accordance with the present invention is provided with an electrode body 20 including a positive electrode 30 and a negative electrode 50, and a nonaqueous electrode. The electrode body 20 is constituted by a plurality of different constituent members. At least two constituent members among the plurality of constituent members constituting the electrode body 20 include respective particulate polymers 38, 28 having a melting point within a temperature range from 80° C. to 120° C., with these two members being different from each other. The electrode body 20 is provided with the positive electrode 30 including a positive electrode active material layer 34 on a positive electrode collector 32, the negative electrode 50 including a negative electrode active material layer 54 on a negative electrode collector 52, separators 70A, 70B interposed between the positive electrode 30 and the negative electrode 50, and nonaqueous electrolyte. It is preferred that two or all of the positive electrode 30, the negative electrode 50, and the separators 70A, 70B include the particulate polymers 38, 78.

Claims

1. A nonaqueous electrolyte secondary battery, comprising:

an electrode body including a positive electrode and a negative electrode; and

a nonaqueous electrolyte;

wherein

the electrode body is constituted by a plurality of different constituent members; and

at least two constituent members from among the plurality of constituent members constituting the electrode body include respective particulate polymers having a melting point within a temperature range from 80°

C. to 120°

C., with these two members being different from each other.

2. The nonaqueous electrolyte secondary battery according to claim 1, wherein

the electrode body comprises the positive electrode including a positive electrode active material layer on a positive electrode collector, the negative electrode including a negative electrode active material layer on a negative electrode collector, and a separator interposed between the positive electrode and the negative electrode;

and

two or all of the positive electrode, the negative electrode, and the separator include the particulate polymers.

3. The nonaqueous electrolyte secondary battery according to claim 1, wherein

the positive electrode has, as constituent members, the positive electrode collector, the positive electrode active material layer, and a conductive intermediate layer including a conductive material and a binder between the positive electrode collector and the positive electrode active material layer;

the separator has, as constituent members, a separator main body and a heat resistance layer including an inorganic filler and a binder on at least one surface of the main body; and

the particulate polymer is included in at least the conductive intermediate layer and the heat resistance layer from among the constituent members.

4. The nonaqueous electrolyte secondary battery according to claim 3, wherein

the particulate polymer contained in the conductive intermediate layer and the particulate polymer contained in the heat resistance layer differ from each other, and the melting point of the particulate polymer contained in the conductive intermediate layer is lower than the melting point of the particulate polymer contained in the heat resistance layer.

5. The nonaqueous electrolyte secondary battery according to claim 3, wherein the ratio of the particulate polymer contained in the conductive intermediate layer is 10% by mass to 30% by mass when the total content ratio of the conductive intermediate layer is 100% by mass.

6. The nonaqueous electrolyte secondary battery according to claim 3, wherein the ratio of the particulate polymer contained in the heat resistance layer is 10% by mass to 40% by mass when the total content ratio of the heat resistance layer is 100% by mass.

7. The nonaqueous electrolyte secondary battery according to claim 3, wherein a D₅₀ particle diameter of the inorganic filler contained in the heat resistance layer is 0.5 μ

m to 5.0 μ

m, and a D₅₀ particle diameter of the particulate polymer is 0.1 μ

m to 3.0 μ

m.

8. The nonaqueous electrolyte secondary battery herein a porosity of the entire separator according to claim 2, wherein a porosity of the entire separator is 30% to 70%.

9. A vehicle provided with the nonaqueous electrolyte secondary battery according to claim 1.