LITHIUM ION SECONDARY BATTERY

• US 20150357679A1
• Filed: 02/28/2014
• Published: 12/10/2015
• Est. Priority Date: 03/01/2013
• Status: Active Grant

• Current Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Intellectual Property Management Co., Ltd. (Panasonic Holdings Corporation)
• Inventors: SANO, Yoko, YONEDA, Keisuke
• Granted Patent: US 9,666,903 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 10/0566 Liquid materials
• CPC Class Codes: H01M 10/0587 of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
• CPC Class Codes: H01M 2220/30 Batteries in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H01M 50/107 having curved cross-section, e.g. round or elliptic H01M50/103, H01M50/109, H01M50/11 take precedence
• CPC Class Codes: H01M 50/152 for cells having curved cross-section, e.g. round or elliptic H01M50/15, H01M50/153 take precedence
• CPC Class Codes: H01M 50/167 by crimping
• CPC Class Codes: H01M 50/171 using adhesives or sealing agents
• 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

Abstract

There is provided a cylindrical pin-type lithium-ion secondary battery having excellent high temperature storage characteristics and charge-discharge cycle characteristics. The battery includes: a bottom-closed cylindrical battery case having an opening portion; a wound-type electrode assembly and a non-aqueous electrolyte housed in the battery case; and a sealing plate sealing the opening portion. The battery has: an outer diameter R of 3 to 6.5 mm; a height H of 15 to 65 mm; an amount of the non-aqueous electrolyte per discharge capacity of 1 mAh of 1.7 to 2.8 μL; and a packing ratio of 71 to 85%.

Claims

1. A lithium-ion secondary battery having a cylindrical shape and comprising:

a bottom-closed cylindrical battery case having an opening portion;

a wound-type electrode assembly and a non-aqueous electrolyte housed in the battery case; and

a sealing plate sealing the opening portion,

the wound-type electrode assembly including;

a positive electrode;

a negative electrode; and

a separator interposed between the positive electrode and the negative electrode, and

the lithium-ion secondary battery having;

an outer diameter R of 3 to 6.5 mm and a height H of 15 to 65 mm;

an amount of the non-aqueous electrolyte per discharge capacity of 1 mAh of 1.7 to 2.8 μ

L; and

a packing ratio of 71 to 85%.

2. The lithium-ion secondary battery according to claim 1, wherein the packing ratio is 71 to 83%.

3. The lithium-ion secondary battery according to claim 1, wherein an occupying ratio of the electrode assembly occupying an internal volume of the lithium-ion secondary battery is 43 to 54 vol %.

4. The lithium-ion secondary battery according to claim 1, wherein the amount of the non-aqueous electrolyte per discharge capacity of 1 mAh is 1.8 to 2.7 μ

L.

5. The lithium-ion secondary battery according to claim 1, wherein the amount of the non-aqueous electrolyte per discharge capacity of 1 mAh is 1.8 to 2.4 μ

L.

6. The lithium-ion secondary battery according to claim 1 having a capacity density per volume of 60 to 110 mAh/cm³.

7. The lithium-ion secondary battery according to claim 1, wherein the number of winding turns for the electrode assembly is 3 to 10.

8. The lithium-ion secondary battery according to claim 1,

wherein the opening portion of the battery case is sealed with the sealing plate by bending an opening edge portion of the battery case inward toward the sealing plate, with a gasket interposed between the opening portion and the sealing plate, and

an insulating layer formed of an electrical insulating material is disposed on at least an outer surface of the bent opening edge portion and a portion peripheral to the bent opening edge portion.

9. The lithium-ion secondary battery according to claim 1, wherein a ratio of a distance h between a bottom surface of the sealing plate and an upper end surface of the electrode assembly relative to the outer diameter R:

h/R, is 0.1 to 1.7.