Liquid absorbing sheet and nonaqueous electrolyte battery pack

• US 20060172199A1
• Filed: 04/01/2004
• Published: 08/03/2006
• Est. Priority Date: 05/30/2003
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Chemicals Corp. (Dexerials Corporation)
• Inventors: Hatsuda, Kouki, Fujita, Yasuhiro, Nomura, Mamiko, Moriyama, Hironobu
• Granted Patent: US 7,510,767 B2
• Time in Patent Office: Days
• US Class Current: 429/249
• CPC Class Codes: C08F 290/06 Polymers provided for in subclass C08G
• CPC Class Codes: C08F 290/061 Polyesters; Polycarbonates
• CPC Class Codes: C08F 290/065 Polyamides; Polyesteramides; Polyimides
• CPC Class Codes: Y10T 428/31504 Composite [nonstructural laminate]

Abstract

A liquid absorbing sheet has a liquid-absorbing resin layer that can effectively absorb the nonaqueous electrolyte solution used in nonaqueous electrolyte secondary cells that make nonaqueous electrolyte battery packs (in particular, lithium ion-based nonaqueous secondary battery packs). The liquid-absorbing resin layer is obtained by irradiating a particular monomer composition with UV rays or other energy rays to polymerize the monomer composition. The monomer composition contains a monofunctional monomer component (A) having a polyethylene glycol acrylate monomer and an amide bond-containing acrylic monomer; and a polyfunctional monomer component (B).

Claims

1. A liquid absorbing sheet comprising a liquid-absorbing resin layer, wherein the liquid-absorbing resin layer is obtained by irradiating a monomer composition with an energy ray to polymerize the monomer composition, the monomer composition containing a monofunctional monomer component (A) comprising a polyethylene glycol acrylate monomer and an amide bond-containing acrylic monomer;

and a polyfunctional monomer component (B).

2. The liquid absorbing sheet according to claim 1, wherein the polyethylene glycol acrylate monomer is phenoxypolyethylene glycol acrylate or methoxypolyethylene glycol acrylate.

3. The liquid absorbing sheet according to claim 1, wherein the amide bond-containing acrylic monomer is acryloylmorpholine or N,N-diethylacrylamide.

4. The liquid absorbing sheet according to claim 1, wherein the liquid-absorbing resin layer is formed over a substrate.

5. The liquid absorbing sheet according to claim 4, wherein the substrate is capable of absorbing and retaining a nonaqueous electrolyte solution.

6. A nonaqueous electrolyte battery pack comprising a nonaqueous electrolyte battery cell, a circuit board, an electrolyte-absorbing element for absorbing an electrolyte solution in the event of electrolyte leakage from the nonaqueous electrolyte battery cell, and a battery case encasing the battery cell, the circuit board and the electrolyte-absorbing element, wherein the electrolyte-absorbing element is formed of the liquid absorbing sheet according to claim 1.

7. The liquid absorbing sheet according to claim 2, wherein the liquid-absorbing resin layer is formed over a substrate.

8. The liquid absorbing sheet according to claim 3, wherein the liquid-absorbing resin layer is formed over a substrate.

9. A nonaqueous electrolyte battery pack comprising a nonaqueous electrolyte battery cell, a circuit board, an electrolyte-absorbing element for absorbing an electrolyte solution in the event of electrolyte leakage from the nonaqueous electrolyte battery cell, and a battery case encasing the battery cell, the circuit board and the electrolyte-absorbing element, wherein the electrolyte-absorbing element is formed of the liquid absorbing sheet according to claim 2.

10. A nonaqueous electrolyte battery pack comprising a nonaqueous electrolyte battery cell, a circuit board, an electrolyte-absorbing element for absorbing an electrolyte solution in the event of electrolyte leakage from the nonaqueous electrolyte battery cell, and a battery case encasing the battery cell, the circuit board and the electrolyte-absorbing element, wherein the electrolyte-absorbing element is formed of the liquid absorbing sheet according to claim 3.

11. A nonaqueous electrolyte battery pack comprising a nonaqueous electrolyte battery cell, a circuit board, an electrolyte-absorbing element for absorbing an electrolyte solution in the event of electrolyte leakage from the nonaqueous electrolyte battery cell, and a battery case encasing the battery cell, the circuit board and the electrolyte-absorbing element, wherein the electrolyte-absorbing element is formed of the liquid absorbing sheet according to claim 4.

12. A nonaqueous electrolyte battery pack comprising a nonaqueous electrolyte battery cell, a circuit board, an electrolyte-absorbing element for absorbing an electrolyte solution in the event of electrolyte leakage from the nonaqueous electrolyte battery cell, and a battery case encasing the battery cell, the circuit board and the electrolyte-absorbing element, wherein the electrolyte-absorbing element is formed of the liquid absorbing sheet according to claim 5.