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EP-4742415-A1 - RECHARGEABLE BATTERY AND BATTERY PACK INCLUDING THE RECHARGEABLE BATTERY

EP4742415A1EP 4742415 A1EP4742415 A1EP 4742415A1EP-4742415-A1

Abstract

A rechargeable battery includes a case having a sidewall portion including a base layer. An electrode assembly is accommodated in the case. The sidewall portion includes a nanofiber web made of cellulose-based nanofibers and a polyolefin-based resin that are provided on one or both of an outer peripheral surface of the base layer and an inner peripheral surface of the base layer.

Inventors

  • SON, Il Oh

Assignees

  • Samsung SDI Co., Ltd.

Dates

Publication Date
20260513
Application Date
20251106

Claims (15)

  1. A rechargeable battery (2) comprising: a case (100) having a sidewall portion (110) including a base layer (110a); and an electrode assembly (200) accommodated in the case (100), wherein the sidewall portion (110) includes a nanofiber web including cellulose-based nanofibers (111) and a polyolefin-based resin (112) that are provided on one or both of an outer peripheral surface (A) of the base layer (110a) and an inner peripheral surface (B) of the base layer (110a).
  2. The rechargeable battery (2) of claim 1, wherein the polyolefin-based resin (112) is at least one of selected from the group consisting of polyethylene, polypropylene and copolymers thereof.
  3. The rechargeable battery (2) of claim 1 or 2, wherein the nanofiber web is embedded in the polyolefin-based resin (112).
  4. The rechargeable battery (2) of any one of the preceding claims, wherein the cellulose-based nanofibers (111) are crystalline cellulose-based nanofibers (111).
  5. The rechargeable battery (2) of any one of the preceding claims, wherein the cellulose-based nanofibers (111) include hydroxyl groups.
  6. The rechargeable battery (2) of claim 5, wherein the cellulose-based nanofibers include a cellulose-based resin or a derivative of a cellulose-based resin.
  7. The rechargeable battery (2) of claim 5, wherein some of the hydroxyl groups of the cellulose-based nanofibers (111) are modified to be hydrophobic.
  8. The rechargeable battery (2) of claim 7, wherein the cellulose-based nanofibers (111) modified to be hydrophobic are modified using a silane compound.
  9. The rechargeable battery (2) of claim 8, wherein the silane compound includes one or more of a silane coupling agent including an epoxy group, a silane coupling agent including an amino group, a silane coupling agent including a vinyl group, a silane coupling agent including a mercapto group, and a silane coupling agent including an alkyl group.
  10. The rechargeable battery (2) of any one of the preceding claims, wherein, the cellulose-based nanofibers (111) and the polyolefin-based resin (112) are in a mixture, and wherein the cellulose-based nanofibers (111) are 70 to 90 wt% of the mixture, and the polyolefin-based resin (112) are 10 to 30 wt% of the mixture.
  11. The rechargeable battery (2) of any one of the preceding claims, wherein the sidewall portion (110) includes an outer layer (110b) provided on the outer peripheral surface of the base layer (110a), wherein the outer layer (110b) surrounds the outer peripheral surface of the base layer (110a) and extends from an open portion (130a) of the case (100) to a bottom portion (120a) of the case (100), wherein the outer layer (110b) includes the polyolefin-based resin (112), and the nanofiber web made of the cellulose-based nanofibers (111) being embedded in the polyolefin-based resin (112), and wherein the nanofiber web extends from the open portion (130a) of the case (100) to the bottom portion (120a) of the case (100); and/or wherein the sidewall portion (110) includes an inner layer (110c) located on the inner peripheral surface of the base layer (110a), wherein the inner layer (110c) covers (12) the inner peripheral surface of the base layer (110a) and extends from an open portion (130a) of the case (100) to a bottom portion (120a) of the case (100); wherein the inner layer (110c) includes the polyolefin-based resin (112) and the nanofiber web made of the cellulose-based nanofibers (111) impregnated in the polyolefin-based resin (112), and wherein the nanofiber web extends from the open portion (130a) of the case (100) to the bottom portion (120a) of the case (100).
  12. The rechargeable battery (2) of claim 11, wherein the inner layer (110c) and/or the outer layer (110b) includes a region that only includes the polyolefin-based resin (112) and not the cellulose-based nanofibers (111).
  13. The rechargeable battery (2) of claim 11, wherein a ceramic-containing coating layer (110d) is provided between the base layer (110a) and the inner layer (110c).
  14. The rechargeable battery (2) of any one of the preceding claims, wherein the base layer (110a) includes at least one of steel, stainless steel, aluminum, and an aluminum alloy.
  15. A battery pack comprising: a housing (1); and a plurality of rechargeable batteries disposed inside the housing (1), wherein the rechargeable batteries each include a case (100) having a sidewall portion (110) including a base layer (110a) and an electrode assembly (200) accommodated in the case (100), wherein the sidewall portion (110) includes a nanofiber web including cellulose-based nanofibers (111) and a polyolefin-based resin (112) that are provided on one or both of an outer peripheral surface of the base layer (110a) and an inner peripheral surface of the base layer (110a).

Description

Field of the Disclosure The present disclosure relates to a rechargeable battery and a battery pack including the rechargeable battery. Discussion of Related Art With the rapid spread of electronic devices, such as mobile phones, laptop computers, and electric vehicles, the demand for rechargeable batteries with high energy density and high capacity has rapidly increased. Accordingly, research and development for improving performance of rechargeable lithium batteries are actively underway. A rechargeable lithium battery includes a positive electrode and a negative electrode including active materials that allow for intercalation and deintercalation of lithium ions and an electrolyte. The rechargeable lithium battery produces electrical energy through an oxidation-reduction reaction taking place when the lithium ions are intercalated and deintercalated to and from the positive electrode and the negative electrode. The information disclosed in section serves as the background of the present disclosure and may include information that does not constitute prior or related art. SUMMARY OF THE DISCLOSURE The invention is defined by the appended claims. The description that follows is subjected to this limitation. Any disclosure lying outside the scope of said claims is only intended for illustrative as well as comparative purposes. The present disclosure is directed to providing a rechargeable battery and a battery pack including the rechargeable battery. The rechargeable battery has high stability in the event of an external collision and is capable of suppressing ignition inside the battery. The rechargeable battery also has excellent moisture and oxygen blocking effects and is capable of suppressing expansion of the battery. The rechargeable battery also has excellent electrolyte impregnability. A rechargeable battery according to the present disclosure includes a case having a sidewall portion including a base layer; and an electrode assembly accommodated in the case, wherein the sidewall portion includes a nanofiber web including cellulose-based nanofibers and a polyolefin-based resin that are provided (directly) on one or both of an outer peripheral surface of the base layer and an inner peripheral surface of the base layer. A battery pack according to the present disclosure includes a housing; and a plurality of rechargeable batteries disposed inside the housing, wherein the rechargeable batteries each include a case having a sidewall portion including a base layer; and an electrode assembly accommodated in the case, wherein the sidewall portion includes a nanofiber web including of cellulose-based nanofibers and a polyolefin-based resin that are provided (directly) on one or both of an outer peripheral surface of the base layer and an inner peripheral surface of the base layer. According to the present disclosure, because a rechargeable battery includes a case including cellulose-based nanofibers and a polyolefin-based resin, stability of the battery in the event of an external collision is high, ignition inside the battery can be suppressed, a moisture and oxygen blocking effect is excellent, expansion of the battery can be suppressed, and electrolyte impregnability is excellent. BRIEF DESCRIPTION OF THE DRAWINGS The drawings illustrate preferred embodiments of the present disclosure by example. The disclosure is not limited to the embodiments set forth in the drawings. FIG. 1 is a perspective view of a battery pack according to various embodiments of the present disclosure.FIG. 2 is a perspective view of a rechargeable battery according to an embodiment of the present disclosure.FIG. 3 is a cross-sectional view of a rechargeable battery according to an embodiment of the present disclosure.FIG. 4 is a cross-sectional view in a thickness direction of a sidewall portion of a case of a rechargeable battery according to an embodiment of the present disclosure.FIG. 5 is a top view of an inner top configuration of the case of a rechargeable battery according to an embodiment of the present disclosure.FIG. 6 is a cross-sectional view of a configuration in a width direction of the case of a rechargeable battery according to an embodiment of the present disclosure.FIG. 7 is a cross-sectional view of a cross-sectional configuration in a thickness direction of a sidewall portion of the case of a rechargeable battery according to another embodiment of the present disclosure.FIG. 8 is a cross-sectional view of a cross-sectional configuration in a thickness direction of a sidewall portion of the case of a rechargeable battery according to yet another embodiment of the present disclosure.FIG. 9 is a cross-sectional view of a cross-sectional configuration in a thickness direction of a sidewall portion of the case of a rechargeable battery according to still another embodiment of the present disclosure. DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present disclosure will be described in detail with ref