US-20260128425-A1 - RECHARGEABLE BATTERY AND BATTERY PACK INCLUDING THE RECHARGEABLE BATTERY

US20260128425A1US 20260128425 A1US20260128425 A1US 20260128425A1US-20260128425-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

Il Oh SON

Assignees

SAMSUNG SDI CO., LTD.

Dates

Publication Date: 20260507
Application Date: 20251107
Priority Date: 20241107

Claims (20)

1 . A rechargeable battery comprising: 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 on one or both of an outer peripheral surface of the base layer and an inner peripheral surface of the base layer.
2 . The rechargeable battery of claim 1 , wherein the polyolefin-based resin is a polypropylene-based resin.
3 . The rechargeable battery of claim 1 , wherein the nanofiber web is impregnated in the polyolefin-based resin.
4 . The rechargeable battery of claim 1 , wherein the cellulose-based nanofibers are crystalline cellulose-based nanofibers.
5 . The rechargeable battery of claim 1 , wherein the cellulose-based nanofibers include hydroxyl groups.
6 . The rechargeable battery 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 of claim 5 , wherein some of the hydroxyl groups of the cellulose-based nanofibers are modified to be hydrophobic.
8 . The rechargeable battery of claim 7 , wherein the cellulose-based nanofibers modified to be hydrophobic are modified using a silane compound.
9 . The rechargeable battery 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 of claim 1 , wherein, the cellulose-based nanofibers and the polyolefin-based resin are in a mixture, and wherein the cellulose-based nanofibers are 70 to 90 wt % of the mixture, and the polyolefin-based resin are 10 to 30 wt % of the mixture.
11 . The rechargeable battery of claim 1 , wherein the sidewall portion includes an outer layer provided on the outer peripheral surface of the base layer, wherein the outer layer surrounds the outer peripheral surface of the base layer and extends from an open portion of the case to a bottom portion of the case, wherein the outer layer includes the polyolefin-based resin, and the nanofiber web made of the cellulose-based nanofibers is impregnated in the polyolefin-based resin, and wherein the nanofiber web extends from the open portion of the case to the bottom portion of the case.
12 . The rechargeable battery of claim 11 , wherein the outer layer include a region that only includes the polyolefin-based resin and not the cellulose-based nanofibers.
13 . The rechargeable battery of claim 11 , wherein a portion of the nanofiber web has porosity.
14 . The rechargeable battery of claim 1 , wherein the sidewall portion includes an inner layer located on the inner peripheral surface of the base layer, wherein the inner layer covers the inner peripheral surface of the base layer and extends from an open portion of the case to a bottom portion of the case; wherein the inner layer includes the polyolefin-based resin and the nanofiber web made of the cellulose-based nanofibers impregnated in the polyolefin-based resin, and wherein the nanofiber web extends from the open portion of the case to the bottom portion of the case.
15 . The rechargeable battery of claim 14 , wherein the inner layer includes a region that only includes the polyolefin-based resin and not the cellulose-based nanofibers.
16 . The rechargeable battery of claim 14 , wherein a portion of the nanofiber web has porosity.
17 . The rechargeable battery of claim 14 , wherein a ceramic-containing coating layer is provided between the base layer and the inner layer.
18 . The rechargeable battery of claim 14 , wherein the sidewall portion further includes an outer layer located on the outer peripheral surface of the base layer, wherein the outer layer covers the outer peripheral surface of the base layer and extends from an open portion of the case to a bottom portion of the case, wherein the outer layer includes the polyolefin-based resin and the nanofiber web made of the cellulose-based nanofibers impregnated in the polyolefin-based resin, and wherein the nanofiber web extends from the open portion of the case to the bottom portion of the case.
19 . The rechargeable battery of claim 1 , wherein the base layer includes at least one of steel, stainless steel, aluminum, and an aluminum alloy.
20 . A battery pack comprising: 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 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.

Description

CROSS-REFERENCE TO RELATED APPLICATION The present application claims priority and the benefit of Korean Patent Application No. 10-2024-0157282, filed on Nov. 7, 2024, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference. 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 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. However, objectives of the present disclosure are not limited to the above-mentioned objectives, and other unmentioned objectives will be clearly understood by those of ordinary skill in the art from the description below. 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 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 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. However, the effects obtainable through the present disclosure are not limited to the effects described above, and other technical effects not mentioned will be clearly understood by those skilled in the art from the description below. 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 confi