KR20010037835A - Lithium ion polymer battery - Google Patents

Lithium ion polymer battery Download PDF

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Publication number
KR20010037835A
KR20010037835A KR1019990045557A KR19990045557A KR20010037835A KR 20010037835 A KR20010037835 A KR 20010037835A KR 1019990045557 A KR1019990045557 A KR 1019990045557A KR 19990045557 A KR19990045557 A KR 19990045557A KR 20010037835 A KR20010037835 A KR 20010037835A
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South Korea
Prior art keywords
case
lithium ion
ion polymer
battery cell
battery
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KR1019990045557A
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Korean (ko)
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KR100573100B1 (en
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서현미
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김순택
삼성에스디아이 주식회사
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/058—Construction or manufacture
    • H01M10/0585—Construction or manufacture of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Abstract

PURPOSE: A lithium ion polymer battery is provided which improves its stability and reliability by decreasing its badness rate. CONSTITUTION: The lithium ion polymer battery comprises: (i) a battery cell(20) where a positive plate(21), a negative plate(23) and a separator(25) are layered; (ii) a case(10) which accommodates the battery cell and electrolytic solution; and (iii) an insulating layer(30) which is placed on the inner side of the case to prevent short of the case and each pole plate, where the insulating layer is prepared by coating the inner side of the case with one material selected from polyethylene, polypropylene or teflon.

Description

리튬 이온 폴리머전지{Lithium ion polymer battery}Lithium ion polymer battery

본 발명은 리튬 이온 폴리머전지에 관한 것으로, 상세하게는 대용량 전지셀을 구성하기 위해 적층된 극판과 케이스와의 쇼트 현상을 방지할 수 있도록 구조가 개선된 리튬 이온 폴리머전지에 관한 것이다.The present invention relates to a lithium ion polymer battery, and more particularly, to a lithium ion polymer battery having an improved structure to prevent a short phenomenon between a stacked electrode plate and a case for forming a large capacity battery cell.

비디오 카메라, 휴대용 전화, 휴대용 PC 등의 휴대용 무선 기기제품과 전기자전거, 전기자동차, 전동공구 등의 경량화 및 고기능화가 진행됨에 따라, 그 구동용 전원으로 사용되는 전지에 대해서 중요성이 증가되고 있고, 많은 연구가 이루어지고 있다.As portable wireless device products such as video cameras, portable telephones, and portable PCs, and lightweight and high functional electronic bicycles, electric vehicles, and electric tools are progressing, the importance of batteries used as driving power sources is increasing. Research is being done.

특히, 충, 방전이 가능한 리튬 2차전지는 기존의 납 축전지, 니켈-카드뮴 전지, 니켈-수소전지, 니켈-아연전지 등과 비교하여 단위 중량당 에너지 밀도가 3배정도 높고 급속 충전이 가능하기 때문에 연구 개발이 활발하게 진행되고 있다.In particular, the lithium secondary battery that can be charged and discharged has three times higher energy density per unit weight and rapid charging than conventional lead-acid batteries, nickel-cadmium batteries, nickel-hydrogen batteries, and nickel-zinc batteries. This is actively going on.

리튬 2차 전지는 전해질 종류에 따라 액체 전해질을 사용하는 리튬 금속전지와 리튬 이온전지, 그리고 고분자 고체 전해질을 사용하는 리튬 이온 폴리머전지로 구분할 수 있다.Lithium secondary batteries can be classified into lithium metal batteries using a liquid electrolyte, lithium ion batteries, and lithium ion polymer batteries using a polymer solid electrolyte, depending on the type of electrolyte.

상기 리튬 이온전지는 통상 박판형태의 양극판과 음극판 및 세퍼레이터들을 적층시키고. 이 적층구조물을 롤(roll)의 형태로 말아서 된 전지셀을 원통형 케이스에 내에 수용시켜 된 원통형 구조로서 소형이고 저용량이다. 반면에, 예를 들어 전기자동차용 전지로 채용될 수 있는 리튬 이온 폴리머전지는 큰 에너지를 제공할 수 있도록 면적이 큰 양극판과 음극판 및 세퍼레이터(Seperator)를 양극판-세퍼레이터-음극판-세퍼레이터 순으로 적층시킨 후 소정 절단기를 이용하여 절단하여 제작된 대용량의 전지셀과, 이 대용량의 전지셀이 삽입되는 케이스를 구비한다. 또한, 상기 대용량의 전지셀은 리튬 이온전지와는 달리 적층된 구조이므로 양극판과 음극판 모두가 상기 케이스쪽으로 노출되며, 케이스는 전지의 안전성을 고려하여 서스케이스가 사용된다.The lithium ion battery is a laminate of a positive electrode plate and a negative electrode plate and separator in the form of a thin plate. The laminated structure is a cylindrical structure in which a battery cell rolled in the form of a roll is accommodated in a cylindrical case, and is small in size and low in capacity. On the other hand, for example, a lithium ion polymer battery, which can be employed as a battery for an electric vehicle, is formed by stacking a large-area positive electrode plate, negative electrode plate, and separator in the order of positive plate-separator-negative plate-separator to provide large energy. And a large capacity battery cell produced by cutting using a predetermined cutter, and a case into which the large capacity battery cell is inserted. In addition, since the large capacity battery cell is stacked structure unlike lithium ion batteries, both the positive electrode plate and the negative electrode plate are exposed to the case, and a case is used in consideration of battery safety.

그런데, 상기와 같은 구성에 있어서, 상기 대용량 전지셀의 제작시 절단기에에 의해 절단된 각 극판의 절단부에는 버(burr)가 형성되어 세퍼레이터 사이로 노출된다. 따라서, 이러한 버는 상기 서스케이스 내에 함침된 유기전해액에 의해 상기 극판들이 부풀어 압력이 발생되고, 그 압력에 의해 전지셀 자체가 팽창될 때, 서스케이스 내측에 접촉될 수 있다. 이 경우 쇼트(short)가 발생되며 특히, 전기자동차용 전지의 경우 수십장의 극판이 서스케이스 내에 삽입되는데, 이 중에서 극판 한 장이라도 쇼트가 나면 대용량 전지는 전체적으로 쇼트가 나게 되어 불량이 발생하게 되는 문제점이 있다.By the way, in the above structure, a burr is formed in the cutout of each pole plate cut by the cutter at the time of manufacturing the large capacity battery cell, and is exposed between the separators. Therefore, such burrs may be in contact with the inside of the suspension when the electrode plates are inflated by the organic electrolyte solution impregnated in the case, and the battery cell itself is expanded by the pressure. In this case, a short is generated. In particular, in the case of an electric vehicle battery, dozens of pole plates are inserted into a susceptible case. Among these, when a single pole plate is shorted, a large capacity battery is shortened as a whole, causing a problem. There is this.

본 발명은 상기와 같은 문제점을 해결하기 위해 창안된 것으로, 극판과 케이스와의 쇼트를 방지하도록 구조가 개선된 리튬 이온 폴리머전지를 제공하는데 그 목적이 있다.The present invention was devised to solve the above problems, and an object thereof is to provide a lithium ion polymer battery having an improved structure to prevent a short between a pole plate and a case.

도 1은 본 발명의 실시예에 따른 리튬 이온 폴리머전지를 개략적으로 나타낸 단면도.1 is a cross-sectional view schematically showing a lithium ion polymer battery according to an embodiment of the present invention.

＜ 도면의 주요부분에 대한 부호의 설명 ＞<Explanation of symbols for the main parts of the drawings>

10..케이스 11..양극단자10.Case 11.Anode terminal

13..음극단자 20..전지셀13..Negative electrode terminal 20..Battery cell

21..양극판 23..음극판21..Anode plate 23..Anode plate

25..세퍼레이터 30..절연층25. Separator 30. Insulation layer

상기 목적을 달성하기 위한 본 발명에 따른 리튬 이온 폴리머전지는, 양극판과 음극판 및 세퍼레이터가 적층되어 있는 구조의 전지셀과; 상기 전지셀과 전해질액이 수용되는 케이스; 및 상기 케이스와 상기 각 극판의 쇼트를 방지하도록 상기 케이스 내측면에 마련된 절연층;을 포함하는 것을 특징으로 한다.According to an aspect of the present invention, there is provided a lithium ion polymer battery comprising: a battery cell having a structure in which a positive electrode plate, a negative electrode plate, and a separator are stacked; A case accommodating the battery cell and the electrolyte solution; And an insulating layer provided on the inner surface of the case so as to prevent a short between the case and each of the electrode plates.

이하 첨부된 도면을 참조하여 본 발명의 실시예에 따른 리튬 이온 폴리머전지를 자세히 설명하기로 한다.Hereinafter, a lithium ion polymer battery according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.

도 1은 본 발명의 실시예에 따른 리튬 이온 폴리머전지를 나타낸 개략적인 단면도이다. 도면을 참조하면, 본 발명의 실시예에 따른 리튬 이온 폴리머전지는 케이스(10)와. 이 케이스(10) 내에 설치된 전지셀(20)과, 케이스(10) 내측에 마련된 절연층(30)을 구비한다.1 is a schematic cross-sectional view showing a lithium ion polymer battery according to an embodiment of the present invention. Referring to the drawings, the lithium ion polymer battery according to an embodiment of the present invention and the case (10). The battery cell 20 provided in the case 10 and the insulating layer 30 provided inside the case 10 are provided.

상기 케이스(10)는 밀폐형 구조로서 전지의 안전을 고려하여 알루미늄(Al)으로 제작되며, 그 내부에는 상기 전지셀(20)과 함께 소정 전해질액이 수용된다. 또한 케이스(10)에는 도시된 바와 같이 외부로 양극단자(11)와 음극단자(13)가 각각 노출되도록 설치되어 있다. 또한, 도시되지는 않았으나 상기 양극단자(11)만이 설치되며, 케이스(10) 자체가 음극단자(13)의 기능을 하도록 전지셀(20)에 연결될 수도 있다.The case 10 has a hermetic structure and is made of aluminum (Al) in consideration of battery safety, and a predetermined electrolyte solution is accommodated together with the battery cell 20. In addition, the case 10 is provided to expose the positive electrode terminal 11 and the negative electrode terminal 13 to the outside, as shown. In addition, although not shown, only the positive terminal 11 may be installed, and the case 10 itself may be connected to the battery cell 20 to function as the negative terminal 13.

상기 전지셀(20)은 상기 양극단자(11)와 전기적으로 연결되는 박막형의 양극판(21)과, 음극단자(13)와 전기적으로 연결되는 박막형의 음극판(23) 및, 양극판(21)과 음극판(23) 사이에 개재되는 절연용 세퍼레이터(25)를 구비한다. 이러한 전지셀(20)은 복수의 상기 양극판(21)과 음극판(23) 및 세퍼레이터(25)가 음극판-세퍼레이터-양극판-세퍼레이터의 순으로 적층한 후 소정의 절단기(미도시)를 이용해 절단함으로써 제작된다. 또한, 도면에서 구체적으로 도시하지는 않았으나, 상기 각 양극판(21)과 음극판(23) 각각은 소정의 전극탭(tap)을 통해 상기 각 단자(11)(13)에 연결될 수 있다.The battery cell 20 is a thin film positive electrode plate 21 electrically connected to the positive electrode terminal 11, a thin film negative electrode plate 23 electrically connected to the negative electrode terminal 13, and a positive electrode plate 21 and a negative electrode plate. The insulating separator 25 interposed between 23 is provided. The battery cell 20 is manufactured by stacking a plurality of the positive electrode plates 21, the negative electrode plates 23, and the separators 25 in the order of a negative electrode plate-separator-anode plate-separator, and then cutting them using a predetermined cutter (not shown). do. In addition, although not specifically illustrated in the drawings, each of the positive electrode plates 21 and the negative electrode plates 23 may be connected to the terminals 11 and 13 through a predetermined electrode tab.

상기 절연층(30)은 케이스(10)의 내측과 전지셀(20) 사이를 절연시키기 위한 것으로, 케이스(10) 내측면에 마련된다. 이 절연층(30)은 폴리에틸렌(PE;Polyethylene), 폴리프로필렌(PP;Polypropylene) 또는 테플론(Teflon)과 같이 전해액에 반응하지 않고 절연성을 가지는 물질로 케이스(10) 내측면에 코팅형성되는 것이 바람직하다. 또한, 상기 절연층(30)은 상기한 절연물질로 구성된 박막형의 판구조로 제작되어 케이스(10) 내에 삽입될 수도 있다.The insulating layer 30 is to insulate between the inside of the case 10 and the battery cell 20, and is provided on the inner surface of the case 10. The insulating layer 30 may be formed on the inner surface of the case 10 by a material having an insulating property without reacting with an electrolyte such as polyethylene (PE; polyethylene), polypropylene (PP; polypropylene), or teflon (Teflon). Do. In addition, the insulating layer 30 may be manufactured in a thin plate-like plate structure made of the insulating material and inserted into the case 10.

상술한 바와 같이 구성된 본 발명에 따른 리튬 이온 폴리머전지는 케이스(10) 내에 함침된 전해질액에 의해 각 극판(21)(23)들이 부풀어져서 전지셀(20)이 팽창하더라도, 종래와는 달리 전지셀(20)의 제작시 절단부에 형성되는 버(burr, 미도시)가 극판들(21)(23)끼리의 눌림에 의해 케이스(10) 내측면에 직접 접촉되지 않게 된다. 따라서, 케이스(10)와 극판(21)(23)의 접촉으로 인한 쇼트를 방지할 수 있다.In the lithium ion polymer battery according to the present invention configured as described above, even if each of the electrode plates 21 and 23 are inflated by the electrolyte solution impregnated in the case 10, the battery cell 20 is expanded, unlike the conventional battery. The burrs (not shown) formed in the cut portion during the manufacture of the cell 20 are not directly in contact with the inner surface of the case 10 by the pressing of the pole plates 21 and 23. Therefore, the short due to the contact between the case 10 and the electrode plates 21 and 23 can be prevented.

이상에서 설명한 바와 같이, 본 발명에 따른 리튬 이온 폴리머전지는 케이스 내측에 절연층을 마련하는 간단한 구조에 의해 극판의 쇼트를 방지할 수 있다. 따라서, 전지의 불량률을 낮추어 제품의 안정성 및 신뢰성을 높일 수 있다.As described above, the lithium ion polymer battery according to the present invention can prevent short of the electrode plate by a simple structure in which an insulating layer is provided inside the case. Therefore, the failure rate of the battery can be lowered to increase the stability and reliability of the product.

특히, 본 발명에 따른 리튬 이온 폴리머전지는 대용량의 전류를 필요로 하는 전기자동차용으로 사용될 경우, 전기자동차의 안전성 및 신뢰성 향상에 대한 효과는 더욱 배가된다.In particular, when the lithium ion polymer battery according to the present invention is used for an electric vehicle requiring a large amount of current, the effect on the improvement of safety and reliability of the electric vehicle is further doubled.

Claims (2)

양극판과 음극판 및 세퍼레이터가 적층되어 있는 구조의 전지셀과;A battery cell having a structure in which a positive electrode plate, a negative electrode plate, and a separator are stacked; 상기 전지셀과 전해질액이 수용되는 케이스; 및A case accommodating the battery cell and the electrolyte solution; And 상기 케이스와 상기 각 극판의 쇼트를 방지하도록 상기 케이스 내측면에 마련된 절연층;을 포함하는 것을 특징으로 하는 리튬 이온 폴리머전지.And an insulating layer provided on an inner surface of the case to prevent shorting of the case and each of the electrode plates. 제1항에 있어서,The method of claim 1, 상기 절연층은 상기 케이스 내측면에 폴리에틸렌(PE;Polyethylene), 폴리프로필렌(PP;Polypropylene), 테플론(Teflon) 중에서 선택된 어느한 물질로 코팅된 것을 특징으로 하는 리튬 이온 폴리머전지.The insulating layer is a lithium ion polymer battery, characterized in that the inner surface of the case is coated with any material selected from polyethylene (PE; Polyethylene), polypropylene (PP; Polypropylene), Teflon (Teflon).
KR1019990045557A 1999-10-20 1999-10-20 Lithium ion polymer battery KR100573100B1 (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100686859B1 (en) * 2005-09-28 2007-02-26 삼성에스디아이 주식회사 Secondary battery
KR100720282B1 (en) * 2004-10-08 2007-05-22 주식회사 엘지화학 Secondary battery having an improved safety
KR100985596B1 (en) * 2008-07-01 2010-10-05 김용래 Inside-insulated aluminium case for electronic device, method for manufacturing the same, and electronic device cased with the aluminium case
KR102291119B1 (en) 2021-05-25 2021-08-23 배도철 Lithium polymer battery with excellent fire protection performance

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Publication number Priority date Publication date Assignee Title
JPH0541248A (en) * 1991-08-06 1993-02-19 Toshiba Battery Co Ltd Cylindrical lithium secondary battery
JPH05166537A (en) * 1991-12-16 1993-07-02 Matsushita Electric Ind Co Ltd Nonaqueous electrolyte secondary battery
KR19980073911A (en) * 1997-03-20 1998-11-05 홍건희 Lithium polymer secondary battery with short-circuit insulation layer

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100720282B1 (en) * 2004-10-08 2007-05-22 주식회사 엘지화학 Secondary battery having an improved safety
KR100686859B1 (en) * 2005-09-28 2007-02-26 삼성에스디아이 주식회사 Secondary battery
KR100985596B1 (en) * 2008-07-01 2010-10-05 김용래 Inside-insulated aluminium case for electronic device, method for manufacturing the same, and electronic device cased with the aluminium case
KR102291119B1 (en) 2021-05-25 2021-08-23 배도철 Lithium polymer battery with excellent fire protection performance
KR102361353B1 (en) 2021-05-25 2022-02-14 배도철 Lithium polymer battery with excellent fire protection performance

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