JP2017130301A - Nonaqueous electrolyte secondary battery and method of manufacturing nonaqueous electrolyte secondary battery - Google Patents

Nonaqueous electrolyte secondary battery and method of manufacturing nonaqueous electrolyte secondary battery Download PDF

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JP2017130301A
JP2017130301A JP2016007799A JP2016007799A JP2017130301A JP 2017130301 A JP2017130301 A JP 2017130301A JP 2016007799 A JP2016007799 A JP 2016007799A JP 2016007799 A JP2016007799 A JP 2016007799A JP 2017130301 A JP2017130301 A JP 2017130301A
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positive electrode
electrode
separator
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secondary battery
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遊馬 神山
Yuma Kamiyama
遊馬 神山
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Panasonic Corp
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    • 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

PROBLEM TO BE SOLVED: To highly suppress internal short-circuit which may occur due to the contact between a negative electrode and burr formed at an end portion of a positive electrode.SOLUTION: A nonaqueous electrolyte secondary battery 10 includes an electrode body 12 including plural positive electrodes 20, plural negative electrodes 25, and plural separator 30, the positive electrodes 20 and the negative electrode 25 are alternately laminated through each separator 30. Protrusions 31 of resin are formed on the surface of the separator 30 so as to surround the positive electrode 20 at positions where the protrusions overlap the negative electrode 25 outside the positive electrode 20.SELECTED DRAWING: Figure 2

Description

本開示は、非水電解質二次電池及び非水電解質二次電池の製造方法に関する。   The present disclosure relates to a non-aqueous electrolyte secondary battery and a method for manufacturing a non-aqueous electrolyte secondary battery.

正極、負極、及びセパレータをそれぞれ複数含み、正極及び負極がセパレータを介して交互に積層された積層型の電極体を備えるリチウムイオン電池が広く知られている（例えば、特許文献１参照）。リチウムイオン電池では、正負極間におけるリチウムイオンの円滑な移動を確保するため、負極が正極よりも大きく形成される。このため、負極の端部は正極の端から外側に張り出しており、例えば電池の充放電に伴って負極が膨張したときに正極側に曲がる場合がある。   A lithium ion battery including a plurality of positive electrodes, negative electrodes, and separators each including a stacked electrode body in which positive electrodes and negative electrodes are alternately stacked via separators is widely known (see, for example, Patent Document 1). In a lithium ion battery, the negative electrode is formed larger than the positive electrode in order to ensure smooth movement of lithium ions between the positive and negative electrodes. For this reason, the end of the negative electrode protrudes outward from the end of the positive electrode. For example, when the negative electrode expands due to charging / discharging of the battery, it may bend toward the positive electrode.

特許第５５５２３９８号公報Japanese Patent No. 5552398

ところで、正極は長尺状の正極集電体上に正極合材層を形成した後、所定の寸法に切断することで製造されるが、このとき、正極の端部にはバリと呼ばれる突起が形成される場合がある。正極と負極間にはセパレータが介在しているが、例えば負極端部が正極側に曲がって正極端部に押し付けられたときに、正極のバリがセパレータを貫通して負極と接触し、内部短絡が発生するおそれがある。本開示の目的は、かかる内部短絡の発生を十分に抑制することである。   By the way, the positive electrode is manufactured by forming a positive electrode mixture layer on a long positive electrode current collector and then cutting it into predetermined dimensions. At this time, protrusions called burrs are formed at the end of the positive electrode. May be formed. A separator is interposed between the positive electrode and the negative electrode. For example, when the negative electrode end is bent to the positive electrode side and pressed against the positive electrode end, the positive electrode burr penetrates the separator and contacts the negative electrode, causing an internal short circuit. May occur. An object of the present disclosure is to sufficiently suppress the occurrence of such an internal short circuit.

本開示に係る非水電解質二次電池は、正極、負極、及びセパレータをそれぞれ複数含み、正極及び負極がセパレータを介して交互に積層された電極体を備える非水電解質二次電池であって、負極及びセパレータは、正極よりも大きく、セパレータの表面には、正極よりも外側で負極と重なる位置に、正極を取り囲むように樹脂製の突起が形成されていることを特徴とする。   The nonaqueous electrolyte secondary battery according to the present disclosure is a nonaqueous electrolyte secondary battery including a plurality of positive electrodes, negative electrodes, and separators each including an electrode body in which positive electrodes and negative electrodes are alternately stacked via separators, The negative electrode and the separator are larger than the positive electrode, and a protrusion made of resin is formed on the surface of the separator so as to surround the positive electrode at a position overlapping the negative electrode outside the positive electrode.

本開示に係る非水電解質二次電池の製造方法は、正極を挟むように２枚のセパレータを重ね合わせた後、正極を取り囲むように当該各セパレータを樹脂糸で縫い合わせ、当該樹脂糸を加熱溶融させる工程を備え、セパレータの表面には、前記工程により、正極よりも外側で負極と重なる位置に、樹脂糸によって突起が形成されることを特徴とする。   In the method for manufacturing a non-aqueous electrolyte secondary battery according to the present disclosure, two separators are overlapped so as to sandwich the positive electrode, and then the separators are sewn with resin yarns so as to surround the positive electrode, and the resin yarns are heated and melted. And a protrusion is formed on the surface of the separator by a resin thread at a position overlapping the negative electrode outside the positive electrode.

本開示に係る非水電解質二次電池によれば、正極の端部に形成されるバリが負極と接触して発生し得る内部短絡を高度に抑制することができる。   According to the nonaqueous electrolyte secondary battery according to the present disclosure, it is possible to highly suppress an internal short circuit that may occur when a burr formed at the end of the positive electrode contacts the negative electrode.

実施形態の一例である非水電解質二次電池の外観を示す斜視図である。It is a perspective view which shows the external appearance of the nonaqueous electrolyte secondary battery which is an example of embodiment. 実施形態の一例である電極体の正面図である。It is a front view of the electrode body which is an example of embodiment. 図２中のＡＡ線断面図である。FIG. 3 is a sectional view taken along line AA in FIG. 2. 図２中のＢＢ線断面図である。FIG. 3 is a sectional view taken along line BB in FIG. 2. 実施形態の他の一例である電極体の正面図である。It is a front view of the electrode body which is another example of embodiment. 図５中のＣＣ線断面図である。It is CC sectional view taken on the line in FIG. 実施形態の他の一例である電極体の製造方法を説明するための図である。It is a figure for demonstrating the manufacturing method of the electrode body which is another example of embodiment.

上述のように、正極は長尺状の正極集電体を切断して製造されるため、正極の端部にはバリが形成される場合がある。従来の非水電解質二次電池では、例えば充放電に伴う負極の膨張により負極端部が正極側に曲がって正極端部に押し付けられることで、正極のバリがセパレータを貫通して負極と接触し、内部短絡が発生する可能性があった。本発明者らは、セパレータ表面の負極端部と重なる位置に、正極を取り囲むように樹脂製の突起を形成することで、かかる内部短絡が高度に抑制されることを見出したのである。本開示に係る非水電解質二次電池によれば、セパレータの表面に形成された突起によって負極の端部が支えられるため、負極の端部が正極側に曲がることが抑えられ、正極のバリが負極に刺さることが防止されるのである。   As described above, since the positive electrode is manufactured by cutting a long positive electrode current collector, burrs may be formed at the end of the positive electrode. In a conventional nonaqueous electrolyte secondary battery, for example, the negative electrode end bends to the positive electrode side and is pressed against the positive electrode end due to expansion of the negative electrode due to charge / discharge, so that the positive electrode burr penetrates the separator and contacts the negative electrode. There could be an internal short circuit. The present inventors have found that such an internal short circuit is highly suppressed by forming a resin protrusion so as to surround the positive electrode at a position overlapping the negative electrode end on the separator surface. According to the nonaqueous electrolyte secondary battery according to the present disclosure, since the end of the negative electrode is supported by the protrusion formed on the surface of the separator, the end of the negative electrode is prevented from bending to the positive electrode side, and the burr of the positive electrode is prevented. This prevents the negative electrode from being stuck.

セパレータの正極と対向する面に無機物層が形成される場合、セパレータは正極よりも外側に形成される複数の貫通孔を有し、正極を挟む２枚のセパレータが当該貫通孔に充填される接着剤によって互いに接合されることが好ましい。この場合、当該接着剤を用いて上記突起を形成することができる。即ち、各貫通孔に充填される接着剤はセパレータ表面にも設けられ、セパレータ表面に設けられた接着剤が各貫通孔の間に突起を形成する。   When the inorganic layer is formed on the surface of the separator that faces the positive electrode, the separator has a plurality of through holes formed outside the positive electrode, and two separators sandwiching the positive electrode are filled into the through holes. It is preferable that they are joined together by an agent. In this case, the protrusion can be formed using the adhesive. That is, the adhesive filled in each through hole is also provided on the separator surface, and the adhesive provided on the separator surface forms protrusions between the through holes.

以下、本開示の実施形態の一例について詳細に説明する。なお、本開示に係る非水電解質二次電池は以下で説明する実施形態に限定されない。実施形態の説明で参照する図面は模式的に記載されたものであるから、図面に描画された構成要素の寸法比率などは以下の説明を参酌して判断されるべきである。本明細書において「略〜」とは、略同一を例に説明すると、完全に同一はもとより、実質的に同一と認められるものを含む意図である。また、「端部」とは端及びその近傍を意味する。   Hereinafter, an example of an embodiment of the present disclosure will be described in detail. Note that the non-aqueous electrolyte secondary battery according to the present disclosure is not limited to the embodiments described below. Since the drawings referred to in the description of the embodiments are schematically described, the dimensional ratios of the components drawn in the drawings should be determined in consideration of the following description. In the present specification, “substantially to” is intended to include not only completely the same but also substantially recognized as the same when described by taking substantially the same as an example. Further, “end portion” means an end and its vicinity.

図１は、実施形態の一例である非水電解質二次電池１０の斜視図である。図１に例示するように、非水電解質二次電池１０は、外装体１１と、外装体１１内に収容された発電要素とを備える。非水電解質二次電池１０の好適な一例は、リチウムイオン電池である。発電要素は、電極体１２と、非水電解質とで構成される。非水電解質は、非水溶媒と、非水溶媒に溶解した電解質塩とを含む。非水電解質は、液体電解質に限定されず、固体電解質であってもよい。電解質塩は、リチウム塩であることが好ましい。   FIG. 1 is a perspective view of a nonaqueous electrolyte secondary battery 10 which is an example of an embodiment. As illustrated in FIG. 1, the nonaqueous electrolyte secondary battery 10 includes an exterior body 11 and a power generation element accommodated in the exterior body 11. A suitable example of the nonaqueous electrolyte secondary battery 10 is a lithium ion battery. The power generation element includes an electrode body 12 and a nonaqueous electrolyte. The non-aqueous electrolyte includes a non-aqueous solvent and an electrolyte salt dissolved in the non-aqueous solvent. The nonaqueous electrolyte is not limited to a liquid electrolyte, and may be a solid electrolyte. The electrolyte salt is preferably a lithium salt.

外装体１１は、例えば２枚のラミネートフィルムによって構成される。各ラミネートフィルムには、金属層の両面に樹脂層が形成されたフィルムを用いることが好適であり、互いに接触する樹脂層は熱圧着可能な樹脂で構成されていることが好ましい。金属層は、例えばアルミニウムの薄膜層であり、水分等の透過を防ぐ機能を有する。発電要素を収容する外装体は、ラミネートフィルムからなる外装体１１に限定されず、例えば金属製ケースであってもよい。   The exterior body 11 is composed of, for example, two laminated films. For each laminate film, it is preferable to use a film in which a resin layer is formed on both surfaces of a metal layer, and the resin layers in contact with each other are preferably made of a resin that can be thermocompression bonded. The metal layer is a thin film layer of aluminum, for example, and has a function of preventing permeation of moisture and the like. The exterior body that houses the power generation element is not limited to the exterior body 11 made of a laminate film, and may be a metal case, for example.

外装体１１は、上記発電要素を収容する収容部１３と、収容部１３の周囲に形成された封止部１４とを含む。外装体１１を構成する一方のラミネートフィルムがカップ形状に成形され、当該フィルムに扁平な略直方体形状の収容部１３が形成されている。収容部１３は、対向配置される他方のラミネートフィルムと反対側に凸となるように、一方のラミネートフィルムを絞り加工して形成される。封止部１４は、各ラミネートフィルムの端部同士を熱圧着して形成され、発電要素が収容される収容部１３の内部空間を密閉する。   The exterior body 11 includes a housing portion 13 that houses the power generation element, and a sealing portion 14 that is formed around the housing portion 13. One laminate film constituting the exterior body 11 is formed into a cup shape, and a flat, substantially rectangular parallelepiped housing portion 13 is formed on the film. The accommodating portion 13 is formed by drawing one laminate film so as to be convex on the opposite side to the other laminate film disposed opposite to the accommodation portion 13. The sealing part 14 is formed by thermocompression bonding ends of the respective laminate films, and seals the internal space of the accommodating part 13 in which the power generation element is accommodated.

非水電解質二次電池１０は、外装体１１から引き出された一対の電極端子（正極端子１５及び負極端子１６）を備える。正極端子１５及び負極端子１６は、外装体１１の長手方向一端から引き出されている。正極端子１５及び負極端子１６は、いずれも略平坦な板状体であって、封止部１４で各ラミネートフィルムに接合され、封止部１４を通って各フィルムの間から外装体１１の外部に引き出される。   The nonaqueous electrolyte secondary battery 10 includes a pair of electrode terminals (a positive electrode terminal 15 and a negative electrode terminal 16) drawn from the outer package 11. The positive electrode terminal 15 and the negative electrode terminal 16 are drawn from one end in the longitudinal direction of the exterior body 11. Each of the positive electrode terminal 15 and the negative electrode terminal 16 is a substantially flat plate-like body, and is bonded to each laminate film at the sealing portion 14, and passes through the sealing portion 14 and between each film to the outside of the exterior body 11. Pulled out.

図２〜図４は、実施形態の一例である電極体１２を示す図である（図２では、負極２５を仮想線で示す）。図２〜図４に例示するように、電極体１２は、正極２０、負極２５、及びセパレータ３０をそれぞれ複数含み、正極２０及び負極２５がセパレータ３０を介して交互に積層された構造を有する。電極の積層数は特に限定されないが、一般的には各々１０枚〜７０枚程度である。正負極間におけるリチウムイオンの円滑な移動を確保するため、負極２５は正極２０よりも大きく形成され、少なくとも正極２０の正極合材層が形成された部分は負極２５の負極合材層が形成された部分に対向配置される。   2-4 is a figure which shows the electrode body 12 which is an example of embodiment (in FIG. 2, the negative electrode 25 is shown with a virtual line). As illustrated in FIGS. 2 to 4, the electrode body 12 includes a plurality of positive electrodes 20, negative electrodes 25, and separators 30, and has a structure in which the positive electrodes 20 and the negative electrodes 25 are alternately stacked via the separators 30. The number of stacked electrodes is not particularly limited, but is generally about 10 to 70 each. In order to ensure smooth movement of lithium ions between the positive and negative electrodes, the negative electrode 25 is formed larger than the positive electrode 20, and at least a portion where the positive electrode mixture layer of the positive electrode 20 is formed is formed with the negative electrode mixture layer of the negative electrode 25. It is arranged opposite to the part.

電極体１２は、各正極２０に接続された複数の正極リード２１と、各負極２５に接続された複数の負極リード２６とを有する。本実施形態では、正極２０を構成する正極集電体の一部を突出させることで正極リード２１が形成され、負極２５を構成する負極集電体の一部を突出させることで負極リード２６が形成されている。複数の正極リード２１は互いに重ね合わされて正極端子１５に溶接され、正極２０と正極端子１５を電気的に接続する。また、複数の負極リード２６は互いに重ね合わされて負極端子１６に溶接され、負極２５と負極端子１６を電気的に接続する。   The electrode body 12 includes a plurality of positive leads 21 connected to the positive electrodes 20 and a plurality of negative leads 26 connected to the negative electrodes 25. In the present embodiment, a positive electrode lead 21 is formed by protruding a part of the positive electrode current collector constituting the positive electrode 20, and a negative electrode lead 26 is formed by protruding a part of the negative electrode current collector constituting the negative electrode 25. Is formed. The plurality of positive electrode leads 21 are overlapped with each other and welded to the positive electrode terminal 15 to electrically connect the positive electrode 20 and the positive electrode terminal 15. The plurality of negative electrode leads 26 are overlapped with each other and welded to the negative electrode terminal 16 to electrically connect the negative electrode 25 and the negative electrode terminal 16.

正極２０は、例えば正極集電体と、当該集電体上に形成された正極合材層とで構成される。正極集電体には、アルミニウムなどの正極の電位範囲で安定な金属の箔、当該金属を表層に配置したフィルム等を用いることができる。正極合材層は、正極活物質の他に、導電材及び結着材を含み、集電体の両面に形成されることが好ましい。正極活物質には、例えばリチウム含有複合酸化物が用いられる。好適な複合酸化物の一例としては、Ｎｉ−Ｃｏ−Ｍｎ系、Ｎｉ−Ｃｏ−Ａｌ系のリチウム含有複合酸化物が挙げられる。   The positive electrode 20 includes, for example, a positive electrode current collector and a positive electrode mixture layer formed on the current collector. As the positive electrode current collector, a metal foil that is stable in the potential range of the positive electrode such as aluminum, a film in which the metal is disposed on the surface layer, or the like can be used. The positive electrode mixture layer preferably includes a conductive material and a binder in addition to the positive electrode active material, and is formed on both surfaces of the current collector. As the positive electrode active material, for example, a lithium-containing composite oxide is used. As an example of a suitable composite oxide, a Ni-Co-Mn-based or Ni-Co-Al-based lithium-containing composite oxide can be given.

正極２０は、正面視略矩形形状を有する。正極合材層は、例えば正極２０の両面の略全域に形成される。正極合材層は、正極リード２１を構成する正極集電体の付け根に形成されてもよいが、正極リード２１の大部分には形成されない。これにより、正極リード２１の大部分で正極集電体の表面が露出し、正極リード２１と正極端子１５の良好な電気的接続が可能となる。正極リード２１は、正極２０の短辺方向一端側において長辺方向一端から突出し、正面視略矩形形状を有する。   The positive electrode 20 has a substantially rectangular shape when viewed from the front. The positive electrode mixture layer is formed, for example, over substantially the entire area of both surfaces of the positive electrode 20. The positive electrode mixture layer may be formed at the base of the positive electrode current collector constituting the positive electrode lead 21, but is not formed on most of the positive electrode lead 21. As a result, the surface of the positive electrode current collector is exposed at most of the positive electrode lead 21, and good electrical connection between the positive electrode lead 21 and the positive electrode terminal 15 becomes possible. The positive electrode lead 21 protrudes from one end in the long side direction at one end side in the short side direction of the positive electrode 20 and has a substantially rectangular shape in front view.

正極２０の厚みは、特に限定されないが、好ましくは６０μｍ〜８０μｍである。正極２０は、長尺状の正極集電体上に正極活物質、導電材、結着材等を含む正極合材スラリーを塗布し、塗膜を圧延して正極合材層を集電体の両面に形成した後、これを各々の正極２０及び正極リード２１の寸法に切断することにより製造できる。このとき、正極２０の端部には、上述のようにバリ２２が形成される場合がある。なお、正極合材スラリーは正極集電体上において正極リード２１となる部分には塗工されない。   The thickness of the positive electrode 20 is not particularly limited, but is preferably 60 μm to 80 μm. The positive electrode 20 is formed by applying a positive electrode mixture slurry containing a positive electrode active material, a conductive material, a binder, and the like onto a long positive electrode current collector, rolling the coating film, and forming a positive electrode mixture layer on the current collector After forming on both surfaces, it can manufacture by cut | disconnecting this to the dimension of each positive electrode 20 and the positive electrode lead 21. FIG. At this time, the burr 22 may be formed at the end of the positive electrode 20 as described above. The positive electrode mixture slurry is not applied to the portion that becomes the positive electrode lead 21 on the positive electrode current collector.

負極２５は、例えば負極集電体と、当該集電体上に形成された負極合材層とで構成される。負極集電体には、銅などの負極の電位範囲で安定な金属の箔、当該金属を表層に配置したフィルム等を用いることができる。負極合材層は、負極活物質の他に、結着材を含むことが好ましい。負極活物質としては、リチウムイオンを可逆的に吸蔵、放出できるものであれば特に限定されず、例えば天然黒鉛、人造黒鉛等の炭素材料、Ｓｉ、Ｓｎ等のリチウムと合金化する金属、合金、複合酸化物などを用いることができる。   The negative electrode 25 is composed of, for example, a negative electrode current collector and a negative electrode mixture layer formed on the current collector. As the negative electrode current collector, a metal foil that is stable in the potential range of a negative electrode such as copper, a film in which the metal is disposed on the surface layer, or the like can be used. The negative electrode mixture layer preferably contains a binder in addition to the negative electrode active material. The negative electrode active material is not particularly limited as long as it can reversibly occlude and release lithium ions. For example, carbon materials such as natural graphite and artificial graphite, metals such as Si and Sn, alloys that form an alloy with lithium, alloys, A composite oxide or the like can be used.

負極２５は、正極２０と同様に正面視略矩形形状を有するが、上述の通り負極２５の寸法は正極２０の寸法よりも大きい。負極合材層は、例えば負極２５の両面の略全域に形成される。負極合材層は、負極リード２６を構成する負極集電体の付け根に形成されてもよいが、負極リード２６の大部分には形成されず、負極リード２６の大部分で負極集電体の表面が露出している。負極リード２６は、セパレータ３０の短辺方向他端側、即ち正極リード２１と横方向反対側において長辺方向一端から突出し、正面視略矩形形状を有する。   The negative electrode 25 has a substantially rectangular shape in front view like the positive electrode 20, but the size of the negative electrode 25 is larger than the size of the positive electrode 20 as described above. The negative electrode mixture layer is formed, for example, on substantially the entire area of both surfaces of the negative electrode 25. The negative electrode mixture layer may be formed at the base of the negative electrode current collector constituting the negative electrode lead 26, but is not formed on most of the negative electrode lead 26, and most of the negative electrode lead 26 is formed of the negative electrode current collector. The surface is exposed. The negative electrode lead 26 protrudes from one end in the long side direction on the other end side in the short side direction of the separator 30, that is, on the side opposite to the positive electrode lead 21, and has a substantially rectangular shape in front view.

負極２５の厚みは、特に限定されないが、好ましくは６０μｍ〜８０μｍである。負極２５は、長尺状の負極集電体上に負極活物質、結着材等を含む負極合材スラリーを塗布し、塗膜を圧延して負極合材層を集電体の両面に形成した後、これを各々の負極２５及び負極リード２６の寸法に切断することにより製造できる。なお、負極合材スラリーは負極集電体上において負極リード２６となる部分には塗工されない。正極２０の場合と同様に、負極２５の端部にもバリが形成される場合がある。但し、バリが形成され得る負極２５の端部は、正極２０の端から外側に張り出しているため、これが原因で内部短絡が発生することは通常考えられない。   The thickness of the negative electrode 25 is not particularly limited, but is preferably 60 μm to 80 μm. The negative electrode 25 is formed by applying a negative electrode mixture slurry containing a negative electrode active material, a binder, etc. on a long negative electrode current collector, rolling the coating film, and forming negative electrode mixture layers on both sides of the current collector Then, it can be manufactured by cutting the negative electrode 25 and the negative electrode lead 26 into dimensions. Note that the negative electrode mixture slurry is not applied to the portion that becomes the negative electrode lead 26 on the negative electrode current collector. As in the case of the positive electrode 20, burrs may be formed at the end of the negative electrode 25. However, since the end portion of the negative electrode 25 where burr can be formed protrudes outward from the end of the positive electrode 20, it is not normally considered that an internal short circuit occurs due to this.

セパレータ３０は、正極２０と負極２５の間、及び正極リード２１と負極２５の間に介在している。即ち、電極体１２の厚み方向に正極２０及び正極リード２１と負極２５とが対向する部分には必ずセパレータ３０が設けられる。セパレータ３０は、正極２０、負極２５と同様に正面視略矩形形状を有し、正極２０よりも大きく形成される。本実施形態では、セパレータ３０が負極２５よりも大きく形成されている。但し、セパレータ３０は負極２５と同じ寸法であってもよく、負極２５より小さくすることも可能である。セパレータ３０の厚みは、特に限定されないが、好ましくは１０μｍ〜２５μｍ、より好ましくは１０μｍ〜１５μｍである。   The separator 30 is interposed between the positive electrode 20 and the negative electrode 25 and between the positive electrode lead 21 and the negative electrode 25. That is, the separator 30 is always provided in a portion where the positive electrode 20 and the positive electrode lead 21 and the negative electrode 25 face each other in the thickness direction of the electrode body 12. Like the positive electrode 20 and the negative electrode 25, the separator 30 has a substantially rectangular shape in front view and is formed larger than the positive electrode 20. In the present embodiment, the separator 30 is formed larger than the negative electrode 25. However, the separator 30 may have the same dimensions as the negative electrode 25 and may be smaller than the negative electrode 25. The thickness of the separator 30 is not particularly limited, but is preferably 10 μm to 25 μm, more preferably 10 μm to 15 μm.

セパレータ３０には、イオン透過性及び絶縁性を有する多孔性シートが用いられる。多孔性シートの具体例としては、微多孔薄膜、織布、不織布等が挙げられる。セパレータの材質としては、ポリエチレン、ポリプロピレン等のオレフィン系樹脂、セルロースなどが好ましい。セパレータは、セルロース繊維層及びオレフィン系樹脂等の熱可塑性樹脂繊維層を有する積層体であってもよく、ポリエチレン層及びポリプロピレン層を含む多層セパレータであってもよい。   For the separator 30, a porous sheet having ion permeability and insulating properties is used. Specific examples of the porous sheet include a microporous thin film, a woven fabric, and a nonwoven fabric. As the material of the separator, olefin resins such as polyethylene and polypropylene, cellulose and the like are preferable. The separator may be a laminate having a cellulose fiber layer and a thermoplastic resin fiber layer such as an olefin resin, or may be a multilayer separator including a polyethylene layer and a polypropylene layer.

正極２０又は負極２５を介して隣り合う２枚のセパレータ３０は、互いに接合されていてもよい。例えば、正極２０を挟む２枚のセパレータ３０が、正極２０よりも外側で正極２０を包み込むように接合されていてもよい。セパレータ３０の表面に後述する無機物層が形成されない場合、２枚のセパレータ３０の端部同士を重ね合わせて熱プレスすることで当該端部同士を溶着することができる。正極リード２１の先端側部分は、２枚のセパレータ３０の間から引き出されるが、各セパレータ３０は正極リード２１の表面に接合されていてもよい。   Two separators 30 adjacent to each other via the positive electrode 20 or the negative electrode 25 may be joined to each other. For example, two separators 30 sandwiching the positive electrode 20 may be joined so as to wrap the positive electrode 20 outside the positive electrode 20. When the inorganic substance layer mentioned later is not formed in the surface of the separator 30, the said edge parts can be welded by superposing | stacking the edge parts of the two separators 30, and carrying out the hot press. The tip side portion of the positive electrode lead 21 is drawn from between the two separators 30, but each separator 30 may be bonded to the surface of the positive electrode lead 21.

セパレータ３０の表面には、正極２０よりも外側で負極２５と重なる位置に、正極２０を取り囲むように樹脂製の突起３１が形成されている。突起３１は、セパレータ３０の表面に立設し、セパレータ３０の厚み方向に延びている。突起３１は、電極体１２の厚み方向に正極２０と重ならず且つ負極２５と重なる位置に形成される。つまり、正極２０の端から外側に張り出した負極２５の端部と対向する位置に突起３１が形成される。セパレータ３０の表面に形成された突起３１は、少なくとも負極２５が膨張したときに負極２５の端部に当接して当該端部が正極２０側に曲がることを抑制する。   On the surface of the separator 30, a resin protrusion 31 is formed so as to surround the positive electrode 20 at a position overlapping the negative electrode 25 outside the positive electrode 20. The protrusion 31 stands on the surface of the separator 30 and extends in the thickness direction of the separator 30. The protrusion 31 is formed at a position that does not overlap the positive electrode 20 and overlaps the negative electrode 25 in the thickness direction of the electrode body 12. That is, the protrusion 31 is formed at a position facing the end of the negative electrode 25 protruding outward from the end of the positive electrode 20. The protrusions 31 formed on the surface of the separator 30 abut against the end portion of the negative electrode 25 at least when the negative electrode 25 expands, and prevent the end portion from bending toward the positive electrode 20.

突起３１は、電極体１２の正面視において正極２０を取り囲むように形成されている。本実施形態では、セパレータ３０の表面のうち、電極体１２の厚み方向に正極２０と重ならない正極２０の周囲において、正極リード２１と重なる範囲以外に突起３１が形成されている。突起３１は正極リード２１と重なる範囲に形成されてもよいが、当該範囲に形成される突起３１は、他の部分に形成される突起３１よりも高さを低くすることが好ましい。突起３１は、セパレータ３０の両面に形成されてもよいが、好ましくは負極２５側に向いた面のみに形成される。即ち、正極２０を挟む２枚のセパレータ３０の突起３１は互いに反対方向に延びる。   The protrusion 31 is formed so as to surround the positive electrode 20 in a front view of the electrode body 12. In the present embodiment, a protrusion 31 is formed on the surface of the separator 30 around the positive electrode 20 that does not overlap the positive electrode 20 in the thickness direction of the electrode body 12 except for the range overlapping the positive electrode lead 21. The protrusion 31 may be formed in a range overlapping with the positive electrode lead 21, but the protrusion 31 formed in the range is preferably lower in height than the protrusion 31 formed in the other part. The protrusions 31 may be formed on both surfaces of the separator 30, but are preferably formed only on the surface facing the negative electrode 25 side. That is, the protrusions 31 of the two separators 30 sandwiching the positive electrode 20 extend in opposite directions.

突起３１は、正面視略矩形形状を有する正極２０の端に沿って、即ち正極２０の長辺及び短辺に沿って形成されている。正極リード２１と重なる範囲を除く正極２０の周囲には、複数の突起３１が略等間隔で一列に配置されている。複数の突起３１が並んで構成される突起３１の列は、正極２０の長辺又は短辺と略平行である。各突起３１は、この列に沿って長く延び、例えば長さ５ｍｍ〜１５ｍｍ、幅０．１ｍｍ〜１ｍｍで形成される。各突起３１の間隔は、１ｍｍ以下であることが好ましく、例えば０．１ｍｍ〜１ｍｍである。なお、突起３１は複数に分割されることなく、連続的に形成されてもよい。   The protrusion 31 is formed along the end of the positive electrode 20 having a substantially rectangular shape in front view, that is, along the long side and the short side of the positive electrode 20. A plurality of protrusions 31 are arranged in a line at substantially equal intervals around the positive electrode 20 except for a range overlapping the positive electrode lead 21. The row of the protrusions 31 formed by arranging the plurality of protrusions 31 is substantially parallel to the long side or the short side of the positive electrode 20. Each protrusion 31 extends long along this row, and is formed with a length of 5 mm to 15 mm and a width of 0.1 mm to 1 mm, for example. The interval between the protrusions 31 is preferably 1 mm or less, for example, 0.1 mm to 1 mm. The protrusion 31 may be formed continuously without being divided into a plurality of parts.

突起３１の高さｈ31は、例えば正極２０の厚みｔ20の半分（１／２）以下であり、好ましくは厚みｔ20の１／５〜１／２、より好ましくは厚みｔ20の１／３〜１／２であり、特に好ましくは厚みｔ20の略半分（略１／２）である。なお、高さｈ31とはセパレータ３０の表面から突起３１の先端までのセパレータ３０の厚み方向に沿った長さである。高さｈ31は、例えば５０μｍ〜１００μｍである。正極リード２１と重ならない範囲に形成される各突起３１の高さｈ31は、互いに略同一であることが好ましい。 The height h 31 of the protrusion 31 is, for example, not more than half (1/2) of the thickness t 20 of the positive electrode 20, preferably 1/5 to 1/2 of the thickness t 20 , more preferably 1 / th of the thickness t 20 . a 3-1 / 2, particularly preferably substantially half the thickness t 20 (about 1/2). The height h 31 is a length along the thickness direction of the separator 30 from the surface of the separator 30 to the tip of the protrusion 31. The height h 31 is, for example, 50 μm to 100 μm. It is preferable that the heights h 31 of the protrusions 31 formed in a range that does not overlap the positive electrode lead 21 are substantially the same.

突起３１を構成する樹脂は、セパレータ３０の表面に対する接着性が良好で、耐電解液性に優れる樹脂が好ましい。好適な樹脂としては、ポリエチレン、ポリプロピレン等のオレフィン系樹脂、ポリテトラフルオロエチレン（ＰＴＦＥ）、ポリフッ化ビニリデン（ＰＶｄＦ）等のフッ素系樹脂が挙げられる。突起３１は、例えばセパレータ３０の表面に、加熱溶融した樹脂、又は樹脂を溶剤に溶解した樹脂溶液を塗工することにより形成できる。或いは、細線状の樹脂をセパレータ３０の表面に配置し、これを熱プレスすることで形成できる。   The resin constituting the protrusion 31 is preferably a resin having good adhesion to the surface of the separator 30 and excellent resistance to electrolytic solution. Suitable resins include olefin resins such as polyethylene and polypropylene, and fluorine resins such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF). The protrusion 31 can be formed, for example, by applying a heat-melted resin or a resin solution in which a resin is dissolved in a solvent to the surface of the separator 30. Or it can form by arrange | positioning thin line-like resin on the surface of the separator 30, and hot-pressing this.

上記構成を備えた非水電解質二次電池１０によれば、セパレータ３０の表面に形成された突起３１によって正極２０の端から張り出した負極２５の端部を支持することができる。このため、負極２５の端部が正極２０側に曲がって正極２０の端部に押し付けられることがなく、正極２０の端部にバリ２２が存在する場合であっても、バリ２２と負極２５の接触により発生し得る内部短絡を防止することができる。   According to the nonaqueous electrolyte secondary battery 10 having the above configuration, the end of the negative electrode 25 protruding from the end of the positive electrode 20 can be supported by the protrusions 31 formed on the surface of the separator 30. Therefore, the end of the negative electrode 25 is not bent to the positive electrode 20 side and pressed against the end of the positive electrode 20, and even if the burr 22 exists at the end of the positive electrode 20, An internal short circuit that may occur due to contact can be prevented.

図５及び図６を参照しながら、実施形態の他の一例である電極体４２について詳説する。以下では、電極体１２との相違点を主に説明し、電極体１２と共通する構成要素には同じ符号を用いて重複する説明を省略する。   With reference to FIGS. 5 and 6, an electrode body 42 which is another example of the embodiment will be described in detail. Hereinafter, differences from the electrode body 12 will be mainly described, and the same reference numerals will be used for constituent elements common to the electrode body 12, and overlapping description will be omitted.

図５及び図６に例示するように、電極体４２は、セパレータ３０の代わりに、正極２０と対向する面に形成された無機物層５３を有するセパレータ５０を備える点で、電極体１２と異なる。セパレータ５０は、樹脂層５２と、樹脂層５２の表面のうち正極２０と対向する面に形成された無機物層５３とを有する。また、セパレータ５０は負極２５よりも外側に形成された複数の貫通孔５４を有する。貫通孔５４は、樹脂層５２及び無機物層５３を貫通して形成される。正極２０を挟む２枚のセパレータ５０は、それぞれの各貫通孔５４が電極体４２の厚み方向に重なるように積層され、各貫通孔５４に充填された接着剤５５により互いに接合されている。即ち、２枚のセパレータ５０が袋状に形成され、１枚の正極２０を包んでいる。   As illustrated in FIGS. 5 and 6, the electrode body 42 is different from the electrode body 12 in that the electrode body 42 includes a separator 50 having an inorganic layer 53 formed on the surface facing the positive electrode 20 instead of the separator 30. The separator 50 includes a resin layer 52 and an inorganic layer 53 formed on the surface of the resin layer 52 that faces the positive electrode 20. The separator 50 has a plurality of through holes 54 formed outside the negative electrode 25. The through hole 54 is formed through the resin layer 52 and the inorganic layer 53. The two separators 50 sandwiching the positive electrode 20 are laminated so that the respective through holes 54 overlap each other in the thickness direction of the electrode body 42, and are joined to each other by an adhesive 55 filled in each through hole 54. That is, two separators 50 are formed in a bag shape and enclose one positive electrode 20.

樹脂層５２には、セパレータ３０の場合と同様に、例えばポリエチレン、ポリプロピレン等のオレフィン系樹脂、セルロース等を主成分とする微多孔薄膜、織布、不織布などが用いられる。無機物層５３は、Ｔｉ、Ａｌ、Ｓｉ、Ｍｇ等の金属元素を含有する酸化物、炭化物、窒化物、ホウ化物、リン酸化合物などの無機化合物から構成され、一般的にセラミック層とも呼ばれる。無機物層５３は、例えば無機化合物を含有するスラリーをセパレータ５０の表面に塗布して形成することができる。なお、電極体４２では、各々の無機物層５３が対向した状態で正極２０を挟む２枚のセパレータ５０が重ね合わされるため、各セパレータ５０を溶着させることができない。ゆえに、各セパレータ５０は、端部に形成された貫通孔５４に接着剤５５を充填することで互いに接合される。   As in the case of the separator 30, for example, an olefin resin such as polyethylene or polypropylene, a microporous thin film mainly composed of cellulose, a woven fabric, a nonwoven fabric, or the like is used for the resin layer 52. The inorganic layer 53 is made of an inorganic compound such as an oxide, carbide, nitride, boride, or phosphate compound containing a metal element such as Ti, Al, Si, or Mg, and is generally called a ceramic layer. The inorganic layer 53 can be formed, for example, by applying a slurry containing an inorganic compound to the surface of the separator 50. In the electrode body 42, since the two separators 50 sandwiching the positive electrode 20 are overlapped with the inorganic layers 53 facing each other, the separators 50 cannot be welded. Therefore, the separators 50 are joined to each other by filling the through holes 54 formed at the ends with the adhesive 55.

貫通孔５４は、正極リード２１と重なる範囲を除く正極２０の周囲において、略等間隔で一列に形成されている。貫通孔５４の列は、正極２０の長辺又は短辺と略平行に形成され、列を構成する各貫通孔５４の間隔は、例えば０．１ｍｍ〜１ｍｍである。正極２０を挟む２枚のセパレータ５０は、上述の通り一方のセパレータ５０の各貫通孔５４と、他方のセパレータ５０の各貫通孔５４とが電極体４２の厚み方向に一致するように重ね合わされる。そして、各貫通孔５４に充填された接着剤５５により互いに接合される。   The through holes 54 are formed in a line at substantially equal intervals around the positive electrode 20 excluding a range overlapping with the positive electrode lead 21. The row | line | column of the through-hole 54 is formed substantially in parallel with the long side or short side of the positive electrode 20, and the space | interval of each through-hole 54 which comprises a row | line is 0.1 mm-1 mm, for example. As described above, the two separators 50 sandwiching the positive electrode 20 are overlapped so that each through hole 54 of one separator 50 and each through hole 54 of the other separator 50 coincide with the thickness direction of the electrode body 42. . Then, they are joined to each other by an adhesive 55 filled in each through hole 54.

接着剤５５は、セパレータ５０の表面に対する接着性が良好で、耐電解液性に優れる樹脂を主成分とすることが好ましい。好適な樹脂としては、セパレータ３０の突起３１の場合と同様に、ポリエチレン、ポリプロピレン等のオレフィン系樹脂、ポリテトラフルオロエチレン（ＰＴＦＥ）、ポリフッ化ビニリデン（ＰＶｄＦ）等のフッ素系樹脂が挙げられる。   The adhesive 55 is preferably composed mainly of a resin that has good adhesion to the surface of the separator 50 and is excellent in resistance to electrolyte. Suitable resins include olefin resins such as polyethylene and polypropylene, and fluorine resins such as polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVdF), as in the case of the protrusions 31 of the separator 30.

セパレータ５０の表面には、電極体４２の正面視において正極２０を取り囲むように樹脂製の突起５１が形成される点で、セパレータ３０の場合と共通する。突起５１は、電極体４２の厚み方向に負極２５と重なる位置に形成されている。また、突起５１は、セパレータ５０の負極２５側に向いた面であって正極２０の端から外側に張り出した負極２５の端部と対向する位置に、正極２０の長辺又は短辺と略平行に形成されている。突起５１は、正極２０のバリ２２と負極２５の接触により発生し得る内部短絡を防止すると共に、２枚のセパレータ５０の非接着部の開きを抑制する。２枚のセパレータ５０の突起５１が電極体４２の厚み方向の両側から負極２５に圧迫されることで非接着部が閉じられ、非接着部からの正極２０の露出による短絡、正極合材の浮遊片による微小短絡が抑制される。   The surface of the separator 50 is common to the separator 30 in that a resin protrusion 51 is formed so as to surround the positive electrode 20 in a front view of the electrode body 42. The protrusion 51 is formed at a position overlapping the negative electrode 25 in the thickness direction of the electrode body 42. Further, the protrusion 51 is a surface facing the negative electrode 25 side of the separator 50 and is substantially parallel to the long side or the short side of the positive electrode 20 at a position facing the end of the negative electrode 25 protruding outward from the end of the positive electrode 20. Is formed. The protrusion 51 prevents an internal short circuit that may occur due to the contact between the burr 22 of the positive electrode 20 and the negative electrode 25, and suppresses the opening of the non-adhesive portion of the two separators 50. The protrusions 51 of the two separators 50 are pressed against the negative electrode 25 from both sides in the thickness direction of the electrode body 42 to close the non-adhered part, short circuit due to the exposure of the positive electrode 20 from the non-adhered part, and floating of the positive electrode mixture Small short-circuiting by the piece is suppressed.

一方、突起５１は、各貫通孔５４の間において接着剤５５により形成される。即ち、各貫通孔５４に充填される接着剤５５は、セパレータ５０の表面上にも存在して突起５１を形成する。貫通孔５４に充填される接着剤５５と突起５１を形成する接着剤５５は同じものであり、貫通孔５４から食み出した接着剤５５が突起５１を形成しているといえる。突起５１は、正極リード２１と重なる範囲を除く正極２０の周囲において、正極２０を取り囲むように連続的に形成されている。但し、貫通孔５４が形成された部分で突起５１が窪んでいる。突起５１は、各貫通孔５４の間で高さが高く、貫通孔５４が形成された部分で高さが低くなった凹凸形状を有する。   On the other hand, the protrusion 51 is formed by an adhesive 55 between the through holes 54. That is, the adhesive 55 filling each through hole 54 is also present on the surface of the separator 50 to form the protrusion 51. The adhesive 55 filling the through hole 54 and the adhesive 55 forming the protrusion 51 are the same, and it can be said that the adhesive 55 protruding from the through hole 54 forms the protrusion 51. The protrusion 51 is continuously formed so as to surround the positive electrode 20 around the positive electrode 20 except for a range overlapping with the positive electrode lead 21. However, the protrusion 51 is recessed at the portion where the through hole 54 is formed. The protrusion 51 has a concavo-convex shape in which the height is high between the through holes 54 and the height is lowered in the portion where the through holes 54 are formed.

突起５１の高さｈ51は、各貫通孔５４の間において、例えば正極２０の厚みｔ20の半分（１／２）以下であり、好ましくは厚みｔ20の１／５〜１／２、より好ましくは厚みｔ20の１／３〜１／２であり、特に好ましくは厚みｔ20の略半分（略１／２）である。高さｈ51は、例えば５０μｍ〜１００μｍである。突起５１の凹凸のピッチ（各貫通孔５４の間に位置する凸部同士の間隔）は、貫通孔５４の間隔に対応しており、例えば０．１ｍｍ〜１ｍｍである。突起５１の凸部は、例えば長さ５ｍｍ〜１５ｍｍ、幅０．１ｍｍ〜１ｍｍで形成される。 The height h 51 of the protrusion 51 is, for example, not more than half (1/2) of the thickness t 20 of the positive electrode 20 between each through hole 54, preferably 1/5 to 1/2 of the thickness t 20. preferably 1 / 3-1 / 2 of the thickness t 20, and particularly preferably substantially half the thickness t 20 (about 1/2). The height h 51 is, for example, 50 μm to 100 μm. The pitch of the projections and depressions of the protrusions 51 (the interval between the protrusions located between the through holes 54) corresponds to the interval between the through holes 54, and is, for example, 0.1 mm to 1 mm. The protrusions of the protrusions 51 are formed with a length of 5 mm to 15 mm and a width of 0.1 mm to 1 mm, for example.

図７は、電極体４２の製造工程を説明するための図である。図７に例示するように、電極体４２の製造工程は、正極２０を挟むように２枚のセパレータ５０を重ね合わせた後、正極２０を取り囲むように各セパレータ５０を樹脂糸５６で縫い合わせ、樹脂糸５６を加熱溶融させる工程を備える。貫通孔５４は、各セパレータ５０を縫い合わせるときに形成されてもよいが、好ましくは縫い合わせる前に形成されており、貫通孔５４内で一方のセパレータ５０側から挿入される樹脂糸５６と他方のセパレータ５０側から挿入される樹脂糸５６が絡み合う。   FIG. 7 is a diagram for explaining a manufacturing process of the electrode body 42. As illustrated in FIG. 7, in the manufacturing process of the electrode body 42, two separators 50 are overlapped so as to sandwich the positive electrode 20, and then each separator 50 is sewn with a resin thread 56 so as to surround the positive electrode 20. A step of heating and melting the yarn 56; The through hole 54 may be formed when the separators 50 are stitched together, but is preferably formed before stitching, and the resin thread 56 inserted from the one separator 50 side in the through hole 54 and the other separator are formed. The resin yarn 56 inserted from the 50 side is entangled.

樹脂糸５６は、熱プレス等により加熱溶融されることで貫通孔５４に隙間なく充填される。そして、各セパレータ５０に密着してセパレータ５０同士を接合する接着剤５５となる。このため、樹脂糸５６にはポリオレフィン系樹脂等から構成される糸が用いられる。そして、セパレータ５０の表面には、正極２０よりも外側で負極２５と重なる位置に、加熱溶融した樹脂糸５６によって突起５１が形成される。樹脂糸５６の太さは、例えば正極２０の厚みｔ20の半分（１／２）以下であり、特に好ましくは厚みｔ20の略半分（略１／２）である。なお、樹脂糸５６を用いる代わりに、例えば各セパレータ５０を重ね合せた後、その表面に、加熱溶融した接着剤５５、又は接着剤５５を溶剤に溶解した樹脂溶液を塗工してもよい。 The resin yarn 56 is filled in the through hole 54 without a gap by being heated and melted by a hot press or the like. And it becomes the adhesive agent 55 which adhere | attaches each separator 50 and joins the separators 50 mutually. For this reason, as the resin yarn 56, a yarn composed of polyolefin resin or the like is used. A protrusion 51 is formed on the surface of the separator 50 by the heat-melted resin yarn 56 at a position overlapping the negative electrode 25 outside the positive electrode 20. The thickness of the resin thread 56 is, for example, not more than half (1/2) of the thickness t 20 of the positive electrode 20, and is particularly preferably approximately half (approximately 1/2) of the thickness t 20 . Instead of using the resin yarn 56, for example, after the separators 50 are overlapped, a heat-melted adhesive 55 or a resin solution in which the adhesive 55 is dissolved in a solvent may be applied to the surface.

１０ 非水電解質二次電池、１１ 外装体、１２，４２ 電極体、１３ 収容部、１４ 封止部、１５ 正極端子、１６ 負極端子、２０ 正極、２１ 正極リード、２２ バリ、２５ 負極、２６ 負極リード、３０，５０ セパレータ、３１，５１ 突起、５２ 樹脂層、５３ 無機物層、５４ 貫通孔、５５ 接着剤、５６ 樹脂糸   DESCRIPTION OF SYMBOLS 10 Nonaqueous electrolyte secondary battery, 11 exterior body, 12, 42 electrode body, 13 accommodating part, 14 sealing part, 15 positive electrode terminal, 16 negative electrode terminal, 20 positive electrode, 21 positive electrode lead, 22 burr | flash, 25 negative electrode, 26 negative electrode Lead, 30, 50 Separator, 31, 51 Protrusion, 52 Resin layer, 53 Inorganic layer, 54 Through hole, 55 Adhesive, 56 Resin yarn

Claims (6)

正極、負極、及びセパレータをそれぞれ複数含み、前記正極及び前記負極が前記セパレータを介して交互に積層された電極体を備える非水電解質二次電池であって、
前記負極及び前記セパレータは、前記正極よりも大きく、
前記セパレータの表面には、前記正極よりも外側で前記負極と重なる位置に、前記正極を取り囲むように樹脂製の突起が形成されている、非水電解質二次電池。 A non-aqueous electrolyte secondary battery comprising a plurality of positive electrodes, negative electrodes, and separators each including an electrode body in which the positive electrodes and the negative electrodes are alternately stacked via the separators,
The negative electrode and the separator are larger than the positive electrode,
A nonaqueous electrolyte secondary battery in which a resin protrusion is formed on the surface of the separator so as to surround the positive electrode at a position overlapping the negative electrode outside the positive electrode. 前記突起の高さは、前記正極の厚みの半分以下である、請求項１に記載の非水電解質二次電池。   The non-aqueous electrolyte secondary battery according to claim 1, wherein the height of the protrusion is not more than half of the thickness of the positive electrode. 前記突起が複数形成されており、
前記複数の突起間の距離が１ｍｍ以下である、請求項１又は２に記載の非水電解質二次電池。 A plurality of the protrusions are formed;
The nonaqueous electrolyte secondary battery according to claim 1 or 2, wherein a distance between the plurality of protrusions is 1 mm or less. 前記セパレータは、
前記正極と対向する面に形成された無機物層と、
前記正極よりも外側に形成された複数の貫通孔と、
を有し、
前記正極を挟む２枚の前記セパレータは、それぞれの前記各貫通孔が前記電極体の厚み方向に重なるように積層され、前記各貫通孔に充填された接着剤により互いに接合されている、請求項１〜３のいずれか１項に記載の非水電解質二次電池。 The separator is
An inorganic layer formed on the surface facing the positive electrode;
A plurality of through holes formed outside the positive electrode;
Have
The two separators sandwiching the positive electrode are laminated such that the respective through holes overlap in the thickness direction of the electrode body, and are joined to each other by an adhesive filled in the through holes. The nonaqueous electrolyte secondary battery according to any one of 1 to 3. 前記突起は、前記各貫通孔の間において前記接着剤により形成されている、請求項４に記載の非水電解質二次電池。   The non-aqueous electrolyte secondary battery according to claim 4, wherein the protrusion is formed by the adhesive between the through holes. 正極、前記正極よりも大きな負極、及び前記正極よりも大きなセパレータをそれぞれ複数含み、前記正極及び前記負極が前記セパレータを介して交互に積層された電極体を備える非水電解質二次電池の製造方法であって、
前記正極を挟むように２枚の前記セパレータを重ね合わせた後、前記正極を取り囲むように当該各セパレータを樹脂糸で縫い合わせ、当該樹脂糸を加熱溶融させる工程を備え、
前記セパレータの表面には、前記工程により、前記正極よりも外側で前記負極と重なる位置に、前記樹脂糸によって突起が形成される、非水電解質二次電池の製造方法。 A method for producing a non-aqueous electrolyte secondary battery comprising a positive electrode, a negative electrode larger than the positive electrode, and a plurality of separators larger than the positive electrode, each comprising an electrode body in which the positive electrode and the negative electrode are alternately stacked via the separator Because
After stacking the two separators so as to sandwich the positive electrode, the step of sewing the separators with resin yarns so as to surround the positive electrode, and heating and melting the resin yarns,
A method for producing a non-aqueous electrolyte secondary battery, wherein a protrusion is formed on the surface of the separator by the resin thread at a position overlapping the negative electrode outside the positive electrode by the step.
JP2016007799A 2016-01-19 2016-01-19 Nonaqueous electrolyte secondary battery and method of manufacturing nonaqueous electrolyte secondary battery Pending JP2017130301A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020102418A (en) * 2018-12-25 2020-07-02 プライムアースＥｖエナジー株式会社 Manufacturing method of electrode plate group for secondary battery, electrode plate group for secondary battery, and secondary battery
CN113632308A (en) * 2019-05-22 2021-11-09 株式会社Lg新能源 Separator laminate for lithium secondary battery, electrode assembly including the same, and lithium secondary battery including the same
JP2022519361A (en) * 2019-05-22 2022-03-23 エルジー エナジー ソリューション リミテッド Separation membrane laminate for lithium secondary battery, electrode assembly including this and lithium secondary battery

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020102418A (en) * 2018-12-25 2020-07-02 プライムアースＥｖエナジー株式会社 Manufacturing method of electrode plate group for secondary battery, electrode plate group for secondary battery, and secondary battery
CN113632308A (en) * 2019-05-22 2021-11-09 株式会社Lg新能源 Separator laminate for lithium secondary battery, electrode assembly including the same, and lithium secondary battery including the same
JP2022519361A (en) * 2019-05-22 2022-03-23 エルジー エナジー ソリューション リミテッド Separation membrane laminate for lithium secondary battery, electrode assembly including this and lithium secondary battery
JP7276970B2 (en) 2019-05-22 2023-05-18 エルジー エナジー ソリューション リミテッド Separation membrane laminate for lithium secondary battery, electrode assembly including the same, and lithium secondary battery

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