JP5555676B2

JP5555676B2 - Cylindrical secondary battery

Info

Publication number: JP5555676B2
Application number: JP2011191552A
Authority: JP
Inventors: 匡内藤; 英毅篠原
Original assignee: Hitachi Vehicle Energy Ltd
Current assignee: Vehicle Energy Japan Inc
Priority date: 2011-09-02
Filing date: 2011-09-02
Publication date: 2014-07-23
Anticipated expiration: 2031-09-02
Also published as: JP2013054880A

Description

この発明は、円筒形二次電池に関し、より詳細には、電極群の軸芯が集電部材に取付けられた円筒形二次電池に関する。 The present invention relates to a cylindrical secondary battery, and more particularly to a cylindrical secondary battery in which an axial core of an electrode group is attached to a current collecting member.

リチウム二次電池等に代表される円筒形二次電池は、円筒形の電池容器内に、長尺状の正極電極と負極電極とがセパレータを介して軸芯の周囲に捲回された電極群が収容され、電解液が注入されて構成されている。正・負極の電極は、それぞれ、正・負極の金属箔の両面に塗工された正・負極の活物質を有する。正・負極の金属箔は、それぞれ、長手方向の片側縁に沿って所定のピッチで配列された多数の正・負極タブを有する。正・負極タブは、互いに、正・負極の金属箔の反対側の片側縁に沿って形成される。 A cylindrical secondary battery typified by a lithium secondary battery is an electrode group in which a long positive electrode and a negative electrode are wound around a shaft core via a separator in a cylindrical battery container. Is contained and an electrolyte is injected. The positive and negative electrodes have positive and negative active materials coated on both sides of the positive and negative metal foils, respectively. Each of the positive and negative metal foils has a large number of positive and negative electrode tabs arranged at a predetermined pitch along one side edge in the longitudinal direction. The positive / negative electrode tabs are formed along one side edge of the opposite side of the positive / negative electrode metal foil.

円筒形二次電池の電池容器は、電池蓋によりガスケットと言われる絶縁材を介して電池缶を密封して構成されている。負極タブは、リング状の負極集電部材の外周側壁に溶接等により接合されており、負極集電部材は、負極導電リードを介して電池缶の缶底に固定されている。 A battery container of a cylindrical secondary battery is configured by sealing a battery can with a battery lid through an insulating material called a gasket. The negative electrode tab is joined to the outer peripheral side wall of the ring-shaped negative electrode current collector member by welding or the like, and the negative electrode current collector member is fixed to the bottom of the battery can via the negative electrode conductive lead.

負極集電部材の中央部には開口部が形成され、軸芯は負極集電部材の開口部に圧入されて取り付けられている。軸芯の外周面および負極集電部材の開口部の周側面のどちらも平坦面である（例えば、特許文献１参照）。 An opening is formed in the central portion of the negative electrode current collector, and the shaft core is press-fitted and attached to the opening of the negative electrode current collector. Both the outer peripheral surface of the shaft core and the peripheral side surface of the opening of the negative electrode current collecting member are flat surfaces (see, for example, Patent Document 1).

特開２００９−２８９６８３号公報JP 2009-289683 A

このように、従来においては、軸芯の保持は、軸芯と負極集電リングの圧入面がどちらも平坦面とされた圧接によるものである。車両などに搭載された円筒形二次電池には、あらゆる方向からの振動が作用する。軸芯には正・負極の電極が捲回されており、軸芯と負極集電リングとの取付部には、軸芯の軸方向の振動等により電極群の負荷が作用する。
このため、負極集電部材と軸芯との取付部が共に平坦面とされた圧接では電極群を保持するに十分でなく、負極集電部材に対して軸芯が軸方向に移動し、これに伴い、正・負極集電部材に接合された負極タブや負極金属箔が破断する恐れがあった。 As described above, conventionally, the shaft core is held by pressure contact in which both the shaft core and the press-fitting surface of the negative electrode current collection ring are flat surfaces. Vibration from all directions acts on the cylindrical secondary battery mounted on a vehicle or the like. Positive and negative electrodes are wound on the shaft core, and the load of the electrode group acts on the mounting portion between the shaft core and the negative electrode current collecting ring due to vibration in the axial direction of the shaft core.
For this reason, the pressure contact in which the attachment portions of the negative electrode current collecting member and the shaft core are both flat is not sufficient to hold the electrode group, and the shaft core moves in the axial direction with respect to the negative electrode current collecting member. As a result, the negative electrode tab and the negative electrode metal foil joined to the positive / negative current collecting member may be broken.

本発明の円筒形二次電池は、円筒状の軸芯の周囲に正極電極と負極電極とをセパレータを介して捲回した電極群と、電極群が収容され、電解液が注入された電池缶と、電池缶の一端側に配置されて電池缶を封止する電池蓋と、正極電極および負極電極の一方が接続されると共に、電池缶の缶底に固定されたリング状の集電部材とを備え、集電部材は複数の突起を有し、軸芯は集電部材の各突起に係合する切欠きを有し、各切欠きは、軸芯の先端面に開口する案内部と、案内部に連通する保持部とを有し、保持部は案内部との境界面から係合方向に突き出す係合凹部を有し、集電部材の各突起は、境界面よりも保持部の係合凹部側に突き出し、かつ、係合方向の長さが係合凹部の長さ以下の係合用突出部を有することを特徴とする。 The cylindrical secondary battery of the present invention is a battery can in which a positive electrode and a negative electrode are wound around a cylindrical shaft core through a separator, an electrode group is accommodated, and an electrolyte is injected A battery lid that is disposed on one end of the battery can and seals the battery can; one of the positive electrode and the negative electrode is connected, and a ring-shaped current collector fixed to the bottom of the battery can; The current collecting member has a plurality of protrusions, the shaft core has a notch that engages with each protrusion of the current collecting member, and each notch has a guide portion that opens to the front end surface of the shaft core; A holding portion that communicates with the guide portion, the holding portion has an engaging recess protruding in an engaging direction from a boundary surface with the guide portion, and each protrusion of the current collecting member is engaged with the holding portion more than the boundary surface. It has an engagement protrusion that protrudes toward the mating recess and has a length in the engagement direction equal to or less than the length of the engagement recess.

この発明の円筒形二次電池によれば、電部材の突起が保持部に係合された状態で保持部と案内部との境界面の幅は突起の幅より小さいので確実に集電部材により軸芯を確実に保持することができる。 According to the cylindrical secondary battery of the present invention, the width of the boundary surface between the holding portion and the guide portion is smaller than the width of the protrusion in a state where the protrusion of the electric member is engaged with the holding portion. The shaft core can be securely held.

本発明に係る円筒形二次電池の一実施の形態を示す断面図。Sectional drawing which shows one Embodiment of the cylindrical secondary battery which concerns on this invention. 図１に示された円筒形二次電池の分解斜視図。FIG. 2 is an exploded perspective view of the cylindrical secondary battery shown in FIG. 1. 図１に図示された軸芯と負極集電部材との分解斜視図。FIG. 2 is an exploded perspective view of the shaft core and the negative electrode current collector shown in FIG. 1. 図１の領域ＩＶの拡大断面図。The expanded sectional view of the area | region IV of FIG. 図１に図示された軸芯が係合された負極集電部材の平面図。The top view of the negative electrode current collection member with which the axial center shown in FIG. 1 was engaged. 図５の領域ＶＩの拡大図。The enlarged view of the area | region VI of FIG. 軸芯の切欠きの構造を示し、（ａ）は、切欠きの長さ方向に沿う平面図、（ｂ）は、（ａ）のＡ−Ａ’に沿う断面図。The structure of the notch of an axial core is shown, (a) is a top view in alignment with the length direction of a notch, (b) is sectional drawing in alignment with A-A 'of (a). 本発明の実施形態２に係り、軸芯が係合された負極集電部材の平面図。The top view of the negative electrode current collection member in connection with Embodiment 2 of this invention with which the axial center was engaged. 本発明の実施形態２に係る軸芯の切欠き形状を示す側面図。The side view which shows the notch shape of the axial center which concerns on Embodiment 2 of this invention. 本発明の実施形態２に係る軸芯の切欠きの構造を示し、（ａ）は、切欠きの長さ方向に沿う平面図、（ｂ）は、（ａ）のＡ−Ａ’に沿う断面図。The structure of the notch of the axial core which concerns on Embodiment 2 of this invention is shown, (a) is a top view in alignment with the length direction of a notch, (b) is a cross section in alignment with AA 'of (a). Figure. 本発明の実施形態３に係り、軸芯が係合された負極集電部材の平面図。The top view of the negative electrode current collection member in connection with Embodiment 3 of this invention with which the shaft core was engaged. 本発明の実施形態３に係る軸芯の切欠き形状を示す側面図。The side view which shows the notch shape of the axial center which concerns on Embodiment 3 of this invention. 本発明の実施形態３に係る軸芯の切欠きの構造を示し、（ａ）は、切欠きの長さ方向に沿う平面図、（ｂ）は、（ａ）のＡ−Ａ’に沿う断面図。The structure of the notch of the axial core which concerns on Embodiment 3 of this invention is shown, (a) is a top view in alignment with the length direction of a notch, (b) is a cross section in alignment with AA 'of (a). Figure. 本発明の実施形態４に係る軸芯の切欠き形状を示す側面図。The side view which shows the notch shape of the axial center which concerns on Embodiment 4 of this invention. 実施形態４に係る軸芯の切欠きの構造を示し、（ａ）は、切欠きの長さ方向に沿う平面図、（ｂ）は、（ａ）のＡ−Ａ’に沿う断面図。The structure of the notch of the axial core which concerns on Embodiment 4 is shown, (a) is a top view in alignment with the length direction of a notch, (b) is sectional drawing in alignment with A-A 'of (a). 本発明の実施形態５に係る軸芯の切欠きの構造を示し、（ａ）は、切欠きの長さ方向に沿う平面図、（ｂ）は、（ａ）のＡ−Ａ’に沿う断面図。The structure of the notch of the axial core which concerns on Embodiment 5 of this invention is shown, (a) is a top view in alignment with the length direction of a notch, (b) is a cross section in alignment with AA 'of (a). Figure. 本発明の実施形態６に係る軸芯の切欠きの構造を示し、（ａ）は、切欠きの長さ方向に沿う平面図、（ｂ）は、（ａ）のＡ−Ａ’に沿う断面図。The structure of the notch of the axial core which concerns on Embodiment 6 of this invention is shown, (a) is a top view in alignment with the length direction of a notch, (b) is a cross section in alignment with AA 'of (a). Figure. 本発明の実施形態７に係る軸芯の切欠きの構造を示し、（ａ）は、切欠きの長さ方向に沿う平面図、（ｂ）は、（ａ）のＡ−Ａ’に沿う断面図。The structure of the notch of the axial core which concerns on Embodiment 7 of this invention is shown, (a) is a top view in alignment with the length direction of a notch, (b) is a cross section in alignment with AA 'of (a). Figure.

（実施形態１）
--円筒形二次電池の構造--
以下、この発明の円筒形二次電池の一実施の形態を図面と共に説明する。
図１は、この発明の円筒形二次電池の一実施の形態を示す拡大断面図である。
円筒形二次電池１は、例えば、リチウムイオン二次電池である。この円筒形二次電池１は、上部が開口された円筒形の電池缶２および電池缶２の上部を封口するハット型の電池蓋３で構成される電池容器の内部に、以下に説明する発電用の各構成部材が収容され、非水電解液５が注入されて構成されている。 (Embodiment 1)
--Structure of cylindrical secondary battery--
Hereinafter, an embodiment of a cylindrical secondary battery of the present invention will be described with reference to the drawings.
FIG. 1 is an enlarged cross-sectional view showing an embodiment of a cylindrical secondary battery of the present invention.
The cylindrical secondary battery 1 is, for example, a lithium ion secondary battery. The cylindrical secondary battery 1 includes a cylindrical battery can 2 having an upper opening and a hat-type battery lid 3 that seals the upper portion of the battery can 2 and generates power as described below. Each structural member is accommodated, and the non-aqueous electrolyte 5 is inject | poured and comprised.

円筒形の電池缶２は、例えば、鉄（ＳＰＣＣ）製であり、内外両面にはニッケルめっきが施されている。電池缶２には、上端側に設けられた開口部２ｂ側に電池缶２の内側に突き出した溝２ａが形成されている。
電池缶２の中央部には、電極群１０が配置されている。電極群１０は、軸方向に沿う中空部を有する細長い円筒形の軸芯１５と、軸芯１５の周囲にセパレータを介して捲回された正極電極および負極電極とを備える。 The cylindrical battery can 2 is made of, for example, iron (SPCC), and nickel plating is applied to both the inner and outer surfaces. In the battery can 2, a groove 2 a protruding to the inside of the battery can 2 is formed on the opening 2 b provided on the upper end side.
An electrode group 10 is disposed at the center of the battery can 2. The electrode group 10 includes an elongated cylindrical shaft core 15 having a hollow portion along the axial direction, and a positive electrode and a negative electrode wound around the shaft core 15 via a separator.

図２は、図１に示された円筒形二次電池の分解斜視図である。
図２に図示されるように、電極群１０は、軸芯１５の周囲に、正極電極１１、負極電極１２、およびセパレータ１３が順に捲回された構造を有する。
電極群１０の最外周側は負極電極１２およびその外周に捲回されたセパレータ１３となっている。最外周のセパレータ１３は、その終端部の側縁が接着テープ１９で止められる。 FIG. 2 is an exploded perspective view of the cylindrical secondary battery shown in FIG.
As shown in FIG. 2, the electrode group 10 has a structure in which a positive electrode 11, a negative electrode 12, and a separator 13 are wound around an axis 15 in order.
The outermost peripheral side of the electrode group 10 is a negative electrode 12 and a separator 13 wound around the outer periphery thereof. The outermost separator 13 has its side edge at the end thereof stopped by an adhesive tape 19.

正極電極１１は、アルミニウム箔により形成された長尺な形状を有し、正極金属箔１１ａと、この正極金属箔１１ａの両面に正極合剤が塗布された正極合剤処理部１１ｂを有する。正極金属箔１１ａの長手方向に延在する上方側の側縁は、正極合剤が塗布されずアルミニウム箔が露出した正極合剤未処理部１１ｃとなっている。正極合剤未処理部１１ｃには、軸芯１５の軸に沿って上方に突き出す多数の正極タブ１６が等間隔に形成されている。正極タブ１６は、正極合剤未処理部１１ｃの上部を、例えば、ロールカッタにより裁断されて形成される。 The positive electrode 11 has a long shape formed of an aluminum foil, and includes a positive electrode metal foil 11a and a positive electrode mixture treatment portion 11b in which a positive electrode mixture is applied to both surfaces of the positive electrode metal foil 11a. The upper side edge extending in the longitudinal direction of the positive electrode metal foil 11a is a positive electrode mixture untreated portion 11c in which the positive electrode mixture is not applied and the aluminum foil is exposed. A number of positive electrode tabs 16 protruding upward along the axis of the shaft core 15 are formed at equal intervals in the positive electrode mixture untreated portion 11c. The positive electrode tab 16 is formed by cutting the upper portion of the positive electrode mixture untreated portion 11c with, for example, a roll cutter.

正極合剤は正極活物質と、正極導電材と、正極バインダとからなる。正極活物質はリチウム酸化物が好ましい。一例として、コバルト酸リチウム、マンガン酸リチウム、ニッケル酸リチウム、リチウム複合酸化物（コバルト、ニッケル、マンガンから選ばれる２種類以上を含むリチウム酸化物）等が挙げられる。 The positive electrode mixture includes a positive electrode active material, a positive electrode conductive material, and a positive electrode binder. The positive electrode active material is preferably lithium oxide. As an example, lithium cobaltate, lithium manganate, lithium nickelate, lithium composite oxide (lithium oxide containing two or more selected from cobalt, nickel, and manganese) can be given.

正極バインダは、正極活物質と正極導電材を結着させ、また正極合剤と正極集電体を結着させることが可能であり、非水電解液５との接触により、大幅に劣化しなければ特に制限はない。正極バインダの例としてポリフッ化ビニリデン（ＰＶＤＦ）やフッ素ゴムなどが挙げられる。 The positive electrode binder can bind the positive electrode active material and the positive electrode conductive material, and can bind the positive electrode mixture and the positive electrode current collector, and must be significantly deteriorated by contact with the non-aqueous electrolyte 5. There are no particular restrictions. Examples of the positive electrode binder include polyvinylidene fluoride (PVDF) and fluororubber.

負極電極１２は、銅箔により形成された長尺な形状を有し、負極金属箔１２ａと、この負極金属箔１２ａの両面に負極合剤が塗布された負極合剤処理部１２ｂを有する。負極金属箔１２ａの長手方向に延在する下方側の側縁は、負極合剤が塗布されず銅箔が露出した負極合剤未処理部１２ｃとなっている。この負極合剤未処理部１２ｃには、軸芯１５の軸に沿って正極タブ１６とは反対方向に延出された多数の負極タブ１７が等間隔に形成されている。負極タブ１７は、負極合剤未処理部１２ｃの上部を、例えば、ロールカッタにより裁断されて形成される。 The negative electrode 12 has a long shape formed of copper foil, and includes a negative electrode metal foil 12a and a negative electrode mixture treatment portion 12b in which a negative electrode mixture is applied to both surfaces of the negative electrode metal foil 12a. The lower side edge extending in the longitudinal direction of the negative electrode metal foil 12a is a negative electrode mixture untreated portion 12c where the negative electrode mixture is not applied and the copper foil is exposed. A large number of negative electrode tabs 17 extending in the direction opposite to the positive electrode tab 16 along the axis of the shaft core 15 are formed at equal intervals in the negative electrode mixture untreated portion 12c. The negative electrode tab 17 is formed by cutting the upper portion of the negative electrode mixture untreated portion 12c with, for example, a roll cutter.

負極合剤は、負極活物質と、負極バインダと、増粘剤とからなる。負極合剤は、アセチレンブラックなどの負極導電材を有しても良い。負極活物質としては、黒鉛炭素を用いること、特に人造黒鉛を使用することが好ましい。 The negative electrode mixture includes a negative electrode active material, a negative electrode binder, and a thickener. The negative electrode mixture may have a negative electrode conductive material such as acetylene black. As the negative electrode active material, it is preferable to use graphitic carbon, particularly artificial graphite.

セパレータ１３は、例えば、厚さ４０μｍの絶縁材料からなる多孔膜で形成されている。
中空部１５ｂを有する円筒形状とされた軸芯１５の上端部には、正極集電部材２７が取り付けられている。正極集電部材２７は、例えば、アルミニウムにより形成され、中央部には円形の開口部２７ａ（図１参照）が設けられている。開口部２７ａの周縁部には、軸芯１５側に突き出す内周側壁２７ｂ（図１参照）が、また、外周側には内周側壁２７ｂと逆方向に突き出す外周側壁２７ｃが形成されている。正極集電部材２７の内周側壁２７ｂは、軸芯１５の上端部側における中空部１５ｂ側に設けられた溝１５ａに圧入されている。
正極金属箔１１ａの正極タブ１６は、すべて、正極集電部材２７の外周側壁２７ｃに、例えば、超音波溶接により接合される。 The separator 13 is formed of a porous film made of an insulating material having a thickness of 40 μm, for example.
A positive electrode current collecting member 27 is attached to an upper end portion of the shaft core 15 having a cylindrical shape having the hollow portion 15b. The positive electrode current collector 27 is made of, for example, aluminum, and a circular opening 27a (see FIG. 1) is provided at the center. An inner peripheral side wall 27b (see FIG. 1) that protrudes toward the axis 15 is formed at the peripheral edge of the opening 27a, and an outer peripheral side wall 27c that protrudes in the direction opposite to the inner peripheral side wall 27b is formed on the outer peripheral side. The inner peripheral side wall 27 b of the positive electrode current collecting member 27 is press-fitted into a groove 15 a provided on the hollow portion 15 b side on the upper end portion side of the shaft core 15.
All the positive electrode tabs 16 of the positive electrode metal foil 11a are joined to the outer peripheral side wall 27c of the positive electrode current collector 27 by, for example, ultrasonic welding.

軸芯１５の下端部には、ほぼリング状の負極集電部材２０が取り付けられている。負極集電部材２０は、例えば、銅により形成されている。負極集電部材２０は、複数の開口２８（図２参照）が形成された平坦部と、この平坦部の外周に、鍔状に形成された外周側壁２１を有する。外周側壁２１の外周面には、負極金属箔１２ａの負極タブ１７が溶接されている。負極金属箔１２ａの負極タブ１７は、すべて、負極集電部材２０の外周側壁２１に、例えば、超音波溶接等により溶接される。平坦部に形成された開口２８は、非水電解液５の流動性の確保および過充電等の際に電池内部に発生するガスのガス抜きを図るためのものである。 A substantially ring-shaped negative electrode current collecting member 20 is attached to the lower end portion of the shaft core 15. The negative electrode current collecting member 20 is made of, for example, copper. The negative electrode current collecting member 20 has a flat portion in which a plurality of openings 28 (see FIG. 2) are formed, and an outer peripheral side wall 21 formed in a bowl shape on the outer periphery of the flat portion. The negative electrode tab 17 of the negative electrode metal foil 12 a is welded to the outer peripheral surface of the outer peripheral side wall 21. The negative electrode tabs 17 of the negative electrode metal foil 12a are all welded to the outer peripheral side wall 21 of the negative electrode current collector 20 by, for example, ultrasonic welding. The opening 28 formed in the flat portion is for securing the fluidity of the non-aqueous electrolyte 5 and degassing the gas generated inside the battery when overcharged.

負極集電部材２０には突起２３が形成され、軸芯１５の下端部に設けられた保持部３２（図３参照）に係合している。負極集電部材と２０と軸芯１５との係合構造の詳細は後述する。 A protrusion 23 is formed on the negative electrode current collecting member 20 and is engaged with a holding portion 32 (see FIG. 3) provided at the lower end portion of the shaft core 15. Details of the engagement structure of the negative electrode current collecting member 20 and the shaft core 15 will be described later.

負極集電部材２０と電池缶２の缶底２ｃとの間には、ニッケルからなる負極導電リード４７が介装されている。負極導電リード４７の周縁部は抵抗溶接またはレーザ溶接等により負極集電部材２０に接合されている。 A negative electrode conductive lead 47 made of nickel is interposed between the negative electrode current collecting member 20 and the can bottom 2 c of the battery can 2. The peripheral edge portion of the negative electrode conductive lead 47 is joined to the negative electrode current collecting member 20 by resistance welding or laser welding.

正極集電部材２７の開口部２７ａには、負極集電部材２０を電池缶２の缶底２ｃに溶接するための電極棒（図示せず）が挿通される。電極棒を正極集電部材２７に形成された開口部２７ａから軸芯１５の中空部１５ｂに差し込み、その先端部で負極導電リード４７を電池缶２の缶底２ｃの内面に押し付けて抵抗溶接を行う。負極集電部材２０に接続されている電池缶２の缶底２ｃは一方の出力端子として用いられる。 An electrode rod (not shown) for welding the negative electrode current collecting member 20 to the can bottom 2 c of the battery can 2 is inserted into the opening 27 a of the positive electrode current collecting member 27. The electrode rod is inserted into the hollow portion 15b of the shaft core 15 from the opening portion 27a formed in the positive electrode current collecting member 27, and the negative electrode conductive lead 47 is pressed against the inner surface of the can bottom 2c of the battery can 2 at the tip portion to perform resistance welding. Do. The can bottom 2c of the battery can 2 connected to the negative electrode current collecting member 20 is used as one output terminal.

正極集電部材２７には、複数のアルミニウム箔が積層されて構成されたフレキシブルな接続リード４１が、その一端部を溶接されて接合されている。
正極集電部材２７の外周側壁２７ｃ上には、接続板４４および電池蓋３が配置されている。接続板４４は、アルミニウムで形成され、円盤形状を有する。接続板４４の上面には、図示はしないが、中心部の周囲に円形形状の薄肉とされた開裂弁が形成されている。開裂弁は、過充電等により、電池容器内にガスが発生した場合に内部ガスを放出するためのものであり、そのガス圧で開裂するように形成されている。 A flexible connection lead 41 configured by laminating a plurality of aluminum foils is joined to the positive electrode current collecting member 27 by welding one end thereof.
On the outer peripheral side wall 27 c of the positive electrode current collecting member 27, the connection plate 44 and the battery lid 3 are disposed. The connection plate 44 is made of aluminum and has a disk shape. On the upper surface of the connection plate 44, although not shown in the figure, a round and thin cleavage valve is formed around the center. The cleavage valve is for releasing internal gas when gas is generated in the battery container due to overcharge or the like, and is formed so as to be cleaved at the gas pressure.

電池蓋３は、鉄（ＳＰＣＣ）により形成されており、内外両面にニッケルめっきが施されている。電池蓋３は、その周縁部が接続板４４の周縁部によってかしめられ、図２に図示されるように接続板４４と一体化されている。接続リード４１を介して正極集電部材２７に接続された電池蓋３は、他方の出力端子として用いられる。 The battery lid 3 is made of iron (SPCC), and nickel plating is applied to both the inside and outside. The battery lid 3 is caulked at its peripheral edge by the peripheral edge of the connection plate 44 and integrated with the connection plate 44 as shown in FIG. The battery lid 3 connected to the positive electrode current collecting member 27 via the connection lead 41 is used as the other output terminal.

図１に図示されるように、電池蓋３が一体化された接続板４４の周縁部の上下両面はガスケット４５によって覆われている。ガスケット４５は、例えば、プルフルオロアルコキシフッ素樹脂（ＰＦＡ）等により形成されている。
ガスケット４５の周縁部は、図２に図示されるように、当初、ほぼ垂直に起立して形成されている。ガスケット４５の周縁部の内側に電池蓋３が一体化された接続板４４を配置し、プレス等により、電池缶２と共にガスケット４５の周縁部をかしめる。これにより、電池蓋３、接続板４４、ガスケット４５および電池缶２が一体化された密閉状の電池容器が構成される。 As shown in FIG. 1, the upper and lower surfaces of the peripheral portion of the connection plate 44 in which the battery lid 3 is integrated are covered with a gasket 45. The gasket 45 is made of, for example, a pull fluoroalkoxy fluororesin (PFA).
As shown in FIG. 2, the peripheral edge of the gasket 45 is initially formed to stand substantially vertically. A connecting plate 44 in which the battery lid 3 is integrated is arranged inside the peripheral edge of the gasket 45, and the peripheral edge of the gasket 45 is caulked together with the battery can 2 by pressing or the like. Thereby, a sealed battery container in which the battery lid 3, the connection plate 44, the gasket 45, and the battery can 2 are integrated is configured.

電池缶２の内部には、非水電解液５が所定量注入されている。非水電解液５の一例としては、リチウム塩がカーボネート系溶媒に溶解した溶液を用いることが好ましい。リチウム塩の例として、フッ化リン酸リチウム（ＬｉＰＦ_６）、フッ化ホウ酸リチウム（ＬｉＢＦ_６）、等が挙げられる。また、カーボネート系溶媒の例として、エチレンカーボネート（ＥＣ）、ジメチルカーボネート（ＤＭＣ）、プロピレンカーボネート（ＰＣ）、メチルエチルカーボネート（ＭＥＣ）、或いは上記溶媒の１種類以上から選ばれる溶媒を混合したものが挙げられる。 A predetermined amount of non-aqueous electrolyte 5 is injected into the battery can 2. As an example of the nonaqueous electrolytic solution 5, it is preferable to use a solution in which a lithium salt is dissolved in a carbonate solvent. Examples of the lithium salt include lithium fluorophosphate (LiPF ₆ ), lithium fluoroborate (LiBF ₆ ), and the like. Examples of carbonate solvents include ethylene carbonate (EC), dimethyl carbonate (DMC), propylene carbonate (PC), methyl ethyl carbonate (MEC), or a mixture of solvents selected from one or more of the above solvents. Can be mentioned.

図３は、図１に図示された軸芯と負極集電部材との分解斜視図であり、図４は、図１に図示された領域ＩＶの拡大断面図であり、図５は、図１に図示された軸芯が係合された負極集電部材の平面図である。
負極集電部材２０は平面視で円形の平坦部を有し、平坦部の外周縁には外周側壁２１が形成されている。平坦部の中央部には、軸芯１５を挿通する円形の開口部２２が形成されており、開口部２２の周囲には、複数の開口２８が形成されている。
開口部２２の周側面には、開口部２２の中心を通る一直線上に配置された一対の半球円形状の突起２３が形成されている。 3 is an exploded perspective view of the shaft core and the negative electrode current collecting member illustrated in FIG. 1, FIG. 4 is an enlarged cross-sectional view of a region IV illustrated in FIG. 1, and FIG. It is a top view of the negative electrode current collection member with which the shaft core shown in figure was engaged.
The negative electrode current collecting member 20 has a circular flat portion in plan view, and an outer peripheral side wall 21 is formed on the outer peripheral edge of the flat portion. A circular opening 22 through which the shaft core 15 is inserted is formed at the center of the flat part, and a plurality of openings 28 are formed around the opening 22.
A pair of hemispherical protrusions 23 arranged on a straight line passing through the center of the opening 22 are formed on the peripheral side surface of the opening 22.

軸芯１５には、電池缶２の缶底２ｃに対向する先端部側に、切欠き３０が形成されている。切欠き３０は、突起２３に対応する位置に一対形成されており、図３では、軸芯１５の一面側の１個のみ図示されているが、軸芯１５の裏面側にも形成されている。
各切欠き３０は、軸芯１５の厚さの中間に底面を有する溝状に形成されており、案内部３１と保持部３２とを有する。案内部３１は、軸芯１５の軸方向に対して傾斜する方向に、軸芯１５の外周面に沿って直線的に延出して形成され、一端は軸芯１５の先端面１５ｃに開通している。保持部３２は、その直径が案内部３１の幅よりも大きい円形形状に形成されており、円形の外周部の一部が案内部３１の他端に連通している。 A cutout 30 is formed in the shaft core 15 on the tip end side facing the can bottom 2 c of the battery can 2. A pair of notches 30 are formed at positions corresponding to the protrusions 23, and in FIG. 3, only one on the one surface side of the shaft core 15 is shown, but it is also formed on the back surface side of the shaft core 15. .
Each notch 30 is formed in a groove shape having a bottom surface in the middle of the thickness of the shaft core 15, and includes a guide portion 31 and a holding portion 32. The guide portion 31 is formed to extend linearly along the outer peripheral surface of the shaft core 15 in a direction inclined with respect to the axial direction of the shaft core 15, and one end is opened to the tip surface 15 c of the shaft core 15. Yes. The holding part 32 is formed in a circular shape whose diameter is larger than the width of the guide part 31, and a part of the circular outer peripheral part communicates with the other end of the guide part 31.

図６は、図５における領域ＶＩの拡大図であり、図７は、軸芯の切欠きの形状、構造を示し、図７（ａ）は切欠きの長さ方向に沿う平面図、図７（ｂ）は、図７（ａ）のＡ−Ａ’に沿う断面図である。図７（ａ）、（ｂ）において、負極集電部材２０の突起２３が二点鎖線で示されている。
図７（ｂ）に図示されるように、軸芯１５に形成された切欠き３０の案内部３１と保持部３２は、底面が平坦な溝状に形成されている。案内部３１と保持部３２の底面は、同一面、すなわち同一の深さに形成されている。
案内部３１と保持部３２とは、連通部である境界面を有しており、図７（ａ）に図示されるように、境界面の幅をＷ１、保持部３２の最大幅（直径）をＷ２とした場合、負極集電部材２０の突起２３の最大幅（直径）ｘは、Ｗ２≧ｘ＞Ｗ１とされている。
つまり、突起２３の幅ｘを、保持部３２の最大幅Ｗ２以下とし、かつ、境界面の幅Ｗ１よりも大きくする。このようにすると、突起２３と保持部３２とは係合し、突起２３が境界面から案内部３１に抜け出ることはない。
なお、図６においては、軸芯１５の外形と負極集電部材２０の開口部２２との間に、所定の空隙ｓが形成されている状態の断面図を示している。 6 is an enlarged view of the region VI in FIG. 5, FIG. 7 shows the shape and structure of the notch of the shaft core, FIG. 7A is a plan view along the length direction of the notch, FIG. (B) is sectional drawing which follows AA 'of Fig.7 (a). 7A and 7B, the protrusion 23 of the negative electrode current collecting member 20 is indicated by a two-dot chain line.
As shown in FIG. 7B, the guide portion 31 and the holding portion 32 of the notch 30 formed in the shaft core 15 are formed in a groove shape with a flat bottom surface. The bottom surfaces of the guide portion 31 and the holding portion 32 are formed on the same surface, that is, at the same depth.
The guide portion 31 and the holding portion 32 have a boundary surface that is a communication portion, and as shown in FIG. 7A, the width of the boundary surface is W1, and the maximum width (diameter) of the holding portion 32. Is W2, the maximum width (diameter) x of the protrusion 23 of the negative electrode current collecting member 20 is W2 ≧ x> W1.
That is, the width x of the protrusion 23 is set to be equal to or smaller than the maximum width W2 of the holding portion 32 and larger than the width W1 of the boundary surface. In this way, the projection 23 and the holding portion 32 are engaged, and the projection 23 does not come out from the boundary surface to the guide portion 31.
FIG. 6 is a cross-sectional view showing a state in which a predetermined gap s is formed between the outer shape of the shaft core 15 and the opening 22 of the negative electrode current collecting member 20.

軸芯１５と負極集電部材２０とを係合する方法を以下に示す。
負極集電部材２０の一対の突起２３を、軸芯１５の先端面１５ｃに開通されている一対の案内部３１に位置合わせする。負極集電部材２０は、例えば、開口２８に治具のピン部等（図示せず）を挿通し、回転止めをしておく。また、軸芯１５の中空部１５ｂには、スピンドル（図示せず）を挿通し、スピンドルと共に回転可能な状態にする。中空部１５ｂの断面形状は、円形形状を両側の側部で直線的に除去した平坦面を有する形状とされているため、断面が矩形形状のスピンドルを用いれば、軸芯１５を回転させることができる。軸芯１５の中空部１５ｂの断面が、円形形状のように、平坦面を有していない場合には、スピンドルに軸方向に平行なスリットを設け、スピンドルを円周方向に拓いて、軸芯１５の中空部１５ｂとの間の摩擦力により軸芯１５を回転させることができる。 A method for engaging the shaft core 15 and the negative electrode current collector 20 will be described below.
The pair of protrusions 23 of the negative electrode current collecting member 20 are aligned with the pair of guide portions 31 opened in the tip surface 15 c of the shaft core 15. The negative electrode current collecting member 20 is, for example, inserted into the opening 28 through a pin portion of a jig (not shown) and stopped in rotation. Further, a spindle (not shown) is inserted into the hollow portion 15b of the shaft core 15 so as to be rotatable together with the spindle. The cross-sectional shape of the hollow portion 15b is a shape having a flat surface obtained by linearly removing the circular shape at the sides on both sides. Therefore, if a spindle having a rectangular cross section is used, the shaft core 15 can be rotated. it can. When the cross section of the hollow portion 15b of the shaft core 15 does not have a flat surface, such as a circular shape, the spindle is provided with a slit parallel to the axial direction, and the spindle is opened in the circumferential direction. The shaft core 15 can be rotated by the frictional force between the 15 hollow portions 15b.

スピンドルを回転しながら負極集電部材２０の各突起２３を、軸芯１５の案内部３１に沿って押し込んでいく。突起２３の幅ｘは、案内部３１の幅Ｗ１より大きいので、案内部３１を幅方向に押し拡げながら案内部３１に沿って押し込み、保持部３２まで圧入する。突起２３が保持部３２のほぼ中央まで達すると、保持部３２の直径である最大幅Ｗ２は、突起２３の最大幅（直径）ｘ以上であるので、案内部３１は幅Ｗ１に復元する。 Each protrusion 23 of the negative electrode current collecting member 20 is pushed along the guide portion 31 of the shaft core 15 while rotating the spindle. Since the width x of the protrusion 23 is larger than the width W1 of the guide part 31, the guide part 31 is pushed in along the guide part 31 while being pushed in the width direction, and is pressed into the holding part 32. When the projection 23 reaches almost the center of the holding portion 32, the maximum width W2 that is the diameter of the holding portion 32 is equal to or larger than the maximum width (diameter) x of the projection 23, and thus the guide portion 31 is restored to the width W1.

この状態では、半球状の突起２３は、片側において、案内部３１と保持部３２の境界面の幅Ｗ１よりも、長さ（幅）Δｗ＝（ｘ−Ｗ１）/２だけ大きい。これにより、負極集電部材２０の突起２３と軸芯１５の保持部３２とが係合する。 In this state, the hemispherical protrusion 23 is larger on one side by a length (width) Δw = (x−W1) / 2 than the width W1 of the boundary surface between the guide portion 31 and the holding portion 32. Thereby, the protrusion 23 of the negative electrode current collecting member 20 and the holding portion 32 of the shaft core 15 are engaged.

負極集電部材２０の突起２３と、軸芯１５の切欠き３０とが係合する方向を係合方向とすれば、一実施の形態においては、係合方向は幅方向である。
そして、軸芯１５の保持部３２は、案内部３１との境界面における幅Ｗ１よりも係合方向に突き出す係合凹部を有している。片側における係合凹部の長さは、（Ｗ２−Ｗ１）/２である。また、負極集電部材２０の突起２３は、軸芯１５の保持部３２と案内部３１との境界面よりも係合方向に突き出す係合用突出部を有している。片側における係合用突出部の長さ（幅）Δｗ＝（ｘ−Ｗ１）/２である。Ｗ２≧ｘであるから、突起２３と保持部３２とが係合している状態では、保持部３２の幅は元の状態に復元しており、境界面においては幅Ｗ１となっている。この係合用突出部の長さが、負極集電部材２０の突起２３と軸芯１５の保持部３２とが係合する長さとなる。 If the direction in which the protrusion 23 of the negative electrode current collecting member 20 is engaged with the notch 30 of the shaft core 15 is the engagement direction, in the embodiment, the engagement direction is the width direction.
And the holding | maintenance part 32 of the shaft core 15 has the engagement recessed part which protrudes in an engagement direction rather than the width W1 in the boundary surface with the guide part 31. FIG. The length of the engaging recess on one side is (W2-W1) / 2. Further, the protrusion 23 of the negative electrode current collecting member 20 has an engaging protrusion that protrudes in the engaging direction from the boundary surface between the holding portion 32 of the shaft core 15 and the guide portion 31. The length (width) Δw = (x−W1) / 2 of the protrusion for engagement on one side. Since W2 ≧ x, the width of the holding portion 32 is restored to the original state in the state where the protrusion 23 and the holding portion 32 are engaged, and the width is W1 at the boundary surface. The length of this engaging protrusion is the length at which the protrusion 23 of the negative electrode current collector 20 and the holding portion 32 of the shaft core 15 are engaged.

本発明の一実施の形態によれば、負極集電部材２０の突起２３が保持部３２に係合された状態において、保持部３２と案内部３１との境界面の幅Ｗ１は、突起２３の係合方向における係合用突出部の幅より小さいので、負極集電部材２０により、確実に軸芯１５を保持することができる。従って、円筒形二次電池に軸方向の振動等の外力が作用しても、負極集電部材２０が軸芯１５の変位を制限し、負極タブ１７の破断等を防止することができる。 According to the embodiment of the present invention, in the state in which the protrusion 23 of the negative electrode current collecting member 20 is engaged with the holding part 32, the width W1 of the boundary surface between the holding part 32 and the guide part 31 is Since it is smaller than the width of the engaging protrusion in the engaging direction, the negative electrode current collecting member 20 can reliably hold the shaft core 15. Therefore, even if an external force such as axial vibration acts on the cylindrical secondary battery, the negative electrode current collecting member 20 can restrict the displacement of the shaft core 15 and prevent the negative electrode tab 17 from being broken.

上記実施形態においては、負極集電部材２０の突起２３の係合用突出部の長さ（幅）は、軸芯１５の保持部３２が、案内部３１との境界面から係合方向に突き出した係合凹部の長さ以下であるので、案内部３１の幅Ｗ１は、常に、元の状態に復元する。従って、突起２３の係合用突出部の長さは、常に、係合部分の長さ（幅）として確保される。
なお、負極タブ１７として純銅を用いる場合、純銅の伸びを５％とすれば、負極タブ１７の長さが５ｍｍの場合には、負極集電部材２０の保持部３２の大きさは、軸芯１５の軸方向への変位許容量が０．２５ｍｍ以下となるように設計する。 In the above embodiment, the length (width) of the protrusion for engagement of the protrusion 23 of the negative electrode current collecting member 20 is such that the holding portion 32 of the shaft core 15 protrudes from the boundary surface with the guide portion 31 in the engagement direction. Since it is below the length of the engagement recess, the width W1 of the guide portion 31 is always restored to the original state. Accordingly, the length of the engaging protrusion of the protrusion 23 is always ensured as the length (width) of the engaging portion.
In addition, when using pure copper as the negative electrode tab 17, if the elongation of pure copper is 5%, and the length of the negative electrode tab 17 is 5 mm, the size of the holding portion 32 of the negative electrode current collecting member 20 is the axial center. 15 is designed so that the allowable displacement in the axial direction is 0.25 mm or less.

（実施形態２）
図８は、本発明の実施形態２に係り、軸芯が係合された負極集電部材の平面図であり、図９は、実施形態２の軸芯の切欠き形状を示す側面図である。また、図１０は、本発明の実施形態２に係る軸芯の切欠きの構造を示し、図１０（ａ）は、切欠きの長さ方向に沿う平面図、図１０（ｂ）は、図１０（ａ）のＡ−Ａ’に沿う断面図である。図１０（ａ）、（ｂ）において、負極集電部材２０の突起２３が二点鎖線で示されている。
図８に図示されるように、実施形態２として示す軸芯１５には、外周面の３箇所に切欠き３０Ａが形成され、負極集電部材２０には、各切欠き３０Ａに係合する３つの突起２３が形成されている。 (Embodiment 2)
FIG. 8 is a plan view of the negative electrode current collecting member engaged with the shaft core according to the second embodiment of the present invention, and FIG. 9 is a side view showing the notch shape of the shaft core according to the second embodiment. . FIG. 10 shows the structure of a shaft core notch according to Embodiment 2 of the present invention, FIG. 10 (a) is a plan view along the length direction of the notch, and FIG. 10 (b) is a diagram. It is sectional drawing which follows AA 'of 10 (a). 10A and 10B, the protrusion 23 of the negative electrode current collecting member 20 is indicated by a two-dot chain line.
As illustrated in FIG. 8, the shaft core 15 shown as the second embodiment has notches 30 A formed at three locations on the outer peripheral surface, and the negative electrode current collecting member 20 is engaged with each notch 30 A 3. Two protrusions 23 are formed.

各切欠き３０Ａは、一端が、軸芯１５における電池缶２の缶底２ｃ側の先端面１５ｃに開通する第１の案内部３１ａ、この第１の案内部３１ａに連通する第２の案内部３１ｂと、この第２の案内部３１ｂに連通する保持部３２ａとを有する。
第１の案内部３１ａは、軸芯１５の先端面１５ｃ側が幅広い傾斜部を有し、軸芯１５の軸方向と平行に形成されている。第２の案内部３１ｂは、実施形態１と同様に、軸芯１５の軸方向に対して傾斜する方向に、軸芯１５の外周面に沿って直線的に延出して形成されている。
また、保持部３２ａは、最大幅が、第２の案内部３１ｂと同じで、延出方向が長軸となる楕円形に形成されている。 Each notch 30A has a first guide portion 31a having one end opened to the tip end surface 15c on the can bottom 2c side of the battery can 2 in the shaft core 15, and a second guide portion communicating with the first guide portion 31a. 31b and a holding portion 32a communicating with the second guide portion 31b.
The first guide portion 31 a has a wide inclined portion on the tip end surface 15 c side of the shaft core 15, and is formed in parallel with the axial direction of the shaft core 15. Similarly to the first embodiment, the second guide portion 31 b is formed to extend linearly along the outer peripheral surface of the shaft core 15 in a direction inclined with respect to the axial direction of the shaft core 15.
The holding portion 32a has the same maximum width as that of the second guide portion 31b, and is formed in an elliptical shape with the extending direction as the major axis.

図１０（ａ）、（ｂ）においては、第１の案内部３１ａは図示を省略されているが、第１の案内部３１ａと第２の案内部３１ｂとは同じ深さであり、また底面は平坦である。
図１０（ｂ）に図示されるように、保持部３２ａの深さは、第２の案内部３１ｂとの境界面よりも深く形成されている。境界面の深さをＤ１、保持部３２ａの最大深さをＤ２、とした場合、負極集電部材２０における突起２３の厚さｙは、Ｄ２≧ｙ＞Ｄ１とされている。
つまり、突起２３の厚さｙを、保持部３２ａの深さＤ２以下とし、かつ、境界面の深さＤ１よりも大きくする。
このようにすると、突起２３と保持部３２ａとは係合し、突起２３が境界面から案内部３１に抜け出ることはない。 In FIGS. 10A and 10B, the first guide portion 31a is not shown, but the first guide portion 31a and the second guide portion 31b have the same depth, and the bottom surface. Is flat.
As shown in FIG. 10B, the holding portion 32a is formed deeper than the boundary surface with the second guide portion 31b. When the depth of the boundary surface is D1 and the maximum depth of the holding portion 32a is D2, the thickness y of the protrusion 23 in the negative electrode current collecting member 20 satisfies D2 ≧ y> D1.
That is, the thickness y of the protrusion 23 is set to be equal to or less than the depth D2 of the holding portion 32a and larger than the depth D1 of the boundary surface.
If it does in this way, the protrusion 23 and the holding | maintenance part 32a will engage, and the protrusion 23 does not slip out to the guide part 31 from a boundary surface.

負極集電部材２０の突起２３と、軸芯１５の切欠き３０Ａとが係合する方向を係合方向とすれば、実施形態２においては、係合方向は深さ方向である。
そして、軸芯１５の保持部３２ａは、第２の案内部３１ｂとの境界面における深さＤ１よりも係合方向に突き出す係合凹部を有している。係合凹部の長さ（深さ）は、（Ｄ２−Ｄ１）である。また、負極集電部材２０の突起２３は、軸芯１５の保持部３２ａと第２の案内部３１ｂとの境界面よりも係合方向に突き出す係合用突出部を有している。係合用突出部の長さΔＤ＝（ｙ−Ｄ１）である。この係合用突出部の長さΔＤが、負極集電部材２０の突起２３と軸芯１５の保持部３２ａとが係合する長さとなる。 If the direction in which the protrusion 23 of the negative electrode current collecting member 20 is engaged with the notch 30A of the shaft core 15 is the engaging direction, the engaging direction is the depth direction in the second embodiment.
And the holding | maintenance part 32a of the shaft core 15 has the engagement recessed part which protrudes in an engagement direction rather than the depth D1 in the boundary surface with the 2nd guide part 31b. The length (depth) of the engaging recess is (D2-D1). Further, the protrusion 23 of the negative electrode current collecting member 20 has an engaging protrusion that protrudes in the engaging direction from the boundary surface between the holding portion 32 a of the shaft core 15 and the second guide portion 31 b. The length ΔD of the engaging protrusion is (y−D1). The length ΔD of the engaging protrusion is the length at which the protrusion 23 of the negative electrode current collecting member 20 and the holding portion 32a of the shaft core 15 are engaged.

本発明の実施形態２によれば、負極集電部材２０の突起２３が保持部３２ａに係合された状態において、保持部３２ａと第２の案内部３１ｂとの境界面の深さＤ１は、突起２３の係合方向における係合用突出部の深さより小さいので、負極集電部材２０により、確実に軸芯１５を保持することができる。従って、円筒形二次電池に軸方向の振動等が作用しても、負極集電部材２０が軸芯１５の変位を制限し、負極タブ１７の破断等を防止することができる。 According to the second embodiment of the present invention, in the state where the protrusion 23 of the negative electrode current collecting member 20 is engaged with the holding portion 32a, the depth D1 of the boundary surface between the holding portion 32a and the second guide portion 31b is Since the depth is smaller than the depth of the engaging protrusion in the engaging direction of the protrusion 23, the negative electrode current collecting member 20 can reliably hold the shaft core 15. Therefore, even if axial vibration or the like acts on the cylindrical secondary battery, the negative electrode current collecting member 20 can limit the displacement of the axial core 15 and prevent the negative electrode tab 17 from being broken.

上記実施形態２において、負極集電部材２０の突起２３の係合用突出部の長さ（深さ）は、軸芯１５の保持部３２ａと第２の案内部３１ｂとの境界面から係合方向に突き出した係合凹部の長さ（Ｄ２−Ｄ１）以下であるので、境界面の深さＤ１は、常に、元の状態に復元する。従って、突起２３の係合用突出部の長さは、常に、係合部分の長さとして確保され、実施形態１と同様な効果を奏する。 In the second embodiment, the length (depth) of the protrusion for engagement of the protrusion 23 of the negative electrode current collecting member 20 is the engagement direction from the boundary surface between the holding portion 32a of the shaft core 15 and the second guide portion 31b. Therefore, the depth D1 of the boundary surface is always restored to the original state. Accordingly, the length of the protrusion for engagement of the protrusion 23 is always ensured as the length of the engaging portion, and the same effect as in the first embodiment is obtained.

実施形態２においては、第１の案内部３１ａは、軸芯１５の先端面側が幅広の傾斜部を有しているので、負極集電部材２０の突起２３を、軸芯１５の切欠き２０に嵌入する際、第１の案内部３１ａの傾斜部が案内部となり、嵌入が容易となる。 In the second embodiment, the first guide portion 31 a has a wide inclined portion on the tip surface side of the shaft core 15, so that the protrusion 23 of the negative electrode current collecting member 20 is formed in the notch 20 of the shaft core 15. When inserting, the inclination part of the 1st guide part 31a turns into a guide part, and insertion becomes easy.

また、実施形態２においては、軸芯１５と負極集電部材２０との係合部が３箇所となっているので、係合部が２か所である実施形態１の場合に比し、振動等の外力を分散する効果が大きく、負極集電部材２０による軸芯１５の保持力を大きくすることができる。
なお、実施形態２において、実施形態１と同様な構成には、対応する構成に同じ符号を付し説明を省略する。 Further, in the second embodiment, since there are three engaging portions between the shaft core 15 and the negative electrode current collecting member 20, the vibration is less than in the case of the first embodiment having two engaging portions. The effect of dispersing external forces such as the above is great, and the holding force of the shaft core 15 by the negative electrode current collecting member 20 can be increased.
In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

（実施形態３）
図１１は、本発明の実施形態３に係り、軸芯が係合された負極集電部材の平面図であり、図１２は、実施形態３の軸芯の切欠き形状を示す側面図である。また、図１３は、本発明の実施形態３に係る軸芯の切欠きの構造を示し、図１３（ａ）は、切欠きの長さ方向に沿う平面図、図１３（ｂ）は、（ａ）のＡ−Ａ’に沿う断面図である。図１３（ａ）、（ｂ）において、負極集電部材２０の突起２３ａが二点鎖線で示されている。
図１１に図示されるように、実施形態３として示す軸芯１５には、外周面の４箇所に切欠き３０Ｂが形成され、負極集電部材２０には、切欠き３０Ｂに係合する４つの突起２３ａが形成されている。
切欠き３０Ｂおよび突起２３ａは、それぞれ、断面が矩形形状に形成されている。
なお、実施形態３における軸芯１５の中空部１５ｂは、断面が矩形形状に形成されている。 (Embodiment 3)
FIG. 11 is a plan view of a negative electrode current collecting member engaged with a shaft core according to the third embodiment of the present invention, and FIG. 12 is a side view showing a notch shape of the shaft core according to the third embodiment. . Moreover, FIG. 13 shows the structure of the notch of the axial core which concerns on Embodiment 3 of this invention, FIG.13 (a) is a top view in alignment with the length direction of a notch, FIG.13 (b) is ( It is sectional drawing which follows AA 'of a). 13A and 13B, the protrusion 23a of the negative electrode current collecting member 20 is indicated by a two-dot chain line.
As shown in FIG. 11, the shaft core 15 shown as the third embodiment has notches 30 B formed at four locations on the outer peripheral surface, and the negative electrode current collecting member 20 has four engagements with the notches 30 B. A protrusion 23a is formed.
Each of the cutout 30B and the protrusion 23a has a rectangular cross section.
In addition, the hollow part 15b of the shaft core 15 in Embodiment 3 is formed in a rectangular shape in cross section.

各切欠き３０Ｂは、第１の案内部３１ｃ、第２の案内部３１ｄ、第３の案内部３１ｅと、保持部３２ｂを有する。第１の案内部３１ｃは、軸芯１５の先端面１５ｃ側が幅広い傾斜部を有し、軸芯１５の軸方向と平行に形成されている。第２の案内部３１ｄは、実施形態１と同様に、軸芯１５の軸方向に対して傾斜する方向に、軸芯１５の外周面に沿って直線的に延出して形成されている。第１、第２の案内部３１ｃ、３１ｄは、断面が矩形形状である点を除けば、実施形態２と同様な構造である。第３の案内部３１ｅは、第２の案内部３１ｄに連通し、軸芯１５の軸方向と垂直な方向に、軸芯１５の外周面に沿って延出されている。 Each notch 30B includes a first guide portion 31c, a second guide portion 31d, a third guide portion 31e, and a holding portion 32b. The first guide portion 31 c has a wide inclined portion on the tip end surface 15 c side of the shaft core 15, and is formed in parallel with the axial direction of the shaft core 15. Similarly to the first embodiment, the second guide portion 31 d is formed to extend linearly along the outer peripheral surface of the shaft core 15 in a direction inclined with respect to the axial direction of the shaft core 15. The first and second guide portions 31c and 31d have the same structure as that of the second embodiment except that the cross section is rectangular. The third guide portion 31 e communicates with the second guide portion 31 d and extends along the outer peripheral surface of the shaft core 15 in a direction perpendicular to the axial direction of the shaft core 15.

保持部３２ｂは、第３の案内部３１ｅに連通し、第３の案内部３１ｅ側を長辺とする台形、換言すれば、くさび形状に形成されている。
図１３（ａ）、（ｂ）においては、第１、第２の案内部３１ｃ、３１ｄは図示を省略されているが、第１の案内部３１ｃ、第２の案内部３１ｄおよび第３の案内部３１ｅは同じ深さであり、また底面は平坦である。
図１３（ｂ）に図示されるように、第３の案内部３１ｅと保持部３２ｂとは同じ深さである。 The holding portion 32b communicates with the third guide portion 31e and is formed in a trapezoid shape having a long side on the third guide portion 31e side, in other words, a wedge shape.
In FIGS. 13A and 13B, the first and second guide portions 31c and 31d are not shown, but the first guide portion 31c, the second guide portion 31d, and the third guide are omitted. The portion 31e has the same depth, and the bottom surface is flat.
As illustrated in FIG. 13B, the third guide portion 31e and the holding portion 32b have the same depth.

実施形態３においては、実施形態１と同様に、係合方向は、軸芯１５の切欠き３０Ｂの幅方向である。
図１３（ａ）に図示されるように、第３の案内部３１ｅが保持部３２ｂに連通する面が境界面であり、その幅をＷ１とする。また、保持部３２ｂの台形の最大幅である長辺の長さをＷ２とした場合、負極集電部材２０の突起２３の幅ｘは、Ｗ２≧ｘ＞Ｗ１とされている。
このようにすると、実施形態３における軸芯１５の切欠き３０Ｂと負極集電部材２０の突起２３ａの係合関係は、実施形態１の軸芯１５の切欠き３０と負極集電部材２０の突起２３の場合と同様となる。
従って、実施形態３においても、実施形態１と同様の効果を奏する。 In the third embodiment, as in the first embodiment, the engagement direction is the width direction of the notch 30 B of the shaft core 15.
As illustrated in FIG. 13A, the surface where the third guide portion 31e communicates with the holding portion 32b is a boundary surface, and the width thereof is W1. Further, when the length of the long side which is the maximum width of the trapezoid of the holding portion 32b is W2, the width x of the protrusion 23 of the negative electrode current collecting member 20 is W2 ≧ x> W1.
In this way, the engagement relationship between the notch 30B of the shaft core 15 and the protrusion 23a of the negative electrode current collecting member 20 in the third embodiment is the same as that of the notch 30 of the shaft core 15 and the negative electrode current collecting member 20 of the first embodiment. This is the same as the case of 23.
Therefore, the third embodiment also has the same effect as the first embodiment.

実施形態３においては、図１３（ａ）に図示されるように、第３の案内部３１ｅが保持部３２ｂに連通する境界面における両側部は角部となっている。また、負極集電部材２０の突起２３ａは、矩形形状である。このため、負極集電部材２０の突起２３ａと軸芯１５の切欠き３０Ｂとの係合は、実施形態１および２の場合よりも外れ難い。すなわち、軸芯１５の負極集電部材２０からの変位をより確実に制限することができる。 In the third embodiment, as shown in FIG. 13A, both side portions of the boundary surface where the third guide portion 31e communicates with the holding portion 32b are corner portions. Further, the protrusion 23a of the negative electrode current collecting member 20 has a rectangular shape. For this reason, the engagement between the protrusion 23a of the negative electrode current collecting member 20 and the notch 30B of the shaft core 15 is less likely to be disengaged than in the first and second embodiments. That is, the displacement of the shaft core 15 from the negative electrode current collecting member 20 can be more reliably limited.

また、実施形態３においては、軸芯１５と負極集電部材２０との係合部が４箇所となっているので、これよりも係合部の数が少ない実施形態１および２の場合に比し、振動等の外力を分散する効果が大きく、負極集電部材２０による軸芯１５の保持力をより大きくすることができる。
なお、実施形態３において、実施形態１と同様な構成には、対応する構成に同じ符号を付し説明を省略する。 Further, in the third embodiment, since there are four engaging portions between the shaft core 15 and the negative electrode current collecting member 20, the number of engaging portions is smaller than that in the first and second embodiments. In addition, the effect of dispersing external force such as vibration is great, and the holding force of the shaft core 15 by the negative electrode current collecting member 20 can be further increased.
In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals and the description thereof is omitted.

（実施形態４）
図１４は、本発明の実施形態４に係る軸芯の切欠き形状を示す側面図である。また、図１５は、実施形態４に係る軸芯の切欠きの構造を示し、図１５（ａ）は、切欠きの長さ方向に沿う平面図、図１５（ｂ）は、図１５（ａ）のＡ−Ａ’に沿う断面図である。
実施形態４においては、図１４に図示されるように、軸芯１５の切欠き３０Ｃは、軸芯１５の軸方向に平行な第１の案内部３１ｆ、これに垂直な第２の案内部３１ｇおよび保持部３２ｃを有する。
図１５（ａ）、（ｂ）には、第１の案内部３１ｆは図示を省略されているが、第１の案内部３１ｆと第２の案内部３１ｇは同じ深さであり、また底面は平坦である。 (Embodiment 4)
FIG. 14 is a side view showing the notch shape of the shaft core according to the fourth embodiment of the present invention. 15 shows the structure of the shaft core notch according to the fourth embodiment, FIG. 15A is a plan view along the length direction of the notch, and FIG. 15B is FIG. It is sectional drawing in alignment with AA '.
In the fourth embodiment, as shown in FIG. 14, the notch 30C of the shaft core 15 includes a first guide portion 31f parallel to the axial direction of the shaft core 15, and a second guide portion 31g perpendicular to the first guide portion 31g. And a holding portion 32c.
15A and 15B, the first guide portion 31f is not shown, but the first guide portion 31f and the second guide portion 31g have the same depth, and the bottom surface is It is flat.

図１５（ａ）に図示されるように、第２の案内部３１ｇが保持部３２ｃに連通する面が境界面であり、その幅をＷ１とする。また、保持部３２ｃの最大幅（直径）をＷ２とした場合、負極集電部材２０の突起２３ｂの幅ｘは、Ｗ２≧ｘ＞Ｗ１とされている。
また、図１５（ｂ）に図示されるように、保持部３２ｃの深さは、第２の案内部３１ｇとの境界面よりも深く形成されている。境界面の深さをＤ１、保持部３２ｃの最大深さをＤ２、とした場合、負極集電部材２０における突起２３ｂの厚さ（ｙは、Ｄ２≧ｙ＞Ｄ１とされている。従って、係合用突出部の長さΔＤ＝（ｙ−Ｄ１）が、負極集電部材２０の突起２３と軸芯１５の保持部３２ａとが係合する長さとなる。負極集電部材２０の突起２３ｂは、図１５（ａ）、（ｂ）に二点鎖線で図示されているように、平面視では、円形形状を保持部３２ｃと第２の案内部３１ｇとの境界面で切断した形状とされている。 As shown in FIG. 15A, the surface where the second guide portion 31g communicates with the holding portion 32c is a boundary surface, and the width thereof is W1. Further, when the maximum width (diameter) of the holding portion 32c is W2, the width x of the protrusion 23b of the negative electrode current collecting member 20 is W2 ≧ x> W1.
Further, as shown in FIG. 15B, the depth of the holding portion 32c is formed deeper than the boundary surface with the second guide portion 31g. When the depth of the boundary surface is D1 and the maximum depth of the holding portion 32c is D2, the thickness of the protrusion 23b in the negative electrode current collecting member 20 (y is D2 ≧ y> D1. The length ΔD = (y−D1) of the combined protrusion is a length in which the protrusion 23 of the negative electrode current collector 20 and the holding part 32a of the shaft core 15 are engaged. As shown by the two-dot chain line in FIGS. 15A and 15B, in a plan view, the circular shape is cut at the boundary surface between the holding portion 32c and the second guide portion 31g. .

実施形態４においては、係合方向は、幅方向および深さ方向となっている。このように実施形態４では、軸芯１５の切欠き３０Ｃと負極集電部材２０の突起２３ｂは、幅方向および深さ方向の二方向において係合するので、両部材の係合を一層確実なものとすることができる。 In the fourth embodiment, the engagement direction is the width direction and the depth direction. As described above, in Embodiment 4, the notch 30C of the shaft core 15 and the protrusion 23b of the negative electrode current collecting member 20 are engaged in two directions, ie, the width direction and the depth direction. Can be.

（実施形態５）
図１６は、本発明の実施形態５に係る軸芯の切欠きの構造を示し、図１６（ａ）は、切欠きの長さ方向に沿う平面図、図１６（ｂ）は、図１６（ａ）のＡ−Ａ’に沿う断面図である。
実施形態５は、図１６（ｂ）に図示されるように、実施形態１として図示された図７（ｂ）と同様に、軸芯１５の切欠き３０Ｄにおける案内部３１ｈと保持部３２ｄの深さは同一である。
しかし、実施形態５では、図１６（ａ）に図示されるように、案内部３１ｈの幅が、保持部３２ｄの最大幅（直径）よりも大きい点で実施形態１と相違する。
実施形態５における、負極集電部材２０の突起２３は、実施形態１と同様に半球形状である。 (Embodiment 5)
16A and 16B show the structure of the shaft core notch according to the fifth embodiment of the present invention. FIG. 16A is a plan view along the length direction of the notch, and FIG. It is sectional drawing which follows AA 'of a).
In the fifth embodiment, as shown in FIG. 16B, the depth of the guide portion 31h and the holding portion 32d in the notch 30D of the shaft core 15 is the same as in FIG. Is the same.
However, the fifth embodiment differs from the first embodiment in that the width of the guide portion 31h is larger than the maximum width (diameter) of the holding portion 32d, as shown in FIG.
In the fifth embodiment, the protrusion 23 of the negative electrode current collecting member 20 has a hemispherical shape as in the first embodiment.

すなわち、実施形態５における係合方向は幅方向であり、境界面の幅をＷ１、保持部３２ｄの最大幅（直径）をＷ２、案内部３１ｈの幅をＷ３とした場合、負極集電部材２０の突起２３の幅（直径）ｘは、Ｗ３＞Ｗ２≧ｘ＞Ｗ１とされている。
実施形態５では、Ｗ２≧ｘ＞Ｗ１とされているので、実施形態１と同様な効果を奏する。
また、案内部３１ｈの幅Ｗ３が、負極集電部材２０の突起２３の幅（直径）ｘよりも大きいので、負極集電部材２０の突起２３を、境界面の位置に容易に配置することができる。 That is, when the engagement direction in the fifth embodiment is the width direction, the width of the boundary surface is W1, the maximum width (diameter) of the holding portion 32d is W2, and the width of the guide portion 31h is W3, the negative electrode current collecting member 20 The width (diameter) x of the projection 23 is W3> W2 ≧ x> W1.
In the fifth embodiment, since W2 ≧ x> W1, the same effects as in the first embodiment are obtained.
Further, since the width W3 of the guide portion 31h is larger than the width (diameter) x of the protrusion 23 of the negative electrode current collecting member 20, the protrusion 23 of the negative electrode current collecting member 20 can be easily disposed at the position of the boundary surface. it can.

（実施形態６）
図１７は、本発明の実施形態６に係る軸芯の切欠きの構造を示し、図１７（ａ）は、切欠きの長さ方向に沿う平面図、図１７（ｂ）は、図１７（ａ）のＡ−Ａ’に沿う断面図である。
実施形態６は、図１７（ａ）に図示されるように、実施形態２として図示された図１０（ａ）と同様に、軸芯１５の切欠き３０Ｅにおける案内部３１ｉと保持部３２ｅの幅は同一である。
しかし、実施形態６では、図１７（ｂ）に図示されるように、案内部３１ｉの深さＤ３が、保持部３２ｅの最大の深さＤ２よりも深い点で実施形態２と相違する。 (Embodiment 6)
17A and 17B show a structure of a shaft core notch according to Embodiment 6 of the present invention, FIG. 17A is a plan view along the length direction of the notch, and FIG. 17B is FIG. It is sectional drawing which follows AA 'of a).
In the sixth embodiment, as shown in FIG. 17A, the width of the guide portion 31 i and the holding portion 32 e in the notch 30 E of the shaft core 15 as in FIG. 10A illustrated as the second embodiment. Are the same.
However, the sixth embodiment differs from the second embodiment in that the depth D3 of the guide portion 31i is deeper than the maximum depth D2 of the holding portion 32e, as illustrated in FIG. 17B.

軸芯１５の切欠き３０Ｅの保持部３２ｅは、底面が平坦ではなく、球面状とされており、案内部３１ｉの底面は、この球面状の底面よりも深く形成されている。
また、負極集電部材２０の突起２３ｃは、二点鎖線で図示されるように、半球状に形成されている。 The holding portion 32e of the notch 30E of the shaft core 15 has a bottom surface that is not flat, but is spherical, and the bottom surface of the guide portion 31i is formed deeper than the spherical bottom surface.
Further, the protrusion 23c of the negative electrode current collecting member 20 is formed in a hemispherical shape as shown by a two-dot chain line.

実施形態６における係合方向は深さ方向であり、境界面の深さをＤ１、保持部３２ｅの最大深さをＤ２、案内部３１ｉの深さをＤ３とした場合、負極集電部材２０の突起２３ｃの厚さｙは、Ｄ３＞Ｄ２≧ｙ＞Ｄ１とされている。
実施形態６では、Ｄ２≧ｙ＞Ｄ１とされているので、実施形態２と同様な効果を奏する。
また、案内部３１ｉの深さＤ３が、負極集電部材２０の突起２３ｃの深さｙよりも深いので、負極集電部材２０の突起２３ｃを、境界面の位置に容易に配置することができる。 The engaging direction in the sixth embodiment is the depth direction, and when the depth of the boundary surface is D1, the maximum depth of the holding portion 32e is D2, and the depth of the guide portion 31i is D3, the negative electrode current collecting member 20 The thickness y of the protrusion 23c is D3> D2 ≧ y> D1.
In the sixth embodiment, since D2 ≧ y> D1, the same effects as in the second embodiment are obtained.
Further, since the depth D3 of the guide portion 31i is deeper than the depth y of the protrusion 23c of the negative electrode current collector member 20, the protrusion 23c of the negative electrode current collector member 20 can be easily disposed at the position of the boundary surface. .

（実施形態７）
図１８は、本発明の実施形態７に係る軸芯の切欠きの構造を示し、図１８（ａ）は、切欠きの長さ方向に沿う平面図、図１８（ｂ）は、図１８（ａ）のＡ−Ａ’に沿う断面図である。
実施形態７は、実施形態５および実施形態６を組み合わせたものである。つまり、実施形態７においては、軸芯１５の切欠き３０Ｆと負極集電部材２０の突起２３ｃの係合方向は幅方向および深さ方向であり、案内部３１ｊの幅および深さは、保持部３２ｆの最大の幅および最大の深さよりも大きい。 (Embodiment 7)
18A and 18B show a structure of a shaft core notch according to Embodiment 7 of the present invention, FIG. 18A is a plan view along the length direction of the notch, and FIG. 18B is FIG. It is sectional drawing which follows AA 'of a).
The seventh embodiment is a combination of the fifth and sixth embodiments. That is, in Embodiment 7, the engagement direction of the notch 30F of the shaft core 15 and the protrusion 23c of the negative electrode current collecting member 20 is the width direction and the depth direction, and the width and depth of the guide portion 31j are the holding portion. It is larger than the maximum width and the maximum depth of 32f.

軸芯１５の切欠き３０Ｆの保持部３２ｆは、底面が平坦ではなく、球面状とされており、案内部３１ｉは、この球面状の底面よりも深く、平坦な底面に形成されている。
また、負極集電部材２０の突起２３ｃは、実施形態６と同様に、半球形状に形成されている。 The holding portion 32f of the notch 30F of the shaft core 15 is not flat but has a spherical shape, and the guide portion 31i is deeper than the spherical bottom surface and is formed on a flat bottom surface.
Further, the protrusion 23c of the negative electrode current collecting member 20 is formed in a hemispherical shape as in the sixth embodiment.

図１８（ａ）に図示されるように、境界面の幅をＷ１、保持部３２ｆの最大幅（直径）をＷ２、案内部３１ｊの幅をＷ３とした場合、負極集電部材２０の突起２３の幅（直径）ｘは、Ｗ３＞Ｗ２≧ｘ＞Ｗ１とされている。
また、図１８（ｂ）に図示されるように、境界面の深さをＤ１、保持部３２ｆの最大深さをＤ２、案内部３１ｊの深さをＤ３とした場合、負極集電部材２０の突起２３ｃの厚さｙは、Ｄ３＞Ｄ２≧ｙ＞Ｄ１とされている。 As shown in FIG. 18A, when the width of the boundary surface is W1, the maximum width (diameter) of the holding portion 32f is W2, and the width of the guide portion 31j is W3, the protrusion 23 of the negative electrode current collecting member 20 Is set such that W3> W2 ≧ x> W1.
Further, as illustrated in FIG. 18B, when the depth of the boundary surface is D1, the maximum depth of the holding portion 32f is D2, and the depth of the guide portion 31j is D3, The thickness y of the protrusion 23c is D3> D2 ≧ y> D1.

実施形態７では、Ｗ２≧ｘ＞Ｗ１とされ、かつ、Ｄ２≧ｙ＞Ｄ１とされているので、実施形態４と同様な効果を奏する。また、案内部３１ｊの幅Ｗ３が、負極集電部材２０の突起２３ｃの幅（直径）ｘよりも大きく、かつ、案内部３１ｊの深さＤ３が、負極集電部材２０の突起２３ｃの深さｙよりも深いので、負極集電部材２０の突起２３ｃを、境界面の位置に容易に配置することができる。 In the seventh embodiment, since W2 ≧ x> W1 and D2 ≧ y> D1, the same effects as in the fourth embodiment are obtained. Further, the width W3 of the guide portion 31j is larger than the width (diameter) x of the protrusion 23c of the negative electrode current collector member 20, and the depth D3 of the guide portion 31j is the depth of the protrusion 23c of the negative electrode current collector member 20. Since it is deeper than y, the protrusion 23c of the negative electrode current collecting member 20 can be easily disposed at the position of the boundary surface.

以上説明した通り、本発明の各実施形態では、軸芯１５における切欠き３０、３０Ａ〜３０Ｆの保持部３２、３２ａ〜３２ｆに、案内部３１、３１ｂ、３１ｅ、３１ｇ〜３１ｊとの境界面から係合方向に突き出す係合凹部を設けた。また、負極集電部材２０の突起２３、２３ａ〜２３ｃには、境界面よりも保持部の係合凹部側に突き出す係合用突出部を設けた。
このため、保持部３２、３２ａ〜３２ｆの係合凹部と突起２３、２３ａ〜２３ｃの係合用突出部とが係合し、軸芯１５が負極集電部材２０に対して変位するのを確実に抑えることができる。 As described above, in each embodiment of the present invention, the holding portions 32 and 32a to 32f of the notches 30 and 30A to 30F in the shaft core 15 are connected to the guide portions 31, 31b, 31e, and 31g to 31j. An engagement recess protruding in the engagement direction was provided. Further, the protrusions 23, 23a to 23c of the negative electrode current collecting member 20 were provided with engaging protrusions protruding toward the engaging concave portion of the holding portion from the boundary surface.
For this reason, the engaging recesses of the holding portions 32 and 32a to 32f are engaged with the engaging protrusions of the protrusions 23 and 23a to 23c, and the shaft core 15 is reliably displaced with respect to the negative electrode current collecting member 20. Can be suppressed.

しかも、係合方向における係合用突出部の長さが係合凹部の長さ以下とされているので、突起２３、２３ａ〜２３ｃが保持部３２、３２ａ〜３２ｆに係合している状態で、案内部３１、３１ｂ、３１ｅ、３１ｇ〜３１ｊは、元の状態に復元しており、拡大する方向に変形されていない。従って、突起２３、２３ａ〜２３ｃの係合用突出部の長さは、常に、実際に係合している長さとして確保することができる。 Moreover, since the length of the engaging protrusion in the engaging direction is equal to or less than the length of the engaging recess, the protrusions 23 and 23a to 23c are engaged with the holding portions 32 and 32a to 32f. The guide portions 31, 31b, 31e, 31g to 31j are restored to their original states and are not deformed in the expanding direction. Therefore, the lengths of the protrusions for engagement of the protrusions 23 and 23a to 23c can always be ensured as actually engaged lengths.

なお、上記各実施形態においては、軸芯１５に形成する切欠き３０、３０Ａ〜３０Ｆを軸芯１５の厚さの中間に底面が形成された溝として例示した。しかし、切欠き３０、３０Ａ〜３０Ｆを、軸芯１５を厚さ方向に貫通する開口またはスリットとしてもよい。この場合、溝幅の中央部分のみを開口またはスリットにすることもできる。 In each of the above embodiments, the notches 30, 30A to 30F formed in the shaft core 15 are illustrated as grooves having a bottom surface in the middle of the thickness of the shaft core 15. However, the notches 30, 30A to 30F may be openings or slits that penetrate the shaft core 15 in the thickness direction. In this case, only the central part of the groove width can be an opening or a slit.

上記実施形態１〜７に示した構造を部分的に組み合わせることができる。その一例を具体的に例示すれば、軸芯１５の切欠き３０、３０Ａ〜３０Ｆおよび負極集電部材２０の突起２３、２３ａ〜２３ｃの数、軸芯１５の案内部３１、３１ａ〜３１ｊ、保持部３２、３２ａ〜３２ｆおよび突起２３、２３ａ〜２３ｃの形状、構造は、適宜、組み合わせることができる。また、案内部３１、３１ａ〜３１ｊの形状は、各実施形態に示す以外の形状と
したり、適宜、傾斜部を設けたり、角部を円弧状としたりすることができる。 The structures shown in the first to seventh embodiments can be partially combined. To give a specific example, the notches 30, 30A to 30F of the shaft core 15 and the number of projections 23, 23a to 23c of the negative electrode current collecting member 20, the guide portions 31, 31a to 31j of the shaft core 15, and the holding The shapes and structures of the portions 32 and 32a to 32f and the protrusions 23 and 23a to 23c can be appropriately combined. Moreover, the shape of the guide parts 31 and 31a-31j can be made into shapes other than what is shown in each embodiment, an inclined part can be provided suitably, and a corner | angular part can be made into circular arc shape.

負極集電部材２０の突起２３、２３ａ〜２３ｃの形状を、各実施形態に示した半球状または直方体状以外の形状としてもよい。 The shape of the protrusions 23 and 23a to 23c of the negative electrode current collecting member 20 may be a shape other than the hemispherical shape or the rectangular parallelepiped shape shown in each embodiment.

上記実施形態では、負極集電部材２０に負極導電リード４７を接合し、負極導電リード４７を電池缶２の缶底２ｃに接合した構造として例示した。しかし、負極集電部材２０を、例えば、銅にニッケルが拡散融合されたクラッド材としたり、銅にニッケルめっき層を設けたり、あるいは、銅合金としたりして、直接、電池缶２の缶底２ｃに接合するようにしてもよい。 In the embodiment described above, the negative electrode conductive lead 47 is bonded to the negative electrode current collecting member 20, and the negative electrode conductive lead 47 is illustrated as a structure bonded to the can bottom 2 c of the battery can 2. However, the negative electrode current collecting member 20 is made of, for example, a clad material in which nickel is diffused and fused with copper, a nickel plating layer is provided on copper, or a copper alloy is used. You may make it join to 2c.

上記実施形態では、電池缶２に負極集電部材２０を接合する構造として例示した。しかし、電池缶２に正極集電部材２７を接合する円筒形二次電池１に対して適用することが可能である。 In the said embodiment, it illustrated as a structure which joins the negative electrode current collection member 20 to the battery can 2. FIG. However, it can be applied to the cylindrical secondary battery 1 in which the positive electrode current collecting member 27 is joined to the battery can 2.

上記各実施形態では、リチウムイオン円筒形二次電池の場合で説明した。しかし、本発明は、ニッケル水素電池またはニッケル・カドミウム電池、鉛蓄電池のように水溶性電解液を用いる円筒形二次電池にも適用が可能である。 In each of the above embodiments, the case of a lithium ion cylindrical secondary battery has been described. However, the present invention can also be applied to a cylindrical secondary battery using a water-soluble electrolyte such as a nickel metal hydride battery, a nickel cadmium battery, or a lead storage battery.

本発明の円筒形二次電池は、上記各実施形態に限られるものではなく、本発明の趣旨の範囲内において、適宜、変形して適用することが可能である。要は、軸芯に設けた切欠きにおける保持部に、案内部との境界面から係合方向に突き出す係合凹部を設け、集電部材の突起に境界面よりも保持部の係合凹部側に突き出す係合用突出部を設け、かつ、係合方向における係合用突出部の長さを係合凹部の長さ以下としたものであればよい。 The cylindrical secondary battery of the present invention is not limited to the above embodiments, and can be appropriately modified and applied within the scope of the gist of the present invention. The point is that the holding portion in the notch provided in the shaft core is provided with an engaging recess protruding in the engaging direction from the boundary surface with the guide portion, and the protrusion of the current collecting member is closer to the engaging recess of the holding portion than the boundary surface It is only necessary that the protrusion for engagement protrudes from the protrusion and the length of the protrusion for engagement in the engagement direction is equal to or less than the length of the engagement recess.

１円筒形二次電池
２電池缶
３電池蓋
１０電極群
１１正極電極
１２負極電極
１５軸芯
２０負極集電部材
２３、２３ａ〜２３ｃ突起
３０、３０Ａ〜３０Ｆ切欠き
３１、３１ａ〜３１ｊ案内部
３２、３２ａ〜３２ｆ保持部

DESCRIPTION OF SYMBOLS 1 Cylindrical secondary battery 2 Battery can 3 Battery cover 10 Electrode group 11 Positive electrode 12 Negative electrode 15 Axle core 20 Negative electrode current collection member 23, 23a-23c Protrusion 30, 30A-30F Notch 31, 31a-31j Guide part 32 , 32a to 32f holding part

Claims

An electrode group in which a positive electrode and a negative electrode are wound around a cylindrical shaft core via a separator;
A battery can in which the electrode group is housed and an electrolyte is injected;
A battery lid disposed on one end of the battery can to seal the battery can;
One of the positive electrode and the negative electrode is connected, and a ring-shaped current collecting member fixed to the bottom of the battery can,
The current collecting member has a plurality of protrusions;
The shaft core has a notch that engages with each projection of the current collecting member,
Each of the notches has a guide portion that opens to a tip surface of the shaft core, and a holding portion that communicates with the guide portion,
The holding portion has an engagement recess protruding in an engagement direction from a boundary surface communicating with the guide portion,
Each of the protrusions of the current collecting member protrudes toward the engaging recess of the holding portion from the boundary surface, and an engaging protrusion having a length in the engaging direction equal to or less than the length of the engaging recess. A cylindrical secondary battery comprising:

2. The cylindrical secondary battery according to claim 1, wherein the engagement direction is a width direction of the protrusion and the notch, and a maximum width of the protrusion is larger than a width at the boundary surface and the holding is performed. A cylindrical secondary battery having a width equal to or less than the width of the portion.

3. The cylindrical secondary battery according to claim 1, wherein the engagement direction is a depth direction of the protrusion and the notch, and an engagement tip portion of the protrusion is formed by the guide portion on the boundary surface. A cylindrical secondary battery characterized in that it is located deeper than the bottom surface and below the bottom surface of the holding portion.

In the cylindrical secondary battery according to any one of claims 1 to 3, wherein the notch the guide section, that has a direction which is formed in the portion which is inclined relative to the axial direction of said axis A featured cylindrical secondary battery.

5. The cylindrical secondary battery according to claim 1, wherein the guide portion of the notch has a tapered portion that becomes wider toward a tip surface side of the shaft core. 6. Cylindrical secondary battery.

The cylindrical secondary battery according to any one of claims 1 to 5, wherein the guide portion of the notch has a portion perpendicular to the axial direction of the axial core. .

The cylindrical secondary battery according to any one of claims 1 to 6, wherein the guide portion of the shaft core has a portion from a tip surface of the shaft core to a boundary surface with the holding portion. A cylindrical secondary battery characterized by being wider than the maximum width of the protrusion.

The cylindrical secondary battery according to any one of claims 1 to 7, wherein the guide portion of the shaft core has a portion from a tip surface of the shaft core to a boundary surface with the holding portion. A cylindrical secondary battery, wherein the cylindrical secondary battery is formed deeper than a maximum depth of the holding portion.

9. The cylindrical secondary battery according to claim 1, wherein a planar shape of the guide portion is a circle or an ellipse. 10.

9. The cylindrical secondary battery according to claim 1, wherein the holding portion has a planar shape and a trapezoidal shape having a long side on a boundary surface side with the guide portion. Type secondary battery.

The cylindrical secondary battery according to any one of claims 1 to 10, wherein the holding portion has a spherical bottom surface.

The cylindrical secondary battery according to any one of claims 1 to 11, wherein the shaft core has three or more cutouts, and the protrusions of the current collecting member correspond to the cutouts. The cylindrical secondary battery is characterized in that the same number is formed.