JPH01220370A - Manufacture of electrode - Google Patents
Manufacture of electrodeInfo
- Publication number
- JPH01220370A JPH01220370A JP63044436A JP4443688A JPH01220370A JP H01220370 A JPH01220370 A JP H01220370A JP 63044436 A JP63044436 A JP 63044436A JP 4443688 A JP4443688 A JP 4443688A JP H01220370 A JPH01220370 A JP H01220370A
- Authority
- JP
- Japan
- Prior art keywords
- active material
- fitting section
- terminal
- substrate
- core body
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000004519 manufacturing process Methods 0.000 title claims description 13
- 239000011149 active material Substances 0.000 claims abstract description 31
- 239000002184 metal Substances 0.000 claims abstract description 26
- 229910052751 metal Inorganic materials 0.000 claims abstract description 26
- 229920005989 resin Polymers 0.000 claims abstract description 11
- 239000011347 resin Substances 0.000 claims abstract description 11
- 238000000034 method Methods 0.000 claims description 14
- 239000000835 fiber Substances 0.000 abstract description 14
- 239000000758 substrate Substances 0.000 abstract description 12
- 230000000694 effects Effects 0.000 abstract description 10
- 239000012188 paraffin wax Substances 0.000 abstract description 9
- BFDHFSHZJLFAMC-UHFFFAOYSA-L nickel(ii) hydroxide Chemical compound [OH-].[OH-].[Ni+2] BFDHFSHZJLFAMC-UHFFFAOYSA-L 0.000 abstract description 2
- 235000011837 pasties Nutrition 0.000 abstract 2
- 239000011162 core material Substances 0.000 description 29
- 238000010438 heat treatment Methods 0.000 description 5
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 3
- 239000002390 adhesive tape Substances 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 238000001035 drying Methods 0.000 description 3
- 238000003466 welding Methods 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- PLLZRTNVEXYBNA-UHFFFAOYSA-L cadmium hydroxide Chemical group [OH-].[OH-].[Cd+2] PLLZRTNVEXYBNA-UHFFFAOYSA-L 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 150000002815 nickel Chemical class 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000005245 sintering Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 229920003002 synthetic resin Polymers 0.000 description 1
- 239000000057 synthetic resin Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/24—Electrodes for alkaline accumulators
- H01M4/26—Processes of manufacture
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/50—Current conducting connections for cells or batteries
- H01M50/531—Electrode connections inside a battery casing
- H01M50/536—Electrode connections inside a battery casing characterised by the method of fixing the leads to the electrodes, e.g. by welding
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
- H01M50/50—Current conducting connections for cells or batteries
- H01M50/531—Electrode connections inside a battery casing
- H01M50/534—Electrode connections inside a battery casing characterised by the material of the leads or tabs
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Connection Of Batteries Or Terminals (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の目的〕
（産業上の利用分野）
本発明は電極の製造方法に係わり、特に、導電芯体の端
子取付部に金属端子を取付ける方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method of manufacturing an electrode, and particularly to a method of attaching a metal terminal to a terminal attaching portion of a conductive core.
（従来の技術）
従来のアルカリ電池用の導電芯体に端子を取付ける方法
として、特公昭５７−１８６３号公報に示される様に、
多孔性芯金に金属粉を焼結して得られた多孔性焼結基板
に活物質を含浸させて極板とし、この極板のリード取付
部に超音波振動を加えて多孔性芯金を露出させ、このリ
ード取付部に金属リードを超音波溶接または電気抵抗溶
接により固定する方法が知られている。また、他の方法
として、特公昭６０−４０１４５号公報に示される様に
、多孔性金属芯材にペースト状活物質を塗着した極板か
ら回転自在な円盤状切刃により活物質を除去した後にブ
ラッシングして芯材露出部を形成し、ここに端子を取付
ける方法が知られている。しかしながら。(Prior art) As a method of attaching a terminal to a conductive core for a conventional alkaline battery, as shown in Japanese Patent Publication No. 1863/1983,
A porous sintered substrate obtained by sintering metal powder onto a porous core metal is impregnated with an active material to form an electrode plate, and ultrasonic vibration is applied to the lead attachment part of this electrode plate to create a porous core metal. A method is known in which a metal lead is exposed and fixed to the lead attachment part by ultrasonic welding or electric resistance welding. In addition, as another method, as shown in Japanese Patent Publication No. 60-40145, the active material was removed from an electrode plate in which a paste-like active material was applied to a porous metal core material using a rotatable disc-shaped cutting blade. A method is known in which the core material is later brushed to form an exposed portion of the core material and a terminal is attached thereto. however.
これらの方法はいずれも導電芯体が多孔性芯金である場
合に適用できる方法であって、三次元的に連続した空間
を有するスポンジ状の金属多孔体や金属繊維を焼結した
多孔体を芯体とする場合には適用できない不都合がある
。即ち、これらの場合は、超音波振動や円盤状切刃では
充填された活物質がスポンジ状多孔体または繊維焼結体
と共に除去されてしまう、これはスポンジ状多孔体また
は繊維焼結体の強度が多孔性芯金に比べて弱すぎること
、および金属繊維が極板中に三次元的にマトリックスを
形成していることによる・
そこで、この様な三次元的に連続した空間を有する多孔
体にも適応できる方法として、特公昭５７−６２５号公
報に示される様に、多孔質焼結ニッケル基板の端子取付
部の両面を耐熱性の合成樹脂製の粘着テープで被覆し、
この粘着テープの上から端子取付部をプレスした後、こ
のニッケル基板に活物質を塗布し、この粘着テープを剥
がして端子取付部に活物質の存在しない露出部を形成し
、ここに端子をスポット溶接して極板を製造する方法が
知られている。しかしながら、この方法は生産性が悪く
址産に適さない欠点がある。また、他の方法として、特
開昭６２−２５２０６９号公報に示される様に、金属繊
維の焼結体よりなる導電芯体に活物質を充填し、これを
所定寸法に裁断して単位極板を得た後、この極板の端面
をローレットしたローラ間を通過させることにより、活
物質を除去して金属繊維の焼結部を露出させてリード取
付部を形成する方法が知られている。しかしこの方法で
は、金属繊維と共に活物質を押しつぶしてしまい、活物
質を完全に除去することができず、その後の端子取付け
に際し支障をきたし良好な集電効果を得ることができな
い、また、単位極板として切離して加工するため斌産化
に適さない面がある。All of these methods can be applied when the conductive core is a porous metal core, and can be applied to a sponge-like porous metal body with a three-dimensionally continuous space or a porous body made of sintered metal fibers. There is a disadvantage that it cannot be applied to a core body. That is, in these cases, the filled active material is removed together with the sponge-like porous body or the fiber sintered body by ultrasonic vibration or the disc-shaped cutting blade. This is because the metal fibers are too weak compared to the porous core metal, and the metal fibers form a three-dimensional matrix within the electrode plate. As shown in Japanese Patent Publication No. 57-625, a method that can also be applied is to cover both sides of the terminal attachment part of a porous sintered nickel board with adhesive tape made of heat-resistant synthetic resin.
After pressing the terminal mounting part on top of this adhesive tape, apply an active material to this nickel substrate, peel off this adhesive tape to form an exposed part without active material on the terminal mounting part, and spot the terminal here. A method of manufacturing electrode plates by welding is known. However, this method has the disadvantage of poor productivity and is not suitable for still production. In addition, as another method, as shown in Japanese Unexamined Patent Publication No. 62-252069, a conductive core made of a sintered body of metal fibers is filled with an active material, and this is cut into a predetermined size to form a unit electrode plate. There is a known method in which the active material is removed by passing the end face of the electrode plate between knurled rollers to expose the sintered part of the metal fibers, thereby forming the lead attachment part. However, with this method, the active material is crushed together with the metal fibers, and the active material cannot be completely removed, which causes problems when attaching the terminal afterwards, making it impossible to obtain a good current collection effect. Since it is processed by cutting it into plates, it is not suitable for mass production.
（発明が解決しようとする課題）
前述した様に、これまでの方法では導電芯体の端子取付
部に充填された活物質を取除く際に、導電芯体を損傷す
ることなく活物質を完全に除去することができず、その
ため良好な集電効果を得ることができる電池用電極を製
造することができなかった。(Problems to be Solved by the Invention) As mentioned above, in the conventional methods, when removing the active material filled in the terminal attachment part of the conductive core, it is difficult to completely remove the active material without damaging the conductive core. Therefore, it has been impossible to produce a battery electrode that can obtain a good current collecting effect.
本発明の目的は導電芯体を損傷することなく端子取付部
を露出することができ、リード端子を極板の端子取付部
に固定でき、良好な集電効果を得ることができる電池用
電極の製造方法を提供することにある。An object of the present invention is to provide a battery electrode that can expose the terminal mounting part without damaging the conductive core, fix the lead terminal to the terminal mounting part of the electrode plate, and obtain a good current collecting effect. The purpose is to provide a manufacturing method.
（課題を解決するための手段および作用）本発明は、導
電芯体の端部に位置する端子取付部を樹脂で被覆し、導
電芯体全体にペースト状活物質を充填した後、この導電
芯体を加熱することにより樹脂を除去して端子取付部を
露出させ、この端子取付部に金属端子を固定することを
特徴とする電極の製造方法である。(Means and effects for solving the problems) The present invention covers the terminal mounting portion located at the end of the conductive core with a resin, fills the entire conductive core with a paste-like active material, and then coats the conductive core with a paste-like active material. This method of manufacturing an electrode is characterized in that the resin is removed by heating the body to expose a terminal attachment portion, and a metal terminal is fixed to the terminal attachment portion.
本発明は導電芯体にペースト状の活物質を充填する前に
予め端子取付部を樹脂で被覆し、導電芯体に活物質を充
填した後にこの樹脂を加熱により除去することにより、
端子取付部に活物質が充填されることがないので、導電
芯体を損傷することなく端子取付部を露出させることが
でき、しかも活物質が端子取付部に残存することがない
ので。In the present invention, the terminal mounting portion is coated with resin before filling the conductive core with a paste-like active material, and the resin is removed by heating after the conductive core is filled with the active material.
Since the terminal attachment part is not filled with active material, the terminal attachment part can be exposed without damaging the conductive core, and the active material does not remain in the terminal attachment part.
良好な集電効果を得ることができる電池用電極を製造す
ることができる。さらに、端子取付部の樹脂は導電芯体
に充填されたペースト状の活物質中の水分を除去する加
熱乾燥工程で除去することができるので、従来の方法に
おける端子取付部を露出させる特別な工程を必要とせず
、景産上特筆すべき効果がある。A battery electrode that can obtain a good current collecting effect can be manufactured. Furthermore, the resin in the terminal attachment area can be removed by a heating drying process that removes moisture from the paste-like active material filled in the conductive core, which eliminates the special process of exposing the terminal attachment area in conventional methods. There is no need for this, and it has a noteworthy effect on the economy.
本発明に用いられる樹脂は常温で固体状のもので、加熱
することにより溶融するものが適当である。特に、ペー
スト状活物質の加熱乾燥の温度との関連から、約８０℃
から約１５０℃に加熱することにより、溶融し除去でき
るものが適当である。この観点から、溶融が４５℃から
６５℃のパラフィン等が最適である。The resin used in the present invention is suitably solid at room temperature and melts when heated. In particular, in relation to the heating drying temperature of the paste active material, approximately 80°C
A suitable material is one that can be melted and removed by heating to about 150°C. From this point of view, paraffin or the like having a melting temperature of 45°C to 65°C is optimal.
本発明は金属繊維の焼結体よりなる導電芯体のみならず
、スポンジ状多孔体よりなる導電芯体にも適応できる。The present invention can be applied not only to a conductive core made of a sintered body of metal fibers, but also to a conductive core made of a sponge-like porous body.
（実施例）
以下、本発明の実施例について図面を参照して説明する
０図面（ａ）、（ｂ）、（Ｃ）、（ｄ）は本発明に基づ
く電極の製造工程を示すフローチャートである。(Example) Examples of the present invention will be described below with reference to the drawings. Drawings (a), (b), (C), and (d) are flowcharts showing the manufacturing process of an electrode based on the present invention. .
まず、厚み約１．５ｍｍで多孔度約９５％の長尺で導電
芯体を構成する金属繊維焼結基板（１）を用意し、この
基板（１）の側端部に位置する幅約３■■の帯状の端子
取付部（２）に溶融したパラフィン（３）を塗布する。First, a long metal fiber sintered substrate (1) having a thickness of about 1.5 mm and a porosity of about 95% and constituting a conductive core is prepared. Apply melted paraffin (3) to the strip-shaped terminal attachment part (2) marked ■■.
これにより、端子取付部（２）をパラフィン（３）で被
覆し、無孔状態にした（図ａ）。As a result, the terminal attachment part (2) was coated with paraffin (3), making it non-porous (Figure a).
次に、この金属繊維焼結基板（１）に、水酸化ニッケル
を主成分とするペースト状活物質（４）を充填する。こ
の時、導電芯体（１）の端子取付部（２）にはパラフィ
ンが塗布されているのでペースト状の活物質は端子取付
部（２）を除いた金属繊維焼結基板（１）に充填される
（図ｂ）。Next, this metal fiber sintered substrate (1) is filled with a paste-like active material (4) whose main component is nickel hydroxide. At this time, paraffin is applied to the terminal attachment part (2) of the conductive core (1), so the paste-like active material is filled into the metal fiber sintered substrate (1) excluding the terminal attachment part (2). (Figure b).
その後、この金属繊維焼結基板（１）を温度１２０℃で
１０分間加熱乾燥して、ペースト状活物質（４）中の水
分を除去すると共に、端子取付部（２）上のパラフィン
（３）を溶融して除去した。Thereafter, this metal fiber sintered substrate (1) is heated and dried at a temperature of 120°C for 10 minutes to remove moisture in the paste active material (4) and remove the paraffin (3) on the terminal attachment part (2). was melted and removed.
次に、この基板（１）をローラー圧延して厚さ０．５ｍ
ｍの長尺の極板（５）とし、端子取付部（２）にリード
端子（６）をスポット溶接した（図ｃ）。Next, this substrate (1) was rolled to a thickness of 0.5 m.
A long electrode plate (5) with a length of m long was used, and a lead terminal (6) was spot welded to the terminal attachment part (2) (Figure c).
この極板（５）を所定寸法に裁断して電極（７）とした
（図ｄ）。This electrode plate (5) was cut into a predetermined size to form an electrode (7) (Figure d).
この様に電極を製造することにより、導電芯体から活物
質を除去する工程を省略することができ。By manufacturing the electrode in this manner, the step of removing the active material from the conductive core can be omitted.
端子取付部を被覆する樹脂は従来行われていた活物質の
乾燥工程において溶融除去されるので、特別な工程を設
けることなく、大幅な時間の短縮と製造コストの低減が
期待できる。さらに、端子取付部に活物質が残存するこ
とがないので、リード端子の取付けが強固となり、集電
効果が良好な電極を製造することができる。Since the resin covering the terminal attachment part is melted and removed during the conventional active material drying process, a significant reduction in time and manufacturing costs can be expected without the need for any special process. Furthermore, since no active material remains in the terminal attachment portion, the lead terminal can be firmly attached, and an electrode with good current collection effect can be manufactured.
上記の実施例では、電池の正極板につき説明したが１本
発明は、水酸化カドミウムを主成分とする負極板につい
ても同様に適応できる。Although the above embodiments have been described with respect to the positive electrode plate of a battery, the present invention can be similarly applied to a negative electrode plate whose main component is cadmium hydroxide.
以上の様に１本発明によれば、導電芯体を損傷すること
なく、容易にしかも確実に導電芯体の端子取付部を露出
することができ、集電効果の良好な電極を製造すること
ができる。As described above, according to the present invention, it is possible to easily and reliably expose the terminal attachment portion of the conductive core without damaging the conductive core, and to manufacture an electrode with good current collecting effect. Can be done.
図（ａ） 、 （ｂ） 、 （ｃ） 、 （ｄ）は本発
明の詳細な説明するための電極の製造工程を示すフロー
チャートである。
１・・・金属繊維焼結基板 ２・・・端子取付部３
・・・パラフィン ４・・・ペースト状活
物質５・・・極板 ６・・・リード端
子７・・・電極Figures (a), (b), (c), and (d) are flowcharts showing the electrode manufacturing process for detailed explanation of the present invention. 1... Metal fiber sintered substrate 2... Terminal mounting part 3
... Paraffin 4 ... Paste active material 5 ... Electrode plate 6 ... Lead terminal 7 ... Electrode
Claims (1)
ースト状活物質を充填した後、この導電芯体を加熱する
ことにより端子取付部の樹脂を除去して端子取付部を露
出させ、この端子取付部に金属端子を固定することを特
徴とする電極の製造方法。After covering the terminal attachment part of the conductive core with resin and filling the conductive core with a paste active material, the conductive core is heated to remove the resin from the terminal attachment part and expose the terminal attachment part. , a method for manufacturing an electrode, characterized in that a metal terminal is fixed to the terminal mounting portion.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63044436A JPH01220370A (en) | 1988-02-29 | 1988-02-29 | Manufacture of electrode |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63044436A JPH01220370A (en) | 1988-02-29 | 1988-02-29 | Manufacture of electrode |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01220370A true JPH01220370A (en) | 1989-09-04 |
Family
ID=12691441
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63044436A Pending JPH01220370A (en) | 1988-02-29 | 1988-02-29 | Manufacture of electrode |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01220370A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20000014999A (en) * | 1998-08-26 | 2000-03-15 | 손욱 | Cylindrical secondary electric cell |
| WO2014002783A1 (en) * | 2012-06-25 | 2014-01-03 | Ｊｅインターナショナル株式会社 | Application device, removal device, application and removal system as well as application method, removal method, and application and removal method |
| KR20200084461A (en) * | 2018-12-27 | 2020-07-13 | 한밭대학교 산학협력단 | Apparatus for manufacturing electronic complexity using 3D printed and method therefor |
-
1988
- 1988-02-29 JP JP63044436A patent/JPH01220370A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20000014999A (en) * | 1998-08-26 | 2000-03-15 | 손욱 | Cylindrical secondary electric cell |
| WO2014002783A1 (en) * | 2012-06-25 | 2014-01-03 | Ｊｅインターナショナル株式会社 | Application device, removal device, application and removal system as well as application method, removal method, and application and removal method |
| KR20200084461A (en) * | 2018-12-27 | 2020-07-13 | 한밭대학교 산학협력단 | Apparatus for manufacturing electronic complexity using 3D printed and method therefor |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US2861115A (en) | Battery plate and tab assembly | |
| CA2051826C (en) | Electrode having a conductive contact area and method of making the same | |
| JPH03119651A (en) | Method of manufacturing electrode with porous support for electrochemical cell and electrode obtained by the method | |
| JPH01220370A (en) | Manufacture of electrode | |
| US4106184A (en) | Method for making fused solid electrolyte capacitor assemblages and a fused capacitor made thereby | |
| EP0464397B1 (en) | Method for securing a current collector to an electrode comprising a metallic spongeous supporting structure | |
| JPS5855620B2 (en) | Chikudenchiyoudenkiyokuno Seizouhouhou | |
| JP2926235B2 (en) | Method for producing electrode for alkaline battery | |
| JPS62219462A (en) | Manufacture of electrode plate for alkaline storage battery | |
| JPH02197054A (en) | Manufacture of electrode for alkaline battery | |
| JPH02250261A (en) | Manufacture of paste type electrode for alkaline storage battery | |
| US3767465A (en) | Electro-chemical cells | |
| JP2687510B2 (en) | Manufacturing method of chip-shaped solid electrolytic capacitor | |
| JPS59111261A (en) | Manufacture of plate for alkaline storage battery | |
| JP2749648B2 (en) | Method for manufacturing sodium-sulfur battery | |
| JPS62237665A (en) | Manufacture of plate for alkaline storage battery | |
| JPH0138881Y2 (en) | ||
| JPH01265452A (en) | Manufacture of paste type electrode | |
| JPH0713176Y2 (en) | Electrode plate for alkaline batteries | |
| JPH05243100A (en) | Manufacture of solid-state electrolytic capacitor | |
| JPS58115757A (en) | Manufacture of electrode plate group for lead storage battery | |
| JPS59105264A (en) | Manufacture of alkaline storage battery plate | |
| JPS63193465A (en) | Cylindrical nonaqueous electrolyte battery | |
| JPS5880269A (en) | Manufacture of electrode for battery | |
| WO2025112116A1 (en) | Electrode sheet having central tab and preparation method therefor, and battery |