1234307 玫、發明說明 【發明所屬之技術領域】 本發明是有關於一種方形電池之端蓋板結構，且特別是 有關於一種方形鋰離子電池之端蓋板結構。 【先前技術】 隨著可攜式電子產品朝輕、薄、短、小發展，以及對可 攜式電子產品一次充電可用時間增長的要求，小型、輕量化 和具高能量密度的二次電池乃成為可攜式電子產品不可或 缺的零組件之一。 在二次電池中，由於鋰離子電池具有高工作電壓、能量 密度大、重量輕、以及壽命長等優點，且能滿足可攜式電子 產品輕小的需求。因此，鋰離子電池目前已廣泛地應用於可 攜式電子產品中，例如筆記型電腦（Noteb〇〇k)、個人數位助 理（P⑽刪1 Digital Assistant ; PDA)、以及行動電話（M〇bile Phone)等 ° 目刖，鐘離子電池之端蓋板的安全設計主要為安全閥設 計以及端蓋板下設置導電片。安全閥設計係針對電池内壓力 不正㊉升同時，利用開閥方式進行洩壓，以避免電池爆炸。 然而，安全閥設計對於電池形變則無保護能力。另外，於端 蓋板下設置導電片之設計係針對電池於側向豎立魔扁，即γ 方向壓扁(Υ Crush)時，讓導電片先行與電池之罐體接觸製 造外部短路，以避免電池内部因過熱而爆炸。 1234307 【發明内容】 因此，本發明之目的就是在提供一種方形電池之端蓋板 結構，僅需改變端蓋板之結構設計，即可在電池產生側向形 變時’產生外部短路’而可不需另外在端蓋板下設置導電 片。故，可簡化製程。 本發明之另一目的就是在提供一種方形電池之端蓋板 結構，以鉚釘頭作為區隔，端蓋板之一側的平面結構之厚度 較另一側之厚度薄。如此一來，端蓋板厚度較薄之平面的結 構強度將比另一側較厚之平面來的脆弱。當方形電池遭受γ 方向壓扁時’鈿蓋板厚度較薄之平面會先產生形變而凸起彎 曲，此凸起之端蓋板平面與鉚釘頭接觸，進而在方形電池形 變時造成外部短路之路徑。故，可提升電池在使用上的安全 性。 本發明之再一目的是在提供一種方形電池之端蓋板結 構，端蓋板之背面至少包括貫穿端蓋板短轴之V型溝槽。 由於端蓋板具有V型溝槽處的結構強度較弱，因此當方形 電池遭受Υ方向壓扁時，V型溝槽處會先產生形變而使端 蓋板面凸起而與鉚釘頭接觸，進而造成外部短路之路徑。如 此一來，可降低電池形變的危險性。 本發明之又一目的是在提供一種方形電池之端蓋板結 構’柳釘頭之短侧壁與方形平板之平面區之間具有無隔絕物 的間隙，因此在端蓋板凸起形變時，可有效提升方形平板與 鉚釘頭之接觸機率。 根據本發明之上述目的，提出一種方形電池之端蓋板結 1234307 構’至少包括：一方形平板具有相對之一第一表面以及一第 表面v、中第一表面為一平面；以及一鉚釘頭位於上述之 方形平板之第一表面上’而將方形平板之第一表面區隔成— =-平面區以及一第二平面區，其中第一平面區之高度低於 第一平面區之高度，且第一平面區與第二平面區鄰近於上述 之鉚釘頭。 依照本發明一較佳實施例，上述之方形平板更至少包括 V型溝槽位於方形平板之第二表面上並貫穿第二表= 轴0 由於鉚釘頭兩侧之第一平面區與第二平面區之厚度不 同’而使得第一平面區之結構較為脆弱，再加上方形平板之 第-表面具有貫穿第二表面短軸4 v型溝槽。因此，方形 平板可在方形電池受到γ方向外力麼擠時，先使鉚釘頭接 觸而形成外部短路’進而可達到提升電池❹之安全性的目 的。 【實施方式】 本發明減-種方形電池之端蓋板結構，可提升電池使 用之安全。為了使本發明之敘述更加詳盡與完備，可參照下 列描述並配合第1圖至第4圖之圖示。 明參知第1圖’第1圖係繪示依照本發明一較佳實施例 的-種方形電池之端蓋板結構之上視圖。此方形電池之端蓋 板結構⑽至少包括方形平板1〇2與柳釘頭ιΐ2，其中娜釘 頭112位於方形平板102之表φ⑽上，且卿釘頭ιΐ2與方 1234307 !平板102分屬具不同電性之電極，分別載送不同電性之雷 荷。在本發明之較佳實施例中，方形電池可例 池’方形千板102之材質可例如為紹，而鉚 方形平板102為正極。鉚釘 2為負極， 之表面104的中央區域上 X疋立於方形平板102 域上且此鉚釘頭112將方形平板 =面⑽區分成兩側，其中—側為平面區⑽，另—侧則 面區n。。平面區1(38與平面區11。鄰近鉚釘頭112, 且平面區110較佳是 平乂住疋圍繞在鉚釘頭112之三侧 割鄰近在柳釘頭112之另一侧，以使柳釘頭112= 區110位於方形平板102之同一 ^ ^ F 11Λ ^ Α η千面Qi〇8之尚度低於 二=0,針頭112與方形平板1〇2之間更具有絕緣層 6,如第3圖所示’以隔離鉚釘頭112與方形平板⑽。 絕緣層m亦可延伸到柳釘頭112之長㈣與平㈣… 之間的空間’而鉚钉頭112之短側壁與方形平ι〇2之平面 Π及平面區110之間的空間僅以間隙區隔，並無絕緣 層，如第1圖所示。然而’值得注意的一點是，絕緣層ιΐ6 亦可延伸到鉚釘頭112之短側壁與方形平102之平面區 108及平面區110之間，只要鉚釘頭112之短側壁與方形平 板102之平面區108及平面區n〇之間的空間具有間隙即 可。方形平板102上更具有注液口 122，以供電解液 池。 本發明之一特徵就是鉚釘頭之短側壁與平面區1〇8 及平面區11 〇 t間的空間具有間隙，因此可在端蓋板結構 1〇〇受壓變形時’確保平㈣108之方形平板1〇2能接觸到 !234307 鉚釘頭1 1 2。 請參照第2圖，第2圖係繪示依照本發明一較佳實施例 的—種方形電池之端蓋板結構之下視圖。方形平板1〇2另外 具有102相對於表面104之表面1〇6，其中此表面ι〇6為一 平面。在本發明之較佳實施例中，方形平板1〇2之表面ι〇6 ^具有溝槽114貫穿表面106之短軸。其中，溝槽ιΐ4較佳 是呈v型，且溝槽114並未通過鉚釘頭112之下方。溝槽 二4較佳是位於相對於平面區1〇〇之表面1〇6上❹然而，^ 得注意的一點是，溝槽114亦可位於相對於平面區1〇8之表 面106上。 请參照第3 ®，第3圖係繪示沿第丨圖方形電池之端蓋 板結構之Η剖面線所獲得之剖面圖。由於平面區HO高 於平面區108,且表面1()6為平面，因此平面區m之方形 平板1〇2 &厚度大於平面㊣1〇8之方形平板1〇2的厚度。如 此來，平面區108之結構強度會小於平面區11〇之結構強 :，而在平面1 1〇8與平面區11〇之交界形成一處結構弱 ·.、。絕緣層116位於鉚釘頭112與方形平板1〇2之表面ι〇4 之間，藉以電性隔離方形平板1〇2與鉚釘頭112。在本發明 之較佳實施例中，溝槽114位於相對於平面區ιι〇之第二表 上，且溝槽114處之方形平板1〇2的厚度明顯較周圍 :方形平板1〇2的厚度薄。因此’溝槽114處之結構強度會 降低，而形成另一處結構弱點。 睛參照第4圖，第4圖係繪示本發明—較佳實施例的一 方形電池之端蓋板結構經γ方向壓扁測試後之剖面圖。 Ϊ234307 由於平面區108之結構強度較低，因此當電池之侧向豎立面 又到方向117(即Y方向）之壓力時，位於平面區1〇8這一側 之方形平板102會先形變並凸起，而在平面區1〇8上產生彎 折120。再加上鉚釘頭112之短側壁與平面區1〇8及平面區 11 〇之間的空間具有間隙，如此一來將使得平面區j 〇8之方 形平板102接觸到鉚釘頭112。另一方面，由於溝槽ιΐ4處 之方形平板102之結構強度也較周圍之方形平板1〇2低，因 此電池之側向豎立面受到方向117之壓力時，溝槽ιΐ4處之 方形平板102會先形變而在平面區11〇上產生彎折ιΐ8，進 而使平面區11〇之方形平板102接觸到鉚釘頭112。當平面 區108以及平面@ 110之方形平板1〇2接觸到鉚釘頭112 時，均會在電池外部形成正負極短路。如此一纟，可在電池 因外力而產生側向變形時，先於端蓋板結構1〇〇上發生外邙 短路，藉以避免因電池内部短路而導致溫度升高進而產生爆 方开受側向M力而變形時，端蓋板結構 =下:板102與鉚釘頭112形成正負極短路，而使短 路電阻下降，且短路電流平均分布於方形平板ι〇2上。因 此’可有效避免局部高熱產生。 吻參照第5圖’第5圖係㈣依照本發明另—較佳 例的一種方形電池之端蓋板結 實 至少包衽褥之上視圖。端羞板結構200 與鉚釘頭212,其中鉚釘頭212位於 204上’且鉚釘頭212胃方形平板202 電極"別載送不同電性之電荷。在本發 1234307 明之較佳實施例中，方银Φ “例τ方形電池可例如為鋰離子電池，方形平 2反二2二材質可例如為銘，而鉚釘頭212為負極，方形平板 為極。鉚釘頭212較佳是位於方形平板202之上表面 2〇4的中央區域上。在鉚釘頭212外，方形平板 綱區分成二平面㈠06、平面區、與平面…平: 區208與平面區21〇分別位於方形平板2〇2之兩長軸，而二 平面區206則位於方形平板2〇2之兩短轴上。二平面區1234307 Description of the invention [Technical field to which the invention belongs] The present invention relates to an end cover structure of a square battery, and more particularly to an end cover structure of a square lithium ion battery. [Previous Technology] With the development of portable electronic products to be light, thin, short, and small, and the requirements for the increase in the available time for a single charge of portable electronic products, small, lightweight and high energy density secondary batteries are Become an indispensable component of portable electronic products. Among secondary batteries, lithium-ion batteries have the advantages of high operating voltage, high energy density, light weight, and long life, and can meet the demand for lightweight portable electronic products. Therefore, lithium-ion batteries have been widely used in portable electronic products, such as notebook computers (Noteb00k), personal digital assistants (PDA1 Digital Assistant; PDA), and mobile phones (Mobile Phone). ) Equal degrees, the safety design of the end cover of the bell-ion battery is mainly a safety valve design and a conductive sheet under the end cover. The safety valve is designed to prevent the battery from exploding when the pressure inside the battery is raised. However, the safety valve design has no protection against battery deformation. In addition, the design of the conductive sheet under the end cover is designed for the battery to be erected flat in the side direction, that is, when the γ direction is crushed (Υ Crush), the conductive sheet is first brought into contact with the battery can to create an external short circuit to avoid the battery. The interior exploded due to overheating. 1234307 [Summary of the invention] Therefore, the object of the present invention is to provide an end cover structure of a square battery. Only the structural design of the end cover needs to be changed, and an external short circuit can be generated when the battery is deformed laterally without the need for additional A conductive sheet is disposed under the end cover. Therefore, the manufacturing process can be simplified. Another object of the present invention is to provide an end cover structure of a square battery with a rivet head as a partition. The thickness of the planar structure on one side of the end cover is thinner than the thickness of the other side. As a result, the structural strength of the plane with the thinner end plate is weaker than that of the plane with the thicker side. When the square battery is flattened in the γ direction, the thinner flat surface of the cover plate will deform and be convexly curved. The flat surface of the convex end plate contacts the rivet head, which will cause an external short circuit when the square battery deforms. path. Therefore, the safety of the battery in use can be improved. Another object of the present invention is to provide an end cover structure of a square battery, and the back surface of the end cover includes at least a V-shaped groove penetrating the short axis of the end cover. Because the end cover has a weak structural strength at the V-shaped groove, when the square battery is flattened in the Υ direction, the V-shaped groove will first deform to make the end cover surface convex and contact the rivet head. Paths that cause external short circuits. This reduces the risk of battery deformation. Another object of the present invention is to provide an end cover structure of a square battery with a gap without insulation between the short side wall of the rivet head and the flat area of the square flat plate. Therefore, when the end cover is convexly deformed, Effectively increase the contact probability between the square flat plate and the rivet head. According to the above object of the present invention, an end cover structure 1234307 of a square battery is provided. The structure at least includes: a square flat plate having an opposite first surface and a first surface v, wherein the first surface is a plane; and a rivet head is located at The first surface of the square flat plate is separated from the first surface of the square flat plate into a flat area and a second flat area, wherein the height of the first flat area is lower than the height of the first flat area, and The first planar area and the second planar area are adjacent to the rivet head described above. According to a preferred embodiment of the present invention, the above-mentioned square flat plate further includes at least a V-shaped groove located on the second surface of the square flat plate and penetrating the second surface = axis 0 because the first flat area and the second flat surface on both sides of the rivet head The thicknesses of the regions are different, which makes the structure of the first planar region more fragile. In addition, the first surface of the square flat plate has a 4 v-shaped groove running through the second surface with a short axis. Therefore, the square flat plate can first contact the rivet head to form an external short circuit when the square battery is squeezed by the external force in the γ direction, thereby achieving the purpose of improving the safety of the battery. [Embodiment] The present invention reduces the type of end cover structure of a square battery, which can improve the safety of battery use. In order to make the description of the present invention more detailed and complete, please refer to the following description and cooperate with the diagrams of Figs. Refer to FIG. 1 for reference. FIG. 1 is a top view showing an end cover structure of a square battery according to a preferred embodiment of the present invention. The end cover structure of this square battery includes at least a square flat plate 102 and a rivet head 2, where the nail head 112 is located on the table φ⑽ of the square flat plate 102, and the nail head 2 and square 1234307 are different from each other. Electrical electrodes carry lightning charges of different electrical properties, respectively. In a preferred embodiment of the present invention, a rectangular battery can be exemplified. The material of the square rectangular plate 102 is, for example, Shao, and the square plate 102 is a positive electrode. The rivet 2 is a negative electrode, and the central area of the surface 104 of the rivet X stands on the field of the square flat plate 102 and the rivet head 112 divides the square flat plate = face 成 into two sides, where one side is a flat area ⑽ and the other side is a face District n. . Plane area 1 (38 and plane area 11. Adjacent to the rivet head 112, and the plane area 110 is preferably flat 乂 around the three sides of the rivet head 112 cut adjacent to the other side of the rivet head 112 to make the rivets The head 112 = the area 110 is located on the same square plate 102 ^ ^ F 11Λ ^ Α η Qian Qian Qi0 is lower than two = 0, and the needle 112 and the square plate 102 have an insulating layer 6 as shown in the figure. As shown in Figure 3, 'to isolate the rivet head 112 from the square plate ⑽. The insulation layer m can also extend to the space between the long ridge and flat ridge of the rivet head 112' and the short side wall of the rivet head 112 and the square flat ι The space between the plane Π and the plane area 110 is only separated by a gap, and there is no insulation layer, as shown in Figure 1. However, it is worth noting that the insulation layer ιΐ6 can also extend to the rivet head 112. Between the short side wall and the flat area 108 and the flat area 110 of the square flat 102, as long as there is a gap between the space between the short side wall of the rivet head 112 and the flat area 108 and the flat area no of the square flat plate 102. On the square flat plate 102 It also has a liquid injection port 122 for the electrolyte pool. One feature of the present invention is the short side wall and flat area 108 of the rivet head. There is a gap between the space between the flat area and 11 区 t, so that when the end cover structure 100 is deformed under pressure, 'ensure that the square plate 108 of the flat ㈣ 108 can contact the 234307 rivet head 1 1 2. Please refer to section FIG. 2 is a bottom view of an end cover structure of a square battery according to a preferred embodiment of the present invention. The square flat plate 102 has a surface 106 opposite to the surface 104, wherein The surface ι〇6 is a plane. In a preferred embodiment of the present invention, the surface of the square flat plate 102 has a minor axis through which the groove 114 penetrates the surface 106. Among them, the groove ι4 is preferably v And the groove 114 does not pass under the rivet head 112. The groove 2 is preferably located on the surface 106 that is 100 relative to the flat area. However, it is important to note that the groove 114 also It can be located on the surface 106 opposite to the flat area 108. Please refer to Figure 3 ®, which is a cross-sectional view taken along the line Η of the end cover structure of the square battery in Figure 丨. Since the flat area HO It is higher than the flat area 108, and the surface 1 () 6 is flat, so the square flat plate 10 of the flat area m & thickness The thickness of the square flat plate 102 which is larger than the plane ㊣108. In this way, the structural strength of the plane area 108 will be smaller than the structure strength of the plane area 110, and formed at the boundary between the plane 1108 and the plane area 110. A weak structure ... The insulating layer 116 is located between the rivet head 112 and the surface ι04 of the square flat plate 102, thereby electrically isolating the square flat plate 102 and the rivet head 112. In the preferred implementation of the present invention, In the example, the groove 114 is located on the second table relative to the flat area, and the thickness of the square flat plate 102 at the groove 114 is significantly smaller than the surroundings: the square flat plate 102 is thinner. Therefore, the structural strength at the 'trench 114' will be reduced, and another structural weakness will be formed. Referring to FIG. 4, FIG. 4 is a cross-sectional view showing a structure of an end cover plate of a rectangular battery according to the preferred embodiment of the present invention after the flattening test in the γ direction. Ϊ234307 Due to the low structural strength of the flat area 108, when the pressure on the side of the battery is in the direction 117 (ie, the Y direction), the square flat plate 102 on the side of the flat area 108 will be deformed and convex first. Bends 120 on the flat area 108. In addition, there is a gap between the short side wall of the rivet head 112 and the flat area 108 and the flat area 110, so that the square flat plate 102 in the flat area j 08 will contact the rivet head 112. On the other hand, since the structural strength of the square flat plate 102 at the four grooves is also lower than that of the surrounding square flat plate 102, when the lateral vertical surface of the battery is subjected to the pressure of the direction 117, the square flat plate 102 at the four grooves will be First deformed to produce a bend 8 in the flat area 110, so that the square flat plate 102 in the flat area 110 contacts the rivet head 112. When the flat area 108 and the square flat plate 102 of the flat @ 110 contact the rivet head 112, a positive and negative short circuit will be formed outside the battery. In this way, when the battery is deformed laterally due to external force, an external short circuit occurs before the end cover structure 100, so as to avoid the temperature rise caused by the internal short circuit of the battery and the side opening. When the M force deforms, the end cover structure = lower: the plate 102 and the rivet head 112 form a positive and negative short circuit, which reduces the short circuit resistance, and the short circuit current is evenly distributed on the square flat plate ι02. Therefore, 'can effectively avoid local high heat generation. Referring to Fig. 5 ', Fig. 5 is a top view of a square battery according to another preferred embodiment of the present invention. The end plate structure 200 and the rivet head 212, wherein the rivet head 212 is located on 204 'and the rivet head 212 is a square flat plate 202 electrode " Don't carry different electric charges. In the preferred embodiment of the present invention 1234307, the square silver Φ "for example, a square battery can be, for example, a lithium-ion battery, the square flat 2 anti 22 22 material can be, for example, an inscription, and the rivet head 212 is a negative electrode, and the square flat plate is an electrode. The rivet head 212 is preferably located on the central area of the upper surface 204 of the square flat plate 202. Outside the rivet head 212, the square flat plate is divided into two planes ㈠06, a flat area, and a flat surface ... Flat: area 208 and flat area 21 ° is located on the two major axes of the square flat plate 202, and the two-plane area 206 is located on the two short axes of the square flat plate 202. The two-plane area
206平面區208與平面區210分別鄰近鉚釘頭212之四侧。 平面區208之高度與平面區21〇之高度相等，二平面區 之高度則較平面區208與平面區21〇高。鉚釘頭212與方形 平板202之間更具有絕緣層216，以隔離鉚釘頭212與方形 平板202。絕緣層216亦可延伸到鉚釘頭212之側壁與平面 區206之間的空間。方形平板202上更具有注液口 222，以 供電解液注入電池。在此較佳實施例中，方形平板2〇2之下 表面為'一平面。The 206 plane area 208 and the plane area 210 are respectively adjacent to the four sides of the rivet head 212. The height of the planar area 208 is equal to the height of the planar area 21 °, and the height of the two planar areas is higher than the planar area 208 and the planar area 21 °. An insulating layer 216 is further provided between the rivet head 212 and the square flat plate 202 to isolate the rivet head 212 from the square flat plate 202. The insulating layer 216 may also extend to the space between the side wall of the rivet head 212 and the flat area 206. The square flat plate 202 further has a liquid injection port 222 for the electrolyte to be injected into the battery. In this preferred embodiment, the lower surface of the square flat plate 202 is a plane.
由於平面區206高於平面區210與平面區208,且方形 平板202之下表面為平面，因此平面區2〇6之方形平板2〇2 的厚度大於平面區210與平面區208之方形平板202的厚 度。如此一來，平面區21〇與平面區2〇8之結構強度會小於 平面區206之結構強度，而在平面區208以及平面區210 與平面區206之交界形成結構弱點。 由於平面區210與平面區208之結構強度較低，因此當 電池之側向豎立面受到Υ方向之壓力時，位於平面區2 i 〇 與平面區208之方形平板2〇2會先形變並凸起，而使平面區 12 1234307 0與平面區208之方形平板202接觸到鉚釘頭2ί2。 由上述本發明較佳實施例可知，本發明之一優點就是因 為：釘頭兩側之方形平板之厚度不同，再加上方形平板之第 '、有貝穿第-表面紐軸之V型溝槽，而端蓋板結構 ::侧的結構較為脆弱。如此一來，可在電池侧向豐立面受 力壓私B夺，先使方形平板與娜釘頭接觸而形成外部短 因此，可達到提高電池使用之安全性的目的。Since the flat area 206 is higher than the flat area 210 and the flat area 208, and the lower surface of the square flat plate 202 is flat, the thickness of the square flat plate 202 of the flat area 206 is larger than the square flat plate 202 of the flat area 210 and the flat area 208. thickness of. As a result, the structural strength of the planar area 21 and the planar area 208 will be less than the structural strength of the planar area 206, and a structural weakness will be formed at the boundary of the planar area 208 and the planar area 210 and the planar area 206. Because the structural strength of the flat area 210 and the flat area 208 is low, when the lateral vertical surface of the battery is subjected to the pressure in the direction of Υ, the square flat plate 2 located in the flat area 2 i 〇 and the flat area 208 will be deformed and convex first. Then, the flat area 12 1234307 0 and the square flat plate 202 of the flat area 208 are brought into contact with the rivet head 2 2. As can be seen from the above-mentioned preferred embodiments of the present invention, one of the advantages of the present invention is that: the thickness of the square flat plate on both sides of the nail head is different, plus the V-shaped groove of the square flat plate and the penetrating-surface button shaft Slot, while the end cover structure: the side structure is more fragile. In this way, the battery can be squeezed on the side of the battery, and the square flat plate is first contacted with the nail head to form an external short. Therefore, the purpose of improving the safety of battery use can be achieved.
由上述本發明較佳實施例可知，本發明之再一優點就是 因為鉚釘頭之短側壁與方形平板之平面區之間具有間隙，因 此在端蓋板凸起形變時，可大幅提升方形平板與鉚釘頭之接 由上述本發明較佳實施例可知，本發明之又一優點就是 因為電池受側向壓力而變形時，端蓋板結構之方形平板會與 鉚釘頭形成正負極短路。如此一來，可使短路電流平均分布 於方形平板上。因此，可有效避免局部高熱產生，進而可避 免因電池變形所引發之安全性問題。 雖然本發明已以一較佳實施例揭露如上，然其並非用以 限定本發明，任何熟習此技藝者，在不脫離本發明之精神和 範圍内，當可作各種之更動與潤飾，因此本發明之保護範圍 當視後附之申請專利範圍所界定者為準。 【圖式簡單說明】 第1圖係繪示依照本發明一較佳實施例的一種方形電 池之端蓋板結構之上視圖。 13 1234307 第圖係％不依照本發明一較佳實施例的一種方形電 '之端蓋板結構之下視圖。 第3圖係缘示沿第1圖方形電池之端蓋板結構之I - I 剖面線所獲得之剖面圖。 第4圖係繪示本發明一較佳實施例的一種方形電池之 端蓋板結構經Y方向壓扁測試後之剖面圖。 第5圖係緣示依照本發明另一較佳實施例的一種方形 電池之端蓋板結構之上視圖。 【元件代表符號簡單說明】 100 ： 端蓋板結構 222 :注液口 102 ： 方形平板 104 :表面 106 ： 表面 1〇8 :平面區 110 ： 平面區 112 :鉚釘頭 114 ： 溝槽 116 :絕緣層 118 ： 彎折 120 :彎折 122 ： 注液口 2〇〇 :端蓋板結構 202 ： 方形平板 204 :表面 206 ： 平面區 2 0 8 ·平面區 210 ： 平面區 212 :鉚釘頭 216 ： 絕緣層It can be known from the above-mentioned preferred embodiments of the present invention that another advantage of the present invention is that there is a gap between the short side wall of the rivet head and the flat area of the square flat plate, so when the end cover is convexly deformed, the square flat plate and the The connection of the rivet head can be seen from the foregoing preferred embodiments of the present invention. Another advantage of the present invention is that when the battery is deformed by lateral pressure, the square flat plate of the end cover structure will form a positive and negative short circuit with the rivet head. In this way, the short-circuit current can be evenly distributed on the square flat plate. Therefore, local high heat can be effectively avoided, and the safety problem caused by battery deformation can be avoided. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make various changes and decorations without departing from the spirit and scope of the present invention. The scope of protection of the invention shall be determined by the scope of the attached patent application. [Brief Description of the Drawings] FIG. 1 is a top view showing an end cover structure of a square battery according to a preferred embodiment of the present invention. 13 1234307 The figure is a bottom view of an end cover structure of a square electric device according to a preferred embodiment of the present invention. Fig. 3 is a cross-sectional view taken along the line I-I of the end cover structure of the square battery in Fig. 1. FIG. 4 is a cross-sectional view of a square battery end cover structure after a flattening test in the Y direction according to a preferred embodiment of the present invention. Fig. 5 is a top view of an end cover structure of a rectangular battery according to another preferred embodiment of the present invention. [Simple description of component representative symbols] 100: End cover structure 222: Filling port 102: Square flat plate 104: Surface 106: Surface 108: Flat area 110: Flat area 112: Rivet head 114: Groove 116: Insulation layer 118: Bend 120: Bend 122: Fill port 200: End cover structure 202: Square flat plate 204: Surface 206: Flat area 2 0 8 · Flat area 210: Flat area 212: Rivet head 216: Insulation layer