CN109962204B

CN109962204B - Battery cover plate assembly, single battery, battery module, power battery and electric automobile

Info

Publication number: CN109962204B
Application number: CN201711408952.7A
Authority: CN
Inventors: 蒋露霞; 程晗; 周江涛; 杨珂利; 汤道毅
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2017-12-22
Filing date: 2017-12-22
Publication date: 2020-12-25
Anticipated expiration: 2037-12-22
Also published as: CN109962204A; WO2019120236A1

Abstract

The disclosure relates to a battery cover plate assembly, a single battery, a battery module, a power battery and an electric automobile. The battery cover plate assembly comprises a cover plate, an inner leading piece and an electrode outer terminal, wherein the inner leading piece and the electrode outer terminal are electrically connected through a current interruption device, the current interruption device scoring piece comprises a scoring area formed with a scoring line, a first welding area used for being electrically connected with an overturning piece and a second welding area used for being electrically connected with the inner leading piece, the first welding area, the scoring area and the second welding area are sequentially arranged in a strip shape on the vertical section of the scoring piece perpendicular to the length direction of the cover plate, and the scoring line extends along the length direction of the cover plate on the scoring area. The electrical connection between the first bonding area and the second bonding area can also be broken by breaking the notch, thereby interrupting the current. In addition, the scoring piece arranged in a strip shape can effectively save the size of the scoring piece in the width direction, and the whole current interruption device is favorable for not exceeding the range of the cover plate in the width direction.

Description

Battery cover plate assembly, single battery, battery module, power battery and electric automobile

Technical Field

The present disclosure relates to the field of batteries, and in particular, to a battery cover assembly, a battery cell using the battery cover assembly, a battery module using the battery cell, a power battery using the battery module, and a vehicle using the power battery.

Background

The battery is used as an energy storage unit and plays an important role in various industries, for example, the power battery is widely used in the fields of new energy vehicles and the like, wherein a battery pack of the power battery can be internally provided with a battery module formed by a plurality of single batteries which are connected in series or in parallel so as to realize charging and discharging operations. In the charging and discharging process of the power battery, the state of charge is usually calculated by monitoring the change of voltage and current through a BMS (battery management system). If the voltage sampling is problematic, the battery can be overcharged, and particularly in the case of a ternary system, the battery is more dangerous to burn and explode if the overcharge reaches a certain degree.

The prior technical scheme is as follows: the voltage and the current of the battery are monitored, the electric quantity of the battery is calculated by a current integration method and an open-circuit voltage method, and the charge and discharge management of the battery is controlled according to the electric quantity. However, the method has disadvantages, such as failure of voltage sampling or current sampling of the battery, or failure of software, which results in that the battery cannot be controlled for long-time charging, especially in the case of charging of the charging pile, when the communication between the charging pile and the battery manager fails, the overcharge cannot be controlled, and the overcharge of the battery to a certain extent may cause the battery to swell, even explode and catch fire.

Therefore, it is of positive significance to provide a current interruption technique capable of forcibly turning off the charge and discharge circuit by itself.

Disclosure of Invention

The purpose of the present disclosure is to provide a battery cover plate assembly, a single battery using the battery cover plate assembly, a battery module using the single battery, a power battery using the battery module, and a vehicle using the power battery.

In order to accomplish the above object, the present disclosure provides a battery cover plate assembly including a cover plate, an inner lead member positioned at an inner side of the cover plate, and an electrode outer terminal positioned at an outer side of the cover plate, the inner lead member and the electrode outer terminal are electrically connected by a current interrupt device including a score member and an inversion member, the scoring member comprises a scoring area formed with a scoring line, a first welding area used for being mutually and electrically connected with the turnover member and a second welding area used for being electrically connected with the inner leading-out member, the flip-up member is capable of being actuated by air pressure to break the score to electrically disconnect the score member, on a vertical section of the scored piece perpendicular to the length direction of the cover plate, the first welding area, the scored area and the second welding area are sequentially arranged in a strip shape, and the score extends on the scored area along the length direction of the cover plate.

Alternatively, the score region may be formed as an elongated structure extending in a length direction of the cover plate, the score may extend in the length direction of the elongated structure, and the first weld region and the second weld region may be disposed on both sides in a height direction of the score region.

Optionally, the score is parallel to the first weld zone and the second weld zone, respectively.

Optionally, the end of the score is disposed through to or spaced from the edge of the score region.

Optionally, the end of the score is spaced from the edge of the score region by a distance of 0.01-1 mm.

Optionally, the end of the score is spaced from the edge of the score region by a distance of 0.05-0.5mm

Optionally, the first weld zone, the scored zone, and the second weld zone are sequentially formed in an i-shaped configuration in a height direction.

Optionally, the score is one strip formed on one side of the score region or two strips formed on both sides of the score region.

Alternatively, the turnover member is formed in an elongated structure extending in a length direction of the cover plate, and has first connection regions extending along the first welding areas and welded to each other, the first connection regions being formed in an elongated structure and having lower surfaces formed with welding grooves accommodating the first welding areas.

Optionally, the weld groove is an n-shaped groove to weld with both side edges of the first weld zone.

Optionally, the electrode outer terminal is electrically connected to the flip member, the score member is electrically connected to the inner lead member, the flip member has a second connection region formed in an elongated structure, a support ring is hermetically connected between a lower side of the second connection region and the cover plate, and an outer peripheral edge of the electrode outer terminal is electrically connected to an upper side of the second connection region.

Optionally, the support ring is formed as an elongate structure extending lengthwise of the cover plate and not beyond the width edge of the cover plate.

Optionally, the inner lead member is formed as a sheet structure having a middle welding area electrically connected to the scored member and an edge welding area electrically connected to the cell, the edge welding area being located outside the middle welding area.

Optionally, the thickness of the edge weld area is equal to or greater than the thickness of the middle weld area.

Optionally, the thickness of the middle welding area is 0.1-1mm, and the thickness of the edge welding area is 1-5 mm.

Alternatively, the edge weld area is formed as an annular connecting area surrounding the middle weld area, or as a strip-shaped weld area on both sides of the middle weld area.

Optionally, the intermediate weld area and the edge weld area are integrally formed or separately connected.

The present disclosure also provides a battery cell, which includes a housing, a battery cell accommodated in the housing, and a battery cover plate assembly encapsulating the housing, wherein the battery cover plate assembly is the battery cover plate assembly provided by the present disclosure, the inner lead member is electrically connected to the battery cell, and the flip member is in gas communication with the inside of the housing.

The present disclosure also provides a battery module, in which the battery cell provided by the present disclosure is disposed.

The present disclosure also provides a power battery, which includes a bag body and a battery module disposed in the bag body, wherein the battery module is the battery module provided by the present disclosure.

The present disclosure also provides an electric vehicle provided with the power battery provided by the present disclosure.

Through the technical scheme, the electric connection between the first welding area and the second welding area can be disconnected through the snapping nicks, and the effect of current interruption is achieved. In addition, the notch pieces are arranged in a strip shape in the vertical direction, and the size of the notch pieces in the height direction is larger than that of the notch pieces in the width direction, so that the size of the notch pieces in the width direction can be effectively saved, and the integral current interruption device is favorable for being not beyond the range of the cover plate in the width direction.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

fig. 1 is a partially exploded perspective view illustrating a battery module according to the present disclosure;

fig. 2 is a partial perspective view of a reversing element of the current interrupt device in an embodiment of the present disclosure;

fig. 3 is a top plan view of a flip piece of an embodiment of the current interrupt device of the present disclosure;

fig. 4 is a schematic perspective view of a unit cell of a cell cover plate assembly according to an embodiment of the present disclosure;

FIG. 5 is a schematic perspective view of a first configuration of a scoring member of a current interrupt device in accordance with an embodiment of the present disclosure;

FIG. 6 is a schematic perspective view of a second configuration of a scoring member of a current interrupt device in accordance with an embodiment of the present disclosure;

FIG. 7 is a schematic perspective view of a third configuration of a scoring member of a current interrupt device in accordance with an embodiment of the present disclosure;

fig. 8 is a cross-sectional view of a battery cover plate assembly based on the scoring member of fig. 5 in an embodiment of the present disclosure;

fig. 9 is a cross-sectional view of a battery cover plate assembly based on the scoring member of fig. 7 in an embodiment of the present disclosure;

FIG. 10 is a schematic view of a portion of an inner lead member in accordance with an embodiment of the present disclosure;

fig. 11 is a partial schematic view of another inner lead member according to an embodiment of the present disclosure.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are intended for purposes of illustration and explanation only and are not intended to limit the present disclosure.

In the present disclosure, unless otherwise specified, use of directional words such as "upper, lower, left and right" is generally defined with reference to the drawing direction of the corresponding drawing, and "inner and outer" refer to the inner and outer of the outline of the corresponding component.

As shown in fig. 1 to 11, the present disclosure provides a current interrupt device, a score member, a flip member, a battery cover plate assembly using the current interrupt device, a unit battery using the battery cover plate assembly, a battery module using the unit battery, a power battery using the battery module, and a vehicle using the power battery. Wherein a current interrupt device is provided between the electrode outer terminal 112 and the internal cell for cutting off the circuit inside and outside the battery, as shown in fig. 1. Among the single batteries, a plurality of single batteries are connected in series or in parallel to form a battery module and can be placed in a battery pack to form a power battery. In addition, besides the field of power batteries, various technical schemes provided in the disclosure can also be widely applied to other battery fields. In particular, the present disclosure presents the current interruption device concerned by two embodiments. Various embodiments will be described in detail below with reference to the accompanying drawings.

First, as shown in fig. 1 and 4, a battery module is provided in an embodiment of the present disclosure, which includes a plurality of unit batteries, wherein the unit batteries may include a case 111, a battery cell accommodated in the case, and a cover plate 110 encapsulating the case, wherein an electrode outer terminal 112 is provided on the cover plate for accomplishing input and output of current through various electrode lead-outs 119. As shown in fig. 8, the cell cover plate assembly further has an inner lead 109 to which the cells are electrically connected, and a current interrupt device is provided between the electrode outer terminal 112 and the inner lead 109 so that input and output of current to and from the electrode terminal can be controlled. That is, the current interrupt device is in a state of conducting the battery cell in a conventional state in the single battery, at the moment, the electrode terminal can normally perform current input and output so as to complete the charging and discharging work of the single battery, and in a dangerous state, for example, when the battery is overcharged, the current interrupt device can interrupt the current input and the current output of the electrode terminal, so that the problems of overcharging and the like of the battery are avoided. Therefore, as an important safety measure, the reliability of the current interruption device is of crucial importance, i.e. a fast response of the current interruption device is required.

In the present disclosure, the current interrupt device in each embodiment is a mechanical structure that senses air pressure, and specifically, the current interrupt device is in gas communication with the inside of the housing of the unit cell and can act to interrupt the current flowing therethrough under the air pressure. Specifically, the transmission of current can be interrupted by disconnecting the internal components, thereby timely cutting off the charge and discharge of the battery. The air pressure sources used are: when dangerous states such as overcharge of the battery occur, gas is generated inside the battery and then the gas pressure inside the housing is increased, or when the battery is abnormal during use, the temperature of the battery is increased and the gas pressure inside the battery is increased, so that the gas pressure power for driving the current interrupting device is generated.

Taking the embodiment as shown in fig. 8 as an example, the current interrupt device has a scoring member 101 and a flip member 102 connected to the scoring member 101 to be electrically connected to each other, and the flip member 102 and the scoring member 101 can be electrically disconnected under the action of air pressure. In the embodiment of the present disclosure, for the purpose of self-breaking at least one of the two, for example, the breaking of the self-structure is realized by processing a weak score on the corresponding component, so as to break the electrical connection, specifically, the score 104 is formed on the score member 101. That is, the score 104 is broken by the turning operation of the flipper 102 by the internal air pressure, and the electric connection between the two is disconnected, thereby cutting off the transmission of the current.

In this way, it is considered that since the current to be passed is large in the field of, for example, a power battery, it is necessary to ensure the stability of the welding structure of the nicking member 201 and the turning member 202 and to avoid the high current from fusing the welding structure. Thus, by arranging the score 104 of the scoring member 101 so that a weakened portion having a strength smaller than that of the other portions is formed at the corresponding portion, complete disconnection of the scoring member 101 and the reversing member 102 can be accomplished

In the embodiment of the present disclosure, as shown in fig. 2 and 3, the flip-up member 102 is a sheet structure forming a taper shape, a small end of the taper shape is formed as a first connection region 115, and a large end is far away from the score member 101 and is formed as a second connection region 116. The tapered structure can dispose the two connecting areas in different planes and can provide a space for the flip member 102 to be forced to flip upwards to break the score 104. In other possible embodiments, the turnover part can also be a plane part with elasticity or the like.

As shown in fig. 8 and 9, in the embodiment of the present disclosure, in order to ensure that gas inside the battery can act, a support ring 113 is sealingly connected between the lower side of the outer circumference of the inverter 102 and the cap plate 110, and the outer circumference of the electrode outer terminal 112 is electrically connected to the upper side of the outer circumference of the inverter 102, so that gas generated from the inside of the battery can act on the inverter 102 without leaking. And in order to enable the flip 102 to normally operate, the electrode outer terminal 112 is formed in a cap structure and may be formed with a through hole 118 for discharging gas when the flip 102 operates, thereby preventing the flip from operating reversely under the gas pressure. In addition, in both the embodiments of the cover plate 110 with electricity and insulation, the support ring 113 may be made of an insulating material or a conductive material. Generally, the support ring 113 may be a ceramic ring to insulate the cap plate 110 from electricity.

As shown in fig. 2 and 3, the battery cover plate assembly provided by the embodiment of the present disclosure includes an overturning member 102 formed as an elongated structure extending in a length direction of the cover plate 110 on the basis of the foregoing embodiment. The long structure in the present context means that in a cross section of the long structure parallel to the cover plate, the dimension in the length direction of the cover plate is larger than the dimension in other directions. Therefore, as shown in fig. 4, since the flip member 102 is formed in an elongated structure extending in the length direction of the cover plate, it is possible to reduce the possibility that, for example, the portion of the current interrupt device including the flip member 102 in fig. 1, which is exposed to the cover plate 110, exceeds the cover plate 110 in the height direction while ensuring the contact area with the internal gas, and even as shown in fig. 9, it is possible to be completely within the range of the cover plate, thereby avoiding interference with other devices than the cover plate 110, while ensuring the sensitivity of flipping.

As shown in fig. 2 to 4, in the embodiment of the present disclosure, the end of the elongated structure in the length direction is arc-shaped, that is, the cross section of the elongated structure parallel to the cover plate has a middle rectangular structure and two arc-shaped structures, so that the structure of the cover plate 110 is adapted and the ring-shaped flip piece and other corresponding structures, such as the score piece 101, the support ring 113 and the electrode outer terminal 112, are conveniently formed. In other embodiments, the elongated structure may also be a waist-shaped structure or an oval structure, wherein the major axis of the waist-shaped structure or the oval cross section is along the direction of the cover plate. In some embodiments, the parallel section of the elongated structure and the cross section of the cover plate can also be formed into other shapes such as a rectangular cross section.

In the embodiment of the present disclosure, since the components connected with the inside-out member 102 outside the cap plate 110 are the electrode outside terminal 112 and the support ring 113, it is possible to design both to be also mating elongated structures, and thus, for the connection between the components, at least the second connection region 115 connected with the electrode outside terminal 112 and the support ring 113 in the inside-out member 102 is formed as an elongated structure. Wherein the support ring 113, due to its connection with the cover plate 110, may be designed to form an elongated structure that does not extend beyond the edge of the cover plate 110, in particular the width edge of the cover plate 110, wherein optionally the width edge of the support ring 113 and the edge of the cover plate 110 are aligned. So that the flip 102 obtains a large design and a large force-receiving space.

In the present embodiment, as shown in fig. 2, the first connection region 116 is also formed in an elongated structure extending along the length direction of the cover plate. The end part of the long structure along the length direction is in a circular arc shape, and the long structure can also be in an oval or waist-shaped structure. The corresponding scoring member 101 may be formed as an elongated structure as shown in fig. 5-7.

Continuing with the flip-up member 102 in this embodiment, the flip-up member 102 is formed into a tapered sheet-like structure in a direction perpendicular to the upper surface of the cover plate 110, a first connection region 115 formed by a small end of the taper is formed into an elongated structure, a large end is away from the score member 110 and forms a second connection region 116, and the second connection region 116 is parallel to the first connection region 115 and formed into an elongated structure. Specifically, the second connection region 106 is a flange structure to facilitate simultaneous connection with the support ring 113 and the electrode outer terminal 122.

In the present embodiment, in order to ensure the connection strength, the thickness of each of the first connection region 115 and the second connection region 116 is larger than the thickness of the operation region 123 therebetween. Specifically, the thickness of the first and second attachment areas may be 0.3-3mm, and the thickness of the action area 123 may be 0.05-0.3 mm. This design is equally applicable to the flipper 102 in other embodiments.

As shown in fig. 5 to 7, based on the battery cover plate assembly provided in the embodiments of the present disclosure, the description is continued for three scoring members provided in the present disclosure. Unlike the conventional scoring member in which the score is formed in a ring-shaped configuration, the scoring member 101 provided in the present embodiment is a non-closed-loop elongated score of the score 104. Specifically, on a vertical cross section of the score member 101 perpendicular to the length direction of the cover plate 110, the first welding area 103, the score region 105, and the second welding area 107 are sequentially arranged in a strip shape, and the score 104 extends on the score region 105 along the length direction of the cover plate 110. This also breaks the electrical connection between the first bonding pad 103 and the second bonding pad 107 by breaking the score 104, which acts as a current interrupt. In addition, the notch pieces are arranged in a strip shape in the vertical direction, namely, the size of the notch pieces in the height direction is larger than that of the notch pieces in the width direction, so that the size of the notch pieces 101 in the width direction can be effectively saved, and the whole current interruption device does not exceed the range of the cover plate 110 in the width direction.

In addition, in the present embodiment, the score region 105 is formed as an elongated structure extending in the longitudinal direction of the cover plate, i.e., the dimension in the longitudinal direction of the score is larger than the dimensions in the width direction and the height direction thereof. The score 104 extends along the length of the elongated structure to form a non-closed loop score, optionally the score 104 is a linear score, and in other possible embodiments, the score may be a curved or broken line long-shaped score. And the first welding area 103 and the second welding area 107 are provided on both sides in the height direction of the scored area 105 in order to achieve the stretch-breaking of the score 104. That is, as oriented in the drawing, the first welding area 103, the scored area 105, and the second welding area 107 are sequentially disposed from top to bottom in the height direction so as to be linearly distributed on a vertical section of the scored piece 101 perpendicular to the cover plate 110. Thereby being different from the prior annular scoring member distributed in the radial direction. Thus, after the turnover member 102 is turned over by force, the score 104 can be broken, thereby achieving the purpose of current interruption.

As shown in fig. 5 and 6, in one embodiment, the first welding area 103, the scored area, and the second welding area are sequentially formed in an i-shaped configuration in a height direction, i.e., both sides of the two welding areas protrude from the scored area 105 and may be respectively welded with other parts. When welding with upset piece and motor inner terminal like this, the welding is more stable, avoids appearing the problem that the unexpected disconnection of solder joint appears under the exogenic action. The height direction of scoring member 101 is relative to its length direction, and after being assembled to the cover plate, the height direction is relative to the up-down direction of the cover plate. In another embodiment, the first bonding pad 103, the notch area 105, and the second bonding pad 107 are formed in a zigzag structure in order in the height direction. That is, only one side of the two welding regions protrudes from the indented region 105 and a one-sided welding point can be formed, so that the corners of the zigzag structure can have a buffering effect when being impacted by an external force, thereby protecting the indentations 104 on the indented region 105 between the two welding regions and reducing the possibility of accidental breakage of the indentations 104.

In addition, regardless of the shape of the letter "i" or "Z", in this embodiment, the welding areas of the notch 104 and the two welding areas are disposed on different planes in the height direction or other directions, so as to reduce the influence of heat such as laser welding on the notch.

To accommodate such an elongated score member 101, as shown in fig. 2, the flip member 102 is formed as an elongated structure extending along the cover and disposed parallel to the elongated structure of the score member 101, wherein the flip member 102 has a first connecting region 115 extending along the first welding region 103 and welded to each other, the first connecting region being formed as an elongated structure and having a lower surface formed with a weld recess 124 accommodating the first welding region 103. The solder groove 124 may be an n-shaped groove with an n-shaped cross section or an L-shaped groove with an L-shaped cross section.

Specifically, as shown in fig. 2 and 7, when score member 101 is of an i-shaped configuration, weld groove 124 is an n-shaped groove to be welded, for example, by solder seam welding, to both side edges of first weld zone 103 received therein, thereby stabilizing the electrical connection therebetween.

In addition, as shown in fig. 9, when the scored piece 101 has a zigzag structure, the weld groove 124 may also have an L-shaped structure to be welded to a side edge of the first weld region received therein, which is away from the second weld region, for example, by brazing seam welding. This provides cushioning of the scored region 105 by the corners of the zigzag configuration upon receiving an external force.

In this embodiment, regardless of the i-shaped or Z-shaped structure, or half i-shaped or half Z-shaped, the score 104 may be disposed parallel to the first welding region 103 and the second welding region 107, respectively, so that when the flip member 102 is flipped, the maximum vertical tearing force can be applied to each portion of the score 104 without generating component forces in other directions, thereby providing the sensitivity of the current interrupt device.

In this embodiment, as shown in fig. 5 or 6, the end of the score 104 may be disposed to penetrate the edge of the score region 105 or be spaced apart from the edge of the score region 105. The edge penetrating through the scored region 105 can improve the sensitivity of the current interrupting device, and the interval can ensure that when the internal pressure of the scored piece 101 fluctuates in a low range, the internal pressure of the battery does not influence the score 104 of the scored piece 101, and only when the internal pressure value exceeds a preset value, the internal pressure of the battery can break the score 104.

When the end of the score 105 is spaced apart from the edge of the score region 105, especially when both ends are spaced apart, as shown in fig. 6, the end of the score 104 may be spaced apart from the edge of the score region 105 by 0.01-1mm, and further, the end of the score 104 may be spaced apart from the edge of the score region 105 by 0.05-0.5 mm. Therefore, the sensitivity of the current interruption device can be ensured, and the nick can be prevented from being broken due to the influence of external force or internal air pressure fluctuation.

In both the i-shaped and Z-shaped embodiments of the present embodiment, the thicknesses of the first weld zone 103 and the second weld zone 107 are respectively greater than or equal to the thickness of the scored region 105. It should be noted here that, since the scored region 105 is formed in a plate-like structure, the thickness direction of the scored region is not consistent with the thickness direction of the two welding regions, wherein the thickness direction of the two welding regions is the up-down direction in the drawing, that is, the welding is performed with the side edge of the welding groove, it can be understood that the direction is perpendicular to the cover plate 110, and the thickness direction of the scored region 105 is the direction parallel to the cover plate 110, that is, the width direction of the whole scored member, when the score 104 is formed on the side surface of the scored region 105 extending up and down.

Specifically, the first and

second welding areas

103 and 107 have a thickness of 0.4 to 5mm, and the scored area 105 has a thickness of 0.05 to 1 mm. Further, the thickness of the first and

second welding areas

103 and 107 is 0.8 to 3mm, and the thickness of the scored area 105 is 0.1 to 0.8 mm. Therefore, by setting the thickness of the scored region 105 to be equal to or less than the thickness of the two weld regions, it is possible to secure the welding strength of the weld region and provide a basis for high-quality scoring.

In addition, it is also possible to design the thickness of the first welding region 103 to be equal to or less than the thickness of the second welding 107 region. Therefore, the welding strength can be ensured, and meanwhile, the assembly space of the turnover part 102 is prevented from being occupied, so that the turnover part 102 can be designed to be thicker in the height direction as much as possible to perform a larger turnover action to break the nick 104.

In the present embodiment, the score 104 may be one strip formed on one side of the score region 105 as shown in fig. 6 and 7, or two strips formed on both sides of the score region 105 as shown in fig. 5. When there are two scores 104, the two scores are aligned on both sides of the scored region 105 to enhance the sensitivity of the current interrupt device.

In the present embodiment, as shown in fig. 8 and 9, the turnover member has a second connection region 116 formed in an elongated structure, a support ring 113 is sealingly connected between the lower side of the second connection region 116 and the cap plate 110, and the outer peripheral edge of the electrode outer terminal 112 is electrically connected to the upper side of the second connection region 116. In this way, the support ring may be formed as an elongated structure extending along the cover plate, and further, the support ring may be designed not to exceed the width edge of the cover plate as shown in fig. 9, thereby avoiding interference with other devices outside the battery.

In order to accommodate the assembly of the elongated score member 101, in the battery cover plate assembly provided in the embodiment of the present disclosure, as shown in fig. 8, 10 and 11, the inner lead member 109 is formed in a sheet-like structure having a middle welding region 131 electrically connected to the score member 101 and an edge welding region 132 electrically connected to the cell, the edge welding region 132 being located outside the middle welding region 131. Wherein the thickness of the edge land 132 is equal to or greater than the thickness of the middle land 131. When the thickness of the middle welding area 131 is small, a step structure can be formed with the edge welding area 132 to have a height difference, that is, as shown in fig. 8, the two are not on the same plane in the vertical direction, so that when the edge welding area is welded with the cell tab or other adapters between the cell, the nicking member 101 connected to the middle welding area can be buffered.

Specifically, in order to secure the structural strength and the buffering function, the thickness of the middle land 131 is optionally 0.1 to 1mm, and the thickness of the edge land 132 is optionally 1 to 5 mm. In addition, structurally, as shown in fig. 10, the edge lands 132 are formed as ring-shaped connection regions surrounding the middle lands 131, which is a cut-away partial view, by which the middle lands 131 can be surrounded by the ring-shaped edge lands 132, and as shown in fig. 11, the edge lands may also be strip-shaped lands on both sides of the middle lands 131. I.e. without closing the intermediate welding area 131, so that both ends of the intermediate welding area have openings, falls within the scope of protection of the present invention for such variants. In addition, the middle welding region 131 and the edge welding region 132 may be integrally formed, which may reduce the number of welding parts and simplify assembly, and in some embodiments, may be separately connected, such as by welding, which may increase the buffering effect on the middle welding region.

Further, as shown in fig. 8, the intermediate welding area of the inner lead 109 may be formed with an accommodating groove 133 accommodating the second welding area 107 of the scored piece 101, which extends along the second welding area 107 forming the long structure to form the long structure, and may be a through hole structure penetrating the intermediate welding area in the up-down direction, or may not penetrate, and may be welded to the second welding area 107 by seam welding (soldering, etc.).

The battery cell provided by the present disclosure includes a casing 111, a battery cell accommodated in the casing, and the above-mentioned battery cover plate assembly encapsulating the casing, the inner lead member 109 is electrically connected to the battery cell, and the flip member 102 is in gas communication with the inside of the casing.

The battery module that this disclosure provided is provided with foretell battery cell in this battery module.

The power battery provided by the disclosure comprises a bag body and the battery module arranged in the bag body.

The electric automobile that this disclosure provided is provided with foretell power battery.

The five embodiments of the present disclosure are described in detail with reference to the drawings, however, the present disclosure is not limited to the details of the embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical concept of the present disclosure, and the simple modifications all belong to the protection scope of the present disclosure.

It should be noted that, in the foregoing embodiments, various features described in the above embodiments may be combined in any suitable manner, and in order to avoid unnecessary repetition, various combinations that are possible in the present disclosure are not described again.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. A battery cover plate assembly comprising a cover plate (110), an inner lead-out member (109) positioned inside the cover plate (110), and an electrode outer terminal (112) positioned outside the cover plate (110), the inner lead-out member (109) and the electrode outer terminal (112) being electrically connected by a current interrupt device, the current interrupt device comprising a score member (101) and a flip member (102), the score member (101) comprising a score region (105) formed with a score (104), a first weld region (103) for electrically connecting with the flip member (102) and a second weld region (107) for electrically connecting with the inner lead-out member (109), the flip member (102) being capable of acting under air pressure to electrically disconnect with the score member (101) by breaking the score (104), characterized in that, on a vertical cross section of the score member (101) perpendicular to a length direction of the cover plate (110), the first welding area (103), the scored area (105) and the second welding area (107) are sequentially arranged in a strip shape, so that the dimension of the scored piece (101) in the height direction is larger than that of the scored piece in the width direction, the score extends on the scored area (105) along the length direction of the cover plate (110), and the turnover piece (102) is formed into an elongated structure extending along the length direction of the cover plate (110); the inner leading part (109) is formed into a sheet-shaped structure, the sheet-shaped structure is provided with a middle welding area (131) electrically connected with the scoring part (101) and an edge welding area (132) electrically connected with the battery cell, and the edge welding area (132) is positioned on the outer side of the middle welding area (131); the thickness of the edge land (132) is equal to or greater than the thickness of the middle land (131).

2. The battery cover plate assembly according to claim 1, wherein the scored region (105) is formed as an elongated structure extending in a length direction of the cover plate, the score (104) extends in the length direction of the elongated structure, and the first welding region (103) and the second welding region (107) are disposed at both sides of the scored region (105) in a height direction.

3. The battery cover plate assembly of claim 2, wherein the score (104) is parallel to the first weld zone (103) and the second weld zone (107), respectively.

4. The battery cover plate assembly of claim 2, wherein the ends of the score (104) are disposed through to or spaced from the edge of the score region (105).

5. The battery cover plate assembly of claim 4, wherein the end of the score (104) is spaced from the edge of the score region (105) by a distance of 0.01-1 mm.

6. The battery cover plate assembly of claim 5, wherein the end of the score (104) is spaced from the edge of the score region (105) by a distance of 0.05-0.5 mm.

7. The battery cover plate assembly according to claim 1, wherein the first welding region (103), the scored region (105), and the second welding region (107) are sequentially formed in an i-shaped structure in a height direction.

8. The battery cover plate assembly of claim 1, wherein the score (104) is one strip formed on one side of the score region (105) or two strips formed on both sides of the score region (105).

9. The battery cover plate assembly according to claim 2, wherein the flip has a first connection region (115) extending along the first welding region (103) and welded to each other, the first connection region being formed in an elongated structure and having a lower surface formed with a welding groove (124) receiving the first welding region (103).

10. The battery cover plate assembly according to claim 9, wherein the welding groove (124) is an n-shaped groove to be welded with both side edges of the first welding region (103).

11. The battery cover plate assembly according to claim 9, wherein the electrode outer terminal (112) is electrically connected to the flip member (102), the score member (101) is electrically connected to the inner lead member (109), the flip member has a second connection region (116) formed in an elongated structure, a support ring (113) is hermetically connected between a lower side of the second connection region (116) and the cover plate (110), and an outer circumference of the electrode outer terminal (112) is electrically connected to an upper side of the second connection region (116).

12. The battery cover plate assembly of claim 11, wherein the support ring is formed as an elongated structure extending along a length of the cover plate and not beyond a width edge of the cover plate.

13. Battery cover plate assembly according to any of claims 1-12, characterized in that the thickness of the middle welding area (131) is 0.1-1mm and the thickness of the edge welding area (132) is 1-5 mm.

14. The battery cover plate assembly according to any one of claims 1 to 12, wherein the edge welding region (132) is formed as a ring-shaped connection region surrounding the middle welding region (131), or a bar-shaped welding region at both sides of the middle welding region (131).

15. The battery cover plate assembly according to any of claims 1-12, wherein the middle welding zone (131) and the edge welding zone (132) are integrally formed or separately connected.

16. A battery cell comprising a casing (111), a cell housed inside the casing, and a cell cover plate assembly enclosing the casing, characterized in that the cell cover plate assembly is according to any one of claims 1-15, the inner lead (109) is electrically connected to the cell, and the flip (102) is in gaseous communication with the inside of the casing.

17. A battery module, wherein the unit cells according to claim 16 are provided in the battery module.

18. A power battery, which comprises a bag body and a battery module arranged in the bag body, wherein the battery module is the battery module according to claim 17.

19. An electric vehicle, characterized in that it is provided with a power battery according to claim 18.