CN218300178U

CN218300178U - Battery cover plate assembly, battery and electric equipment

Info

Publication number: CN218300178U
Application number: CN202222226194.XU
Authority: CN
Inventors: 陈代松; 王宝玉; 陈栋; 徐伦; 张耀
Original assignee: Sunwoda Electric Vehicle Battery Co Ltd
Current assignee: Xinwangda Power Technology Co ltd
Priority date: 2022-08-23
Filing date: 2022-08-23
Publication date: 2023-01-13
Anticipated expiration: 2032-08-23

Abstract

The utility model discloses a battery cover plate subassembly, battery and consumer. The utility model discloses a series connection inserts compound safety subassembly between negative terminal or positive terminal and electrically conductive piece, and the fuse-link is can overflow fusing metal fuse, the resistive element with fuse-link parallel connection, insulating-electrically conductive transition body and parallel connection the resistive element with fuse-link series connection. The composite safety assembly is changed into a conductor when the battery is overheated to reach the transition temperature of the insulation-conduction transformation body, the battery forms a short-circuit state through the insulation-conduction transformation body and the fuse body, heavy current discharge is carried out, the residual capacity of the battery is rapidly reduced in the initial stage of short circuit, when the current exceeds the preset current, the fuse body fuses, the resistor body is connected into a circuit, the battery maintains the short-circuit state through the insulation-conduction transformation body and the resistor body, the battery is continuously discharged at a low current, and step-type discharge of the battery can be achieved.

Description

Battery cover plate assembly, battery and electric equipment

Technical Field

The utility model relates to a battery technology field especially relates to a battery cover plate subassembly, battery and consumer.

Background

Along with the popularization of automobile electromotion, the endurance mileage of the electric automobile is continuously improved, the energy density of a power battery is higher and higher, and accidents of electric automobile fire caused by overheating are more frequent. The power battery is likely to overheat under various conditions such as short circuit, overcharge and exposure in external high-temperature environment, and if the energy of the battery cannot be timely and controllably released, worse accidents are likely to be caused.

Currently, most batteries employ a safety element connected between positive and negative electrodes of the battery, and the battery can be rapidly transferred to a short-circuit discharge state when the battery containing the safety element is exposed to high temperature or the temperature of the battery is increased due to external impact. However, the discharge current is not controllable, and if the battery is in a high SOC (state of charge) state, then discharging the battery with a large current may cause the battery temperature to continuously increase uncontrollably, which may result in the battery core to explode.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a battery cover plate subassembly, battery and consumer aims at effectively solving present battery and carries out the short circuit under unusual attitude and discharges, the uncontrollable problem of discharge current.

According to an aspect of the present invention, the present invention provides a battery cover plate assembly, including a positive terminal, a negative terminal, a conductive member, and a composite safety assembly; the positive terminal is electrically connected with the conductive piece, and the negative terminal is electrically connected with the conductive piece through the composite safety component; the composite safety assembly comprises a resistor body, a fuse link and an insulation-conduction transition body, wherein the resistor body is connected with the fuse link in parallel, and the insulation-conduction transition body is connected with the resistor body and the fuse link connected in parallel in series; the insulation-conduction transformation body is an insulator when the temperature does not exceed a preset temperature threshold, and is a conductor when the temperature exceeds the preset temperature threshold; the fuse link is a conductor when the current does not exceed the preset current value, and is fused when the current exceeds the preset current value.

According to the utility model discloses a further aspect, the utility model provides a battery, including electric core, casing, above-mentioned battery cover plate subassembly, electric core is located in the casing, the casing has the opening, battery cover plate subassembly lid is located the opening part.

According to the utility model discloses an on the other hand, the utility model provides an electric equipment, electric equipment includes above-mentioned battery.

The utility model has the advantages that by connecting the composite safety component between the negative terminal and the conductive piece, the composite safety component comprises a resistor body, a fuse body and an insulation-conductive transition body, the resistor body is connected with the fuse body in parallel, and the insulation-conductive transition body is connected with the resistor body and the fuse body which are connected in parallel in series; the insulation-conduction transformation body is an insulator when the temperature does not exceed a preset temperature threshold, and is a conductor when the temperature exceeds the preset temperature threshold; the fuse link is a conductor when the discharge current does not exceed the preset current value, and is fused when the discharge current exceeds the preset current value.

When the temperature of the battery in an abnormal state exceeds a preset temperature threshold value, the insulation-conduction transformation body is a conductor, and the positive terminal and the negative terminal are communicated with the fuse link and the conductive piece through the conductor and the parallel resistor body for discharging; the discharging current is continuously increased in the discharging process, when the current exceeds a preset current threshold value, the fuse link is fused, the resistor body is connected into a circuit, and the positive terminal and the negative terminal discharge with smaller current through the conductor, the resistor body and the conductive piece, so that stepped discharging can be realized.

Drawings

The technical solution and other advantages of the present invention will become apparent from the following detailed description of the embodiments of the present invention with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a battery according to an embodiment of the present invention.

Fig. 2 is an exploded schematic view of a battery cover plate assembly according to an embodiment of the present invention.

Fig. 3 is a schematic perspective view of a composite safety assembly according to an embodiment of the present invention.

Fig. 4 is an exploded schematic view of a composite safety assembly according to an embodiment of the present invention.

Fig. 5 is a cross-sectional view of a composite safety assembly according to an embodiment of the present invention.

Fig. 6 is an equivalent circuit diagram of a composite safety component according to an embodiment of the present invention.

Fig. 7 is a cross-sectional view of a battery cover plate assembly according to an embodiment of the present invention.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. It is to be understood that the disclosed embodiments are merely exemplary of the invention, and are not intended to limit the invention to the precise embodiments disclosed. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; may be mechanically connected, may be electrically connected or may be in communication with each other; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

As shown in fig. 1, for the utility model provides a battery 10, including electric core 100, insulating film 200, casing 300 and battery cover board assembly 400, be provided with anodal utmost point ear 110 and negative pole utmost point ear 120 on the electric core 100, anodal utmost point ear 110 is used for being connected with anodal terminal 421 electricity on the battery cover board assembly 400, negative pole utmost point ear 120 is used for being connected with negative terminal 422 electricity on the battery cover board assembly 400. The battery cell 100 and the insulating film 200 are both disposed in the casing 300, and the insulating film 200 is coated outside the battery cell 100, so as to prevent the battery cell 100 from being short-circuited due to direct contact with the inner wall of the casing 300. In addition, as shown in fig. 1, the upper portion of the housing 300 is opened, and the battery cover assembly 400 is covered at the opening of the housing 300.

In the first embodiment, the explosion structure of the battery cover plate assembly 400 is shown in fig. 2, and includes a conductive member 410, a positive terminal 421, a negative terminal 422, an insulating gasket 430, a composite safety assembly 500, an insulating plate 440, a positive post 451, a negative post 452, and an insulating sealing plug 460. The positive terminal 421 is electrically connected to the upper side of the conductive device 410, a resistor card 470 is further connected in series between the positive terminal 421 and the conductive device 410, and the resistor card 470 is a small-resistance resistor to ensure that the positive terminal 421 is electrically connected to the conductive device 410. The insulating plate 440 is disposed below the conductive member 410, and serves to prevent the battery cell 100 from contacting the conductive member 410 to cause a short circuit. The insulating spacer 430 is disposed between the conductive device 410 and the negative terminal 422, the conductive device 410 is provided with a first via hole 411 and a second via hole 412 which are spaced from each other, the insulating spacer 430 is provided with a third via hole 431 and a receiving hole 432 which are spaced from each other, the insulating plate 440 is provided with a fifth via hole 441 and a sixth via hole 442 which are spaced from each other, and the resistor 470 is provided with a seventh via hole 471. The composite safety assembly 500 is disposed within the receiving hole 432. The first through hole 411, the fifth through hole 441 and the seventh through hole 471 are at corresponding positions, and the positive post 451 is sequentially inserted into the fifth through hole 441, the first through hole 411 and the seventh through hole 471 for electrically connecting the positive tab 110 of the battery cell 100 and the positive terminal 421. The positions of the second via hole 412, the third via hole 431, and the sixth via hole 442 correspond, and the negative pole 452 sequentially penetrates through the sixth via hole 442, the second via hole 412, and the third via hole 431 to electrically connect the negative pole tab 120 of the battery cell 100 and the negative pole terminal 422. The insulating sealing plug 460 is hermetically arranged between the hole wall of the conductive element 410 and the positive pole 451 and the negative pole 452, so as to avoid short circuit caused by direct contact of the positive pole 451 and the negative pole 452 with the conductive element 410. In addition, the insulating sealing plug 460 also seals gaps between the first via hole 411 and the positive post 451, and between the second via hole 412 and the negative post 452.

In some embodiments, as shown in fig. 2, the battery cover plate assembly 400 further includes a positive electrode adapter plate 481 and a negative electrode adapter plate 482, the positive electrode adapter plate 481 is used for electrically connecting the positive electrode tab 110 of the battery cell 100 and the positive electrode post 451, and the negative electrode adapter plate 482 is used for electrically connecting the negative electrode tab 120 of the battery cell 100 and the negative electrode post 452. Specifically, the positive electrode tab 110 of the battery cell 100 is welded and fixed to one surface of the positive electrode adaptor 481 (not shown in the drawings), one end of the positive electrode post 451 is welded and fixed to the other surface of the positive electrode adaptor 481, and the other end of the positive electrode post 451 passes through the fifth via hole 441, the first via hole 411 and the seventh via hole 471 in sequence to be electrically connected to the positive electrode terminal 421. The negative electrode tab 120 of the battery cell 100 is welded and fixed to one surface of the negative electrode adaptor 482 (not shown in the drawings), one end of the negative electrode pillar 452 is welded and fixed to the other surface of the negative electrode adaptor 482, and the other end of the negative electrode pillar 452 sequentially passes through the sixth via hole 442, the second via hole 412, and the third via hole 431 to be electrically connected to the negative electrode terminal 422. In addition, it should be noted that the resistor sheet 470 connected in series between the positive terminal 421 and the conductive member 410 is used for reducing the short-circuit current when the short circuit occurs outside the battery, and in other embodiments, the resistor sheet 470 may be omitted.

Fig. 3 to 6 show a structure of the composite security device 500 according to an embodiment, in which fig. 3 is a schematic perspective view of the composite security device 500, fig. 4 is a schematic exploded view of the composite security device 500, fig. 5 is a cross-sectional view of the composite security device 500, and fig. 6 is an equivalent circuit diagram of the composite security device 500. The structure in which the composite safety assembly 500 is disposed in the receiving hole 432 of the insulating gasket 430 is shown in fig. 7, and the composite safety assembly 500 is connected in series between the conductive member 410 and the negative terminal 422. The conductive member 410 is also electrically connected to the positive terminal 421, that is, the positive terminal 421 is electrically connected to the negative terminal 422 when the composite safety assembly 500 is turned on.

As shown in fig. 3 to 7, the composite security assembly 500 includes a resistor body 523, a fuse body 52, and an insulation-conductive transition body 510. The resistor 523 and the fuse 52 are connected in parallel, and the insulation-conductive transition body 510 is connected in series with the resistor 523 and the fuse 52 connected in parallel.

The insulation-conductive transition body 510 is an insulator when the temperature does not exceed a preset temperature threshold, and is an electrical conductor when the temperature exceeds the preset temperature threshold. In one embodiment, the predetermined temperature threshold, i.e., the phase transition temperature of the insulation-conduction transition body 510 is between 40 ℃ and 70 ℃, and the temperature of the insulation-conduction transition body in this range can indicate that the battery is in a runaway state and short-circuit discharge of the battery is required. And determining a preset temperature threshold value according to the physical characteristics of the insulation-conduction transition body, namely corresponding different temperatures of different insulation-conduction transition bodies to represent the thermal runaway of the battery. Specifically, the material of the insulation-conductive transition body 510 can be vanadium oxide (VOx) or rare earth nickel-based perovskite oxide (ReNiO) ₃ : re = Sm, nd, eu) or vanadium oxide doped with W (tungsten), sr (strontium), la (lanthanum), ba (barium) or rare earth nickel-based perovskite oxide, the phase transition temperature of the insulation-conductive transition body 510 may be set to 68 ℃.

The fuse link 52 is a conductive body when the current does not exceed a preset current value, and fuses when the current exceeds the preset current value. That is, when the discharge current in the circuit is smaller than the preset current value, the fuse link 52 is a conductor, and is connected in parallel with the resistor 523 in the circuit to reduce the resistance of the circuit, so as to realize quick discharge of the battery; when the discharging current continuously increases and is larger than the preset current value, the fuse link 52 is fused, and the resistor 523 is connected into the circuit, so that the discharging current in the circuit is reduced, and the thermal runaway of the battery caused by overlarge current is avoided. Therefore, the preset current value of the fuse link 52 should be selected to be a current value that is indicative of a potential risk of thermal runaway of the battery.

The resistor 523 is in a column shape and has a hollow cavity 53, the fuse link 52 is located in the cavity 53, the insulation-conductive transition body 510 includes a first division 521 and a second division 522, and the first division 521 and the second division 522 are located on both sides of the cavity 53 and are in contact with the fuse link 52 in the cavity 53. Further, the resistor 523 further has a first mounting groove 511 and a second mounting groove 512, the first mounting groove 511 and the second mounting groove 512 are located at both sides of the cavity 53, and a portion of the first division 521 is embedded in the first mounting groove 511 and a portion of the second division 522 is embedded in the second mounting groove 512. The structure of the composite safety assembly 500 thus designed facilitates the assembly of the composite safety assembly 500 itself, and facilitates the assembly of the composite safety assembly 500 within the battery cover plate assembly 400. In addition, the upper surface of the first component 521 is designed to protrude from the upper surface of the resistor 523, and the lower surface of the second component 522 is designed to protrude from the lower surface of the resistor 523, so that the composite safety component 500 can be conveniently connected in series between the upper surface of the conductive component 410 and the negative electrode terminal 422.

In some embodiments, first and

second components

521, 522 may be sheet-like, block-like, film-like. The depth of the first and second mounting

grooves

511 and 512 is half the thickness of the insulation-conductive transition body 510. The first and

second members

521, 522 may have the same or different shapes, and for example, the first member 521 is a sheet and the second member 522 is a block.

Illustratively, the resistance value of the resistor body 523 is larger than that in the case where the fuse link 52 does not exceed a preset current value. In some embodiments, the resistance of the resistor 523 is much greater than the resistance of the fuse link 52 when the fuse link 52 is not blown, and the resistance of the fuse link 52 is small enough to be negligible relative to the resistance of the resistor 523, so that current flows mainly through the fuse link 52 without exceeding a predetermined current value. In contrast, when the fuse link 52 is blown, referring to fig. 6, the fuse link 52 connected in parallel with the resistor 523 in fig. 6 is opened, and the current increases from the equivalent resistance value of the resistor 523 to the composite safety component 500, and the current flowing through the composite safety component 500 is reduced.

Illustratively, the resistance value of the resistor 523 is between 10m Ω and 10k Ω, the material of the fuse link 52 includes one or more of copper, aluminum, nickel, iron, and tin, and the preset current value (i.e., the fusing current value) is between 500A and 5000A. For example, in one embodiment, the fuse link 52 is aluminum and the fuse current value ranges from 1000A to 1500A.

In addition to the ranges defined by the fuse link 52 and the resistor 523, the resistance of the resistor 523, the fusing current and the fusing rate of the fuse link 52 may be selected differently according to the capacities of different battery cells 100. For example, the fuse link 52 may be any one of a fuse rate selection T-shape (Time-lag, for slow fusing), F-type (Fast, for Fast fusing), and M-type (Mediumtime-lag, for medium speed). Referring to fig. 2 and 6, in some embodiments, when the temperature of the battery using the battery cover plate assembly is normal (i.e., the temperature does not exceed a preset temperature threshold), the insulation-conductive transition body 510 in the composite safety assembly 500 is an insulator, and the negative terminal 422 and the conductive member 410 are not in conduction. When the battery charging temperature using the battery cover plate assembly is normal, the insulation-conductive transition body 510 in the composite safety assembly 500 does not undergo a phase transition, which is an insulator, and conduction between the negative terminal 422 and the conductive member 410 is not established. When overcharge occurs, heat is generated inside the battery, and the temperature of the insulation-conduction transformation body 510 in the composite safety assembly 500 reaches 68 ℃ under the action of joule heat of the negative pole column 452, the insulation-conduction transformation body 510 is subjected to phase transformation within 1 second, the composite safety assembly 500 becomes a conductor, the negative pole terminal 422 and the conductive piece 410 are conducted through the composite safety assembly 500, an external short circuit is formed, the internal energy of the battery is released in time, and the charging state of the battery is reduced. Meanwhile, as the short-circuit discharge progresses, the temperature of the negative pole column 452 further rises, when the fuse link 52 in the composite safety assembly 500 reaches the fusing condition, the fuse link 52 is fused, the resistor 523 is connected into the circuit, the composite safety assembly 500 maintains conduction between the negative pole terminal 422 and the conductive piece 410 through the resistor 523 and the insulation-conductive transition body 510, the battery is continuously discharged at a small current, the power battery is prevented from thermal runaway, therefore, the overheating protection of the battery is realized, and the safety of the battery during charging is improved.

The utility model discloses a have a point that, through series connection access composite safety subassembly between negative terminal or positive terminal and electrically conductive piece, composite safety subassembly has the resistive element, fuse-link and insulating-electrically conductive transformation body, and the fuse-link is the fuse that can overflow fusing metal, resistive element and fuse-link parallel connection, insulating-electrically conductive transformation body and parallel connection's resistive element and fuse-link series connection. The composite safety assembly is changed into a conductor when the battery is overheated to reach the transition temperature of the insulation-conduction transformation body, the battery forms a short-circuit state through the insulation-conduction transformation body and the fuse body, heavy current discharge is carried out, the residual capacity of the battery is rapidly reduced in the initial stage of short circuit, when the discharge current continuously increases and exceeds the preset current value of the fuse body, the fuse body fuses, the resistor body is connected into a circuit, the battery maintains the short-circuit state through the insulation-conduction transformation body and a resistor body channel, the battery is continuously discharged at a low current, and step discharge of the battery can be achieved.

The utility model also provides an electric equipment, electric equipment includes the battery of above-mentioned arbitrary embodiment.

The above examples only represent some embodiments of the present invention, and the description thereof is more specific and detailed, but not to be construed as limiting the scope of the present invention. It should be noted that, for those skilled in the art, without departing from the concept of the present invention, several variations and modifications can be made, which all fall within the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the appended claims.

Claims

1. A battery cover plate component is characterized by comprising a positive terminal (421), a negative terminal (422), a conductive component (410) and a composite safety component (500);

the positive terminal (421) is electrically connected with the conductive piece (410), and the negative terminal (422) is electrically connected with the conductive piece (410) through the composite safety component (500);

the composite safety assembly (500) comprises a resistor body (523), a fuse link (52) and an insulation-conduction transition body (510), wherein the resistor body (523) is connected with the fuse link (52) in parallel, and the insulation-conduction transition body (510) is connected with the resistor body (523) and the fuse link (52) connected in parallel in series;

the insulation-conduction transition body (510) is an insulator when the temperature does not exceed a preset temperature threshold value, and is an electric conductor when the temperature exceeds the preset temperature threshold value; the fuse link (52) is an electric conductor when the current does not exceed a preset current value, and fuses when the current exceeds the preset current value.

2. The battery cover plate assembly according to claim 1, wherein the resistor body (523) has a cavity (53), the fuse link (52) is located in the cavity (53), and the insulation-conductive transition body (510) includes a first division body (521) and a second division body (522), and the first division body (521) and the second division body (522) are electrically connected to the fuse link (52) in the cavity (53), respectively.

3. The battery cover plate assembly of claim 2, wherein the resistor body (523) further has a first mounting groove (511) and a second mounting groove (512), the first mounting groove (511) and the second mounting groove (512) are located at upper and lower sides of the cavity (53), and a portion of the first division body (521) is inserted into the first mounting groove (511) and a portion of the second division body (522) is inserted into the second mounting groove (512).

4. The battery cover plate assembly according to claim 1, further comprising an insulating gasket (430), wherein the insulating gasket (430) is disposed between the negative terminal (422) and the conductive member (410), an accommodating hole (432) is formed in the insulating gasket (430), and the composite safety assembly (500) is located in the accommodating hole (432).

5. The battery cover plate assembly according to any one of claims 1 to 3, further comprising a bracket (440), the bracket (440) being disposed at a bottom of the conductive member (410) for supporting the conductive member (410).

6. The battery cover plate assembly according to claim 1, wherein the resistance value of the resistor body (523) is larger than that when the fuse link (52) is a conductive body.

7. The battery cover plate assembly according to claim 1, wherein the predetermined temperature threshold of the insulating-conducting transition body (510) is between 40 ℃ and 70 ℃.

8. The battery cover plate assembly of claim 1, wherein the predetermined current value is between 500A and 5000A.

9. A battery comprising a battery cell (100), a casing (300), and a battery cover assembly according to any one of claims 1 to 8, wherein the battery cell (100) is located in the casing (300), and the casing (300) has an opening, and the battery cover assembly is covered on the opening.

10. An electrical consumer, characterized in that the consumer comprises a battery according to claim 9.