CN215771432U

CN215771432U - Explosion-proof lithium battery

Info

Publication number: CN215771432U
Application number: CN202121853711.5U
Authority: CN
Inventors: 王君
Original assignee: Ningbo Keliter Battery Accessories Co ltd
Current assignee: Ningbo Keliter Battery Accessories Co ltd
Priority date: 2021-08-09
Filing date: 2021-08-09
Publication date: 2022-02-08
Anticipated expiration: 2031-08-09

Abstract

The application discloses an explosion-proof lithium battery, which comprises a lithium battery shell, a top cap component and a bottom cap component, wherein the top cap component and the bottom cap component are respectively arranged at the upper end and the lower end of the lithium battery shell, the top cap component is provided with a first explosion-proof part, the bottom cap component is provided with a second explosion-proof part, when the internal pressure of the lithium battery shell is overlarge, the first explosion-proof part and the second explosion-proof part are in a disconnected state, the upper end and the lower end of the lithium battery shell are respectively subjected to explosion-proof operation through the first explosion-proof part and the second explosion-proof part, the double-layer explosion-proof structure is adopted to greatly enhance the explosion-proof performance of the lithium battery, the safety of the lithium battery is improved, one end, close to the bottom cap assembly, of the lithium battery shell is provided with a liquid injection hole, the liquid injection hole is arranged in the middle of the lithium battery shell, the impregnation speed between injected electrolyte and an electric core is greatly improved, the impregnation time between the electrolyte and the electric core is effectively reduced, and the impregnation efficiency is improved.

Description

Explosion-proof lithium battery

Technical Field

The application relates to the technical field of batteries, in particular to an explosion-proof lithium battery.

Background

A lithium battery is a type of battery using a nonaqueous electrolyte solution, using lithium metal or a lithium alloy as a positive/negative electrode material. When the lithium battery is used and the battery overshoots or has other faults due to improper operation, a large amount of gas is generated in the lithium battery due to chemical reaction, so that the internal pressure of the battery is rapidly increased, explosion is easy to occur, and the user is injured; in addition, it is generally from the side to annotating liquid in the lithium cell when carrying out electrolyte and annotating liquid, and the electrolyte of pouring into afterwards can absorb to electric core, because it is from adopting the mode of annotating liquid from the side, leads to electrolyte impregnation process consuming time longer, greatly increased lithium cell manufacturing cost like this.

SUMMERY OF THE UTILITY MODEL

In order to overcome prior art's not enough, an aim at of this application provides an explosion-proof lithium cell, through the dual explosion-proof structure that sets up first explosion-proof portion and the explosion-proof portion of second, be convenient for effectively carry out the pressure release operation from lithium cell casing's upper and lower both ends fast, improve its explosion-proof performance, through will annotating the liquid hole and set up in the middle part of lithium cell casing's lower extreme, be convenient for shorten the flooding time between electrolyte and the electric core, improve flooding efficiency.

In order to achieve the above purposes, the technical scheme adopted by the application is as follows: the utility model provides an explosion-proof lithium battery, includes lithium cell casing, top cap subassembly and end cap subassembly, top cap subassembly with end cap subassembly branch is located lithium cell casing's upper and lower both ends, top cap subassembly is equipped with first explosion-proof portion, end cap subassembly is equipped with the explosion-proof portion of second, when pressing too big in lithium cell casing, first explosion-proof portion and the explosion-proof portion of second is in the off-state, be close to on the lithium cell casing the one end of end cap subassembly is equipped with annotates the liquid hole, annotate the liquid hole set up in lithium cell casing's centre.

Further, the top cap assembly comprises a positive plate, a first cap and a first sealing ring, the first cap is arranged at the upper end of the positive plate, the first sealing ring is arranged at the lower end of the first cap and sleeved on the outer surface of the positive plate, the first explosion-proof portion is arranged on the first sealing ring, and an explosion-proof buffer area is arranged between the first sealing ring and the first cap.

Further, positive plate includes installation section and linkage segment, the linkage segment rigid coupling in the installation section, the linkage segment weld in lithium cell casing is last, be equipped with first mounting hole on the first sealing washer, be equipped with the second mounting hole on the first cap, first mounting hole and second mounting hole and butt in anodal utmost point post are passed in proper order to the linkage segment.

Further, first sealing washer includes installation department, arc buffering portion and joint portion, the one end of arc buffering portion is connected the installation department, the other end of arc buffering portion is connected joint portion, first explosion-proof portion set up in the installation department, first explosion-proof portion is followed integratively the lower surface of first sealing washer to the sunken formation of explosion-proof buffer area direction.

Further, the first explosion-proof part is V-shaped or trapezoidal.

Further, joint portion includes first horizontal section and first vertical section, first vertical section rigid coupling in keep away from on the first horizontal section one side of arc buffering portion, first horizontal section and first vertical section can form the L shape structure joint portion.

Further, the bottom cap assembly further comprises a second cap cover, the second explosion-proof portion is arranged on the second cap cover, and the second explosion-proof portion is integrally formed by upwards sinking from the lower end of the second cap cover.

Further, the second explosion-proof part is V-shaped or trapezoidal.

Further, be equipped with first canned paragraph and second canned paragraph on the lithium cell casing, the second canned paragraph is followed integratively first canned paragraph is sunken formation upwards, first stiff end and can enclose into the mounting groove between the second canned paragraph, the second cap install in the mounting groove.

Further, annotate the liquid hole set up in the centre of second fixed section, the one end intercommunication of annotating the liquid hole the mounting groove, the other end intercommunication of annotating the liquid hole the inside of lithium cell casing.

Compared with the prior art, the beneficial effect of this application lies in:

(1) the lithium battery shell is provided with a first explosion-proof part and a second explosion-proof part, and the upper end and the lower end of the lithium battery shell can be respectively subjected to explosion-proof operation through the first explosion-proof part and the second explosion-proof part, so that the explosion-proof performance of the lithium battery shell is greatly enhanced, and the safety of the lithium battery is improved.

(2) It is equipped with annotates the liquid hole, annotates the liquid hole and sets up in the centre of lithium cell casing lower extreme, is convenient for annotate liquid through annotating the liquid hole to lithium cell inside from the centre for in the infiltration electric core that electrolyte can be rapid, improve the flooding speed between the electrolyte of pouring into and the electric core greatly, reduce the flooding time between electrolyte and the electric core effectively, improve flooding efficiency.

Drawings

Fig. 1 is a schematic structural diagram of a lithium battery in the present application.

Fig. 2 is a schematic structural diagram of a lithium battery provided with first sealing rings of different structures.

Fig. 3 is an exploded view of a lithium battery according to the present application.

Fig. 4 is a top view of a first seal ring of the present application.

Fig. 5 is a cross-sectional view taken along a-a of fig. 4 of the present application.

Fig. 6 is a top view of the elongated structure of the protrusions on the connecting plate in the present application.

FIG. 7 is a cross-sectional view taken along line B-B of FIG. 6 of the present application.

FIG. 8 is a top view of a plurality of inclined plate structures of the protrusions on the connecting plate in the present application.

FIG. 9 is a cross-sectional view taken along line C-C of FIG. 8 of the present application.

FIG. 10 is a schematic view of the top cap assembly and the connecting piece of the present application in connection.

FIG. 11 is a schematic structural view of the top cap assembly of the present application.

In the figure: 1. a lithium battery; 10. a lithium battery case; 11. a first fixed section; 12. a second fixed section; 121. a liquid injection hole; 13. mounting grooves; 20. connecting sheets; 21. a connecting sheet body; 211. a through hole; 212. an exhaust hole; 213. a first exhaust port; 214. a second vent hole; 22. a protrusion; 221. a first protrusion; 222. a second protrusion; 30. a top cap assembly; 31. a first explosion-proof portion; 32. a positive plate; 321. an installation section; 322. a connecting section; 33. a first cap; 331. a second mounting hole; 34. a first seal ring; 341. a first mounting hole; 342. an installation part; 343. a connecting portion; 344. a clamping part; 345. a first transverse segment; 346. a first vertical section; 35. an explosion-proof buffer zone; 40. a bottom cap assembly; 41. a second explosion-proof part; 42. a second cap.

Detailed Description

The present application is further described below with reference to specific embodiments, and it should be noted that, without conflict, any combination between the embodiments or technical features described below may form a new embodiment.

In the description of the present application, it should be noted that, for the terms of orientation, such as "central", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., it indicates that the orientation and positional relationship shown in the drawings are based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, but does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be construed as limiting the specific scope of protection of the present application.

It is noted that the terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order.

The terms "comprises," "comprising," and "having," and any variations thereof, in the description and claims of this application, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

A lithium battery 1 as shown in fig. 1-11, which comprises a lithium battery case 10, a connecting piece 20, a top cap assembly 30 and a bottom cap assembly 40, wherein the connecting piece 20 is disposed at the upper and lower ends of the lithium battery case 10, the connecting piece 20 at the upper end connects the lithium battery case 10 and the top cap assembly 30, the top cap assembly 30 and the connecting piece 20 can be connected by resistance welding, the connecting piece 20 at the lower end connects the lithium battery case 10 and the bottom cap assembly 40, the bottom cap assembly 40 and the connecting piece 20 can be connected by arc welding, and a battery core composed of an anode, a cathode, a diaphragm and electrolyte of the battery is disposed in the lithium battery case 10, thereby assembling a completed lithium battery 1. Top cap subassembly 30 is equipped with first explosion-proof part 31, first explosion-proof part 31 can carry out the pressure release to lithium cell 1 upper end, end cap subassembly 40 is equipped with the explosion-proof part 41 of second, the explosion-proof part 41 of second can carry out the pressure release to lithium cell 1's bottom, press when too big in lithium cell casing 10, first explosion-proof part 31 and the explosion-proof part 41 of second can fracture, can carry out the pressure release operation to lithium cell casing 10's both ends through first explosion-proof part 31 and the explosion-proof part 41 of second, can improve its pressure release capacity, increase multiple explosion-proof insurance, avoid its explosion effectively, improve its safety in utilization.

As shown in fig. 1, 10 and 11, the top cap assembly 30 includes a positive electrode tab 32 and a first cap 33, the positive electrode tab 32 is disposed at the upper end of the connecting piece 20, the bottom of the positive electrode tab 32 is welded to the connecting piece 20 by resistance welding, and the upper end of the positive electrode tab 32 sequentially passes through a first sealing ring 34 and the first cap 33 to abut on the positive electrode post. First cap 33 sets up in the upper end of positive plate 32, and first cap 33 can carry out the closed function to the battery positive terminal, avoids its inside electrolyte to permeate the external world, plays the guard action to lithium cell 1, is equipped with first sealing washer 34 between first cap 33 and the connection piece 20, and the outside of positive plate 32 is located to first sealing washer 34 cover, and first sealing washer 34 can play sealed operation to between connection piece 20 and the first cap 33, improves whole lithium cell 1's sealing performance.

As shown in fig. 3, the positive electrode tab 32 includes an installation section 321 and a connection section 322, the connection section 322 is fixedly connected to the installation section 321 to form the positive electrode tab 32 with an inverted T-shaped structure, and the installation section 321 and the connection sheet 20 are connected by resistance welding, where resistance welding is a method of using a strong current to pass through a contact point between a motor and a workpiece and using contact resistance to generate heat to achieve welding. The first sealing ring 34 is provided with a first mounting hole 341, the first cap 33 is provided with a second mounting hole 331, and the connecting section 322 sequentially passes through the first mounting hole 341 and the second mounting hole 331 and abuts against the positive pole, so that electric energy in the lithium battery shell 10 can be conveyed outwards through the positive plate 32 and the positive pole, and power supply operation is realized.

As shown in fig. 3 and 5, the first explosion-proof portion 31 is disposed on the first sealing ring 34, an explosion-proof buffer area 35 is disposed between the first sealing ring 34 and the first cap 33, the explosion-proof buffer area 35 facilitates an excessive pressure inside the lithium battery case 10, and the first sealing ring 34 is torn off from the first explosion-proof portion 31, so that the first explosion-proof portion 31 does not receive an upper pressure when the first explosion-proof portion 31 is broken, and thus the gas inside the lithium battery case 10 can be released, and through a synergistic effect of the first explosion-proof portion 31 and the explosion-proof buffer area 35, the pressure inside the lithium battery case 10 can be effectively relieved, thereby preventing the explosion caused by the excessive pressure. The first cap 33 is provided with an exhaust port communicated with the explosion-proof buffer area 35, so that gas released in the lithium battery shell 10 is conveniently exhausted from the exhaust port through the first explosion-proof part 31 and the explosion-proof buffer area 35, and the purpose of pressure relief is achieved.

As shown in fig. 3-5, the first sealing ring 34 includes an installation portion 342, a connection portion 343, and a clamping portion 344, the installation portion 342 is connected to one end of the connection portion 343, the clamping portion 344 is connected to the other end of the connection portion 343, when the connection portion 343 is normally sealed by the first sealing ring 34, an extrusion force toward the lithium battery pack 10 is generated to the clamping portion 344, so that the clamping portion 344 can be firmly abutted against the inside of the lithium battery pack 10, thereby achieving a good sealing operation, and when the connection portion 343 is also capable of ensuring that the internal pressure of the lithium battery pack 10 is too high, the first explosion-proof portion 31 is conveniently broken due to the arc-shaped structure, thereby increasing the pressure relief speed thereof. The first mounting hole 341 is disposed on the mounting portion 342, the mounting portion 342 is sleeved on the outer surface of the connecting portion 322 through the first mounting hole 341, and the clamping portion 344 abuts against the inner side of the lithium battery casing 10, so that the first sealing ring 34 seals the inside of the lithium battery casing 10, and the sealing performance of the lithium battery casing 10 is improved. First explosion-proof portion 31 sets up in installation department 342, and first explosion-proof portion 31 is sunken to form to explosion-proof buffer 35 direction from the lower surface of first sealing washer 34 integratively, because the thickness of first explosion-proof portion 31 is thinner, be convenient for when lithium cell casing 10 internal pressure is too big, first explosion-proof portion 31 department can be torn fast, can release by the gas in lithium cell casing 10, thereby reach the purpose of pressure release, avoid it to explode, improve lithium cell 1's life.

As shown in fig. 3 to 5, the connecting portion 343 has an arc-shaped structure, the connecting portion 343 has an arc-shaped connecting portion 342 and a clamping portion 344, and the connecting portion 343 has an arc-shaped structure similar to a reinforcing rib, so as to enhance the strength of the first sealing ring 34.

As shown in fig. 4 and 5, the clamping portion 344 includes a first transverse section 345 and a first vertical section 346, the first vertical section 346 is fixed on a side of the first transverse section 345 away from the connecting portion 343, and the first transverse section 345 and the first vertical section 346 form the clamping portion 344 with an L-shaped structure. When the first sealing ring 34 is installed, the first installation hole 341 is aligned with the positive plate 32, so that the installation part 342 can be sleeved on the positive plate 32, and meanwhile, the first vertical section 346 can be abutted against the inner side of the lithium battery shell 10, so that under the action of the clamping part 344 of the L-shaped structure, the first sealing ring 34 can be firmly clamped above the connecting piece 20, and the first sealing ring 34 can seal the lithium battery shell 10 and the outside.

The height of the connecting section 322 is greater than that of the first vertical section 346, so that when the upper end of the connecting section 322 abuts against the positive pole, the first vertical section 346 does not interfere with the connection between the lithium battery 1 and other elements.

As shown in FIG. 4, the first vertical section 346 has a height of 3.8mm to 5.2mm, and the connecting section 322 has a height of 5.5mm to 6.8 mm.

As shown in FIG. 4, the height of the first vertical section 346 is 4.4mm, and the height of the connecting section 322 is 5.8 mm.

As shown in fig. 2-3, the bottom cap assembly 40 further includes a second cap 42, the second explosion-proof portion 41 is disposed on the second cap 42, the second explosion-proof portion 41 is integrally formed by upward sinking from the lower end of the second cap 42, when the internal pressure of the lithium battery case 10 is too high, the second explosion-proof portion 41 can be broken, so that the gas inside the lithium battery case 10 is released from the lower end, and by disposing the first explosion-proof portion 31 and the second explosion-proof portion 41, the pressure inside the lithium battery case 10 can be simultaneously released from the upper and lower ends of the lithium battery case 10, so as to increase the pressure release speed, avoid explosion, and effectively ensure the safety during the use process.

As shown in fig. 3, the first explosion-proof part 31 and the second explosion-proof part 41 are both V-shaped or trapezoidal, the thickness of the first explosion-proof part 31 is much smaller than that of the first sealing ring 34, and the thickness of the second explosion-proof part 41 is much smaller than that of the second cap 42, when the internal pressure of the lithium battery case 10 is too high, the upper end of the lithium battery case 10 can release the gas inside the lithium battery case through the broken first explosion-proof part 31 because the thicknesses of the first explosion-proof part 31 and the second explosion-proof part 41 are thin, the lower end of the lithium battery case can release the gas inside the lithium battery case through the broken second explosion-proof part 41, and the gas inside the lithium battery case 10 is released through the upper end and the lower end, so that the release speed of the gas is increased, and the safety of the lithium battery case in the using process is effectively guaranteed.

As shown in fig. 3, a first fixing section 11 and a second fixing section 12 are arranged on the lithium battery case 10, the second fixing section 12 is integrally formed by upward sinking from the first fixing section 11, the second fixing section 12 is welded to the connecting piece 20, the second fixing section 12 and the connecting piece 20 are connected in an arc welding manner, a mounting groove 13 is formed between the first fixing section 11 and the second fixing section 12 in a surrounding manner, and a second cap 42 is mounted in the mounting groove 13, so that the bottom of the lithium battery case 10 is sealed, and the sealing performance of the whole lithium battery 1 is improved.

As shown in fig. 1 to 3, a liquid injection hole 121 is formed in the second fixed segment 12, the liquid injection hole 121 is formed in the middle of the second fixed segment 12, one end of the liquid injection hole 121 is communicated with the mounting groove 13, the other end of the liquid injection hole 121 is communicated with the inside of the lithium battery shell 10, the purpose of the liquid injection hole 121 is to effectively replace the side edge to middle injection of electrolyte in the prior art, so that the liquid injection speed of the lithium battery can be greatly improved, meanwhile, the electrolyte can be injected from the middle, so that the battery cell can be uniformly and rapidly impregnated with the electrolyte, for the operation of injecting the electrolyte from the side edge, the impregnation time of two thirds can be effectively shortened, and the production efficiency of the lithium battery 1 is greatly improved.

As shown in fig. 6 to 9, the connecting sheet 20 includes a connecting sheet body 21 and a plurality of protrusions 22, the plurality of protrusions 22 are separately disposed on the connecting sheet body 21 at intervals, and the plurality of protrusions 22 are disposed to effectively enable a welding manner of point-surface-to-surface contact to be adopted between the connecting sheet 20 and the lithium battery 1, so as to effectively replace surface-to-surface contact in the prior art, thereby improving the welding accuracy of the connecting sheet 20 and preventing the occurrence of cold joint.

As shown in fig. 6 and 8, the connecting sheet body 21 is provided with a through hole 211 and an exhaust hole 212, the through hole 211 is disposed in the middle of the connecting sheet body 21, the through hole 211 is aligned with the electrolyte injection hole 121, when electrolyte is injected, the second cap 42 is not welded in the mounting groove 13, therefore, an operator can inject electrolyte into the lithium battery case 10 through the electrolyte injection hole 121 and the through hole 211, after the deposition of electrolyte in the lithium battery case 10 is completed, the second cap 42 is welded in the mounting groove 13, so that the second cap 42 is welded by the deposition of electrolyte, and the sealing performance inside the lithium battery case 10 is ensured. Exhaust hole 212 is the circumference along through-hole 211 all around and distributes, and arch 22 sets up on connection piece body 21 with exhaust hole 212 is crisscross, and exhaust hole 212 can get rid of lithium cell 1 inside gas, reaches the purpose of carrying out the pressure release and cooling to it, can also alleviate lithium cell 1's weight simultaneously greatly, promotes lithium cell 1 energy density, also can reduce the resistance that produces when annotating liquid effectively simultaneously for its annotates liquid speed.

As shown in fig. 6 to 7, in some embodiments, the protrusion 22 is a long strip structure, which facilitates the integrity of the welding, so that the welding points at the welding feet on the connecting sheet 20 are all located on the same plane, thereby effectively solving the problem in the prior art that the welded electrode surfaces are not located on the same plane due to the powder on the surface of the negative electrode, effectively avoiding the occurrence of cold welding, and thus ensuring good conductivity of the lithium battery 1.

As shown in fig. 8-9, in some embodiments, the protrusion 22 may also be formed by combining a plurality of inclined plates, the plurality of inclined plates are distributed along the radial direction of the connecting sheet body 21, each inclined plate integrally extends downward from the connecting sheet body 21 to form an interrupted welding seam, so that the total heat input amount during welding is greatly reduced, and meanwhile, the plurality of inclined plates arranged at intervals can not only ensure the welding firmness, but also avoid the uneven condition of the surface of the connecting sheet 20 after welding caused by the intersection of the welding seams between two adjacent inclined plates during welding, thereby improving the welding integrity of the whole connecting sheet 20.

As shown in fig. 6 to 9, the protrusion 22 includes a first protrusion 221 and a second protrusion 222, the first protrusion 221 is circumferentially distributed on the connecting sheet body 21, the second protrusion 222 is circumferentially distributed on the connecting sheet body 21, the first protrusion 221 and the second protrusion 222 are alternately arranged on the connecting sheet body 21, a second protrusion 222 is arranged between two adjacent first protrusions 221, and under the synergistic effect of the first protrusion 221 and the second protrusion 222, the welding accuracy of the connecting sheet body 21 is greatly improved, and the occurrence of cold joint is prevented.

As shown in fig. 6 to 9, the length of the first protrusion 221 is greater than that of the second protrusion 222, and the first protrusion 221 and the second protrusion 222 are arranged in a staggered manner, so that the welding firmness is improved, and the problem that the conductivity of the lithium battery 1 is poor due to the infirm welding is avoided.

As shown in fig. 6 to 9, the vent hole 212 includes a first vent hole 213 and a second vent hole 214, the first vent hole 213 is circumferentially distributed on the connecting sheet body 21, the second vent hole 214 is circumferentially distributed on the connecting sheet body 21, the first vent hole 213 and the second vent hole 214 are alternately disposed on the connecting sheet body 21, a second vent hole 214 is disposed between every two adjacent first vent holes 213, and the arrangement of the plurality of first vent holes 213 and the plurality of second vent holes 214 can greatly increase the exhaust speed of the lithium battery 1, so that the internal air pressure thereof does not rise, and the safety of the battery during operation is improved.

As shown in fig. 6 to 9, the first exhaust hole 213 is disposed at a side close to the through hole 211, the diameter of the first exhaust hole 213 is smaller than that of the second exhaust hole 214, and the first exhaust hole 213 and the second exhaust hole 214 having different diameters are disposed, so that each part inside the lithium battery 1 can be effectively exhausted, the stability of the lithium battery 1 is improved, and explosion of the lithium battery is avoided.

Wherein, in some embodiments, the height of the first vertical section 346 may be 3.8mm, 3.9mm, 4.0mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, 5.0mm, 5.1mm, 5.2mm, and the height of the first vertical section 346 may vary accordingly according to different battery specification requirements, but the height of the first vertical section 346 may not be limited to the above values.

Wherein, in some embodiments, the height of the connecting section 322 may be 5.5mm, 5.6mm, 5.7mm, 5.8mm, 5.9mm, 6.0mm, 6.1mm, 6.2mm, 6.3mm, 6.4mm, 6.5mm, 6.6mm, 6.7mm, 6.8mm, and the height of the connecting section 322 may be varied according to different battery specification requirements, but the height of the connecting section 322 may not be limited to the above values.

In some embodiments, the protrusions 22 may be, but are not limited to, 2, 3, 4, or 5, which facilitates air leakage in all phases and increases safety of use.

In some embodiments, the structure of the lithium battery 1 may be cylindrical, square column, oval, etc., and correspondingly, the top cap assembly 30, the connecting piece 20, and the bottom cap assembly 40 may also be cylindrical, square column, or oval.

The prepared lithium battery 1 and the common lithium battery are respectively subjected to an expansion test, when the internal voltage of the battery is 1.3 MPa-1.5 MPa, the common lithium battery starts to bulge, and the lithium battery 1 prepared by the method is intact; when the internal pressure of the battery is 1.5MPa to 1.7MPa, the second cap 42 of the lithium battery 1 prepared by the method is broken, the first cap 33 is intact, and the reason why the second cap 42 is broken is that the second cap 42 is broken before the first cap 33 when receiving pressure because the second cap 42 is thinner; when the internal pressure of the battery is 1.7-1.9 MPa, the second cap 42 and the first cap 33 of the lithium battery 1 prepared by the method are both broken; when the internal pressure of the battery exceeds 1.9MPa, the lithium battery 1 prepared by the method explodes.

The foregoing has described the general principles, essential features, and advantages of the application. It will be understood by those skilled in the art that the present application is not limited to the embodiments described above, which are merely illustrative of the principles of the application, but that various changes and modifications may be made without departing from the spirit and scope of the application, and these changes and modifications are intended to be within the scope of the application as claimed. The scope of protection claimed by this application is defined by the following claims and their equivalents.

Claims

1. An explosion-proof lithium battery, characterized in that: including lithium cell casing, top cap subassembly and end cap subassembly, top cap subassembly with end cap subassembly branch is located lithium cell casing's upper and lower both ends, top cap subassembly is equipped with first explosion-proof portion, end cap subassembly is equipped with the explosion-proof portion of second, when the pressure is too big in lithium cell casing, first explosion-proof portion and the explosion-proof portion of second is in the off-state, be close to on the lithium cell casing the one end of end cap subassembly is equipped with annotates the liquid hole, annotate the liquid hole set up in lithium cell casing's centre.

2. The explosion-proof lithium battery of claim 1, wherein: the top cap component comprises a positive plate, a first cap and a first sealing ring, the first cap is arranged at the upper end of the positive plate, the first sealing ring is arranged at the lower end of the first cap and sleeved on the outer surface of the positive plate, the first explosion-proof part is arranged on the first sealing ring, and an explosion-proof buffer area is arranged between the first sealing ring and the first cap.

3. The explosion-proof lithium battery of claim 2, wherein: first sealing washer includes installation department, arc buffering portion and joint portion, the one end of arc buffering portion is connected the installation department, the other end of arc buffering portion is connected joint portion, first explosion-proof portion set up in the installation department, first explosion-proof portion is followed integratively the lower surface of first sealing washer to the sunken formation of explosion-proof buffer area direction.

4. An explosion-proof lithium battery as claimed in claim 3, characterized in that: the first explosion-proof part is V-shaped or trapezoidal.

5. The explosion-proof lithium battery of claim 4, wherein: the joint portion includes first horizontal section and first vertical section, first vertical section rigid coupling in keep away from on the first horizontal section one side of arc buffering portion, first horizontal section and first vertical section can form the L shape structure joint portion.

6. The explosion-proof lithium battery of claim 1, wherein: the bottom cap assembly further comprises a second cap cover, the second explosion-proof portion is arranged on the second cap cover, and the second explosion-proof portion is integrally formed by upwards sinking from the lower end of the second cap cover.

7. The explosion-proof lithium battery of claim 6, wherein: the second explosion-proof part is V-shaped or trapezoidal.

8. The explosion-proof lithium battery of claim 7, wherein: be equipped with first canned paragraph and second canned paragraph on the lithium cell casing, the second canned paragraph is followed integratively first canned paragraph is sunken formation upwards, first stiff end and can enclose into the mounting groove between the second canned paragraph, the second cap install in the mounting groove.

9. The explosion-proof lithium battery of claim 8, wherein: the liquid injection hole is formed in the middle of the second fixing section, one end of the liquid injection hole is communicated with the mounting groove, and the other end of the liquid injection hole is communicated with the inside of the lithium battery shell.

10. The explosion-proof lithium battery of claim 2, wherein: the positive plate comprises an installation section and a connection section, the connection section is fixedly connected with the installation section, the connection section is welded on the lithium battery shell, a first installation hole is formed in the first sealing ring, a second installation hole is formed in the first cap, and the connection section penetrates through the first installation hole and the second installation hole and abuts against the positive pole.