Pursuant to 35 U.S.C. § 119 and the Paris Conversion, this application claims priority to Chinese Patent Application No. 202221185440.5 filed May 17, 2022, the entire contents of which are incorporated herein by reference.
The present disclosure relates to the field of battery technology, and more particularly to a battery cell, and a battery having the battery cell.
With the rapid development of new energy vehicles and the practicalization of superfast charging technology, a cooling method of power battery has been upgraded from air cooling to liquid cooling. Furthermore, full immersion oil cooling has also entered the visions of automobile manufacturers. The fully immersed oil cooling is able to bring out the performances of high performance battery cells, prolong service life of the battery cells, and perfectly solve the problems of thermal runaway and failure propagation, and thus has attracted a large number of people's interests due to its extremely high heat exchange efficiency, uniform temperature distribution, and extremely strong passive thermal safety. It is found that steel beads which are most frequently used to be squeezed into the electrolyte injection hole for sealing is of a possibility of steel beads falling out or causing an electrolyte leakage under an extreme temperature condition due to different material expansion rate.
It should be noted that the aforesaid information disclosed in the background is only intended to enhance the interpretation of the background of the present disclosure and thus may include information that does not constitute as prior art known to one of ordinary skill in the art.
One objective of the embodiments of the present disclosure is to provide a battery cell and a battery that aim to solve the technical problem that steel beads which are most frequently used to be squeezed into the electrolyte injection hole for sealing has a possibility of falling out or causing an electrolyte leakage under extreme temperature conditions due to different material expansion rates.
In order to achieve the aforesaid objective, the technical solutions adopted in the present disclosure are as follows: a battery cell is provided, the battery cell includes:
a spiral-wound cell;
a first current collector; the first current collector is connected to one end of the spiral-wound cell, and the first current collector is provided with an electrolyte injection hole; and
a cover plate; the cover plate is connected to the first current collector, and the first current collector is located between the spiral-wound cell and the cover plate, in order that the electrolyte injection hole is sealed by the cover plate.
In some embodiments, one side of the cover plate facing the first current collector is provided with first bursting line(s) which is/are shaped as groove structures.
In some embodiments, the first current collector is provided with an inner side and an outer side which are opposed to each other, the inner side of the first current collector is connected to the spiral-wound cell, and the cover plate is connected to the outer side of the first current collector; the inner side of the first current collector faces the spiral-wound cell, and is provided with a plurality of second bursting lines, and the plurality of second bursting lines are shaped as groove structures.
In some embodiments, the number of the second bursting lines is plural and the plurality of the second bursting lines are arranged to be spaced apart around a circumference of the electrolyte injection hole in distribution.
In some embodiments, the first current collector is arranged at an anode of the spiral-wound cell, the electrolyte injection hole is arranged at a center of the first current collector, the outer side of the first current collector is provided with an accommodation cavity recessed from one end of the spiral-wound cell to the other end of the spiral-wound cell, and the cover plate is fixed in the accommodation cavity.
In some embodiments, a plurality of bypass holes are arranged on the first current collector, and the plurality of the bypass holes are arranged to be spaced apart around the circumference of the electrolyte injection hole in distribution.
In some embodiments, the battery cell further includes a second current collector, the second current collector is connected to an opposite end of the spiral-wound cell, and is arranged at a cathode of the spiral-wound cell.
In some embodiments, the battery cell further includes a housing and a terminal post. The spiral-wound cell is arranged to insert in the housing, the terminal post is fitted to the housing in an insulation manner through a first insulating member.
The terminal post includes a post part and a radial part connected to one end of the post part. The radial part has a diameter greater than a diameter of the post part, so that the terminal post is fixed on the housing. The radial part is connected to the second current collector.
In some embodiments, the battery cell is cylindrical.
In the present disclosure, a battery is further provided, the battery includes the aforesaid battery cell.
The beneficial effects of the battery cell and the battery according to the present disclosure are mainly described as follows:
According to the battery cell of the present disclosure, the first current collector is connected to one end of the spiral-wound cell and the electrolyte injection hole is arranged on the first current collector, electrolyte is injected through the electrolyte injection hole, and the cover plate is connected to the first current collector, and the first current collector is located between the spiral-wound cell and the cover plate. Thus, the electrolyte injection hole is sealed by the cover plate, so that the sealing of the electrolyte injection hole is quite ensured, the possibility of electrolyte leakage is reduced accordingly, and the safety of the battery cell is guaranteed.
In order to describe the embodiments of the present disclosure more clearly, a brief introduction regarding the accompanying drawings that need to be used for describing the embodiments of the present disclosure or the related art is given below; it is obvious that the accompanying drawings described below are merely some embodiments of the present disclosure, a person of ordinary skill in the art may also acquire other drawings according to the current drawings without paying creative labors.
Reference numerals involved in the accompanying figures are listed in detail below:
100—cover plate; 101—spiral—wound cell; 102—first current collector; 103—electrolyte injection hole; 104—first bursting line; 105—second bursting line; 106—accommodation cavity; 107—strip—shaped groove; 108—second current collector; 109—insulating sleeve; 110—housing; 111—terminal post; 112—post part; 113—radical part; 114—end cover; 115—exposed part; 116—axial part; 117—radially convex part; 118—first mounting hole; 119—insulating sheet; 120—second mounting hole; 121—boss part; 122—first insulating member; 123—second insulating member; 124—annular part; 125—axially wrapped part; 126—conductive sheet; 127—insulating ring; 128—notch.
In order to make the technical problem to be solved, the technical solutions and the advantages of the present disclosure be clearer and more understandable, the present disclosure will be further described in detail below with reference to accompanying figures and embodiments. It should be understood that the embodiments described in detail herein are merely intended to illustrate but not to limit the present disclosure.
It needs to be noted that, when one component is described to be “fixed to” or “arranged on” another component, this component may be directly or indirectly arranged on another component. When it is described that one component “is connected with” another component, this component may be directly or indirectly connected to said another component.
In the description of the present disclosure, it needs to be understood that, directions or location relationships indicated by terms such as “length”, “width”, “up”, “down”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, and so on are the directions or location relationships shown in the accompanying figures, which are only intended to describe the present disclosure conveniently and simplify the description, but not to indicate or imply that an indicated device or component must have specific locations or be constructed and manipulated according to specific locations; therefore, these terms shouldn't be considered as any limitation to the present disclosure.
In addition, terms “the first” and “the second” are only used describing purposes, and should not be considered as indicating or implying any relative importance, or implicitly indicating the number of indicated technical features. As such, technical feature(s) restricted by “the first” or “the second” can explicitly or implicitly comprise one or more such technical feature(s). In the description of the present disclosure, “a plurality of” has the meaning of at least two, unless “a plurality of” is provided with additional explicit and specific limitations.
In order to explain the technical solutions of the present disclosure, the present disclosure are described in detail with reference to the accompanying figures and the embodiments below.
Referring to
In some embodiments, the method for sealing the electrolyte injection hole 103 by the cover plate 100 is that orifices of the electrolyte injection hole 103 are sealed by the cover plate 100, or a closed space is formed between the cover plate 100 and the first current collector 102. Since the first current collector 102 is further connected to the spiral-wound cell 101, so that the electrolyte injection hole 103 is not exposed after the first current collector 102 is connected with the cover plate 100, and the appearance of the battery cell is smooth and artistic, and risks of electrolyte leakage and oil seepage are avoided.
In one embodiment, the cover plate 100 and the first current collector 102 are connected by welding. Since the diameters of the cover plate 100 and the first current collector 102 are much greater than that of the conventional steel beads, welded joints having greater diameters can be formed when welding is used, so that a reduction of welding cracks and an improvement of the yield are facilitated. By welding the cover plate 100 with the first current collector 102, a traditional condition of steel beads falling out under extreme temperature due to different material expansion rates is further avoided, and the tightness and the stability of the connection between the cover plate 100 and the first current collector 102 are ensured by welding.
In the present disclosure, the first current collector 102 is connected to one end of the spiral-wound cell 101 by welding, and the electrolyte injection hole 103 is arranged on the first current collector 102, electrolyte is injected through the electrolyte injection hole 103, and the cover plate 100 is used to be connected to the first current collector 102, so that the electrolyte injection hole 103 is blocked by the cover plate 100, the sealing of the electrolyte injection hole 103 is quite ensured. Thus, a possibility of electrolyte leakage is reduced, and the safety of the battery cell is ensured.
Referring to
Referring to
Referring to
In one embodiment, the first current collector 102 is welded with the spiral-wound cell 101. In particular, the first current collector 102 is connected to a tab of the spiral-wound cell 101. The inner side of the cover plate 100 is connected to the outer side of the first current collector 102, the first bursting line(s) 104 is/are located on the inner side of the cover plate 100, and the outer side of the cover plate 100 is exposed. It is worth noting that the first current collector 102 and the spiral-wound cell 101 may be connected directly or indirectly.
In some embodiments, the number of the second bursting lines 105 is plural, and the plurality of second bursting lines 105 are spaced around the circumference of the electrolyte injection hole 103 in distribution. This arrangement facilitates ensuring the safety of the battery cell. Moreover, when bursting occurs, the bursting is prone to occur at the position of the electrolyte injection hole 103.
In some embodiments, one end of each second bursting line 105 is extended to an edge of the electrolyte injection hole 103, that is, one end of an opening of the groove structure in length direction is located on a hole wall of the electrolyte injection hole 103. This arrangement further realizes the bursting occurring more likely at the position of the electrolyte injection hole in case of the occurrence of the bursting, and the safety of the battery cell is ensured during use.
In one embodiment, the second bursting lines 105 are shaped as straight lines, and the plurality of second bursting lines 105 are arranged in a radial pattern which takes the center of the hole of the electrolyte injection hole 103 as the center, that is, each second bursting line 105 has a length direction extended in the radial direction of the first current collector 102.
In some embodiments, the first current collector 102 is arranged at an anode of the spiral-wound cell 101, that is, the first current collector 102 is connected to an anode tab of the spiral-wound cell 101, the electrolyte injection hole 103 is arranged at the middle of the first current collector 102, the outer side of the first current collector 102 is provided with an accommodating cavity 106 recessed from one end of the spiral-wound cell 101 to the other end of the spiral-wound cell 101, and the cover plate 100 is fixed in the accommodating cavity 106. In at least one embodiment, the electrolyte injection hole 103 is arranged at the middle of the first current collector 102, which facilitates simplification of mass production process and enables more accurate alignment with the electrolyte injection hole, and facilitates automatic electrolyte injection and the positioning of negative pressure formation procedure, etc., as compared to other methods of arrangement of the electrolyte injection hole in an offset position.
In one embodiment, the thickness of the cover plate 100 is equal to the depth of the accommodating cavity 106, that is, after the cover plate 100 is fixed in the accommodating cavity 106, the outer side of the cover plate 100 is flush with an outer surface of the first current collector 102, so that one end surface of the anode of the battery cell is flat. The cover plate 100 is welded in the cavity of the current collector 102, so that the battery cell has a smooth appearance. Due to the large diameter welding surface, a problem of stress concentration during welding is avoided, and the improvement of the yield of welding is facilitated. It should be noted that the accommodating cavity 106 can be formed by stamping.
In some embodiments, a bottom of the accommodating cavity 106 of the first current collector 102 has a plurality of strip-shaped recesses 107, and the plurality of strip-shaped recesses 107 are radially distributed, and a length of each strip-shaped recess 107 extends along the radial direction of the first current collector 102. The plurality of strip-shaped recesses 107 are provided at the bottom of the accommodating cavity when viewed from the outer side of the first current collector 102, while the walls and bottoms of the plurality of strip-shaped recesses 107 are protruded from the inner side of the first current collector 102 when viewed from the inner side of the first current collector 102, so that strip-shaped bosses are formed. Each second bursting line 105 is located between two adjacent strip-shaped bosses. It needs to be noted that the strip-shaped recesses 107 may be formed by stamping.
In some other embodiments, a plurality of bypass holes are further provided on the first current collector 102, and the plurality of bypass holes are spaced around the circumference of the electrolyte injection holes 103 in distribution.
In some embodiments, the battery cell further includes a second current collector 108, the second current collector 108 is connected to the opposite end of the spiral-wound cell 101. The second current collector 108 is connected to a tab at the opposite end of the spiral-wound cell 101. The second current collector 108 is arranged at a cathode of the spiral-wound cell 101, in other words, the second current collector 108 is connected to a cathode tab of the spiral-wound cell 101.
In some embodiments, the outer side of the second current collector 108 has a plurality of strip-shaped recesses 107, the plurality of strip-shaped recesses 107 are radially distributed, and the length of each strip-shaped recess 107 is extended along the radial direction of the second current collector 108. The plurality of strip-shaped recesses 107 are observed from the outer side of the second current collector 108, while the walls and the bottoms of the plurality of strip-shaped recesses 107 are protruded from the inner side of the second current collector 108 when viewed from the inner side of the second current collector 108, so that the strip-shaped bosses are formed. A circumferential edge of the second current collector 108 is further provided with a plurality of notches 128, so that the second current collector 108 becomes a deformable and elastic structure that allows a small displacement of the spiral-wound cell 101 in an axial direction without damaging the welded areas between the second current collector 108 and the spiral-wound cell 101, and the welded areas between the first current collector 102 and the spiral-wound cell 101, respectively. It should be noted that in some other embodiments, the second current collector 108 can also be shaped as deformable and elastic structure in other forms.
In one embodiment, the first current collector 102 serves as the current collector at the anode of the spiral-wound cell 101 and the second current collector 108 serves as the current collector at the cathode of the spiral-wound cell 101.
In some embodiments, the battery cell further includes an insulating sleeve 109, the insulating sleeve 109 is cylindrically shaped, and the spiral-wound cell 101 is inserted in the insulating sleeve 109. The battery cell further includes an insulating ring 127 sleeved on one end of the insulating sleeve 109, and the insulating ring 127 is disposed at the opposite end of the spiral-wound cell 101. The insulating ring 127 is further configured to enable the second current collector 108 to be fixed on the insulating sleeve 109. The insulating ring 127 has a through-hole, a terminal post 111 of the battery cell is allowed to pass through the through-hole to be connected to the second current collector 108.
Referring to
It should be noted that, when the traditional cooling methods are used, the first bursting line(s) 104 and the second bursting lines 105 can be arranged on the outside to reduce a possibility of breakage in production and transportation equipment.
In one embodiment, the housing 110 is cylindrically shaped, and the insulating sleeve 109 is inserted in the housing 110. One end of the housing 110 is opened, and the other end of the housing 110 is provided with an end cap 114, the end cap 114 and the housing 110 are shaped as an integrated structure. The opposite end of the spiral-wound cell 101 and the other end of the housing 110 are arranged at the same side, and the terminal post 111 extends out of the end cap 114. The radial part 113 is formed during a riveting process, the riveting of the terminal post 111 enables the diameter of the radial part 113 to be greater than the diameter of the post part 112 to prevent gas ejection from occurring in case of the thermal runaway.
In some embodiments, the terminal post 111 further includes an exposed part 115, the exposed part 115 is circular in shape and the diameter of the exposed part 115 is greater than the diameter of the post part 112. The material of the first insulating member 122 is an insulating rubber. The first insulating member 122 includes an axial part 116 and a radially convex part 117. The radially convex part 117 is annular in shape. One end of the axial part 116 is connected to the radial convex part 117, and the end face of the opposite end of the axial part 116 abuts against one side of the exposed part 115. The first insulating member 122 is sleeved on the post part 112.
In some embodiments, a center part of the end cap 114 of the housing 110 has a first mounting hole 118, the first mounting hole 118 is a stepped through hole; a big aperture part of the first mounting hole 118 is away from the opposite end of the spiral-wound cell 101, and a small aperture part of the first mounting hole 118 is adjacent to the opposite end of the spiral-wound cell 101.
In some embodiments, the battery cell further includes an insulating sheet 119, the insulating sheet 119 has a second mounting hole 120, the second mounting hole 120 is a stepped through-hole; a big aperture part of the second mounting hole 120 is away from the opposite end of the spiral-wound cell 101, while a small aperture part of the second mounting hole 120 is adjacent to the opposite end of the spiral-wound cell 101.
The stepped first mounting hole 118 and the second mounting hole 120 enable the thickness of the exposed part 115 of the terminal post 111 to be increased without increasing the total exposed height of the terminal post 111, thereby supporting a welding of a connection piece having large overcurrent during a battery production process.
In some embodiments, an inner surface of the end cap 114 of the housing 110 is provided with a boss part 121, and the boss part 121 is accommodated in the big aperture part of the second mounting hole 120, so that the second mounting hole 120 of the insulating sheet 119 is coaxial with the first mounting hole 118 of the end cap 114, and the positioning of the insulating sheet 119 on the inner surface of the end cap 114 of the housing 110 in the radial direction is realized. The radially convex part 117 is located at the small aperture part of the second mounting hole 120. The axial part 116 of the first insulating member 122 is arranged to pass through the small aperture part of the first mounting hole 118. The first insulating member 122 realized insulated isolation between the post part 112 of the terminal post 111 and the end cap 114.
In one embodiment, the material of the insulating sheet 119 is Polyfluoroalkoxy (PFA).
In some embodiments, the battery cell further includes a second insulating member 123, the second insulating member 123 is snapped onto the terminal post 111. The second insulating member 123 is further snapped onto the axial part 116 of the first insulating member 122. The material of the second insulating member 123 is PFA.
In some embodiments, the second insulating member 123 includes an annular part 124 and an axially wrapped part 125, and the axially wrapped part 125 is connected to one side surface of the annular part 124. The axially wrapped part 125 is configured to wrap the circumference of the exposed part 115 of the terminal post 111, and the annular part 124 is located between the inner side of the exposed part 115 and the bottom of the aperture of the big aperture part of the first mounting hole 118, so that the insulated isolation between the exposed part 115 of the terminal post 111 and the outer surface of the end cap 114 of the housing 110 is realized through the second insulating member 123.
In some embodiments, the battery cell further includes a conductive sheet 126 which is sleeved on the columnar portion 112 of the terminal post 111, one side of the conductive sheet 126 abuts against the insulating sheet 119 and a radially convex part 117, respectively. Thus, the insulated isolation between the conductive sheet 126 and the end cap 114 of the housing 110 is realized through the insulating sheet 119 and the first insulating member 122. The conductive sheet 126 is disposed between the insulating sheet 119 and the radial part 113. The insulating sheet 119 is disposed between the conductive sheet 126 and the end cap 114.
In some embodiments, the first current collector 102 is further connected to the housing 110, the first current collector 102 is recessed in the housing 110. In one embodiment, a periphery of the first current collector 102 and the housing 110 are connected by welding.
In some embodiments, the first current collector 102 is made of aluminum material and the second current collector 108 is made of copper material. The terminal post 111 is made of copper. The conductive sheet 126 is made of copper material.
It should be noted that the material of the first current collector 102 is not merely limited to aluminum, the first current collector 102 can also be made using other materials, while the material of the second current collector 108, the material of the terminal post 111 and the material of the conductive sheet are not only limited to copper, other materials can also be used according to the actual situation. In the production process, two ends of the spiral-wound cell 101 are welded with the first current collector 102 and the second current collector 108, respectively. The spiral-wound cell 101 is sleeved on the insulating sleeve 109 and is inserted into the housing 110. A welding needle inserts into the fluid injection hole 103 of the first current collector and makes the second current collector to be welded with the rear of the terminal post 111 through a center shaft hole of the spiral-wound cell 101. Then, the first current collector 102 and an opening of the housing 110 are pressed together and are welded using a periphery welding sealing process, the foil material of the cathode is naturally compressed. A part of the vacant foil material of the anode can be pre-compressed after the first current collector 102 is welded, electrolyte is injected through the electrolyte injection hole 103 of the first current collector 102. Negative pressure is further pumped out from this hole through the negative pressure formation, so that produced gas is pumped out during battery cell formation. Then, after the cover plate 100 is placed in the accommodating cavity 106, an end surface welding is used to seal the gap between the cover plate 100 and the first current collector 102.
In some embodiments, the battery cell is a cylindrical battery cell. In one embodiment, the battery cell is a power battery cell.
In some embodiments, the battery cell has a diameter ranging from 21 mm to 60 mm, and has a height ranging from 500 mm to 1500 mm. In one or some embodiments, a battery is further provided, the battery includes the battery cell provided in the at least one embodiment.
The foregoing only describes some selectable embodiments of the present disclosure, and is not intended to limit the present disclosure. Any modification, equivalent replacement, improvement, and the like, which are made within the spirit and the principle of the present disclosure, should all be included in the protection scope of the claims of the present disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202221185440.5 | May 2022 | CN | national |