CN221102315U

CN221102315U - Battery module structure

Info

Publication number: CN221102315U
Application number: CN202220766360.2U
Authority: CN
Inventors: 朱建政; 付垚; 俞会根
Original assignee: Beijing WeLion New Energy Technology Co ltd
Current assignee: Beijing WeLion New Energy Technology Co ltd
Priority date: 2022-03-31
Filing date: 2022-03-31
Publication date: 2024-06-07
Anticipated expiration: 2032-03-31

Abstract

The embodiment of the utility model discloses a battery module structure, which comprises a battery cell stack, wherein the battery cell stack is formed by stacking a plurality of battery cells, an interlayer is arranged between the battery cells, end plates are symmetrically arranged at two ends of the battery cell stack, side plates are symmetrically arranged at two side edges of the battery cell stack, and a cover plate is arranged at the top of the battery cell stack; the two ends of the side plate are fixedly connected with the end plates, and a first bar-shaped support is arranged at the center of the side surface of the battery cell on the side plate; the cover plate is provided with a second bar-shaped support at the center of the battery cell, and two ends of the second bar-shaped support are respectively connected with end plates at two sides. According to the utility model, the supporting structures are respectively arranged on the side plates and the cover plate so as to improve the overall structural strength of the side plates and the cover plate, when the battery cells expand or move, the supporting structures can restrict the movement of the battery cells in the width direction, the height direction and the length direction, the side plates and the cover plate are ensured to bear larger stress and cannot crack, and the side plates and the cover plate are integrated, so that the number of parts is reduced, and the light weight effect is achieved.

Description

Battery module structure

Technical Field

The embodiment of the utility model relates to the technical field of battery modules, in particular to a battery module structure.

Background

In recent years, with the development of lithium battery technology, the energy density of a power battery system is also improved year by year; according to some mainstream designs at present, in order to further improve the energy density and space utilization rate of the battery system and reduce the cost of the power battery system, the module structure gradually increases to a large-module and high-integration design; according to statistics, the application of the large module product improves the utilization rate of a battery pack volume by 15% -20%, reduces the number of parts of the battery pack by 40%, improves the production efficiency by 50%, improves the energy density of the battery pack by 10% -15%, can reach more than 200Wh/kg, and greatly reduces the manufacturing cost of the power battery, but as the module is larger, the structural strength and the fixing mode of the module have larger hidden dangers.

At present, most square shell module schemes basically adopt electric core to stack up the back, form the electric core stack of certain size, and the both ends of electric core stack are equipped with the end plate for with electric core precompaction, the both sides limit of electric core stack is through structure gluing bonding curb plate, curb plate and end plate welded connection, busbar and collection pencil are placed at the top of electric core stack, then insulating apron protects electric core stack high pressure part, forms battery module. However, there are some problems with such a battery module:

1. the battery module is fixed with the battery box through the end plate, if a large module structure is adopted, the weight of the module is larger and larger along with the longer and longer length of the battery module, the fixing mode can lead to insufficient middle supporting strength of the battery module, and the battery core at the middle position of the module is easy to move, so that the module structure is invalid;

2. The traditional PTC (positive temperature coefficient) heating plate generally adopts a heating film, the heating film is arranged at the bottom of the module, and the heat of the heating film is transferred to the bottom of the battery cell through a heat conducting pad; the structure occupies the space in the height direction of the module, so that the utilization rate of the space in the height direction of the module is reduced; the heating film is easy to be pierced by foreign matters such as burrs of the module, and insulation problems occur; the PTC heating plate is pressed by the module by self gravity, so that the heating film is easy to collapse, and the heating film is in poor contact with the battery cell, so that the heating effect is poor;

3. The busbar, the acquisition wire harness and the plastic support piece are arranged at the top of the module, and are fragile, and if the size of the module is too large, the plastic support piece is easy to deform and damage; the battery cell is easy to move upwards in the vibration process, so that the module group is easy to loosen in the vibration process.

Therefore, it is necessary to provide a large module structure to solve the problems existing in the conventional module design.

Disclosure of utility model

Therefore, the embodiment of the utility model provides a battery module structure to solve the problem that the design of the traditional large module is unreasonable and the design requirement of the large module cannot be met.

In order to achieve the above object, the embodiment of the present utility model provides the following technical solutions:

The battery module structure comprises a battery cell stack, wherein the battery cell stack is formed by stacking a plurality of battery cells, an interlayer is arranged between the battery cells, end plates are symmetrically arranged at two ends of the battery cell stack, side plates are symmetrically arranged at two side edges of the battery cell stack, and a cover plate is arranged at the top of the battery cell stack; the two ends of the side plate are fixedly connected with end plates, and a first strip-shaped support is arranged at the center of the side surface of the battery cell on the side plate; the cover plate is provided with a second bar-shaped support at the center of the battery cell, and two ends of the second bar-shaped support are respectively connected with end plates at two sides.

Further, the interlayer comprises a fireproof plate and PU foam, and the fireproof plate and the PU foam are mutually adhered.

Further, the first strip-shaped support is of a tubular cavity structure.

Further, a heating plate is arranged in the first strip-shaped support and is connected with a heating controller.

Further, the end plate is of a double-layer hollow structure, and the heating controller is buried in the end plate.

Further, the outer layer structure of the end plate is an arc-shaped plate.

Further, a transverse connecting plate is arranged at the top of the end plate, and the transverse connecting plate is detachably connected with the second strip-shaped support.

Further, a support column is arranged between the end plate and the cover plate, and the end plate and the cover plate are respectively detachably connected with the support column.

Further, the second bar-shaped support is of a cavity structure with at least one end open, the second bar-shaped support is provided with a pressure relief hole corresponding to the battery cell, and a pressure relief channel is formed in the second bar-shaped support.

Further, the cover plate comprises a second bar-shaped support and a PCB (printed circuit board), wherein both sides of the second bar-shaped support are fixedly connected with the PCB, and a busbar is arranged on the PCB.

The embodiment of the utility model has the following advantages:

1. the battery module structure is characterized in that the battery cells are provided with the interlayer, so that the battery module structure has the functions of buffering, insulating heat and controlling thermal runaway, is simple and feasible, has low cost, effectively blocks contact heat conduction between the battery cells, and blocks the battery cells into independent spaces.

2. According to the battery module structure, the supporting structures are respectively arranged at the stress centers of the side plates and the cover plate, so that the overall structural strength of the side plates and the cover plate is improved, the stability of the side plates and the cover plate is improved, when the battery cells expand or play, the supporting structures can restrict the expansion of the battery cells in the width direction, limit the play of the battery cells in the height direction and the length direction, ensure that the side plates and the cover plate bear larger stress and cannot crack, the cover plate and the side plates adopt an integrated design, the number of parts is reduced, the weight of the parts is reduced, and therefore the effect of light weight is achieved.

3. According to the battery module structure, the heating device is arranged on the side plate, the heating plate generates heat and transmits the heat to the inside of the battery core through the excellent heat conduction performance of the side plate, and the side plate serves as a structural member to limit the battery core, so that the module structure is compact, and the overall strength and rigidity are good.

4. According to the battery module structure, the module cover plate is designed into the integrated cover plate integrating the pressing plate, the PCB, the bus bar and the pressure release channel, so that the number of parts is reduced, the space utilization rate of the module in the height direction is improved, the design of the high-integration cover plate is realized, the weight of the module is reduced, and the structural strength of the cover plate is greatly improved.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It will be apparent to those of ordinary skill in the art that the drawings in the following description are exemplary only and that other implementations can be obtained from the extensions of the drawings provided without inventive effort.

The structures, proportions, sizes, etc. shown in the present specification are shown only for the purposes of illustration and description, and are not intended to limit the scope of the utility model, which is defined by the claims, so that any structural modifications, changes in proportions, or adjustments of sizes, which do not affect the efficacy or the achievement of the present utility model, should fall within the ambit of the technical disclosure.

Fig. 1 is a product structural view of a battery module structure according to an embodiment of the present utility model;

FIG. 2 is an exploded view of FIG. 1;

FIG. 3 is a block diagram of the side panel of FIG. 1;

FIG. 4 is a bottom view of the cover plate of FIG. 1;

Fig. 5 is a high voltage protective cover mounting diagram of a battery module structure according to an embodiment of the present utility model.

In the figure:

1. A battery cell; 2. an interlayer; 3. a side plate; 4. a first bar support; 5. a heating sheet; 6. a pressure relief hole; 7. folding edges; 8. an end plate; 9. a hoisting hole; 10. a transverse connection plate; 11. a support column; 12. a cover plate; 13. a second bar support; 14. a PCB board; 15. a busbar; 16. high pressure protective cover.

Detailed Description

Other advantages and advantages of the present utility model will become apparent to those skilled in the art from the following detailed description, which, by way of illustration, is to be read in connection with certain specific embodiments, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

As shown in fig. 1-2, a battery module structure comprises a battery cell stack, wherein the battery cell stack is formed by stacking a plurality of battery cells, and an interlayer 2 is arranged between the battery cells 1 and used for dividing adjacent battery cells 1 into independent units, so that the battery cell stack has the functions of buffering, heat insulation and controlling thermal runaway. Specifically, the interlayer 2 comprises a fireproof plate and PU foam, and the fireproof plate and the PU foam are adhered by double-sided adhesive tapes, wherein the fireproof plate is used for preventing heat of the battery cells 1 which are out of control from diffusing to the peripheral battery cells 1, so that the heat generated by each battery cell 1 is ensured not to be transferred to the adjacent battery cells 1, and the effect of thermal insulation is achieved. The PU foam has a lower heat conductivity coefficient, generally 0.2-0.3W/(m.K), and also has the properties of low hardness and high resilience, and is used for absorbing the expansion amount of the battery cell 1 in the charge and discharge processes, playing a role in buffering, ensuring the battery cell 1 to work in an optimal pretightening force interval, and prolonging the service life of the module. When the electric core 1 is out of control, the interlayer 2 can inhibit heat diffusion caused by contact between the electric cores 1, and prevent heat from diffusing to other electric cores 1, and the fireproof plate in the interlayer 2 has a flame retardant effect, so that fire spreading can be delayed.

As shown in fig. 3, side plates 3 are respectively arranged at two side edges of the cell stack, the inner side surfaces of the side plates 3 are bonded with the cell stack through heat-conducting glue, and the side plates 3 are made of metal materials, such as stainless steel, aluminum alloy and the like. The center department that lies in electric core 1 side on the curb plate 3 is equipped with first bar support 4, first bar support 4 is metal material, like stainless steel, aluminum alloy etc. for increase the rigidity of curb plate 3, in order to improve the bulk strength of curb plate 3. In this embodiment, the first bar-shaped support 4 is arranged at the center of the side plate 3, for the traditional double-layer side plate or thickened side plate, the first bar-shaped support 4 is arranged at the stressed core of the side plate 3, the structural strength and rigidity of the side plate 3 are greatly increased, the side plate 3 can provide larger pressing force to press the battery cell 1, the module structure is compact, the strength is improved, and the weight of the side plate 3 is not excessively increased under the condition of improving the strength of the side plate 3.

The first strip-shaped support 4 is of a tubular cavity structure, so that the first strip-shaped support 4 is changed into a cavity structure, the cavity structure can provide larger rigidity, the deformation size is small when bearing larger force, the stability is good, and excessive weight is not increased relative to the plate-shaped structure. The first bar-shaped support 4 can be internally provided with a temperature adjusting device so as to realize the function of adjusting the temperature of the electric core 1 through heat conduction of the side plate 3. In this embodiment, a heating plate 5 is disposed in the first bar-shaped support 4, and the heating plate 5 is connected to a heating controller. The PCB board 14 has a temperature collection function, collects the temperature of the positive and negative electrode posts of the electric core 1, and outputs the temperature to a Battery Management System (BMS), the battery management system sends an opening instruction or a disconnection instruction to a controller through a certain control strategy (for example, the electric core 1 collects the temperature lower than 10 ℃ and is heated higher than 15 ℃ and is heated in a closing mode), the controller controls the heating state of the heating sheet 5 according to the control instruction, the heating sheet 5 conducts heat through the side plate 2 when heating the side plate 3, and the side plate 3 contacts with the side wall of all the electric cores 1, so that the local heating of the heating sheet 5 is diffused through the side plate 3, uniform heating of the electric core 1 can be realized, the problem of local thermal runaway caused by local overheating of the electric core 1 can not occur, and the consistency of the temperature of the electric core 1 is ensured.

The hem 7 of taking the mounting hole is equipped with at curb plate 3 top for with curb plate 3 and battery box fixed connection, increase the steadiness between battery module structure and the battery box, the support atress of dispersion end plate 8 has improved end plate 8's life, can not take place fixing bolt and become flexible or cracked situation. The top of the side plate 3 is not limited to the structure of the folded edge 7, and the structure for connecting with external equipment falls into the protection scope of the patent as long as the structure is a transverse plate body fixed at the top of the side plate 3 and provided with a mounting hole.

The two ends of the side plate 3 are fixedly connected with the end plate 8, in this embodiment, the two ends of the side plate 3 are connected with the end plate 8 through laser welding to form a frame structure, so that the side plate 3 can bear the expansion force of the cell stack without deformation or fracture failure. The end plates 8 are arranged at two ends of the cell stack, the end plates 8 are made of metal materials, such as stainless steel, aluminum alloy and the like, and the end plates 8 are respectively connected with the second bar-shaped support 13, the side plates 3, the cell box mounting beams and other external equipment, so that the end plates 8 are required to have enough strength and rigidity, in the embodiment, the end plates 8 are of double-layer hollow structures, the end plates 8 are extrusion profile plates with hollow structures, the parts of the hollow structures can provide larger rigidity, the deformation size is small when bearing larger force, the stability is good, a certain pretightening force can be applied to the cell stack, the module structure is more compact, the expansion of the cell 1 is limited by providing enough restraining force, and the hollow structures can reduce the weight to the greatest extent, so that the cell module structure tends to be light. The controller is arranged in the end plate 8, a channel (not shown in the figure) for the heating plate 5 to enter the end plate 8 is arranged at the joint of the side plate 3 and the end plate 8, and through holes are formed at the joint of the side plate 3 and the end plate 8, so that the heating plate 5 is prevented from being exposed outside, and the function of protecting equipment is achieved.

The end plate 8 is provided with a lifting hole 9 connected with external equipment, the lifting hole 9 supports the stress of the whole battery module structure in the lifting process, in order to increase the stability of the end plate 8, the outer side of the end plate 8 is an arc plate, the arc plate structure has larger rigidity relative to the flat plate, and the deformation is smaller under the condition of bearing the same force.

The top of end plate 8 is equipped with transverse connection board 10, be equipped with the connecting hole of being connected with apron 12 or external equipment on the transverse connection board 10, all can dismantle through the bolt between transverse connection board 10 and apron 12 or the external equipment and be connected, end plate 8 mounting hole is designed to be sunken to end plate 8 inside, and is fixed with external equipment through the short bolt. In the embodiment, the bolt is preferably a short bolt, the short bolt is light in weight, and the light weight effect is better; the short bolts have better connection rigidity and stability, and the short bolts are not easy to break in the vibration process.

The support column 11 is arranged between the end plate 8 and the cover plate 12 and is used for supporting the end plate 8 and the cover plate 12 so as to make up the distance between the end plate 8 and the cover plate 12, compared with the technical scheme that the support column 11 and the end plate 8 are of an integrated structure, the processing cost of the technical scheme that the support column 11 and the end plate 8 are separated is lower, and the effects of the two schemes are the same.

As shown in fig. 4, the cover 12 is an integrated design integrating the second bar-shaped support 13, the PCB board 14 and the bus bar 15. The cover plate 12 is provided with a second bar-shaped support 13 at the center of the top surface of the battery cell 1, the second bar-shaped support 13 is made of metal materials, such as stainless steel, aluminum alloy, and the like, and if the battery cell stack is a double-row battery cell 1, the cover plate 12 is provided with two second bar-shaped supports 13. When the battery cell 1 moves, the second bar-shaped support 13 can restrict the battery cell 1 to prevent the battery cell from moving in the length and height directions, so that the stress on two sides of the cover plate 12 is reduced, and compared with the traditional module cover plate 12, the cover plate 12 has high integration, reduces the number of parts, reduces the cost and has obvious weight reduction effect, thereby reducing the weight of the battery module structure. The second bar-shaped support 13 is fixedly connected with the end plate 8 through bolts, so that the connection stability between the end plate 8 and the cover plate 12 can be improved.

The second bar-shaped support 13 is of a cavity structure with at least one end open, the second bar-shaped support 13 is provided with a pressure relief hole 6 corresponding to the battery cell 1, a pressure relief channel is formed in the second bar-shaped support 13, the pressure relief hole 6 is opposite to an explosion-proof valve of the battery cell 1, directional pressure relief is realized when the battery cell 1 is in thermal runaway, the battery cell 1 is isolated into an independent space by combining the interlayer 2, heat sprayed by the battery cell 1 is discharged out of the module structure along the pressure relief channel in a directional manner, the mutual heat conduction influence between the battery cells 1 is effectively isolated, so that the diffusion of thermal runaway is avoided, and the safety of other battery cells 1 is ensured.

As shown in fig. 5, two sides of the second bar-shaped support 13 are fixedly connected with a horizontally arranged PCB board 14, a busbar 15 is arranged on the PCB board 14, a high-voltage protection cover 16 covering the busbar 15 is arranged on the cover plate 12, and the high-voltage protection cover 16 is reversely buckled on the outer side of the busbar 15 to prevent foreign matters from falling into or mistakenly touching a high-voltage part of the module.

While the utility model has been described in detail in the foregoing general description and specific examples, it will be apparent to those skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the utility model and are intended to be within the scope of the utility model as claimed.

Claims

1. A battery module structure, characterized in that: the battery cell module comprises a battery cell stack, wherein the battery cell stack is formed by stacking a plurality of battery cells, an interlayer is arranged between the battery cells, end plates are symmetrically arranged at two ends of the battery cell stack, side plates are symmetrically arranged at two side edges of the battery cell stack, and a cover plate is arranged at the top of the battery cell stack;

The two ends of the side plate are fixedly connected with end plates, and a first strip-shaped support is arranged at the center of the side surface of the battery cell on the side plate;

the cover plate is provided with a second bar-shaped support at the center of the top surface of the battery cell, and two ends of the second bar-shaped support are respectively connected with end plates at two sides.

2. The battery module structure according to claim 1, wherein: the interlayer comprises a fireproof plate and PU foam, and the fireproof plate and the PU foam are mutually adhered.

3. The battery module structure according to claim 1, wherein: the first bar-shaped support is of a tubular cavity structure.

4. The battery module structure according to claim 1, wherein: and a heating plate is arranged in the first strip-shaped support and is connected with a heating controller.

5. The battery module structure according to claim 4, wherein: the end plate is of a double-layer hollow structure, and the heating controller is buried in the end plate.

6. The battery module structure according to claim 5, wherein: the outer layer structure of the end plate is an arc-shaped plate.

7. The battery module structure according to claim 1, wherein: the top of end plate is equipped with the transverse connection board, can dismantle between transverse connection board and the second bar support and be connected.

8. The battery module structure according to claim 1, wherein: support columns are arranged between the end plate and the second bar-shaped support, and the end plate and the second bar-shaped support are respectively detachably connected with the support columns.

9. The battery module structure according to claim 1, wherein: the second bar-shaped support is of a cavity structure with at least one end open, and the second bar-shaped support is provided with a pressure relief hole corresponding to the battery cell.

10. The battery module structure according to claim 1, wherein: the cover plate comprises a second bar-shaped support and a PCB, wherein two sides of the second bar-shaped support are fixedly connected with the PCB, and a busbar is arranged on the PCB.