CN219419348U - Battery pack - Google Patents

Abstract

The utility model relates to the technical field of batteries, in particular to a battery pack. The battery pack includes: the battery cell module comprises a box body and a battery cell module, wherein the box body comprises a bottom plate, a cover plate and a frame connected between the bottom plate and the cover plate, the bottom plate comprises an upper layer plate and a lower layer plate which are arranged at intervals in parallel, reinforcing ribs are arranged between the upper layer plate and the lower layer plate, and the reinforcing ribs are obliquely arranged between the upper layer plate and the lower layer plate; the cell module is mounted in the housing. Through setting up the bottom plate for including interval and parallel arrangement's top plate and the bilayer plate structure of lower plywood to connect through the strengthening rib between the two-layer board, strengthened the intensity of bottom plate, the bottom plate supports the cell module, and the bottom plate of bilayer plate structure has functions such as energy-absorbing, buffering in the transmission of power to, adopt the inclined rib to connect between top plate and the lower plywood, further strengthened the stability of structure, the bottom plate can provide the deformation of high strength and the amortization of power when receiving external impact, and then carries out comprehensive protection to the cell module.

Description

Battery pack

Technical Field

The utility model relates to the technical field of batteries, in particular to a battery pack.

Background

With the great development of new energy automobiles, the safety of electric automobiles is getting more and more attention. In the running process of the electric automobile, various complex working conditions can be met, the battery pack is used as a power source of the electric automobile, and the safety of the battery pack has a great influence on the safety of the whole automobile. Therefore, in order to improve the capability of the electric vehicle to cope with various working conditions, the safety performance of the battery pack needs to be improved.

Currently, the self-ignition of the battery pack caused by impact, particularly bottom impact, occupies a certain proportion of the safety accidents of the electric vehicle. The bottom surface of the battery pack is required to bear the gravity action of the battery core module and directly bear the external impact, so that the bottom surface of the battery pack in the prior art is usually easy to be impacted and damaged, and the bottom impact resistance is weaker, so that the safety of the battery pack is not facilitated.

Disclosure of Invention

Therefore, the utility model aims to overcome the defect of weak impact resistance of the bottom surface of the battery pack in the prior art, thereby providing the battery pack capable of improving the impact resistance of the bottom.

In order to solve the above problems, the present utility model provides a battery pack including: the box body comprises a bottom plate, a cover plate and a frame connected between the bottom plate and the cover plate, wherein the bottom plate comprises an upper layer plate and a lower layer plate which are arranged at intervals in parallel, reinforcing ribs are arranged between the upper layer plate and the lower layer plate, and the reinforcing ribs are obliquely arranged between the upper layer plate and the lower layer plate; and the battery cell module is arranged in the box body.

Optionally, the included angle a between the reinforcing rib and the lower layer plate is 25-65 degrees.

Optionally, the thickness b of the bottom plate is 1/10-1/4 of the height of the box body.

Optionally, the value range of the thickness c of the reinforcing rib is 1/5-1/2 of the thickness b of the bottom plate; and/or the distance d between two adjacent reinforcing ribs is 6-9 times of the thickness b of the bottom plate.

Optionally, a cooling structure is arranged between the upper layer plate and the lower layer plate to reduce the temperature of the battery cell module; and/or elastic materials are filled between the upper layer plate and the lower layer plate so as to buffer the bottom plate.

Optionally, the bottom plate is one or a combination of more of an aluminum plate, a steel plate and a plastic plate.

Optionally, an exhaust channel is arranged on the bottom plate, and the exhaust channel penetrates through the upper layer plate and the lower layer plate to exhaust high-temperature flue gas in the box body when the battery cell module is out of control thermally.

Optionally, the width e of the exhaust channel is 1.2-1.5 times of the size of the explosion-proof valve on the battery cell module; and/or the length f of the exhaust channel is 1.1-1.3 times of the length of the battery cell module.

Optionally, the battery pack further includes: a first adhesive disposed between the base plate and the cell module to adhere the base plate and the cell module; and the second adhesive is arranged between the cover plate and the cell module so as to bond the cover plate and the cell module.

Optionally, the cover plate is a liquid cooling plate to cool the cell module.

The utility model has the following advantages:

1. through setting up the bottom plate for including interval and parallel arrangement's top plate and the bilayer plate structure of lower plywood to connect through the strengthening rib between the two-layer board, strengthened the intensity of bottom plate, the bottom plate supports the cell module, and the bottom plate of bilayer plate structure has functions such as energy-absorbing, buffering in the transmission of power to, adopt the inclined rib to connect between top plate and the lower plywood, further strengthened the stability of structure, the bottom plate can provide the deformation of high strength and the amortization of power when receiving external impact, and then carries out comprehensive protection to the cell module.

2. Through set up cooling structure in the space between upper plate and lower plate, can realize that the bottom plate cools down the cooling to electric core module, prevent that electric core temperature from being too high and causing the damage, guarantee electric core module's security to space between upper plate and the lower plate can rational utilization, the bottom plate has cooling and support function concurrently simultaneously, reduces the height of whole device, thereby reduces the volume of battery package, practices thrift installation space.

3. Elastic materials are filled between the upper layer plate and the lower layer plate, and can absorb external acting force when the bottom plate is impacted by the outside, so that the effects of shock absorption and buffering are achieved, the rigid damage of the bottom plate is reduced, and the protection effect on the cell module is achieved.

4. Through set up exhaust passage on the bottom plate, be particularly useful for the explosion-proof valve of electric core module down the condition, preferably, exhaust passage corresponds the setting with the explosion-proof valve, the position department design that corresponds with the explosion-venting valve on the bottom plate promptly becomes hollow out construction, form the pressure release passageway, then when electric core module takes place thermal runaway, from the high temperature flue gas of explosion-proof valve department can directly follow exhaust passage discharge battery package, reduce the stay and the conveying of high temperature flue gas in the battery package, improve and promote thermal runaway exhaust performance, thereby reduce the further damage to electric core module.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present utility model, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.

Fig. 1 shows an exploded view of a battery pack according to an embodiment of the present utility model;

FIG. 2 shows a schematic structural view of a base plate according to an embodiment of the present utility model;

FIG. 3 shows an enlarged partial schematic view of section A-A of FIG. 2;

FIG. 4 shows a partial schematic view of a top view of the base plate of FIG. 2;

FIG. 5 shows a partial schematic view of a battery pack model;

FIG. 6 is a graph showing simulation results of deformation of a battery pack model after bottom ball striking using a bottom plate before modification;

FIG. 7 is a graph showing the results of simulation of the deformation of a battery pack model using a base plate of an embodiment of the present utility model after a bottom ball impact;

FIG. 8 shows a box strain results schematic of a battery pack prior to modification;

fig. 9 is a diagram showing a case strain result of a battery pack according to an embodiment of the present utility model;

FIG. 10 shows a force diagram of a case of a battery pack prior to modification;

fig. 11 shows a force diagram of a case of a battery pack according to an embodiment of the present utility model.

Reference numerals illustrate:

10. a case; 11. a bottom plate; 111. an upper plate; 112. a lower plate; 113. reinforcing ribs; 114. an exhaust passage; 12. a cover plate; 13. a frame; 20. a cell module; 31. a first binder; 32. and a second binder.

Detailed Description

The following description of the embodiments of the present utility model will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the utility model are shown. 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.

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In addition, the technical features of the different embodiments of the present utility model described below may be combined with each other as long as they do not collide with each other.

As shown in fig. 1 to 4, the battery pack of the present embodiment includes: the cell module 20 comprises a box body 10 and a cell module 20, wherein the box body 10 comprises a bottom plate 11, a cover plate 12 and a frame 13 connected between the bottom plate 11 and the cover plate 12, the bottom plate 11 comprises an upper layer plate 111 and a lower layer plate 112 which are arranged at intervals in parallel, reinforcing ribs 113 are arranged between the upper layer plate 111 and the lower layer plate 112, and the reinforcing ribs 113 are obliquely arranged between the upper layer plate 111 and the lower layer plate 112; the cell module 20 is mounted within the housing 10.

The battery pack of this embodiment is applied, through setting up bottom plate 11 for including interval and parallel arrangement's upper plate 111 and the double-deck board structure of lower plate 112, and connect through strengthening rib 113 between the two-deck board, strengthened the intensity of bottom plate 11, bottom plate 11 supports electric core module 20, the bottom plate 11 of double-deck plate structure has functions such as energy-absorbing, buffering in the transmission process of power, and adopt the inclined rib to connect between upper plate 111 and the lower plate 112, further strengthened the stability of structure, bottom plate 11 can provide the deformation of high strength and the amortization of power when receiving external impact, and then carry out comprehensive protection to electric core module 20.

The upper plate 111 of the bottom plate 11 is a plate facing the inside of the case 10, and the lower plate 112 is a plate facing the outside of the case 10; the cell module 20 includes a plurality of electric core that arrange in proper order, and the cell module 20 is installed in the box 10, and bottom plate 11 plays the supporting role to cell module 20, and to the electric core that the utmost point post is down, bilayer structure's of this embodiment bottom plate 11 can provide the buffering protection better, reduces the damage of utmost point post, of course, to the electric core that the utmost point post is towards both sides, the bottom plate 11 of this embodiment also has the guard action to the electric core bottom, wherein, refer to "down" that the arrow point in fig. 1 down.

In this embodiment, the included angle a between the reinforcing rib 113 and the lower plate 112 is in the range of 25 ° to 65 °. The included angle a is an acute angle formed between the reinforcing rib 113 and the lower plate 112, and the size of the included angle a is also equal to an acute angle formed between the reinforcing rib 113 and the upper plate 111, and when the included angle a is between 25 ° and 65 °, the bottom plate 11 formed by the upper plate 111, the lower plate 112 and the reinforcing rib 113 has higher strength and buffering performance.

In the present embodiment, the thickness b of the bottom plate 11 is 1/10 to 1/4 of the height of the case 10. Wherein, the height of the case 10 refers to the dimension along the "height direction" indicated by the arrow in fig. 1 when the case 10 is assembled; the thickness b of the bottom plate 11 refers to the dimension of the bottom plate 11 along the height direction shown in fig. 1, and the thickness b of the bottom plate 11 is specifically determined according to the stress of the cell module 20 and the overall package height dimension, and is generally 1/10-1/4 of the height of the box 10, so that the bottom plate 11 can be ensured to have stronger strength, and the arrangement of the components such as the cell module 20 in the box can not be influenced by excessive thickness.

In this embodiment, the value of the thickness c of the reinforcing rib 113 is 1/5-1/2 of the thickness b of the bottom plate 11, the reinforcing rib 113 has a certain thickness, which can better play a role in connection and support, and the thickness of the reinforcing rib 113 in this range can not only meet the strength required by support, but also avoid the overlarge mass of the bottom plate 11 caused by overlarge thickness, thereby relatively reducing the mass of the bottom plate 11, i.e. the mass of the whole battery pack, and being beneficial to improving the energy density of the battery pack.

In this embodiment, the distance d between two adjacent reinforcing ribs 113 is 6-9 times the thickness b of the bottom plate 11, so that the distribution density of the reinforcing ribs 113 formed can not only meet the supporting effect of the reinforcing ribs 113, but also relatively reduce the mass of the bottom plate 11, thereby realizing the weight reduction of the battery pack.

In this embodiment, a cooling structure is disposed between the upper plate 111 and the lower plate 112 to reduce the temperature of the cell module 20. Through set up the cooling structure in the space between top plate 111 and bottom plate 112, can realize bottom plate 11 to the cooling of electricity core module 20, prevent that electricity core temperature from being too high and causing the damage, guarantee the security of electricity core module 20 to can rationally utilize the space between top plate 111 and the bottom plate 112, bottom plate 11 has cooling and support function concurrently, reduces the height of whole device, thereby reduces the volume of battery package, practices thrift installation space. Specifically, the cooling structure may be a pipeline through which liquid is led, and heat of the battery cell module 20 is carried away through heat exchange; the cooling structure may also be a filler material having heat absorbing properties that fills between the upper plate 111 and the lower plate 112 to achieve cooling by absorbing heat from the cell core module 20.

In the present embodiment, an elastic material is filled between the upper plate 111 and the lower plate 112 to buffer the bottom plate 11. The elastic material can absorb external acting force when the bottom plate 11 is impacted by the outside, plays roles of shock absorption and buffering, reduces rigidity damage of the bottom plate 11, and plays a role of protecting the cell module 20.

Wherein, only one of the cooling structure and the elastic material can be arranged between the upper layer plate 111 and the lower layer plate 112, and the cooling structure and the elastic material can be simultaneously arranged, and the cooling structure and the elastic material can be specifically selected according to actual needs. Of course, a multiphase medium or a solid-liquid medium having both heat absorbing function and elastic property may be filled between the upper plate 111 and the lower plate 112, and cooling of the cell module 20 and buffering of external impact force may be achieved. It should be noted that, when the cooling combination and/or the elastic material is provided, the exhaust channel 114 needs to be avoided, so as to ensure the smoothness of the exhaust channel 114.

In the present embodiment, the bottom plate 11 is one of an aluminum plate, a steel plate, and a plastic plate, and may be a combination of a plurality of the above plates. Aluminum and steel have high strength, and plastic has light weight, corrosion resistance and the like, and can be specifically selected according to actual environment and needs.

In the present embodiment, the bottom plate 11 is provided with an exhaust passage 114, and the exhaust passage 114 penetrates the upper plate 111 and the lower plate 112 of the bottom plate 11 to exhaust high-temperature fumes inside the case 10 when thermal runaway of the cell module 20 occurs. Through setting up exhaust passage 114 on bottom plate 11, be particularly useful for the explosion-proof valve of electricity core module 20 condition down, preferably, exhaust passage 114 sets up with the explosion-proof valve corresponds, namely the position department design that corresponds with letting out the explosion-proof valve on the bottom plate 11 becomes hollow out construction, form the pressure release passageway, then when electricity core module 20 takes place thermal runaway, the battery package can be directly discharged from exhaust passage 114 to the high temperature flue gas of follow explosion-proof valve department, reduce the stay and the conveying of high temperature flue gas in the battery package, improve and promote thermal runaway exhaust performance, thereby reduce the further damage to electricity core module 20. Further, the number of the exhaust channels can be set according to the arrangement of the single cells of the cell module 20, preferably, the cell module 20 includes two rows of cells, the number of the exhaust channels 114 is two, the two exhaust channels 114 are arranged at intervals along the width direction of the bottom plate 11, and each exhaust channel 114 corresponds to an explosion-proof valve on one row of cells, so that the exhaust area is increased, and the exhaust effect is improved.

In this embodiment, the width e of the vent channel 114 is 1.2-1.5 times the size of the explosion-proof valve on the cell module 20, ensuring that the gas ejected from the explosion-proof valve can be smoothly vented through the vent channel 114. Wherein width refers to the dimension along the "width direction" indicated by the arrow in fig. 4; the explosion-proof valve refers to an explosion-proof valve on a battery cell monomer in the battery cell module 20, the battery cell module 20 comprises a plurality of battery cell monomers, each battery cell monomer is provided with an explosion-proof valve, and the explosion-proof valve is opened when the battery cell monomer is out of control to discharge high-temperature smoke in the battery cell monomer.

In this embodiment, the length f of the exhaust channel 114 is 1.1-1.3 times the length of the cell module 20. The length refers to the dimension along the "length direction" indicated by the arrow in fig. 1 and 4, and by setting the length of the exhaust channel 114 to be greater than the length of the cell module 20, it can be ensured that the gas ejected from the cell unit at any position on the cell module 20 can be smoothly exhausted through the exhaust channel 114, so as to further improve the safety of the battery pack.

In this embodiment, the battery pack further includes: a first adhesive 31 and a second adhesive 32, the first adhesive 31 being disposed between the base plate 11 and the cell module 20 to bond the base plate 11 and the cell module 20; a second adhesive 32 is disposed between the cover plate 12 and the cell module 20 to bond the cover plate 12 to the cell module 20. By arranging the first adhesive 31 between the bottom plate 11 and the cell module 20 and the second adhesive 32 between the cover plate 12 and the cell module 20, the adhesive force between the bottom plate 11 and the cell module 20 and between the cover plate 12 and the cell module 20 is improved, the cell module 20 is prevented from shaking, and the stability of the structure is improved.

In this embodiment, the cover plate 12 is a liquid cooling plate to cool the battery cell module 20, and the cover plate 12 and the bottom plate 11 can cool the battery cell module 20 at the same time, so as to increase the cooling effect and protect the battery cell under the high-power fast-charging working condition.

The performance of the battery pack of this embodiment is described in comparison with the performance of the battery pack before improvement as follows:

as shown in fig. 5, the battery pack is modeled by using structural simulation software, the original height of the battery pack is 130.020mm, and the condition that the battery pack is impacted by the outside is simulated by applying a ball impact on the bottom of the battery pack, specifically, external forces with the same magnitude are applied to the battery pack before improvement and the battery pack of the embodiment in the form of ball impact, after the bottom plate is impacted by the ball impact, the stress is gradually increased, and the battery pack is correspondingly deformed, as shown in fig. 6 to 11, simulation results of the battery pack using the bottom plate before improvement and the battery pack using the bottom plate 11 of the embodiment are compared, and the specific analysis is as follows:

fig. 6 and fig. 7 show that when the stress on the bottom plate reaches 25KN, the deformation amounts of the battery pack before improvement and the battery pack of the embodiment are compared, and as can be seen, the height of the battery pack before improvement is 126.914mm, the height of the battery pack of the embodiment is 129.040mm, and compared with the deformation amount of the battery pack before improvement, the deformation amount of the battery pack of the embodiment is reduced to 0.98mm and less than 2.0mm of the reference requirement, and the simulation result shows that the shell of the battery cell unit, namely the explosion-proof valve, is not broken, so that the battery pack of the embodiment meets the safety performance requirement and the deformation amount after external impact force is greatly reduced, and the battery pack performance is improved;

fig. 8 and 9 show that when the stress on the bottom plate reaches 25KN, the maximum strain on the battery pack before improvement is 3.077mm, the maximum strain on the battery pack of the embodiment is 1.019mm, the strain of the embodiment is greatly reduced, and the case of the battery pack of the embodiment is less prone to damage and the battery pack performance is better as can be seen by comparing the strain on the case 10 of the battery pack of the embodiment with the strain of the battery pack of the prior embodiment;

fig. 10 and 11 show graphs of the force variation on the bottom plate of the battery pack after the ball impact is performed on the bottom plate of the battery pack, and it can be seen that the slope of the force curve on the bottom plate of the battery pack before the improvement is basically gradually increased, while the slope of the force curve on the bottom plate of the battery pack of the embodiment is kept unchanged, which indicates that the force on the bottom plate of the battery pack of the embodiment is increased at a uniform speed, the force is more uniform, the damage to the bottom plate is smaller, and the performance of the battery pack is better.

In summary, compared with the battery pack before improvement, when the bottom plate is impacted by the same external force, the battery pack of the embodiment has smaller deformation, smaller strain on the box body and more uniform bottom plate stress, so the battery pack of the embodiment has better impact resistance and better safety performance.

From the above description, it can be seen that the above-described embodiments of the present utility model achieve the following technical effects:

1. the bottom plate 11 adopts a double-layer plate structure, and diagonal ribs are connected between the upper layer plate 111 and the lower layer plate 112, so that the whole structure is compact, the rigidity is high, and the weight is relatively light.

2. Through set up exhaust passage 114 on bottom plate 11, realize the bottom protection of bottom plate 11 and the multi-functional guard plate that exhaust function combined together, can also realize the cooling and/or the cushioning effect of bottom plate 11 through setting up cooling structure and/or elastic material at the intermediate space layer of bottom plate 11 simultaneously, structural design is ingenious, matches material and structure and synthetic design, and the bottom structure has multiple functions such as pressure release, cooling, protection to realize the requirement to the protection of electric core bottom and to the safety protection of electric core body.

It is apparent that the above examples are given by way of illustration only and are not limiting of the embodiments. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. While still being apparent from variations or modifications that may be made by those skilled in the art are within the scope of the utility model.

Claims (10)

1. A battery pack, comprising:

the box body comprises a bottom plate, a cover plate and a frame connected between the bottom plate and the cover plate, wherein the bottom plate comprises an upper layer plate and a lower layer plate which are arranged at intervals in parallel, reinforcing ribs are arranged between the upper layer plate and the lower layer plate, and the reinforcing ribs are obliquely arranged between the upper layer plate and the lower layer plate;

and the battery cell module is arranged in the box body.

2. The battery pack according to claim 1, wherein the included angle a between the reinforcing rib and the lower plate is in the range of 25 ° to 65 °.

3. The battery pack according to claim 1, wherein the thickness b of the bottom plate has a value ranging from 1/10 to 1/4 of the height of the case.

4. The battery pack according to claim 3, wherein the thickness c of the reinforcing rib has a value ranging from 1/5 to 1/2 of the thickness b of the bottom plate;

and/or the distance d between two adjacent reinforcing ribs is 6-9 times of the thickness b of the bottom plate.

5. The battery pack of claim 1, wherein a cooling structure is provided between the upper plate and the lower plate to reduce the temperature of the cell module;

and/or elastic materials are filled between the upper layer plate and the lower layer plate so as to buffer the bottom plate.

6. The battery pack of claim 1, wherein the bottom plate is a combination of one or more of an aluminum plate, a steel plate, and a plastic plate.

7. The battery pack according to claim 1, wherein the bottom plate is provided with a vent passage penetrating the upper plate and the lower plate to vent high-temperature smoke in the case when thermal runaway of the battery cell module occurs.

8. The battery pack of claim 7, wherein the width e of the vent channel is 1.2-1.5 times the size of the explosion-proof valve on the cell module;

and/or the length f of the exhaust channel is 1.1-1.3 times of the length of the battery cell module.

9. The battery pack according to any one of claims 1 to 8, further comprising:

a first adhesive disposed between the base plate and the cell module to bond the base plate and the cell module;

and the second adhesive is arranged between the cover plate and the cell module so as to bond the cover plate and the cell module.

10. The battery pack of any one of claims 1 to 8, wherein the cover plate is a liquid cooling plate to cool the battery cell module.