WO2024174308A1

WO2024174308A1 - Battery modules, battery pack, and vehicle

Info

Publication number: WO2024174308A1
Application number: PCT/CN2023/082080
Authority: WO
Inventors: 陆学中
Original assignee: 东莞精锐电器五金有限公司
Priority date: 2023-02-23
Filing date: 2023-03-17
Publication date: 2024-08-29
Also published as: CN116053650B; CN116053650A

Abstract

Battery modules, a battery pack, and a vehicle. The battery modules comprise a plurality of battery cells connected in sequence in series in a same direction, inner tubes accommodating the plurality of battery cells, and outer tubes located on the outer sides of the inner tubes. Each inner tube and each outer tube define a plurality of hollow cavities surrounding the plurality of battery cells, and a cooling liquid is introduced into the hollow cavities in a series connection direction parallel to the battery cells. According to the battery modules of the present application, the cooling liquid is introduced into the hollow cavities defined by the inner tube and the outer tube in the series connection direction parallel to the battery cells, so that multi-directional heat dissipation can be carried out on the exteriors of the battery cells; the heat dissipation mode achieves uniform heat dissipation and high heat dissipation efficiency, so that the situation that the use of the whole battery pack is affected due to the heat of a single battery cell suddenly increasing and then rapidly spreading to an adjacent battery cell can be avoided.

Description

Battery modules, battery packs and vehicles

Technical Field

The present application relates to the field of battery technology, and in particular to a battery module, a battery pack and a vehicle.

Background Art

As the new energy crisis becomes increasingly serious, traditional fuel vehicles are gradually replaced by new energy vehicles. As a type of new energy vehicle, hybrid or pure electric vehicles are developing particularly rapidly. With the increasing maturity and development of electric vehicle battery pack technology, electric vehicles will surely become the main trend of the future development of the automotive industry. However, there are also some problems with the use of electric vehicle battery packs, such as the thermal management of battery packs. Due to the complex operating conditions and environment of the battery pack, if the heat in the battery pack cannot be quickly transferred outside the battery pack, the temperature in the battery pack will become higher and higher, which will eventually directly affect the service life and safety performance of the battery pack. Furthermore, electric vehicles are used in harsh environments and have high frequency of use, and the requirements for the battery pack and the power battery inside are more stringent and demanding. It is necessary to ensure that the temperature field in the battery pack and the power battery is uniform. Since the battery pack has high requirements for the external protection level and seismic performance, the current technology is not enough to meet its requirements. Therefore, solving the thermal problem of the battery pack has become an urgent problem for manufacturers.

Traditional battery packs use air cooling, which requires heat convection inside and outside the battery pack. Since the entire battery pack is difficult to seal, this method will cause air convection inside and outside and introduce dust, impurities and water vapor. Therefore, it brings the risk of accelerated aging of the high and low voltage connection parts, electronic components, high-voltage devices and battery cells inside the battery pack, the risk of failure of electronic components and high-voltage devices, and also poses a huge threat to the safety performance of the battery pack.

The existing thermal management mode usually sets a cooling pipe or a cooling plate in the battery pack or battery module, and coolant is passed through the cooling pipe or the cooling plate, and the heat is released to the outside through the heat exchange of the coolant to perform thermal management of the battery pack or battery module. Although this thermal management mode can alleviate the heat dissipation problem of the battery pack to a certain extent, the cooling pipe and the cooling plate are usually set in the frame structure of the battery pack and are close to the battery pack. End plates and side plates are either arranged between adjacent battery modules or adjacent battery cells. This type of thermal management mode has the problem of uneven heat dissipation and cannot effectively dissipate the heat of the battery pack. Especially when the heat of a single battery cell increases sharply, it can easily spread quickly to the adjacent battery cells and affect the use of the entire battery pack.

Application Contents

The purpose of the present application is to provide a battery module, a battery pack and a vehicle. The battery module can achieve 360° all-round heat dissipation, thereby effectively managing the thermal management of the battery pack and contributing to the rapid development of electric vehicles.

To achieve the above-mentioned objectives, the first aspect of the present application provides a battery module, comprising a plurality of battery cells connected in series in the same direction, an inner tube for accommodating the plurality of battery cells, and an outer tube located outside the inner tube, the inner tube and the outer tube together form a plurality of through cavities surrounding the plurality of battery cells, and a coolant flows through the through cavities in a direction parallel to the connection direction of the battery cells.

In the battery module of the present application, a plurality of through cavities formed by the inner tube and the outer tube pass coolant along a direction parallel to the series connection direction of the battery cells, which can dissipate heat on the outside of the battery cells in multiple directions. This method dissipates heat evenly and has high heat dissipation efficiency, and can prevent a sharp increase in heat in a single battery cell from spreading rapidly to adjacent battery cells and affecting the use of the entire battery pack.

As a technical solution of the present application, the inner tube and the outer tube are combined to form a through cavity surrounding the plurality of battery cells. This structure can achieve 360° all-round heat dissipation with high heat dissipation efficiency.

As a technical solution of the present application, the outer tube extends toward the inner tube to form a plurality of reinforcing ribs, and the plurality of reinforcing ribs are suspended toward one end of the inner tube. The provision of the reinforcing ribs can improve the strength of the battery module.

As a technical solution of the present application, the inner tube and the outer tube are combined to form a plurality of spaced through cavities surrounding the plurality of battery cells.

As a technical solution of the present application, the outer tube extends toward the inner tube to form a plurality of reinforcing ribs connected to the inner tube. This structure connects the outer tube and the inner tube by the reinforcing ribs, so the outer tube and the inner tube can simultaneously provide strength protection for the battery cell.

As a technical solution of the present application, the battery cell is a cylindrical battery, and the inner tube and the outer tube are both hollow circular tubes.

As a technical solution of the present application, the inner tube and the outer tube have the same central axis of rotation.

As a technical solution of the present application, the battery cell and the inner tube are clearance-matched.

As a technical solution of the present application, the outer tube is provided with a plurality of strip-shaped protruding teeth protruding outwardly and extending along the series connection direction of the battery cells.

As a technical solution of the present application, the cross-sectional profile of the strip-shaped convex teeth is arc-shaped or "∧"-shaped.

The second aspect of the present application provides a battery pack, comprising a first cover body, a second cover body placed under the first cover body and the aforementioned battery module, wherein the direction from the first cover body to the second cover body is defined as a first direction, the first cover body and the second cover body are enclosed to form a plurality of isolated through-hole accommodating cavities, the central axis of the through-hole accommodating cavities is perpendicular to the first direction, each of the through-hole accommodating cavities contains a single battery module, and the central axis of the through-hole accommodating cavities is parallel to the series connection direction of the battery cells.

The battery module used in the battery pack of the present application can dissipate heat 360° in all directions on the outside of the battery cell, so the heat dissipation efficiency of the battery pack is also improved. The battery module is accommodated in a through-concentric accommodating cavity formed by the first cover body and the second cover body, that is, the outside of the battery module is wrapped by the first cover body and the second cover body, so the risk of shaking, moving, and damage to the battery module during use can be reduced. At the same time, the arrangement of the first cover body and the second cover body can improve the strength of the entire battery pack. The serial connection direction of the battery cell is parallel to the central axis of the through-concentric accommodating cavity and perpendicular to the first direction, so the battery cell is placed on its side in the battery pack, which can alleviate the force on the battery cell, thereby increasing the usability of the battery cell and the battery module. At the same time, placing the battery cell on its side can facilitate the subsequent installation of wiring harness isolation plates, BMS, etc.

As a technical solution of the present application, the first cover body is provided with a plurality of isolated first grooves facing the second cover body, and the second cover body is provided with a plurality of second grooves corresponding to the positions of the first grooves facing the first cover body, and the corresponding first grooves and the second grooves enclose the through-hole accommodating cavity.

As a technical solution of the present application, the cross-sectional shape of the first groove in the first direction is semicircular, and the cross-sectional shape of the second groove in the first direction is semicircular.

As a technical solution of the present application, the battery module and the cavity wall gap of the through-hole accommodating cavity are matched.

As a technical solution of the present application, the third aspect of the present application provides a battery pack, comprising a plurality of the aforementioned battery modules, wherein adjacent battery modules are overlapped by the strip-shaped protruding teeth.

The battery pack of the present application can be fixed by overlapping the bar-shaped protruding teeth on the battery module to prevent This method can avoid the use of the first cover and the second cover to form a receiving cavity for fixing. By omitting the first cover and the second cover, the volume and weight energy density of the battery pack can be increased, and the production process is also improved accordingly.

A fourth aspect of the present application provides a vehicle, including a vehicle body and a vehicle base, wherein a battery cluster is installed in the vehicle base, and the battery cluster includes a plurality of the aforementioned battery packs.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a three-dimensional diagram of a battery pack according to an embodiment of the present application.

FIG. 2 is a partial three-dimensional perspective view of an embodiment of a battery pack of the present application.

FIG. 3 is a partial top perspective view of an embodiment of a battery pack of the present application.

FIG. 4 is a partial side view of an embodiment of a battery pack of the present application.

FIG. 5 is a partial exploded view of FIG. 4 .

FIG. 6 is a variation diagram of FIG. 4 .

FIG. 7 is a three-dimensional perspective view of an embodiment of a battery module of the present application.

FIG. 8 is a front perspective view of an embodiment of a battery module of the present application.

FIG. 9 is a variation diagram of FIG. 7 .

FIG. 10 is a side cross-sectional view of an embodiment of a battery module of the present application.

FIG. 11 is a variation of FIG. 10 .

FIG. 12 is another variation of FIG. 10 .

FIG. 13 is another variation of FIG. 10 .

Component Symbols
100-battery pack; 10-first cover; 11-first groove; 30-second cover; 31-second groove; 50-battery module; 51-battery cell; 53-inner tube; 55-outer tube; 551-strip convex teeth; 57-reinforcement ribs; 71-first total output terminal; 73-second total output terminal; 91-water inlet; 93-water outlet; D1-first direction; D2-serial direction of battery cells; S1-through accommodating cavity; S2-through cavity

DETAILED DESCRIPTION

In order to better illustrate the purpose, technical solution and beneficial effects of this application, the following is a detailed description of the present invention with reference to the accompanying drawings. It should be noted that the structures shown in the following figures are further explanations of the present application and should not be regarded as limitations of the present application.

The battery pack of the present application can be used in electric vehicles, lawn mowers, energy storage power stations and other power facilities, especially in electric vehicles. When used in vehicles, one or more battery packs can be closely arranged in a matrix to form a battery cluster and installed in the vehicle base under the vehicle body.

The battery pack of the present application will be further described below in conjunction with the accompanying drawings. As shown in Figures 1 to 5, the battery pack 100 includes a first cover body 10, a second cover body 30 placed below the first cover body 10, and a battery module 50. A plurality of battery modules 50 are arranged in a matrix and then lead out a first total output terminal 71 and a second total output terminal 73. The pole end on the battery module 50 can be connected to the total output terminal through a connecting piece and other components to achieve electrical output. The specific connection can be a common method in the industry, which is not the focus of protection of this application, so it will not be repeated here. The battery pack 100 can be provided with a water inlet 91 and a water outlet 93 at the lead-out end of the first total output terminal 71 and the second total output terminal 73, and the water inlet 91 and the water outlet 93 are connected to the cooling components in the battery module 50. The first cover body 10 and the second cover body 30 can be matched and connected with the components of the vehicle base, or directly used as the chassis of the vehicle base. The direction from the first cover body 10 to the second cover body 30 is defined as the first direction D1. The first cover body 10 and the second cover body 30 enclose a plurality of isolated through-containment cavities S1, the central axis of the through-containment cavity S1 is perpendicular to the first direction D1, and a single battery module 50 is placed in each through-containment cavity S1. The through-containment cavity S1 refers to a through-containment structure inside, which is connected to the outside, and the central axis of the through-containment cavity S1 is parallel to the serial connection direction D2 of the battery cells 51. The battery module 50 is placed in the through-containment cavity S1 enclosed by the first cover body 10 and the second cover body 30, that is, the outside of the battery module 50 is wrapped by the first cover body 10 and the second cover body 30, so the risk of shaking, moving, damage, etc. of the battery module 50 during use can be reduced, and at the same time, the arrangement of the first cover body 10 and the second cover body 30 can improve the strength of the entire battery pack 10. The serial connection direction D2 of the battery cells 51 is parallel to the central axis of the through-hole accommodating cavity S1 and perpendicular to the first direction D1 . Therefore, the battery cells 51 are placed sideways in the battery pack 10 , which can alleviate the stress on the battery cells 51 and increase the usability of the battery cells 51 and the battery module 50 .

Further, as shown in FIGS. 4 and 5 , the first cover 10 is provided with a plurality of isolated first grooves 11 facing the second cover 30. The second cover 30 is provided with a plurality of second grooves 31 facing the first cover 10 corresponding to the positions of the first grooves 11. The corresponding first grooves 11 and second grooves 31 are enclosed to form a through-hole receiving cavity S1. The gap between the battery module 50 and the cavity wall of the through-hole receiving cavity S1 is matched, thereby improving the heat dissipation efficiency and volume space utilization. Utilization rate.

Continuing with FIGS. 7 to 13 , the battery module 50 includes a plurality of battery cells 51 connected in series in the same direction, an inner tube 53 for accommodating the plurality of battery cells 51, and an outer tube 55 located outside the inner tube 53. The inner tube 53 and the outer tube 55 enclose a plurality of through cavities S2 surrounding the plurality of battery cells 51. A coolant flows through the inner edge of the through cavity S2 parallel to the connection direction D2 of the battery cells 51. The through cavity S2 is provided with openings at both ends parallel to the connection direction D2 of the battery cells 51. The coolant flows in from the opening at one end and flows out from the opening at the other end, thereby performing heat exchange and dissipating heat. The coolant flows through the inner edge of the through cavity S2 enclosed by the inner tube 53 and the outer tube 55 parallel to the connection direction D2 of the battery cells 51, and the outside of the battery cells 51 can be cooled in multiple directions. This method dissipates heat evenly and has high heat dissipation efficiency. The through cavity S2 is connected to the water inlet 91 and the water outlet 93. The coolant enters from the water inlet 91 and is diverted to each through cavity S2. After flowing through each through cavity S2, it is gathered and flows out of the battery pack 100 through the water outlet 93. A diverter plate and a collector plate may be respectively provided in the battery pack 100 to realize the diversion and collection of the coolant at both ends of the through cavity S2. The diverter plate and the collector plate may be common structures on the market, which are not the focus of this application, so they will not be described here. The coolant may be, but is not limited to, a water/ethylene glycol mixed solution, silicone oil or silicone grease. Except for the electrical connection between the battery modules 50 of the present application, they can be independently integrated into the battery pack, so the abnormal battery module 50 can be repaired and replaced separately during use. In actual use, an explosion-proof valve, a PTC temperature control device, etc. can be installed at one end of the battery module 50 to provide safety protection and abnormal monitoring for the single battery module 50. Each battery cell 51 can be equipped with or not equipped with an explosion-proof valve, a PTC temperature control device, etc. according to actual conditions.

The battery cell 51 of the present application may be a square battery, an arc-shaped battery, a blade battery or a cylindrical battery. Preferably, the battery cell 51 is a cylindrical battery, and the inner tube 53 and the outer tube 55 are both hollow circular tubes. For cylindrical batteries, if this heat dissipation method is adopted, the heat dissipation efficiency is higher, and the occupied volume of the inner tube 53 and the outer tube 55 is lower, and it is easier to pass the coolant in the through cavity S2. For the battery pack 100 in which the battery cell 51 is a cylindrical battery, the cross-sectional shape of the first groove 11 in the first direction D1 is semicircular, and the cross-sectional shape of the second groove 31 in the first direction D1 is semicircular. Of course, based on the battery cell 51 being a square battery, an arc-shaped battery or a blade battery or other shapes of batteries, the cross-sectional shape of the first groove 11 and the second groove 31 in the first direction D1 is also set to a shape corresponding to the battery cell 51, thereby improving the heat dissipation efficiency of the battery pack 100.

The inner tube 53 and the outer tube 55 in the battery module 50 of the present application can be of various structures. As shown in FIG10 , the inner tube 53 and the outer tube 55 enclose a through cavity S2 surrounding a plurality of battery cells 51. The body S2 is a closed annular structure surrounding multiple battery cells 51. This structure can achieve 360° all-round heat dissipation with high heat dissipation efficiency. Alternatively, as shown in FIG. 11, the outer tube 55 extends toward the inner tube 53 to form multiple reinforcing ribs 57, and the multiple reinforcing ribs 57 are suspended toward one end of the inner tube 53. The provision of the reinforcing ribs 57 can improve the strength of the battery module 50. Alternatively, as shown in FIG. 12, the inner tube 53 and the outer tube 55 enclose a plurality of spaced through cavities S2 surrounding multiple battery cells 51. The outer tube 55 extends toward the inner tube 53 to form a plurality of reinforcing ribs 57 connected to the inner tube 53, so it is divided into a plurality of through cavities S2. The number of through cavities S2 can be set according to actual needs, which is required to ensure that a certain strength is achieved without affecting the flow of the coolant. This structure can process the inner tube 53 and the outer tube 55 in one piece, so the production efficiency is high. In addition, this structure connects the outer tube 55 and the inner tube 53 by means of the reinforcing rib 57, so the strength of the battery cell 51 can be protected at the same time. The material of the inner tube 53 and the outer tube 55 can be metal materials such as aluminum, copper, stainless steel, or thermal insulation materials such as polyurethane foam, polystyrene board, EPS, XPS, phenolic foam, polypropylene, ceramic, etc. The material of the inner tube 53 and the outer tube 55 can be the same or different. If the inner tube 53 and the outer tube 55 are processed in one piece, the same material is also selected, preferably a metal material such as aluminum, copper, stainless steel, etc. If it is not processed in one piece, the outer tube 55 is selected to have stronger thermal insulation and the inner tube 53 is selected to have stronger thermal conductivity. In other words, the battery module 50 has a higher strength by adopting a structure with reinforcing ribs 57 as shown in Figures 11 and 12. Therefore, if the strength requirement of the battery module 50 of the same standard is met, the inner tube 53 and the outer tube 55 with the reinforcing ribs 57 can be set to be thinner, so that the size of the battery module is smaller and the volume energy density of the assembled battery pack 100 is higher.

Furthermore, the outer tube 55 may also have other structures. As shown in FIGS. 9 and 13 , the outer tube 55 is provided with a plurality of strip-shaped protruding teeth 551 extending in the series connection direction D2 of the battery cells 51. The cross-sectional profile of the strip-shaped protruding teeth 551 is arc-shaped or "∧"-shaped. The battery pack 100 formed by integrating the battery modules 50 having the strip-shaped protruding teeth 551 on the outer tube 55 may not be fixed by combining the first cover body 10 and the second cover body 30 into a receiving cavity. As shown in FIG. 6 , the battery pack 100 includes a plurality of battery modules 50, and adjacent battery modules 50 are overlapped by the strip-shaped protruding teeth 551. The battery pack 100 of this structure has a higher volume and weight energy density.

Furthermore, the inner tube 53 and the outer tube 55 have the same central axis of rotation, which can ensure uniform heat dissipation and prevent local heat surges from causing thermal runaway. The battery cell 51 and the inner tube 53 are clearance-matched to improve heat dissipation efficiency and volume space utilization.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present application and are not intended to Please limit the scope of protection. Although the present application has been described in detail with reference to the preferred embodiments, it is not limited to those listed in the embodiments. Those skilled in the art should understand that the technical solution of the present application can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present application.

Claims

A battery module, characterized in that it includes a plurality of battery cells connected in series in the same direction, an inner tube for accommodating the plurality of battery cells, and an outer tube located outside the inner tube, wherein the inner tube and the outer tube together form a plurality of through cavities surrounding the plurality of battery cells, and a coolant flows through the through cavities in a direction parallel to the series connection direction of the battery cells.
The battery module according to claim 1, characterized in that the inner tube and the outer tube are combined to form a through cavity surrounding the plurality of battery cells.
The battery module according to claim 2 is characterized in that the outer tube extends toward the inner tube to form a plurality of reinforcing ribs, and the plurality of reinforcing ribs are suspended toward one end of the inner tube.
The battery module according to claim 1, characterized in that the inner tube and the outer tube enclose a plurality of spaced through cavities surrounding the plurality of battery cells.
The battery module according to claim 4, characterized in that the outer tube extends toward the inner tube to form a plurality of reinforcing ribs connected to the inner tube.
The battery module according to claim 1 is characterized in that the battery cell is a cylindrical battery, and the inner tube and the outer tube are both hollow circular tubes.
The battery module according to claim 1, characterized in that the inner tube and the outer tube have the same central axis of rotation.
The battery module according to claim 1, characterized in that the battery cell and the inner tube are gap-fitted.
The battery module according to claim 1 is characterized in that the outer tube is provided with a plurality of strip-shaped protruding teeth protruding outwardly and extending along the series connection direction of the battery cells.
A battery pack, characterized in that it includes a first cover body, a second cover body placed under the first cover body, and a battery module according to any one of claims 1 to 8, wherein the direction from the first cover body to the second cover body is defined as a first direction, the first cover body and the second cover body are enclosed to form a plurality of isolated through-hole accommodating cavities, the central axes of the through-hole accommodating cavities are perpendicular to the first direction, each of the through-hole accommodating cavities contains a single battery module, and the central axes of the through-hole accommodating cavities are parallel to the series connection direction of the battery cells.
The battery pack according to claim 10 is characterized in that the first cover body is provided with a plurality of isolated first grooves facing the second cover body, and the second cover body is provided with a plurality of second grooves corresponding to the positions of the first grooves facing the first cover body, and the corresponding first grooves and second grooves are enclosed to form the through-hole accommodating cavity.
The battery pack according to claim 11, characterized in that a cross-sectional shape of the first groove in the first direction is semicircular, and a cross-sectional shape of the second groove in the first direction is semicircular.
The battery pack according to claim 10 is characterized in that the battery module and the cavity wall of the through-hole accommodating cavity are gap-matched.
A battery pack, characterized in that it comprises a plurality of battery modules according to claim 9, wherein adjacent battery modules are overlapped by the strip-shaped protruding teeth.
A vehicle, characterized in that it comprises a vehicle body and a vehicle base, wherein a battery cluster is installed in the vehicle base, and the battery cluster comprises a plurality of battery packs according to any one of claims 10 to 14.