阅读说明：本技术 一种用于电池包的电池箱体及电池包 (Battery box body for battery pack and battery pack ) 是由 黄纪伟 师绍纯 晁东海 曲伟 刘保嘉 于 2020-04-23 设计创作，主要内容包括：本发明提供了一种电池箱体和电池包,电池箱体包括箱体框架和与箱体框架固定连接的箱体底部,箱体底部为两层结构,包括直接密封连接的上层平板和下层冲压板,下层冲压板设置有冲压形成的凹槽,以形成液冷系统的流体通道。本发明的电池箱体的箱体底部为集成的两层结构的液冷系统,使得电池包内部没有快插接头及管路连接,完全避免了电池包内部漏液的风险,提高了电池包的安全性及可靠性。并且,箱体底部与箱体框架直接焊接,大大提高了生产装配效率。进一步地,使用了本发明电池箱体的电池包,节省了分离式液冷系统组装过程中系统装配及测试所需的工时。(The invention provides a battery box body and a battery pack, wherein the battery box body comprises a box body frame and a box body bottom fixedly connected with the box body frame, the box body bottom is of a two-layer structure and comprises an upper flat plate and a lower stamped plate which are directly and hermetically connected, and the lower stamped plate is provided with a groove formed by stamping so as to form a fluid channel of a liquid cooling system. The bottom of the battery box body is provided with the integrated liquid cooling system with the two-layer structure, so that the battery pack is not internally connected with a quick connector and a pipeline, the risk of liquid leakage inside the battery pack is completely avoided, and the safety and the reliability of the battery pack are improved. And moreover, the bottom of the box body is directly welded with the box body frame, so that the production and assembly efficiency is greatly improved. Furthermore, the battery pack using the battery box body saves the working hours required by system assembly and test in the assembly process of the separated liquid cooling system.)

1. The utility model provides a battery box for battery package, the battery box include the box frame and with box frame fixed connection's bottom half, its characterized in that, the bottom half is two-layer structure, including direct sealing connection's upper strata flat board and lower floor's punching press board, lower floor's punching press board is provided with the recess that the punching press formed to form the fluid passage of liquid cooling system.

2. The battery box for a battery pack, according to claim 1, wherein the box bottom comprises at least two upper flat plates and/or at least two lower stamped plates arranged in parallel, the box bottom further comprises a stamped connector, each lower stamped plate is in fluid communication with the stamped connector, and the stamped connector is in sealing connection with the upper flat plates and/or the box frame.

3. The battery case for a battery pack, according to claim 1, wherein the case bottom comprises at least two of the upper flat plates and/or at least two of the lower stamped plates arranged in parallel, each of the lower stamped plates being directly and sealingly connected with the upper flat plate to form a respective independent fluid channel.

4. The battery case for a battery pack, as set forth in claim 2 or 3, wherein said fluid passage comprises a flow dividing passage and a return passage, said flow dividing passage communicates with a fluid inlet of said liquid cooling system, said return passage communicates with a fluid outlet of said liquid cooling system, and said fluid inlet and said fluid outlet are provided in the same or different lower stamped plates.

5. The battery case for a battery pack, according to claim 4, wherein the fluid inlet and the fluid outlet are disposed on the same side of the same lower stamped plate, the flow dividing channel and the return channel are connected by a U-shaped connecting section, and the flow dividing channel and the return channel are serpentine narrow channels parallel to each other.

6. The battery box body for the battery pack according to claim 5, wherein the flow dividing channel and the return channel are each partitioned by at least two flow channel branches parallel to each other, each flow channel branch of the flow dividing channel is communicated through a first communicating port, each flow channel branch of the return channel is communicated through a second communicating port, and each flow channel branch is provided with a protruding point formed by punching.

7. The battery case for a battery pack according to claim 2 or 3, wherein the battery case includes a connector mounting end plate fixedly connected with the case frame to connect an external connector.

8. The battery box for battery packs as claimed in claim 2 or 3, further comprising a shielding plate located below the bottom of the box and connected to the box frame.

9. The battery box body for the battery pack as claimed in claim 8, wherein elastic foam is laid between the protection plate and the bottom of the box body.

10. The battery case for a battery pack according to claim 2 or 3, further comprising a battery pack upper cover connected with the case frame to seal the battery case.

11. A battery pack comprising a battery case and a battery module mounted inside the battery case, wherein the battery case is the battery case according to any one of claims 1 to 10.

Technical Field

The invention relates to the technical field of new energy batteries, in particular to the technical field of new energy battery cooling, and more particularly relates to a battery box with a liquid cooling system and a battery pack comprising the battery box.

Background

The performance, service life and safety of a power battery of a new energy automobile have great influence on the heat productivity of a battery module of a battery pack during working, and in recent years, with the increasing requirements of the new energy automobile on high-power charge and discharge performance and environmental adaptability, the search for an effective and reliable battery pack thermal management system becomes the key point of current work. The common cooling modes of the power battery pack include natural cooling, air cooling, liquid cooling and direct refrigerant cooling, wherein a liquid cooling system is widely applied to domestic and foreign mainstream vehicle enterprises due to the advantage of high cooling efficiency.

The battery pack liquid cooling system in the market at present usually adopts a separated liquid cooling system, as shown in fig. 1, a quick connector and a pipeline are usually adopted between a liquid cooling plate and a liquid cooling plate of the separated liquid cooling system, and the liquid cooling plate is connected with a water inlet and a water outlet through the pipeline. In case the coolant liquid reveals in the battery package in a large number, will arouse the circuit short circuit to take place unexpected danger to, the condensation in the box that the moisture volatilizees or sealed inefficacy caused in the coolant liquid also can lead to insulation fault, has influenced the security and the customer experience of whole car, and in addition, disconnect-type liquid cooling plate pipe connection is complicated, and is with high costs and machining efficiency hangs down.

Disclosure of Invention

The invention aims to overcome the defects in the prior art, provides a battery box body for a battery pack and the battery pack, solves the problem of liquid leakage of a liquid cooling system pipeline of the battery pack, and improves the system integration level.

According to a first aspect of the invention, a battery box for a battery pack is provided, the battery box comprises a box frame and a box bottom fixedly connected with the box frame, the box bottom is of a two-layer structure and comprises an upper flat plate and a lower stamped plate which are directly and hermetically connected, and the lower stamped plate is provided with a groove formed by stamping so as to form a fluid channel of a liquid cooling system.

According to an optional embodiment of the invention, the tank bottom comprises at least two upper flat plates and/or at least two lower stamped plates arranged in parallel, the tank bottom further comprises a stamped connector, each lower stamped plate is in fluid communication with the upper flat plate and/or the tank frame through the stamped connector, and the stamped connector is in sealing connection with the upper flat plate and/or the tank frame.

According to an alternative embodiment of the invention, the tank bottom comprises at least two of the upper flat plates and/or at least two of the lower stamped plates arranged in parallel, each of the lower stamped plates being in direct sealing connection with the upper flat plate to form a respective independent fluid channel.

According to an alternative embodiment of the present invention, the fluid passage includes a flow dividing passage and a return passage, the flow dividing passage is communicated with the fluid inlet of the liquid cooling system, the return passage is communicated with the fluid outlet of the liquid cooling system, and the fluid inlet and the fluid outlet are disposed on the same or different lower stamping plates.

According to an alternative embodiment of the invention, the fluid inlet and the fluid outlet are arranged on the same side of the same lower punch plate, the flow dividing channel and the return channel are connected by a U-shaped connecting section, and the flow dividing channel and the return channel are serpentine narrow channels parallel to each other.

According to an optional embodiment of the present invention, the flow dividing channel and the return channel are each separately provided with at least two flow channel branches parallel to each other, each flow channel branch of the flow dividing channel is communicated through a first communicating port, each flow channel branch of the return channel is communicated through a second communicating port, and each flow channel branch is provided with a protruding point formed by stamping.

According to an alternative embodiment of the invention, the battery case includes a connector mounting end plate fixedly connected with the case frame to connect an external connector.

According to an alternative embodiment of the present invention, the battery case further includes a shielding plate positioned below the bottom of the case and coupled to the case frame.

According to the optional embodiment of the invention, elastic foam is paved between the protection plate and the bottom of the box body.

According to an alternative embodiment of the present invention, the battery case further includes a battery pack upper cover coupled to the case frame to seal the battery case.

According to a second aspect of the present invention, a battery pack is provided, which includes a battery case and a battery module mounted inside the battery case, wherein the battery case is the battery case according to the first aspect of the present invention.

The invention has the following beneficial technical effects:

the integrated liquid cooling system is directly formed at the bottom of the battery box body, so that the liquid leakage risk of the liquid cooling pipeline in the battery pack is effectively avoided. Specifically, the bottom of the box body is of a two-layer structure comprising an upper flat plate and a lower stamped plate, the two-layer structure is hermetically connected with a flow dividing channel and a flow return channel which form a liquid cooling system, and a fluid inlet and a fluid outlet which are respectively communicated with the flow dividing channel and the flow return channel are also integrated at the bottom of the box body, so that the design of no pipeline connection and no quick connector in the battery pack is realized, and the safety and the reliability of the battery pack are improved. Furthermore, the integration level of the battery box body is high, the subsequent production and assembly efficiency is greatly improved, the production process is simplified, and errors caused by the production and assembly process are reduced.

Drawings

Other features and advantages of the present invention will be better understood by the following detailed description of the preferred embodiments when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof, and wherein:

fig. 1 shows a schematic diagram of a split-cell liquid cooling system in a prior art design;

FIG. 2 illustrates a perspective view of a case frame of a battery case according to an embodiment of the present invention;

FIG. 3 shows a top view of the bottom of the battery case according to one embodiment of the present invention;

FIG. 4 shows a partial cross-sectional view of section A-A of FIG. 3;

FIG. 5 illustrates a top view of a cabinet frame fixedly attached to a cabinet bottom according to one embodiment of the present invention;

FIG. 6 shows a top view of the bottom of the battery case according to another embodiment of the present invention;

FIG. 7a shows a cross-sectional view of section B-B shown in FIG. 6; FIG. 7b shows a cross-sectional view of section C-C shown in FIG. 6; FIG. 7c shows a partial enlarged schematic view of region D shown in FIG. 6;

FIG. 8a shows an inside view of a connector mounting end plate according to one embodiment of the present invention, and FIG. 8b shows an outside view of the connector mounting end plate;

FIG. 9 is a schematic view illustrating a coupling relationship of a tank frame, a tank bottom and a shielding plate according to an embodiment of the present invention;

fig. 10 shows a schematic view of a battery pack including a battery case and battery modules mounted inside the battery case according to the embodiment of fig. 6;

FIG. 11 shows a schematic view of the welding of the bottom of the battery case to the case frame according to the embodiment of FIG. 6;

figure 12 shows a top view of a fender according to one embodiment of the invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In an alternative embodiment, as shown in fig. 2-5, the battery case 1 for the battery pack includes a case frame 11 and a case bottom 12 fixedly connected to the case frame 11, and specifically, the case bottom 12 and the case frame 11 are fixedly connected by friction stir welding (FSW welding technology), so as to provide a protection level of IP67 or above to the inside of the battery pack. As shown in fig. 3 and 4, the tank bottom 12 has a two-layer structure, which includes an upper flat plate 121 and a lower stamped plate 122 directly and hermetically connected, wherein the lower stamped plate 122 is provided with a stamped groove 1220 to form a fluid passage of the liquid cooling system.

Specifically, the upper flat plate 121 and the lower stamped plate 122 are each an aluminum plate, and the upper flat plate 121 and the lower stamped plate 122 are sealingly joined by brazing, thereby forming a sealed fluid chamber.

In an alternative embodiment, the tank bottom 12 comprises at least two upper flat plates 121 and/or at least two lower stamped plates 122 arranged in parallel. As shown in fig. 3 and 9, the case bottom 12 includes two upper flat plates 121 and two lower stamped plates 122 (not visible in the drawings) arranged in parallel, and the lower stamped plates 122 correspond to the upper flat plates 121 one to one, and with this structural arrangement, since the case frame 11 is provided with the beams 111 (shown in fig. 2), on one hand, there is no need for cooling at the positions of the beams 111, and on the other hand, the weight of the case bottom 12 can be reduced, thereby reducing the weight of the battery case 1.

For the design of at least two lower stamped plates 122, as shown in fig. 3, the bottom 12 of the box body further comprises stamped connectors 123, each lower stamped plate 122 is in fluid communication with the other lower stamped plate 122 through the stamped connectors 123, specifically, the stamped connectors 123 are also provided with grooves forming fluid channels and are open at the upper part, and are in a sheet structure similar to a U shape when viewed from the side. At this time, the number of the upper flat plates 121 may be one or correspond to the number of the lower stamped plates 122, for a whole upper flat plate 121, the stamped connecting member 123 may be directly and hermetically connected with the upper flat plate 121, and for an upper flat plate 121 whose number corresponds to the lower stamped plate 122, the stamped connecting member 123 may be directly and hermetically connected with the beam 111 of the box frame 11, optionally, the hermetically connected manner is welding. Regardless of how the punch connectors 123 are connected, fluid communication is ensured between the grooves 1220 of each lower punch plate 122.

In an alternative embodiment, as shown in fig. 3, the fluid passages include a bypass passage 1221 and a return passage 1222, wherein the bypass passage 1221 communicates with a fluid inlet 1223 of the liquid cooling system, the return passage 1222 communicates with a fluid outlet 1224 of the liquid cooling system, and optionally the fluid inlet 1223 and the fluid outlet 1224 are provided on different lower punch plates 122. Further alternatively, the fluid inlet 1223 and the fluid outlet 1224 are integrated directly on the lower layer ram plate 122, and as shown in fig. 2-3, the fluid inlet 1223 and the fluid outlet 1224 are in fluid communication with the inlet fitting 112 and the outlet fitting 113 of the tank frame 11 via the connection fitting 124, wherein the connection fitting 124 is connected to the tank frame 11, for example by welding.

In an alternative embodiment, for at least two lower punch plates 122, the number of upper plate 121 may be one or corresponding to the number of lower punch plates 122, and in the embodiment shown in fig. 6-7, unlike the embodiment shown in fig. 3, each lower punch plate 122 ' is directly connected with the upper plate 121 ' in a sealing manner to form a separate fluid channel, that is, each lower punch plate 122 ' is punched to form a fluid inlet and a fluid outlet. For a whole upper flat plate 121 ', all the lower punching plates 122 ' are hermetically connected with the upper flat plate 121 ' and then connected with the box frame 11, and for the upper flat plates 121 ' the number of which corresponds to that of the lower punching plates 122 ', all the lower punching plates 122 ' are hermetically connected with the corresponding upper flat plate 121 ' and then directly connected with the box frame 11.

For each independent fluid channel, as shown in fig. 6-7, the fluid inlet 1223 ' and the fluid outlet 1224 ' are disposed on the same side of the same lower punch plate 122 ', the bypass channel 1221 ' and the return channel 1222 ' are connected by a U-shaped connecting segment 1225, and the bypass channel 1221 ' and the return channel 1222 ' are serpentine narrow channels parallel to each other.

Specifically, the flow dividing channel 1221 'and the return channel 1222' are both partitioned into at least two flow channel branches parallel to each other, as shown in fig. 6 and 7a, the flow dividing channel 1221 'is partitioned into two flow channel branches, the return channel 1222' is also partitioned into two flow channel branches, and the flow in the flow dividing channel 1221 'and the return channel 1222' is communicated only at the U-shaped connecting segment 1225. The flow path branches of the branch flow path 1221 'are communicated with each other through the first communication port 1226, the flow path branches of the return flow path 1222' are communicated with each other through the second communication port 1227, and the first communication port 1226 and the second communication port 1227 enhance turbulent flow in the flow path branches of the branch flow path 1221 'and the flow path branches of the return flow path 1222', respectively, thereby improving heat exchange efficiency. As shown in fig. 7a to 7c, each flow channel branch is provided with a stamped convex point 1228, and the convex point 1228 is formed on the stamped groove 1220, so that the heat exchange efficiency is further improved.

In an alternative embodiment, as shown in fig. 2, the battery case 1 further includes a connector mounting end plate 13, and the connector mounting end plate 13 is fixedly connected with the case frame 11 to connect external connectors, including a high voltage connector and a low voltage connector. Specifically, the connector mounting end plate 13 is integrally formed by low-pressure aluminum casting, and the connector mounting end plate 13 and the case frame 11 are connected by cold metal transfer welding (CMT welding technique). The connector mounting end plate 13 is adopted to connect the external connector, so that the problems of complex sealing design, high failure probability and insufficient structural strength caused by the opening of the box frame are solved. Fig. 8a shows a schematic view of the connector mounting end plate 13 viewed from the inside of the case frame 11, and fig. 8b shows a schematic view of the connector mounting end plate 13 viewed from the outside of the case frame 11.

In an alternative embodiment, the cabinet frame 11 is fabricated using 6061-T6 extrusions and cold metal transfer welding, has good weather resistance and high mechanical strength, and is lightweight.

In an alternative embodiment, as shown in fig. 9, the battery case 1 further includes a shielding plate 14, and the shielding plate 14 is located below the case bottom 12 and is connected to the case frame 11. Alternatively, the battery case body 1 may be formed without the protection plate 14, and the protection plate 14 provides a bottom protection function for the battery pack. Specifically, the protection plate 14 is formed by stamping a thin steel plate to form a plurality of stamped portions, which can perform a good protection function, and is connected to the tank frame 11 through a Flow Drilling and Screwing (FDS) process.

Fig. 10 shows a battery case 1 ' according to a further embodiment, the battery case 1 ' comprising a case frame 11 and a case base 12 ' fixedly connected to the case frame 11. Specifically, the tank bottom 12' is fixedly connected to the tank frame 11 by friction stir welding (FSW welding technique), such as the weld shown in fig. 11. The tank bottom 12 'comprises two upper flat plates 121' and two lower stamped plates 122 'arranged in parallel, in contrast to the illustration of fig. 9, where the two lower stamped plates 122' form two separate fluid channels, which are arranged symmetrically, and where each of the two upper flat plates 121 'is provided with a connection to a fluid inlet 1223' and a fluid outlet 1224 'of the respective lower stamped plate 122'.

In an alternative embodiment, as shown in fig. 10, elastic foam 15 is further laid between the protection plate 14 of the battery box body 1 'and the box body bottom 12', so that not only the overall rigidity of the battery box body can be improved, but also the thermal insulation performance of the battery box body can be greatly improved.

According to the present invention, the battery case 1 further includes a battery pack upper cover (not shown) coupled to the case frame 11 to seal the battery case. Further, the box frame 11 is provided with an upper cover fixing point and a whole vehicle fixing point to realize the sealing of the upper cover and the connection of the battery box body and the whole vehicle, thereby providing mechanical properties such as strength and rigidity of the power battery system. Therefore, according to another aspect of the present invention, there is provided a battery pack including a battery case and a battery module 2 (fig. 10) mounted inside the battery case, wherein the battery case is the above-described battery case according to the embodiment of the present invention. Optionally, as shown in fig. 2, the case frame 11 of the battery case is provided with a plurality of battery module mounting fixing locations, and optionally, as shown in fig. 10, a heat conductive material 3, such as a heat conductive paste, is provided between the battery module 2 and the battery case 1'.

Compared with the prior art, the liquid cooling system with the integrated two-layer structure is arranged at the bottom of the battery box body, so that the quick connector and the pipeline connection are not arranged in the battery pack, the risk of liquid leakage in the battery pack is completely avoided, and the safety and the reliability of the battery pack are improved. And moreover, the bottom of the box body is directly welded with the box body frame, so that the production and assembly efficiency is greatly improved. Furthermore, the battery pack using the battery box body saves the working hours required by system assembly and test in the assembly process of the separated liquid cooling system.

Although some embodiments have been described herein by way of example, various modifications may be made to these embodiments without departing from the spirit of the invention, and all such modifications are intended to be included within the scope of the invention as defined in the following claims.

The particular embodiments disclosed herein are illustrative only and should not be taken as limitations upon the scope of the invention, which is to be accorded the full scope consistent with the claims, as defined in the appended claims. Accordingly, the particular illustrative embodiments disclosed above are susceptible to various substitutions, combinations or modifications, all of which are within the scope of the disclosure.