CN118017133A

CN118017133A - Battery pack and vehicle

Info

Publication number: CN118017133A
Application number: CN202410253217.7A
Authority: CN
Inventors: 郝钟雅; 肖浪; 王抱恒
Original assignee: Mercedes Benz Group AG
Current assignee: Mercedes Benz Group AG
Priority date: 2024-03-06
Filing date: 2024-03-06
Publication date: 2024-05-10

Abstract

The invention relates to the field of vehicle manufacturing and to a battery pack for a vehicle, in particular an electric vehicle, wherein the battery pack comprises a housing; a battery cell disposed within the housing and configured to provide electrical energy; a getter device is disposed on the housing and configured to be adapted to aspirate moisture in the housing to an exterior of the housing. The invention also relates to a vehicle with a battery pack. The technical scheme of the invention can actively discharge the moisture in the battery pack (the shell) to the outside of the battery pack. In addition, the condensed water is additionally discharged to the outside of the battery pack by providing a corresponding water discharge structure on the bottom of the housing, which further improves the operation safety of the battery pack. By co-acting with the valve means, in particular with the explosion-proof valve already present in the prior art, a particularly reliable moisture discharge is achieved while ensuring that the battery pack remains substantially fluid-tight against the outside of the battery pack in a state other than moisture discharge.

Description

Battery pack and vehicle

Technical Field

The invention relates to the field of power batteries, in particular to a battery pack. The invention also relates to a vehicle with such a battery pack.

Background

With the continuous development of electric vehicles, as a core component of the electric vehicles, higher requirements are also put on the performance, reliability and safety of the power battery pack.

For example, the battery pack may generate heat in an operating state, such as a charged state, of the battery pack. If the inside of the battery pack contains liquid water, the liquid water inside the battery pack may evaporate at high temperature and thus the humidity inside the battery pack is large.

In addition, in the case where the battery pack does not operate, water vapor existing inside the battery pack is liquefied due to a temperature difference between the inside and the outside of the battery pack and condensed water is generated. If the condensed water and moisture cannot be effectively drained from the inside of the battery pack, the humidity inside the battery pack may be excessively high and the bottom of the battery pack case may be "flooded".

Furthermore, the battery pack typically includes an explosion-proof valve or a pressure relief valve, and when the explosion-proof valve or the pressure relief valve is opened, water vapor in the air outside the battery pack may also enter the battery pack, which in turn causes a risk of an increase in humidity inside the battery pack.

Due to the existence of liquid water and water vapor in the battery pack, the electric leakage or short circuit of the battery core, the corrosion of the circuit board, the acceleration of self-discharge of the battery in a high-humidity environment and the like can be caused.

In the prior art, moisture is generally adsorbed inside the battery pack using a water absorbing material such as water absorbing cotton. Once the water absorbing material is saturated, continuous adsorption of moisture cannot be ensured. In addition, since the water absorbing material is saturated, liquid water may also be generated at the water absorbing material. Therefore, it is necessary to disassemble the battery pack and replace the water absorbing material when or before the water absorbing material reaches saturation. However, this in turn increases maintenance costs and disassembly work, and may also affect the air tightness of the battery pack. Thus resulting in low efficiency and poor reliability.

Accordingly, there remains a need for improvements in the art for at least some of the above-mentioned problems.

Disclosure of Invention

Based on this, the present invention proposes an efficient solution that not only overcomes the drawbacks of the prior art solutions, but also allows particularly efficient drainage of the moisture and condensed water inside the battery pack. In addition, the invention can realize particularly favorable drainage of moisture and condensed water only by partial modification, avoids remarkable increase of manufacturing cost and improves the running reliability and safety of the battery pack and the whole vehicle.

According to a first aspect of the present invention, there is provided a battery pack for a vehicle, in particular an electric vehicle, wherein the battery pack comprises:

a housing;

a battery cell disposed within the housing and configured to be adapted to provide electrical energy;

A getter device is disposed on the housing and configured to be adapted to aspirate moisture in the housing to an exterior of the housing.

The basic idea of the invention is to actively remove moisture from the battery pack (housing) to the outside of the battery pack when required by providing a getter device on the housing of the battery pack. In addition, the condensed water is additionally discharged to the outside of the battery pack by providing a corresponding water discharge structure on the bottom of the housing, which further improves the operation safety of the battery pack. By co-acting with the valve arrangement, in particular with the explosion-proof valve already present in the prior art, a particularly reliable moisture discharge is achieved while ensuring that the interior of the battery pack remains substantially fluid-tight from the outside in a state other than moisture discharge.

Advantageous configurations of the solution according to the invention can be obtained from the following alternative embodiments.

According to an alternative embodiment of the battery pack of the present invention, the air sucking means is activated regularly at the same time intervals to activate to suck out the moisture in the case to the outside of the case. Thereby simplifying the construction of the battery pack and reducing the manufacturing cost.

An alternative embodiment of the battery pack according to the invention provides that the battery pack further comprises a humidity sensor arranged inside the housing and configured to detect humidity inside the housing, wherein the suction means are activated to suck out moisture in the housing outside the housing in case a humidity value detected by the humidity sensor exceeds a humidity threshold. This can effectively improve the efficiency of discharging moisture in accordance with the humidity condition inside the battery pack.

An alternative embodiment of the battery pack according to the invention provides that the battery pack further comprises a first valve device arranged on the housing and configured to in an open state fluidly communicate the interior of the housing with respect to the exterior of the housing and in a closed state fluidly seal the interior of the housing with respect to the exterior of the housing, wherein the first valve device opens in case the humidity value detected by the humidity sensor exceeds a humidity threshold. This embodiment ensures a substantially fluid-tight seal of the interior of the battery pack with respect to the exterior of the battery pack in the inactive state of the getter device while a reliable and efficient moisture evacuation is achieved by the co-operation of the first valve device with the getter device.

An alternative embodiment of the battery pack according to the invention provides that the getter device is arranged inside or outside the first valve device.

An alternative embodiment of the battery pack according to the invention provides that the getter device is integrated in the first valve device. This embodiment improves the integration of the battery pack.

According to an alternative embodiment of the battery pack of the invention, a drain opening is constructed in the bottom of the housing, which drain opening is configured to be adapted to drain condensed water from the interior of the housing to the exterior of the housing. This embodiment can ensure that condensed water is discharged to the outside of the battery pack.

An alternative embodiment of the battery pack according to the invention provides that a drain channel is also provided in the bottom of the housing, which drain channel leads to the drain opening. This embodiment reduces the accumulation of condensed water inside the battery pack.

An alternative embodiment of the battery pack according to the invention provides that the bottom of the housing is configured obliquely, in particular with an inclination of 3 to 5 degrees, wherein the drain opening is located at the lowest point of the bottom oblique portion. Thereby reducing accumulation of condensed water inside the battery pack and improving efficiency of condensed water discharge.

According to an alternative embodiment of the battery pack of the present invention, the bottom of the case is manufactured by stamping and chamfering and drawing processes. This embodiment simplifies manufacturing and reduces manufacturing costs.

According to an alternative embodiment of the battery pack according to the invention, a liquid level sensor is also arranged in the bottom of the housing, which liquid level sensor is configured to detect the liquid level of condensed water in the bottom of the housing, and a second valve device is arranged in the drain opening, which second valve device is configured to be opened in case the detected liquid level exceeds a liquid level threshold value for draining condensed water outside the housing. Thereby, condensed water can be discharged in a targeted manner.

According to an alternative embodiment of the battery pack according to the invention, a respective air suction device is arranged on opposite sides of the housing, in particular on both sides in the longitudinal direction of the housing. Thereby improving the efficiency of moisture discharge.

An alternative embodiment of the battery pack according to the invention provides that the air suction device is configured as a fan.

An alternative embodiment of the battery pack according to the invention provides that the first valve device is designed as an explosion-proof valve. This embodiment enables a cost-effective retrofit with existing battery pack arrangements.

An alternative embodiment of the battery pack according to the invention provides that the second valve device is designed as a drain valve.

According to a second aspect of the present invention, a vehicle, in particular an electric vehicle, is provided, wherein the vehicle comprises a battery pack according to one of the above-described embodiments.

Further features of the invention will become apparent from the claims, the drawings, and the description of the drawings. The features and feature combinations mentioned in the above description and those mentioned in the following description of the figures and/or shown only in the figures can be used not only in the respectively specified combination but also in other combinations without departing from the scope of the invention. Accordingly, the following are also considered to be encompassed and disclosed by the present invention: these are not explicitly shown in the figures and are not explicitly explained, but are derived from and result from a combination of separate features from the explained content. The following and combinations of features are also considered disclosed: which does not have all of the features of the original written independent claim. Furthermore, the following and combinations of features are considered to be disclosed, inter alia, by the foregoing: which exceeds or deviates from the combination of features defined in the reference relationships of the claims.

Drawings

The principles, features and advantages of the present invention may be better understood by describing the present invention in more detail with reference to the drawings. In the drawings:

FIG. 1 shows a schematic view of an embodiment of a vehicle according to the present invention;

FIG. 2 shows a schematic top view of one embodiment of a battery pack according to the present invention;

FIG. 3 shows a schematic side view of one embodiment of the battery pack of FIG. 2;

fig. 4 shows a schematic side view of another embodiment of a battery pack according to the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantageous technical effects to be solved by the present invention more apparent, the present invention will be further described in detail with reference to the accompanying drawings and a plurality of exemplary embodiments. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the invention.

In the present specification, for convenience, words such as "middle", "upper", "lower", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, which indicate an azimuth or a positional relationship, are used to describe positional relationships of constituent elements with reference to the drawings, only for convenience of description and simplification of the description, and not to indicate or imply that the apparatus or elements referred to have a specific azimuth, construct and operate in a specific azimuth, and thus should not be construed as limiting the present disclosure. The positional relationship of the constituent elements is appropriately changed according to the direction in which each constituent element is described. Therefore, the present invention is not limited to the words described in the specification, and may be appropriately replaced according to circumstances.

The technical scheme of the invention is described below with reference to the accompanying drawings.

Fig. 1 shows a schematic view of an embodiment of a vehicle 1 according to the invention. In this embodiment, the vehicle 1 is illustratively configured as an electric vehicle and is a passenger vehicle.

As shown in fig. 1, a battery pack 2 is arranged in the chassis below the seat of the vehicle 1. The battery pack 2 is plate-shaped and is used to supply the vehicle 1 with electrical energy. Further, in fig. 1, an XYZ coordinate system is shown, in which the X direction represents the longitudinal direction of the vehicle 1, the Y direction represents the lateral direction of the vehicle 1, and the Z direction represents the vertical direction of the vehicle 1.

Fig. 2 shows a schematic top view of one embodiment of a battery pack 2 according to the present invention.

In this view, the battery pack 2 includes a case 21, which case 21 is cylindrically configured and includes a bottom, four sides, and an open top (open upward in the Z direction in this view) opposite the bottom. After the individual battery cells 22 have been accommodated in the housing 21, the open top of the housing 21 is closed by means of a cover (not shown in this illustration).

According to one embodiment, the housing 21 is made of plastic or metal and its bottom is manufactured by a stamping and chamfer drawing process.

The battery pack 2 further comprises a battery cell 22, the battery cell 22 being arranged within the housing 21 and configured to be adapted to provide electrical energy to the vehicle 2. One cell is only exemplarily labeled with reference numeral "22" in fig. 2, however this is not a limitation of the present invention, and the battery pack 2 may include a plurality of cells 22.

In the present invention, the battery cell 22 may be understood synonymously with "cell".

According to one embodiment, the battery Pack 2 forms a two-stage package (CTP) of a Cell-battery Pack. That is, the battery cells 22 may be directly integrated into the battery pack 2 and the corresponding module integration process may be omitted. In another alternative embodiment, the battery pack 2 forms a Cell-Module-battery pack tertiary package (CTM).

During charging of the battery pack 2, the battery pack 2 may generate heat, and if liquid water is present in the battery pack 2, evaporation of the liquid water causes the humidity inside the battery pack 2 to be excessively high. In the case where the battery pack 2 is not operated, if, for example, the external temperature is low, a temperature difference is generated between the inside of the battery pack 2 and the outside of the battery pack 2, and moisture inside the battery pack 2 condenses and liquid condensed water is generated. If moisture and condensed water cannot be reliably discharged from the inside of the battery pack 2, there are caused effects such as leakage or short circuit of the battery pack 2, corrosion of a circuit board, acceleration of self-discharge of the battery under a high-humidity environment, and the like.

Therefore, in order to solve the problem, according to this embodiment, the battery pack 2 further includes a getter device 23, which getter device 23 is disposed on the case 21 and serves to suck out moisture in the case 21 to the outside of the case 21. In this exemplary embodiment, the suction device 23 is designed as a fan, in particular as a suction fan.

According to one embodiment, the battery pack 2 comprises two getter devices 23, which are arranged on two mutually opposite sides of the housing 21, respectively, in the longitudinal direction of the housing 21 (i.e. in the X-direction). The two suction devices 23 are activated regularly at equal time intervals to suck out the moisture in the casing 21 to the outside of the casing 21, thereby advantageously ensuring that the humidity inside the battery pack 2 is not too high.

According to another embodiment, as shown in fig. 2, the battery pack 2 further includes a humidity sensor 24, and the humidity sensor 24 is disposed inside the case 21 and is used to detect humidity inside the case 21. If the humidity sensor 24 detects that the humidity value inside the housing 21 exceeds the humidity threshold, the air suction means 23 is activated to suck out the moisture in the housing 21 to the outside of the housing 21. This ensures that the humidity in the battery pack 2 is always kept below the humidity threshold, thus ensuring reliable operation of the battery pack 2.

According to another embodiment, the battery pack 2 further comprises a first valve device 25, the first valve device 25 being arranged on the housing 21 and being configured to be adapted to fluidly communicate the interior of the housing 21 with respect to the exterior of the housing 21 in an open state and to fluidly seal the interior of the housing 21 with respect to the exterior of the housing 21 in a closed state. The first valve device 25 is configured as a normally closed valve device and opens in the event that the humidity value detected by the humidity sensor 24 exceeds a humidity threshold.

According to the embodiment of fig. 2, the first valve device 25 is configured as an explosion-proof valve, and the getter device 23 is arranged outside the explosion-proof valve. Thus, in addition to the prior art explosion proof valve opening depending on pressure and/or temperature, in the present invention the explosion proof valve can also be opened based on the humidity value of the humidity sensor 24. Thus, reliable moisture discharge can be achieved by functional expansion using the existing components in the battery pack 2. This not only simplifies the design, but also does not significantly increase the cost.

According to another embodiment, the suction means 23 are integrated in the first valve means 25. Thereby, the integration of the battery pack 2 is improved and a compact design is achieved.

The explosion-proof valve thus cooperates with the air suction device 23, for example a fan, and is activated simultaneously (i.e. the explosion-proof valve is opened and the fan is opened) and the moisture inside the battery pack 2 can be efficiently discharged in case the humidity value detected by the humidity sensor 24 exceeds the humidity threshold. In the event of a low or below a humidity threshold value in the battery pack 2, the explosion protection valve remains normally closed again, which in turn ensures a substantially fluid-tight interior of the battery pack 2 with respect to the outside. Thus, the configuration of the getter device 23 is simplified again.

Fig. 3 shows a schematic side view of an embodiment of the battery pack 2 of fig. 2.

According to this embodiment, a drain opening 26 is constructed at the bottom of the housing 21, the drain opening 26 being for draining condensed water inside the housing 21 to the outside of the housing 21. The bottom of the housing 21 is configured obliquely, for example, at an inclination of 3 degrees to 5 degrees. As shown in fig. 3, the bottom portion of the housing 21 extends obliquely and gradually downward (that is, downward in the Z direction) from the middle portion of the bottom portion of the housing 21 toward both ends of the bottom portion of the housing 21. Therefore, the lowest point of the bottom of the housing 21 is formed at both ends of the bottom of the housing 21. The condensed water located in the bottom of the housing 2 can flow toward both ends through the inclination. Thus, in this embodiment, the drain openings 26 are respectively configured at both ends, i.e., at the lowest point of the bottom. This facilitates drainage of the condensate.

According to one embodiment, a drain groove 27 is also constructed in the bottom of the housing 21, the drain groove 27 leading to a drain opening 26. The drainage of the condensed water is further accelerated by this configuration.

According to one embodiment, a level sensor 29 is also arranged in the bottom of the housing 21, the level sensor 29 being used for detecting the level of condensed water in the bottom of the housing 21. Further, a second valve means 28, such as a drain valve, is arranged in the drain opening 26, the second valve means 28 being adapted to open in case the detected liquid level exceeds a liquid level threshold value to drain condensed water to the outside of the housing 21. This can more accurately drain the condensed water.

Fig. 4 shows a schematic side view of another embodiment of a battery pack 2 according to the invention. Unlike the example in fig. 3, it extends obliquely, gradually rising from the middle portion of the bottom of the housing 21 toward both ends of the bottom of the housing 21. Thus, the lowest point of the bottom of the housing 21 is formed at the middle portion of the bottom of the housing 21. Thus, the drain opening 26 and the second valve device 28 are arranged in this intermediate portion (i.e. at the lowest point). This further simplifies the arrangement and number of drain openings 26 and second valve devices 28 and thereby simplifies manufacture and reduces costs.

Other advantages and alternative embodiments of the invention will be apparent to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details, the representative structures, and illustrative examples shown and described. Rather, various modifications and substitutions may be made by those skilled in the art without departing from the basic spirit and scope of the invention.

Claims

1. A battery pack (2) for a vehicle (1), in particular an electric vehicle (1), wherein the battery pack (2) comprises:

A housing (21);

-a battery cell (22), the battery cell (22) being arranged within the housing (21) and configured to be adapted to provide electrical energy;

-a getter device (23), said getter device (23) being arranged on said housing (21) and configured to be adapted to suck out moisture in said housing (21) to the outside of said housing (21).

2. The battery pack (2) according to claim 1, wherein,

The suction means (23) are activated regularly at equal time intervals to suck out the moisture in the housing (21) to the outside of the housing (21); or alternatively

The battery pack (2) further comprises a humidity sensor (24), the humidity sensor (24) being arranged inside the housing (21) and being configured to be adapted to detect humidity within the housing (21), wherein the suction means (23) is activated to suck out moisture in the housing (21) outside the housing (21) in case a humidity value detected by the humidity sensor (24) exceeds a humidity threshold.

3. Battery pack (2) according to claim 1 or 2, wherein the battery pack (2) further comprises a first valve device (25), the first valve device (25) being arranged on the housing (21) and being configured to be adapted to put the interior of the housing (21) in fluid communication with respect to the exterior of the housing (21) in an open state and to put the interior of the housing (21) in fluid sealing with respect to the exterior of the housing (21) in a closed state, wherein the first valve device (25) is opened in case a humidity value detected by the humidity sensor (24) exceeds a humidity threshold value.

4. A battery pack (2) according to claim 3, wherein,

The suction means (23) is arranged inside or outside the first valve means (25); or alternatively

The suction device (23) is integrated in the first valve device (25).

5. The battery pack (2) according to any one of claims 1 to 4, wherein a drain opening (26) is configured at a bottom of the housing (21), the drain opening (26) being configured to be adapted to drain condensed water inside the housing (21) to outside the housing (21).

6. The battery pack (2) according to claim 5, wherein,

A drain groove (27) is also formed in the bottom of the housing (21), the drain groove (27) leading to the drain opening (26); and/or

The bottom of the housing (21) is configured obliquely, in particular with an inclination of 3 to 5 degrees, wherein the drain opening (26) is located at the lowest point of the bottom oblique portion; and/or

The bottom of the shell (21) is manufactured through a stamping and chamfering die drawing process.

7. Battery pack (2) according to claim 5 or 6, wherein a liquid level sensor (29) is further arranged in the bottom of the housing (21), the liquid level sensor (29) being configured to be adapted to detect the liquid level of condensed water in the bottom of the housing (21), a second valve means (28) being arranged in the drain opening (26), the second valve means (28) being configured to be adapted to open in case the detected liquid level exceeds a liquid level threshold value to drain condensed water outside the housing (21).

8. Battery pack (2) according to any one of claims 1 to 7, wherein one getter device (23) is arranged on each of the opposite sides of the housing (21), in particular on both sides in the longitudinal direction of the housing (21).

9. The battery pack (2) according to any one of claims 1 to 8, wherein,

The suction device (23) is configured as a fan; and/or

The first valve device (25) is designed as an explosion-proof valve; and/or

The second valve device (28) is designed as a drain valve.

10. Vehicle (1), in particular an electric vehicle (1), wherein the vehicle (1) comprises a battery pack (2) according to any one of claims 1 to 9.