Claims:We claim:
1. A battery pack thermal management system (100) for an electric vehicle, the system (100) comprising:
a battery pack (102), said battery pack (102) having a plurality of cells (104) disposed in horizontal and vertical manner;
at least one heat exchange plate (106) disposed in thermal contact with the plurality of cells (104);
at least one layer of thermal interface material (110) interposed between the heat exchange plate (106) and the plurality of cells (104); and
a coolant supply line connected to the heat exchange plate (106),
wherein,
the heat exchange plate (106) is disposed perpendicularly to the plurality of cells (104).
2. The battery pack thermal management system (100) for the electric vehicle as claimed in 1, the system (100) comprising:
the battery pack (102) having a plurality of cells (104) disposed in horizontal and vertical manner;
at least one horizontal heat exchange plate (106a) disposed in thermal contact with a bottom surface of the plurality of cells (104) disposed vertically within the battery pack (102) and defining a first fluid flow region for the coolant; and
at least one vertical heat exchange plate (106b) with both sides disposed in thermal contact with a bottom surface of the plurality of cells (104) disposed horizontally within the battery pack (102) and having a second fluid flow region for the coolant,
wherein,
the horizontal heat exchange plate (106a) and the vertical heat exchange plate (106b) are disposed perpendicular to each other.

3. The battery pack thermal management system (100) as claimed in claim 2, wherein the horizontal heat exchange plate (106a) and the vertical heat exchange plate (106b) are made up of aluminum.

4. The battery pack thermal management system (100) as claimed in claim 1, wherein the heat exchange plate (106) is disposed in at least one of horizontal direction, vertical direction, angular direction and a combination thereof.

5. The battery pack thermal management system (100) as claimed in claim 1, wherein the thermal interface material layer (110) is made up of a material selected from the group consisting of, acrylic sheet, silicon sheet and a combination thereof.

6. The battery pack thermal management system (100) as claimed in claim 1, wherein the horizontal heat exchange plate (106a) and the vertical heat exchange plate (106b) includes at least one of plurality of dimples, depressions, indentations, and fins formed on at least one surface of the horizontal heat exchange plate (106a) and the vertical heat exchange plate (106b).

7. The battery pack thermal management system (100) as claimed in claim 1, wherein the coolant is configured to flow in at least one of U shaped path, straight path, zigzag path and a combination thereof.

8. The battery pack thermal management system (100) as claimed in claim 7, wherein the coolant includes mixture of ethylene glycol and water.

9. The battery pack thermal management system (100) as claimed in claim 1, wherein the heat exchange plate (106) is configured to exchange heat with the coolant of the coolant supply line to cool the battery pack (102).

10. The battery pack thermal management system (100) as claimed in claim 1, wherein the heat exchange plate (106) is configured to exchange heat with the coolant in the coolant supply line to heat the battery pack (102).
11. The battery pack thermal management system (100) as claimed in claim 1, wherein the heat exchange plate (106) comprises an inlet (112) and an outlet (114) which are disposed on same side of the heat exchange plate (106).
12. The battery pack thermal management system (100) as claimed in claim 11, wherein the heat exchange plate (106) is a flat plate.
, Description:TECHNICAL FIELD
[001] The embodiments herein generally relate to a battery pack thermal management system for an electric vehicle (EV), and more particularly to a battery pack thermal management system for an electric vehicle, having heat exchange plates which facilitates in cooling or heating the battery pack of the electric vehicle.
BACKGROUND
[002] Electric vehicles are driven using electric energy. The electric vehicles have advantages of emitting no exhaust gas and making less noise but have not been commercialized as the battery required for driving is heavy and it takes a long time to charge the battery. In recent years, the development of electric vehicles has been accelerated again due to problems relating to severe pollution, exhaustion of fossil fuel, etc. The battery may be provided as a battery pack formed by integrally installing a plurality of battery cells.
[003] However, heat is generated in the battery cells when the battery pack is charged and discharged, and the performance of the battery is deteriorated when the generated heat is ignored, which may lead to shortening of the life of the battery cells. The battery pack provided with many battery cells may produce higher output voltages and charge and discharge with high currents. In particular, the battery system used as a power source unit for an automobile is discharged at high currents during vehicle acceleration and is charged with high currents under conditions such as regenerative braking. Because temperature rises for the battery system during charging and discharging with high currents, forced cooling is implemented via air or coolant. However, since thermal capacity of air is small, it is difficult for air to quickly cool the battery system in the state where its cells generate a significantly large amount of heat. Also, in this case, there is a disadvantage in that, if the amount of air flow is increased to increase the amount of battery heat reduction, the noise level of the cooling structure increases.
[004] Similarly, at very cold ambient conditions performance of battery cells is low compared to that of in the normal operating temperature range due to sluggish electro chemical reactions. In such conditions battery cells are to be heated.
[005] Currently, either of vertical or horizontal heat exchange plate is used at the bottom of the horizontal and vertical prismatic cells. The heat exchange plates are either cooled or heated as per the requirement by coolant which is a mixture of ethylene glycol and water that is fed to the heat exchange plates to cool or heat the prismatic cells. This structure can efficiently cool or heat the prismatic cells with the coolant. Due to packaging of both horizontal and vertical cells in the battery pack, the arrangement of using a single type of horizontal or vertical heat exchange plate is very complicated.
[006] Therefore, there exists a need for a battery pack thermal management system for an electric vehicle, using heat exchange plates which facilitates in cooling or heating of the battery pack of electric vehicles depending on the need and obviates the aforementioned drawbacks.

OBJECTS

[007] The principal object of the embodiments herein is to provide a battery pack thermal management system for an electric vehicle, having heat exchange plates which facilitates in cooling or heating of the battery pack for electric vehicles.
[008] Another object of embodiments herein is to provide a battery pack thermal management system for an electric vehicle in which a combination of horizontal heat exchange plates (at the bottom of vertical battery modules) and vertical heat exchange plates (at the bottom of horizontal battery modules)for thermal management(in both cases, heat exchange plates are touching the bottom part of battery cells).
[009] Yet another object of embodiments herein is to provide a battery pack thermal management system for an electric vehicle in which both sides of vertical heat exchange plates function as heat transfer medium for horizontal battery modules.
[0010] These and other objects of the embodiments herein will be better appreciated and understood when considered in conjunction with the following description and the accompanying drawings. It should be understood, however, that the following descriptions, while indicating embodiments and numerous specific details thereof, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the embodiments herein without departing from the spirit thereof, and the embodiments herein include all such modifications.
BRIEF DESCRIPTION OF DRAWINGS
[0011] The embodiments herein are illustrated in the accompanying drawings, throughout which like reference letters indicate corresponding parts in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0012] FIG. 1 depicts an enlarged view of a battery pack thermal management system for an electric vehicle, according to embodiments as disclosed herein;
[0013] FIG. 2 depicts a sectional view of a portion of the heat exchange plates which are used for battery pack thermal management system, according to embodiments as disclosed herein; and
[0014] FIG.3 depicts a perspective view of the perpendicular arrangement of heat exchange plates (combination of horizontal and vertical heat exchange plates in a battery pack) in the battery pack thermal management system, according to embodiments as disclosed herein.

DETAILED DESCRIPTION

[0015] The embodiments herein and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[0016] The embodiments herein achieve a battery pack thermal management system for an electric vehicle, having heat exchange plates which facilitates in cooling or heating of the battery pack for electric vehicles. Further, the embodiments herein achieve a battery pack thermal management system for an electric vehicle using combination of horizontal heat exchange plates (at the bottom of vertical battery modules) and vertical heat exchange plates (at the bottom of horizontal battery modules) for thermal management. Referring now to the drawings, and more particularly to Figs. 1 through 3, where similar reference characters denote corresponding features consistently throughout the figures, there are shown embodiments.
[0017] FIG. 1 depicts an enlarged view of a battery pack thermal management system for an electric vehicle, according to embodiments as disclosed herein. In an embodiment, the battery pack thermal management system (100) includes a battery pack (102), a plurality of battery cells(104), at least one heat exchange plate (106), the heat exchange plate (106)defining a fluid flow region at least one layer of interface material (110) and a coolant supply line (not shown) connected to the heat exchange plate (106).
[0018] The battery pack thermal management system (100) includes the battery pack (102). The battery pack (102) forms an enclosure for the stacking the plurality of cells (104). The battery pack (102) is configured to receive the plurality of cells (104) in a predetermined manner. In an embodiment, the plurality of cells (104) may be disposed in the battery pack (102) at least in one of horizontal position, vertical position or a combination of horizontal and vertical position. The plurality of the cells (104) generates heat which requires to be dissipated efficiently.
[0019] FIG. 2 depicts a sectional view of a portion of the battery pack thermal management system, according to embodiments as disclosed herein. The battery pack thermal management system (100) includes the at least one heat exchange plate (106).The heat exchange plate (106) is a flat plate which is disposed under the plurality of vertical cells and adjacent to horizontal cells. In an embodiment, the heat exchange plate (106) is made up of aluminum. However, it is also within the scope of the invention to provide any type of heat conductive material without otherwise deterring the intended function of the heat transfer as can be deduced from this description and corresponding drawings. Further, the heat exchange plate (106) includes a fluid flow region in U-shape for coolant flow or circulation. However, it is also within the scope of the invention to have a flow region in any possible shapes for the flow of coolant without otherwise deterring the intended function of the heat exchange as can be deduced from this description and corresponding drawings. The heat exchange plate (106) comprises an inlet (112) and an outlet (114). In an embodiment, the inlet (112) and the outlet (114) are provided on same side of the heat exchange plate (106). However, it is also within the scope of the invention to provide the inlet and the outlet in any type of construction without otherwise deterring the intended function of the heat exchange as can be deduced from this description and corresponding drawings. In an embodiment, the heat exchange plate (106), is made up of two aluminum sheets which are brazed together to form a coolant flow region. However, it is also within the scope of the invention to provide any type of manufacturing method to form the heat exchange plate without otherwise deterring the intended function of the heat exchange as can be deduced from this description and corresponding drawings.
[0020] FIG.3 depicts a perspective view of the perpendicular arrangement of heat exchange plates (combination of horizontal and vertical heat exchange plates in a battery pack) in the battery pack thermal management system, according to embodiments as disclosed herein. The battery pack thermal management system (100) includes at least one horizontal heat exchange plate (106a) which is disposed in thermal contact with a bottom surface of the plurality of cells (104) which are disposed vertically within the battery pack (102). At least one horizontal heat exchange plate (106a) defines a first fluid flow region for the coolant flow. Further, the battery pack thermal management system (100) includes at least one vertical heat exchange plate (106b) which is disposed in thermal contact with bottom of the plurality of cells (104) which are disposed horizontally within the battery pack (102). Both left wall and right wall of vertical heat exchange plate (106b) contacts the plurality of cells (104) which are disposed horizontally in the battery pack (102). The vertical heat exchange plate (106b) defines a second fluid flow region for the coolant flow. The horizontal heat exchange plates (106a) and the vertical heat exchange plates (106b) are disposed perpendicular to each other separated by a predetermined distance. In an embodiment, the heat exchange plates may be disposed in angular or any other predetermined shape with respect to horizontal battery modules and the vertical battery modules.
[0021] The horizontal heat exchange plates (106a) and the vertical heat exchange plates (106b) include a top surface and a bottom surface. The horizontal heat exchange plates (106a) and the vertical heat exchange plates includes at least one of plurality of dimples, depressions, indentations, and fins formed on at least one surface of heat exchange plates to enhance heat transfer between cells and coolant and to increase the structural strength of the heat exchange plate.
[0022] The battery pack thermal management system (100) includes the at least one layer of thermal interface material (TIM) (110). At least one layer of thermal interface material (110) is interposed between the heat exchange plate (106) and the plurality of cells (104). The thermal interface material (TIM) is used between heat exchange plate (106) and the plurality of cells (104) to maintain perfect contact and avoid air gaps in between heat exchange plate (106) and plurality of cells (104). In an embodiment, the thermal interface material layer (110) is made up of a material selected from the group consisting of acrylic sheet, silicon sheet and the like.
[0023] The battery pack thermal management system (100) further includes compression foams which are disposed under the horizontal heat exchange plates (106) to ensure perfect contact with the plurality of cells (104) and to avoid any change of shape in heat exchange plates (106) due to loads acting on them, during vehicle running conditions.
[0024] The battery pack thermal management system (100) further includes a coolant supply line (not shown) connected to the heat exchange plates (106). In an embodiment, the coolant is configured to flow in at least one U shaped path. In an alternate embodiment, the coolant may be configured to flow in at least one straight path or a zigzag path. The coolant supplied to the heat exchange plate (106) is a mixture of ethylene glycol and water. In an embodiment, the heat exchange plates (106) are configured to exchange heat with the coolant supplied through the coolant supply line to cool the battery pack (102). In an alternate embodiment, the heat exchange plate (106) is configured to exchange heat with the coolant supplied through the coolant supply line to heat the battery pack (102) i.e. the battery pack thermal management system (100) is configured either to cool or heat the battery pack (102) of the electric vehicle.
[0025] The technical advantages disclosed by the embodiments herein are, simultaneous usage of horizontal heat exchange plates for vertical battery modules and vertical heat exchange plates for horizontal battery modules for thermal management, both sides of vertical heat exchange plates functions as heat transfer medium for horizontal battery modules. Also, modularity and scalability is possible with minor change for different EV thermal applications, higher heat transfer area/weight ratio due to vertical heat exchange plates, and both heating and cooling of battery pack is possible with this arrangement.
[0026] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.