Spacer of an electric vehicle battery pack

Abstract

Spacers (68), comprising: a base (76) with an inlet side and an outlet side, wherein the inlet side is perpendicular to the outlet side; at least one rib (72, 72a, 72a', 72b, 72b') extending laterally from the base (76), wherein the at least one rib (72, 72a, 72a', 72b, 72b') is configured to direct a flow of coolant through a battery set (24) such that the flow received from an inlet air chamber (56) adjacent to the inlet side flows to an outlet air chamber (60) adjacent to the outlet side, wherein the inlet air chamber (56) spans the inlet side from the outlet side to an opposite side which is opposite the outlet side; and blocks (82) extending from the base (76), wherein the blocks (82) are designed to swirl the flow of the coolant, and wherein the blocks (82) define slots (86) to allow a certain flow of the coolant through the blocks (82).

Description

[0001] This disclosure relates generally to a cooled electric vehicle battery and in particular to the reversal of a coolant flow through the battery pack using a spacer.

[0002] Electric vehicles differ generally from conventional motor vehicles because they are selectively powered by one or more battery-powered electric motors. Conventional motor vehicles, on the other hand, rely exclusively on an internal combustion engine for propulsion. Electric vehicles can use electric motors instead of, or in addition to, the internal combustion engine.

[0003] Examples of electric vehicles include hybrid electric vehicles (HEVs), part-time hybrid electric vehicles (PHEVs), fuel cell vehicles, and battery electric vehicles (BEVs). An electric vehicle's powertrain typically includes a battery that stores electrical energy to power the electric motor. The battery can be charged before use. It can also be recharged while driving through regenerative braking or by a combustion engine.

[0004] Referring to Fig. 1, a prior art battery pack 2 comprises arrangements of battery cells 4. The prior art battery pack 2 is cooled with a coolant such as air. The air typically enters the battery pack 2 through an inlet air chamber 6 on one side of the battery cells 4. The air then flows between the battery cells 4 in a single direction D and moves into an outlet air chamber 8. The inlet air chamber 6 and the outlet air chamber 8 are located on opposite lateral sides of the battery cells 4. Assembling the prior art battery pack 2 is often difficult.

[0005] KR 10 2006 0 037 605 A, US 2006 / 0 214 641 A1, US 6 290 266 B1 and US 2007 / 0 026 300 A1 disclose generic devices.

[0006] The objective technical problem to be solved can be seen as eliminating or at least reducing the disadvantages of the prior art. This problem is solved by the subject matter of the independent patent claims.

[0007] A spacer according to an exemplary aspect of the present disclosure comprises, among other things, a base and at least one rib extending laterally from the rib. The rib is configured to direct a flow of coolant through a battery pack.

[0008] In another example of the foregoing spacer, the at least one rib includes at least a first rib extending laterally from the base in a first direction, and at least a second rib extending laterally from the base in a second direction opposite to the first direction.

[0009] In another example, one of the aforementioned spacers has at least one rib that receives the flow from an inlet side of the battery pack and reverses the flow to exit the battery pack at an outlet side. The inlet side is perpendicular to the outlet side.

[0010] In another example, one of the aforementioned spacers has its inlet side perpendicular to its outlet side.

[0011] In another example of one of the aforementioned spacers, at least one rib extends from the inlet side to the outlet side.

[0012] In another example, one of the aforementioned spacers has its inlet side on a vertical base of the battery pack.

[0013] In another example, one of the aforementioned spacers has its rib positioned between a battery cell and the base within a battery pack.

[0014] In another example, one of the protruding spacers directly touches the battery cell.

[0015] In another example, one of the aforementioned spacers provides the base and the battery cell opposite sides of a channel for communicating the flow through the battery pack, and the at least one rib provides another side of the channel.

[0016] In another example, one of the aforementioned spacers is the coolant air.

[0017] In another example, one of the aforementioned spacers contains blocks extending from its base. These blocks create turbulence in the coolant flow.

[0018] In another example, one of the aforementioned spacers defines slots in the blocks to allow some flow of coolant through the blocks.

[0019] A method for cooling a battery pack according to another exemplary aspect of the present disclosure includes receiving a flow of coolant through a vertical base of a battery pack. The flow is received between adjacent battery cells of the battery pack. The method includes redirecting the flow to exit through one side of the battery pack.

[0020] In another example of the foregoing procedure, the method involves reversing the flow using at least one rib extending laterally from a spacer.

[0021] In another example of one of the above methods, the method involves pressing the at least one rib against at least one of the battery cells.

[0022] In another example of one of the foregoing methods, the procedure involves moving the flow through the battery pack within channels provided on one side by a battery cell, on one opposite side by a base, and on another side by the at least one rib.

[0023] In another example of one of the above methods, the procedure involves swirling the flow moving through the channels using a block extending from the at least one rib.

[0024] In another example, one of the above procedures involves communicating some of the flow through a slot in the block.

[0025] The various features and advantages of the disclosed examples will become apparent to experts in the field from the detailed description. The figures accompanying the detailed description can be briefly described as follows: Fig. Figure 1 shows an exemplary battery set according to the state of the art. Fig. Figure 2 shows a schematic view of a powertrain of an electric vehicle which includes a battery pack of the present disclosure. Fig. Figure 3 shows a perspective view of the battery pack of Fig. 2. Fig. Figure 4 shows a cross-sectional view at line 4-4 in Fig. 3, which represents an exemplary spacer used to reverse a flow of coolant. Fig. Figure 5 shows a side view of the spacer from one direction of an outlet air chamber. Fig. Figure 6 shows a cross-sectional view at line 4-4 in Fig. 3, which represents another exemplary spacer. Fig. Figure 7 shows an enlarged view of area 7 in Fig. 6.

[0026] Fig. Figure 2 schematically shows a powertrain 10 for an electric vehicle. Although depicted as a hybrid electric vehicle (HEV), it is understood that the concepts described herein are not limited to HEVs and could be extended to other electrified vehicles, including but not limited to switchable hybrid electric vehicles (PHEVs) and battery electric vehicles (BEVs).

[0027] In one embodiment, the powertrain 10 is a powertrain system with drive force distribution, employing a first drive system and a second drive system. The first drive system comprises a combination of a motor 14 and a generator 18 (i.e., a first electric machine). The second drive system comprises at least one electric motor 22 (i.e., a second electric machine), the generator 18, and a battery pack 24. In this example, the second drive system is considered an electric drive system of the powertrain 10. The first and second drive systems generate torque to drive one or more sets of vehicle drive wheels 28 of the electric vehicle.

[0028] The motor 14, which in this example is an internal combustion engine, and the generator 18 can be connected by a power transmission unit 30, such as a planetary gear set. Of course, other types of power transmission units, including other gear sets and transmissions, can be used to connect the motor 14 and the generator 18. In a non-limiting embodiment, the power transmission unit 30 is a planetary gear set comprising a ring gear 32, a sun gear 34, and a carrier assembly 36.

[0029] The generator 18 can be driven by the motor 14 via the power transmission unit 30 to convert kinetic energy into electrical energy. Alternatively, the generator 18 can function as an electric motor to convert electrical energy into kinetic energy, thereby delivering torque to a shaft 38 connected to the power transmission unit 30. Since the generator 18 is functionally connected to the motor 14, the speed of the motor 14 can be controlled by the generator 18.

[0030] The ring gear 32 of the power transmission unit 30 can be connected to a shaft 40, which is connected to the vehicle drive wheels 28 via a second power transmission unit 44. The second power transmission unit 44 can contain a gear set with a variety of gears 46. Other power transmission units may also be suitable. The gears 46 transmit torque from the motor 14 to a differential 48 to ultimately provide traction to the vehicle drive wheels 28. The differential 48 can contain a variety of gears that enable the transmission of torque to the vehicle drive wheels 28. In this example, the second power transmission unit 44 is mechanically coupled to an axle 50 via the differential 48 to distribute torque to the vehicle drive wheels 28.

[0031] The electric motor 22 (i.e., the second electric machine) can also be used to drive the vehicle's drive wheels 28 by outputting torque to a shaft 52, which is also connected to the second power transmission unit 44. In one embodiment, the electric motor 22 and the generator 18 cooperate as part of a regenerative braking system, in which both the electric motor 22 and the generator 18 can be used as motors to deliver torque. For example, the electric motor 22 and the generator 18 can each output electrical power to the battery pack 24.

[0032] The battery pack 24 is an exemplary type of electric vehicle battery assembly. The battery pack 24 can be in the form of a high-voltage battery capable of outputting electrical power to operate the electric motor 22 and the generator 18. Other types of energy storage and / or output devices can also be used with the electric vehicle, which has the powertrain 10.

[0033] Now referring to the Fig. 3 to 5, the exemplary battery set 24 is cooled with a fluid coolant such as air. The battery set 24 includes an inlet air chamber 56, an outlet air chamber 60, a plurality of battery cells 64, and a plurality of spacers 68. The exemplary spacers 68 are positioned between one or more of the battery cells 64 to provide an arrangement of battery cells 64.

[0034] To cool the exemplary battery pack 24, air enters the inlet air chamber 56, flows between the battery cells 64 and into the outlet air chamber 60. The air carries away the heat energy generated by the battery cells 64 from the battery pack 24.

[0035] In this example, the inlet air chamber 56 is arranged on a vertical base of the battery cells 64 and spacers 68. "Vertical" refers to the horizon or ground and the typical orientation of the battery cells 64 during normal operation.

[0036] The exhaust air chamber 60, in contrast to the inlet air chamber 56, is located on a lateral side of the battery assembly 24. Such a placement of the inlet air chamber 56 makes it easier to reduce the lateral width of the battery assembly 24, which may be desirable in some assembly situations.

[0037] The air moving between the battery cells 64 is guided in channels 70. The spacers 68 and the battery cells 64 provide the channels 70. The spacers 68, as shown in the example, redirect the airflow, thus providing flexible positioning of the inlet air chamber 56 and the outlet air chamber 60.

[0038] To redirect the airflow, the exemplary spacers 68 incorporate a plurality of ribs 72 extending outwards from opposite sides of a planar base 76. At least some of the ribs 72 extend along a curved path, causing air flowing from the inlet air chamber 56 to redirect into the outlet air chamber 60.

[0039] In this example, the planar base 76 provides one side of the channel 70, the battery cells 64 provide an opposite side, and the ribs 72 provide another side. The channel 70 can contain three sides or any other number of sides.

[0040] The ribs 72, like the ribs 72a, can extend from the inlet air chamber 56 to the outlet air chamber 60; other ribs, like the rib 72b, can extend partially towards the outlet air chamber 60, but then end before reaching the outlet air chamber 60.

[0041] In other examples, the ribs 72 can begin at a position spaced apart from the inlet air chamber 56 and extend all the way to the outlet air chamber 60.

[0042] In the battery assembly 24, the ribs 72 touch the battery cell 64. The contact distances the planar section 76 of the spacer 68 from the battery cell 64.

[0043] Now referring to Fig. 6. In another example, blocks 82 can extend from ribs 72a'. The blocks 82 swirl the flow moving through the channels. Depending on the desired flow paths for the air supplied from inlet 56, some ribs 72b' can be positioned elsewhere within spacer 68'.

[0044] In some examples, cavities V are present behind the blocks 82. The blocks 82 may accordingly contain slots 86 that supply air through the blocks 82 to the cavity areas V.

[0045] The foregoing description is exemplary and not limiting. Variations and modifications of the disclosed examples, which do not necessarily deviate from the essence of this disclosure, may be obvious to those skilled in the field. Consequently, the scope of legal protection available for this disclosure can only be determined by reading the following patent claims.

Claims

[1] Spacers (68), comprising: a base (76) with an inlet side and an outlet side, wherein the inlet side is perpendicular to the outlet side; at least one rib (72, 72a, 72a', 72b, 72b') extending laterally from the base (76), wherein the at least one rib (72, 72a, 72a', 72b, 72b') is configured to direct a flow of coolant through a battery set (24) such that the flow received from an inlet air chamber (56) adjacent to the inlet side flows to an outlet air chamber (60) adjacent to the outlet side, wherein the inlet air chamber (56) spans the inlet side from the outlet side to an opposite side which is opposite the outlet side; and blocks (82) extending from the base (76), wherein the blocks (82) are designed to swirl the flow of the coolant, and wherein the blocks (82) define slots (86) to allow a certain flow of the coolant through the blocks (82). [2] Spacer (68) according to claim 1, wherein the at least one rib (72, 72a, 72a', 72b, 72b') comprises at least one first rib (72, 72a, 72a', 72b, 72b') extending outwards from the base (76) in a first direction, and at least one second rib (72, 72a, 72a', 72b, 72b') extending outwards from the base (76) in a second direction opposite to the first direction. [3] Spacer (68) according to claim 1, wherein the inlet side is perpendicular to the outlet side. [4] Spacer (68) according to claim 1, wherein the at least one rib (72, 72a, 72a', 72b, 72b') extends from the inlet side to the outlet side. [5] Spacer (68) according to claim 1, wherein the inlet side is located on a vertical base of the battery pack (24). [6] Spacer (68) according to claim 1, wherein the at least one rib (72, 72a, 72a', 72b, 72b') is positioned between a battery cell (64) and the base (76) within a battery pack (24). [7] Spacer (68) according to claim 6, wherein the base (76) and the battery cell (64) provide opposite sides of a channel (70) for communicating the flow through the battery pack (24) and the at least one rib (72, 72a, 72a', 72b, 72b') provides another side of the channel (70). [8] Method for cooling a battery pack (24), comprising: Receiving a flow of coolant from an inlet air chamber (56) on a vertical base of a battery pack (24), wherein the flow is received between adjacent battery cells (64) of the battery pack (24); and Reversing the flow to exit through a first side of the battery assembly (24) into an outlet air chamber (60), the inlet air chamber (56) spanning the vertical floor from the first side to an opposite second side. [9] Method according to claim 8, further comprising reversing the flow using at least one rib (72, 72a, 72a', 72b, 72b') extending laterally from a base (76) of a spacer (68). [10] Method according to claim 9, further comprising pressing the at least one rib (72, 72a, 72a', 72b, 72b') against at least one of the battery cells (64). [11] Method according to claim 9, wherein the flow moves through the battery pack (24) within channels (70) provided on one side by a battery cell (64), on an opposite side by a base (76) and on another side by the at least one rib (72, 72a, 72a', 72b, 72b'). [12] Method according to claim 11, further comprising swirling the flow moving through the channels (70) using a block (82) extending from the at least one rib (72, 72a, 72a', 72b, 72b'). [13] Method according to claim 12, further comprising communicating some of the flow through a slot (86) in the block (82). [14] Method according to claim 8, further comprising turning some of the flow using at least one first rib (72, 72a, 72a', 72b, 72b') on a first side of the base (76) of the spacer (68) and turning some of the flow using at least one second rib (72, 72a, 72a', 72b, 72b') on an opposite second side of the base (76). [15] Spacers (68), comprising: a base (76) with an inlet side and an outlet side, wherein the inlet side is perpendicular to the outlet side; at least one rib (72, 72a, 72a', 72b, 72b') extending laterally from the base (76), wherein the at least one rib (72, 72a, 72a', 72b, 72b') is configured to direct a flow of coolant through a battery set (24) such that the flow received from an inlet air chamber (56) adjacent to the inlet side flows to an outlet air chamber (60) adjacent to the outlet side, wherein the inlet air chamber (56) spans the inlet side from the outlet side to an opposite side facing the outlet side; and at least one block (82) configured to swirl the coolant flow, the at least one block (82) extending from the at least one rib (72, 72a, 72a', 72b, 72b') transversely to a principal flow direction through the channel (70) from the inlet air chamber (56) to the outlet air chamber (60), the at least one rib (72, 72a, 72a', 72b, 72b') being positioned between a battery cell (64) and the base (76) within the battery pack (24), the base (76) and the battery cell (64) providing opposite sides of a channel (70) for guiding the flow through the battery pack (24), and the at least one rib (72, 72a, 72a', 72b, 72b') forming another side of the channel (70) provides.

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