Battery pack flow control method

Abstract

Method (200) for controlling a flow by means of a battery set (14) comprising the following: in a first operating state, moving a flow through a first section (64a - 64e) of an enclosure (60) using a first fan (68a - 68e), and moving a flow through a second section (64a - 64e) of the enclosure (60) using a second fan (68a - 68e); in a second operating state, moving a flow through the second section (64a - 64e) using the first fan (68a - 68e); and Targeted supply of energy to a powertrain (10) of an electrified vehicle using a first group (18a - 18e) of battery cells within the first section (64a - 64e) and a second group (18a - 18e) of battery cells within the second section (64a - 64e); wherein the fans (68a - 68e) each include a reverse current blocking device (92), wherein in the first operating state the reverse current blocking device (92) is in a first position to allow the flow to leave the housing (60) through the fan (68a - 68e), and in the second operating state the reverse current blocking device (92) is in a second position to prevent the flow from entering the open area (80) through the fan (68a - 68e).

Description

TECHNICAL AREA

[0001] This disclosure relates generally to a method for controlling the flow through a battery set and, in particular, to a method that uses an array of individual fans to control the flow through sections of a battery set. BACKGROUND

[0002] In general, electrified vehicles differ from conventional motor vehicles in that they are specifically powered by one or more electric motors, which are supplied with energy by battery cells in a battery pack. These electric motors can power the electrified vehicles instead of, or in addition to, an internal combustion engine. Examples of electrified vehicles include hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), fuel cell vehicles (FCVs), and battery electric vehicles (BEVs).

[0003] Referring to Fig. Figure 1 contains an exemplary state-of-the-art battery pack 2 with battery cells that supply energy to the electric motors of an electrified vehicle. A single fan 4 is connected to a duct 6. The fan 4 draws an airflow from the battery pack 2 through the duct 6. This airflow can cool the battery pack 2.

[0004] DE 603 ​​14 788 T2 discloses a battery power supply device for supplying a high drive current required for large hybrid vehicles, a method for controlling the power supply device and a method for assigning an address.

[0005] US Patent 5,414,591 A describes a magnetic disk storage system in which magnetic disk drives are effectively cooled. Even if a fan for one of the magnetic disk drives malfunctions or fails, the temperature rise of that drive can be minimized. For this purpose, the magnetic disk storage system provides blowing devices for each disk drive, and the disk drives are separated by partitions with openings to allow cooling air to circulate between adjacent disk drives. SUMMARY

[0006] According to the invention, methods with the features of claim 1, claim 5 and claim 11 are proposed. Advantageous embodiments of the invention are specified in the dependent claims and the following description.

[0007] A method for controlling a flow through a battery pack according to an exemplary aspect of the present disclosure includes, among other things, in a first operating state, moving a flow through a first section of an enclosure using a first fan, and moving a flow through a second section of the enclosure using a second fan. In a second operating state, the method further includes moving the flow through the second section using the first fan. The fans each include a backflow preventer, wherein in the first operating state the backflow preventer is in a first position to allow the flow to exit the enclosure through the fan, and in the second operating state the backflow preventer is in a second position to prevent the flow from entering the open section through the fan.

[0008] In a further non-restrictive embodiment of the aforementioned method, the method includes a change from the first operating state to the second operating state in response to a change in temperature.

[0009] In a further non-restrictive embodiment of any of the aforementioned methods, the change in temperature involves a deviation of an actual temperature of the second section from an expected temperature of the second section.

[0010] In a further non-restrictive embodiment of any of the aforementioned methods, the change in temperature involves a deviation of an actual temperature of the second section from an average temperature of the battery pack.

[0011] In a further non-restrictive embodiment of any of the aforementioned methods, the change in temperature involves a change in the temperature of a group of battery cells within the second section.

[0012] In a further non-restrictive embodiment of any of the aforementioned methods, the method includes, in the second operating state, adjusting the first fan to increase the flow moved by the first fan.

[0013] In a further non-restrictive embodiment of any of the aforementioned methods, the adjustment is carried out in response to a difference between a temperature of battery cells in the second section and a temperature of battery cells in another area of ​​the housing.

[0014] In another non-restrictive embodiment of any of the aforementioned methods, the adjustment is based on a flow model.

[0015] In a further non-restrictive embodiment of any of the aforementioned methods, the method, in the second operating state, involves moving the flow through the second section and a third section using a third fan, wherein the second section is positioned between the first section and the third section within the enclosure.

[0016] In a further non-restrictive embodiment of any of the aforementioned methods, the method involves the targeted supply of energy to a powertrain of an electrified vehicle using a first group of battery cells within the first section and a second group of battery cells within the second section.

[0017] In a further non-restrictive embodiment of any of the aforementioned methods, the first fan rotates about a first axis to move the flow, and the second fan rotates about a second axis to move the flow. The first axis is aligned in one direction so that the flow is transferred through the first section. The second axis is aligned in one direction so that the flow is transferred through the second section.

[0018] A method for controlling a flow through a battery pack according to an exemplary aspect of the present disclosure includes, among other things, transferring a flow through a first section of an enclosure using a first fan, and transferring a flow through a second section of the enclosure using a second fan. The method further includes increasing the rotational speed of the first fan to transfer the flow through the second section using the first fan in response to a temperature change in the second section. The fans each include a backflow preventer, wherein, in the first operating state, the backflow preventer is in a first position to allow the flow to exit the enclosure through the fan, and in the second operating state, the backflow preventer is in a second position to prevent the flow from entering the open region through the fan.

[0019] In a further non-restrictive embodiment of the aforementioned method, the temperature change in the second section involves a deviation of an actual temperature of the second section from an expected temperature of the second section.

[0020] In a further non-restrictive embodiment of any of the aforementioned methods, the temperature change in the second section involves an increase in the temperature of a group of battery cells in the second section.

[0021] In a further non-restrictive embodiment of any of the aforementioned methods, the temperature change in the second section involves a deviation of an actual temperature of the second section from an average temperature of the battery pack.

[0022] In a further non-restrictive embodiment of any of the aforementioned methods, the first fan rotates about a first axis to move the flow, and the second fan rotates about a second axis to move the flow. The first axis is aligned in one direction so that the flow is transferred through the first section. The second axis is aligned in one direction so that the flow is transferred through the second section.

[0023] In a further non-restrictive embodiment of any of the aforementioned methods, the increase is based on a flow model.

[0024] In a further non-restrictive embodiment of one of the aforementioned methods, the increase also occurs in response to the fact that the second fan transmits an insufficient flow through the second section.

[0025] In a further non-restrictive embodiment of any of the aforementioned methods, the method involves transferring a flow through the second section and a third section using a third fan, wherein the second section is positioned between the first section and the third section within the enclosure. BRIEF DESCRIPTION OF THE FIGURES

[0026] The various features and advantages of the disclosed examples will become apparent to the person skilled in the art from the following detailed description. The figures accompanying the detailed description can be briefly described as follows: Fig. Figure 1 shows an exemplary battery set representing the state of the art. Fig. Figure 2 shows a powertrain of an exemplary electrified vehicle. Fig. Figure 3 shows a partial sectional view of a battery pack current control system used to control flow through a component in the drivetrain of Fig. 2 battery packs are used. Fig. Figure 4 shows a partially schematic cross-sectional view of selected parts from Fig. 3, when the battery pack flow control system is in its first operating state. Fig. 5 shows the cross-section of Fig. 4, when the battery pack flow control system is in a second operating state. Fig. Figure 6 shows a partially schematic cross-sectional view of another exemplary embodiment of a battery pack and a battery pack flow control system in a first operating state. Fig. Figure 7 shows the cross-section of Fig. 6 in a second operating state. Fig. Figure 8 shows steps of an exemplary procedure for controlling a flow through the battery pack of the Fig. 2 or Fig. 6 or another set of batteries. Fig. Figure 9 shows the steps of an exemplary procedure for controlling a flow through the battery pack from the Fig. 2 or Fig. 6 or another set of batteries. DETAILED DESCRIPTION

[0027] This disclosure relates generally to a method for controlling a flow through a battery pack and, in particular, a method that controls an array of individual fans within a fan array to influence the flow through different sections of the battery pack. The flow is a fluid, such as air, which can cool the battery pack. In another example, the flow can heat the battery pack.

[0028] Referring to Fig. 2, a powertrain 10 of a hybrid electric vehicle (HEV) includes a battery pack 14, which houses groups 18 of battery cells. In this example, each group 18 contains three individual battery cells.

[0029] The drive train 10 further comprises an internal combustion engine 20, a motor 22, and a generator 24. The motor 22 and the generator 24 are types of electric machines. The motor 22 and the generator 24 can be separate or have the form of a combined motor-generator.

[0030] In this embodiment, the powertrain 10 is a power-split powertrain employing a first drive system and a second drive system. The first and second drive systems generate torque to drive one or more sets of vehicle drive wheels 28. The first drive system comprises a combination of the power unit 20 and the generator 24. The second drive system comprises at least the motor 22, the generator 24, and the battery 14. The motor 22 and the generator 24 are components of an electric drive system of the powertrain 10.

[0031] The power engine 20 and the generator 24 can be connected by a power transmission unit 30, for example, a planetary gear set. Of course, other types of power transmission units, including other gear sets and transmissions, can also be used to connect the power engine 20 to the generator 24. 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.

[0032] The generator 24 can be driven by the power machine 20 via the power transmission unit 30 to convert kinetic energy into electrical energy. Alternatively, the generator 24 can also function as a motor to convert electrical energy into kinetic energy and thereby deliver torque to a shaft 38 connected to the power transmission unit 30.

[0033] The ring gear 32 of the power transmission unit 30 is connected to a shaft 40, which is connected via a second power transmission unit 44 to the vehicle drive wheels 28. The second power transmission unit 44 can comprise a wheelset with multiple wheels 46. Other power transmission units could be used in other examples.

[0034] The wheels 46 transmit torque from the power unit 20 to a differential 48 to ultimately provide traction for the vehicle's drive wheels 28. The differential 48 can include multiple wheels, enabling the transmission of torque to the vehicle's 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 the torque to the vehicle's drive wheels 28.

[0035] The motor 22 can be used to drive the vehicle's drive wheels 28 by transmitting torque to a shaft 54, which is also connected to the second power transmission unit 44. In this embodiment, the motor 22 and the generator 24 cooperate as part of a recuperation braking system, in which both the motor 22 and the generator 24 can be used as motors to deliver torque. For example, both the motor 22 and the generator 24 can each deliver electrical power to charge the cells of the battery 14.

[0036] Now on Fig. 3. Referring to further reference to Fig. Figure 2 shows an exemplary flow control system 58 for the battery pack 14 connected to a housing 60 of the battery pack 14. The housing 60 is divided into sections 64a-64e or regions, which are represented by dashed lines.

[0037] Sections 64a-64e each contain one of the groups 18a-18e of battery cells. In this example, each section 64a-64e contains three individual battery cells.

[0038] In another example, one or more of sections 64a-64e may contain a battery support device, such as a Battery Electronic Control Module (BECM), instead of, or in addition to, one of the groups 18a-18e of battery cells.

[0039] Sections 64a-64e are of similar size. In another example, sections 64a-64e could be of different sizes to accommodate the battery support device, a different number of battery cells than three, or other components.

[0040] The example battery cells are prismatic cells with terminals pointing upwards within the battery pack 14. In another example, the battery cells are cylindrical. Other types of battery cells could be used.

[0041] The exemplary enclosure 60 contains five sections 64a-64e, but could also contain a different number. In this example, no partitions are used, and sections 64a-64e are not structurally defined as separate from one another. In another example, sections 64a-64e could be partially separated from one another by a partition structure, such as a wall located within the enclosure 60. If a partition structure is used, the partition structure includes an engineering gap, such as an opening, that allows flow between sections 64a-64e if such flow is required.

[0042] System 58 includes a fan assembly. In this example, the fan assembly includes a fan array 66, which has several fans 68a-68e. The exemplary fans 68a-68e are mounted directly on a side wall 72 of the enclosure 60. The exemplary fan array 66 contains five fans 68a-68e, but could also contain a different number of fans.

[0043] The fan array 66 moves the flow through the battery pack 14. In this example, the flow within the housing 60 can move through spaces between the individual battery cells in groups 18a-18e. The flow can also move through spaces between groups 18a-18e and between the top of the groups and a top surface 74 of the housing 60.

[0044] Each of the five sections 64a-64e is connected to one of the five fans 68a-68e. In another example, more than one of the sections 64a-64e is connected to one of the fans 68a-68e. That is, the number of fans 68a-68e does not have to match the number of sections 64a-64e.

[0045] The fans 68a-68e are designed to draw an airflow through at least one corresponding section 64a-64e. The airflow moves to the sections 64a-64e through an inlet provided by one or more openings (not shown) in a side wall 76 of the housing 60.

[0046] In another example, the fans 68a-68e are designed to push the flow through at least one corresponding section 64a-64e. In such an example, the openings could provide an outlet from the housing.

[0047] In yet another example, the fans 68a-68e are reversible and thus designed to push or pull the flow through sections 64a-64e in a targeted manner.

[0048] The exemplary fans 68a-68e each contain a bladed rotor that rotates about an axis A to move the flow. The axis A is shown in conjunction with fan 68a, but it is understood that each of the remaining fans 68b-68e has a corresponding axis of rotation. The exemplary fans 68a-68e are oriented such that the axis A is aligned in one direction, so that the flow is transferred through groups 18a-18e in a connected section of sections 64a-64e. Alternatively, the fans 68a-68e can each contain an impeller that moves air perpendicular to the axis A and approximately tangential to the rotation of the impeller about the axis A.

[0049] Groups 18a-18e terminate at laterally oriented sides 78. Fans 68a-68e are spaced from the lateral sides 78, creating an open area 80 between the fan array 66 and the groups 18a-18e of battery cells. Within this open area 80, flow can move between sections 64a-64e. If physical dividers are used to separate sections 64a-64e, the physical dividers would not completely block the flow between sections 64a-64e within the open area 80. The physical dividers could include openings to allow, for example, flow between sections 64a-64e within the open area 80. The open area 80 lies within the enclosure 60.

[0050] A sensor assembly 82a-82e is connected to each of the sections 64a-64e. The sensor assembly 82a-82e can be used to detect a temperature within a corresponding section 64a-64e. The exemplary sensor assemblies 82a-82e can detect a temperature of one or more associated battery cells, or the temperature of an element that is conductively coupled to the associated battery cells, such as a busbar.

[0051] The flow through sections 64a-64e can change the temperatures of the battery cells and other components in sections 64a-64e. For example, increasing the flow through section 64a can reduce the temperature of section 64a, and thus reduce the temperatures detected by sensor assembly 82a.

[0052] In general, a relatively uniform flow across groups 18a-18e of the battery cells can cool or heat the battery cells to a desired level. Under certain conditions, deviations from a nearly uniform flow may be desirable.

[0053] On the Fig. 4 and Fig. 5 Referring to, with further reference to Fig. 3. Each of the fans 68a-68e is operatively connected to a controller 84. The fans 68a-68e can be individually adjusted by the controller 84 to selectively increase or decrease the flow through one or more of the sections 64a-64e relative to other sections 64a-64e. The groups 18a-18e are in the Fig. 4 and Fig. 5 schematically represented.

[0054] In this example, the controller 84 adjusts the rotational speeds of the individual fans 68a-68e relative to each other to increase or decrease the flow through sections 64a-64e. The controller 84 can receive temperature readings from the sensor arrays 82a-82e and adjust the rotational speeds in response to changes in the temperature readings. For example, if more flow is desired in section 64b than in section 64a, the rotational speed of fan 68b can be increased relative to the rotational speed of fan 68a. The effective rotational speeds of the individual fans 68a-68e can be controlled by adjusting the analog power flowing to the fans 68a-68e, which is controlled by pulse-width modulation of the power or by other means.

[0055] Although rotational speeds are set in this example, in other examples the controller 84 can make other settings to vary the flow through one or more of the sections 64a-64e relative to other sections 64a-64e. For example, the controller 84 could actuate an array of vanes to increase or decrease the flow.

[0056] The operating state of system 58 can change to alter the flow through sections 64a-64e. For example, the operating state can change in response to an increase in the temperatures of the battery cells in one or more of sections 64a-64e of battery pack 14 relative to the other battery cells of battery pack 14. The sensor array 82a-82e connected to sections 64a-64e can detect temperatures and send temperature information to the controller 84, which then adjusts the fan array 66 to change the flow through sections 64a-64e.

[0057] A deviation in the temperatures of sections 64a-64e may be caused, at least in part, by an obstruction that prevents the flow from entering the housing 60. For example, the battery pack 14 is positioned behind a rear seat 88 of an electric vehicle. Seat belt anchorages 90a, 90b, and 90c for the rear seat 88 may block the flow to the openings 76 of the housing 60. In particular, seat belt anchorage 90b may prevent the flow from entering section 64b and section 64c.

[0058] The exemplary battery pack 14 extends transversely along the rear of the rear seat 88. The number and size of the battery cells within the battery pack 14 offer little or no space for a channel network on the lateral sides of the battery pack 14.

[0059] In this example, battery pack 14 is approximately 1000 millimeters wide. Each of the sections 64a-64e has a width of approximately 200 millimeters. The number of sections 64a-64e and their widths may vary from this example. The thickness of the example battery cells can be 12 to 25 millimeters for prismatic cells and 5 to 13 millimeters for pocket-shaped cells. If battery cells of such thickness are used, sections 18a-18e would likely each contain more than three individual battery cells.

[0060] Each of the example fans 68a-68e can move approximately 34 m 3 / h through the associated section 64a-64e. In some examples, the fans 64a-64e are the same size as the seat fans. The number and size of sections 64a and 64e can be a function of the maximum flow required for the battery pack 14 and the volumetric capacity of the fans 64a-64e.

[0061] Due to the obstructed flow, the temperatures of battery cells in group 18b and group 18c in section 64c can rise. To lower the temperature of the battery cells in sections 64b and 64c, the controller 84 can increase the speed of fans 68b and 68c relative to the remaining fans 68a, 68d, and 68e. Increasing the speed of fans 68b and 68c will increase the flow through sections 64b and 64c.

[0062] The operating state may change in response to other information instead of, or in addition to, temperatures within sections 64a-64e. For example, the failure of one of the fans 68a-68e could trigger a change in the operating state.

[0063] As an example, the System 58 from Fig. 4 according to a first operating state. In the first operating state, fan 68a draws a flow through section 64a, fan 68b draws the flow through section 64b, fan 68c draws the flow through section 64c, fan 68d draws the flow through section 64d, and fan 68e draws the flow through section 64e. In this example, the first operating state corresponds to the situation when each of the fans 68a-68e is fully functional and able to maintain a desired flow through a corresponding section 64a-64e.

[0064] In Fig. In step 5, system 58 changed to operate according to a second operating state. Fig. 5. The fan 68d is inoperative or unable to operate at a level sufficient to draw adequate airflow through section 64d. As a result, system 58 has transitioned to the second operating state.

[0065] In the exemplary second operating state, the controller 84 has increased the speed of fans 68c and 68e relative to the other fans 68a and 68b. Operating fans 68c and 68e can compensate for the inability of fan 68d to draw sufficient airflow through section 64d. The change in the speed of fans 68c and 68e represents the change from the first to the second operating state in this example.

[0066] When the exemplary system 58 operates in the second operating state, fan 68c draws the flow through section 64c and the adjacent section 64d. Additionally, fan 68e draws the flow through section 64e and the adjacent section 64d. Increasing the speed of fans 68c and 68e increases the flow moved by fans 68c and 68e, which helps fans 68c and 68e draw the flow from section 64d in addition to sections 64c and 64e. The open area 80 provides an engineering opening or gap between the adjacent sections 64a-64e, allowing the flow to move from one of the sections 64a-64e to another.

[0067] In some examples, the fans 68a-68e can each include a backflow preventer 92, which is shown schematically in conjunction with fan 68d. The backflow preventer 92 can allow flow in one direction through fan 68, but block backflow through fan 68d in a second, opposite direction.

[0068] When system 58 is in its first operating state, the backflow preventer 92 is in the first position of Fig. 4, to allow the flow to leave the housing 60 through the fan 68d. When the system 58 is in the second operating state, the backflow preventer 92 is in the second position of Fig. 5, to prevent the flow from the fan 68d entering the open area 80.

[0069] The direction of the flow can cause the backflow preventer 92 to move between the first position and the second position. For example, the backflow preventer 92 can include flaps that open when the flow moves from the open area 80 to the fan 68d, and close when the flow moves from outside the enclosure 60 to the fan 68d.

[0070] In some examples, the controller 84 actuates the reverse current lock 92 and holds it in the first or second position. This allows the reverse current lock 92 to be used to change the system 58 between the first and second operating states. The reverse current lock 92 can be used instead of, or in addition to, increasing the speed of fan 68c and fan 68e relative to the speed of fans 68a and 68b.

[0071] In examples where the sections are separated by physical dividers, each containing one or more openings to selectively allow flow between sections 64a-64e within the open area, the size of one or more openings can be adjustable. For example, the control could actuate 84 louvers or a similar structure to selectively increase or decrease the effective opening size. Increasing the size of the opening allows more flow from one of sections 64a-64e through the opening to an adjacent section. Decreasing the size of the opening allows less flow from one of sections 64a-64e through the opening to an adjacent section.

[0072] Now referring to the Fig. 6 and Fig. Figure 7 contains another exemplary system 158 for controlling the flow by means of a battery set 114, comprising six sections 164a-164f, each housing a corresponding group 118a-118f of battery cells. Each of the sections 164a-164f contains a corresponding group 118a-118f of battery cells. The groups 118a-118f are shown schematically.

[0073] The battery cells in groups 118a-118f terminate at a laterally oriented side, represented by line 178. Each of the sections 164a-164f is connected to a corresponding fan 168a-168f. An open area 180 is positioned between the laterally oriented side and the fans 168a-168f.

[0074] The battery pack 114 contains a grid assembly 94, which is positioned between the groups 118a-118f and the fans 168. The grid assembly 94 is operatively connected to a controller 184, which is also operatively connected to the fans 168a-168f.

[0075] The grid arrangement 94 contains several lamellae 96. The control 184 can selectively actuate individual lamellae 96 of the grid arrangement 94 to change the flow through sections 164a-164f of the battery pack 114. A person skilled in the art who makes use of this disclosure would understand how to actuate selected lamellae of the grid arrangement 94.

[0076] In Fig. 6. The lamellae 96 of the grid arrangement 94 are aligned with a direction of flow through the battery sets within sections 164a-164f. This positioning of the lamellae 96 facilitates the guidance of the flow between sections 164a-164f and the associated fans 168a-168f. In Fig. Figure 6 shows the positioning of the lamellae 96, representative of the exemplary system 158, which operates in a first operating state.

[0077] In Fig. 7 Some of the vanes 96 have been actuated to direct the flow so that it moves between section 164e and fans 168d and 168f instead of between section 164e and fan 168e. The vanes 96 can be moved to the position of Fig. 7 must be activated if the fan 168e is unable to move sufficient airflow through section 164e. The positioning of the louvers 96 of Fig. 7 is representative of the exemplary system 158, which operates in a second operating state.

[0078] Referring to Fig. 8, an exemplary method 200 controls the flow through a battery pack, which is battery pack 14 of the Fig. 3-5, the battery set 114 of the Fig. 6 and Fig. 7 or another battery pack. The steps of procedure 300 can be performed on processing circuits of a controller that is operatively connected to the temperature sensors, a fan array, and other parts of the battery pack.

[0079] In step 210, the method 200 operates in a first operating state. In step 210, the method 200 moves the flow through a first section of a battery pack enclosure using a first fan, and moves the flow through a second section of the battery pack enclosure using a second fan.

[0080] Procedure 200 advances to step 220 when operating according to a second operating state. In step 220, procedure 200 moves the flow through the second section using the first fan.

[0081] One or more factors can cause the procedure 200 to transition from the first operating state of step 210 to the second operating state of step 220.

[0082] In one example, a failure of the second fan can cause procedure 200 to proceed from step 210 to step 220.

[0083] In another example, the second fan is operational, but procedure 200 proceeds from step 210 to step 220 because the second fan is unable to move sufficient flow through the second section.

[0084] In further examples, procedure 200 transitions from step 210 to step 220 in response to a temperature change. For instance, a controller operatively connected to temperature sensors belonging to the second section can compare the actual temperature of the second section with an expected temperature of the second section. If the actual temperature differs from the expected temperature, procedure 200 transitions from step 210 to step 220. The deviation required to trigger the transition from step 210 to step 220 can be a deviation exceeding a threshold value, such as two degrees Celsius. The actual temperature reading can be an actual temperature reading of battery cells within the second section of the battery pack enclosure.

[0085] The expected temperature reading can be an expected temperature reading for battery cells within the second section. Alternatively, the expected temperature reading can be an average temperature of the battery pack, such as an average temperature of all battery cells within the battery pack housing.

[0086] In step 220, procedure 200 can adjust the first fan to direct the flow through the second section. An example of such an adjustment would be increasing the speed of the first fan to increase the flow it moves. Increasing the flow moved by the first fan will assist it in moving the flow through both the first and second sections.

[0087] In some examples, procedure 200 can adjust the first fan at step 220 based on a flow model. For example, a database stored in a memory section of the controller can provide the flow model.

[0088] The database can contain a table of flow rates associated with different fan speeds, as well as estimates of the flow required to reduce temperature differences. The flow required to reduce temperatures can be influenced by various factors, such as ambient temperature, humidity, etc. These factors can be stored in the table and affect the flow required to reduce temperatures by a desired amount.

[0089] If procedure 200 is at step 220 and the temperature of the second section is, for example, two degrees Celsius higher than a desired temperature, procedure 200 refers to the flow model to determine a new target speed for the first fan. When the first fan is running at the new target speed, it moves enough flow through the second section to reduce the temperature by two degrees Celsius.

[0090] Now referring to Fig. 9, another procedure 300 for controlling the flow by means of a battery set begins at step 310. The procedure 300 can be used in conjunction with the battery set 14 of the Fig. 3-5, the battery set 114 of the Fig. 6 and Fig. 7 or another battery pack. The steps of procedure 300 can be performed on processing circuits of a controller that is operatively connected to the temperature sensors, a fan array, and other parts of the battery pack.

[0091] After starting at step 310, procedure 300 advances to step 320. Step 320 essentially compares temperature data for different sections of the battery pack housing. This temperature data includes, for example, battery cell temperatures.

[0092] In some examples, step 320 calculates whether the temperature change rate in one section of the battery pack enclosure differs from the average temperature of the other sections of the battery pack enclosure. In another example, step 320 calculates whether the temperature change rate in one section of the battery pack differs from the average temperature of all sections of the battery pack enclosure.

[0093] The procedure then proceeds to step 330, which performs a calculation to determine whether a temperature change rate in a section of the battery pack enclosure differs from an expected temperature change rate for that section. An expected temperature change rate for a section of the battery pack enclosure could be based on several variables, including a thermal model of battery heat generation / dissipation, airflow provided by fans, the RMS value of the battery cell current, battery cell mass, temperatures, and so on. Regarding the RMS value of the battery cell current, squaring the current changes the negative current values ​​to positive ones. Thus, current both inside and outside the battery contributes to the RMS value of the current. Both charging and discharging can generate thermal energy.

[0094] Procedure 300 then advances to step 340, which references the calculations of steps 320 and 330. If, based on the calculations of steps 320 and 330, the temperature of a section of the battery pack enclosure does not deviate, procedure 300 returns to starting step 310. If, based on the calculations of steps 320 and 330, the temperature of a section of the battery pack enclosure deviates, the procedure advances to step 350. Advancement to step 350 from step 340 can be based on a deviation calculated in step 320, a deviation calculated in step 330, or both.

[0095] In step 350, procedure 300 calculates a flow increase required by one or more fans adjacent to the section of the battery pack where the temperature deviation occurs. The required flow increase can be calculated using a flow model that includes fan current. The flow increase corresponds to the increase needed to adjust the thermal energy in the section so that no further temperature deviation occurs there.

[0096] Procedure 300 then advances to step 360, where it calculates whether at least one area, such as the center, of a battery cell within the section with the differing temperature is predicted to exceed the desired temperatures due to thermal inertia. For example, the temperature sensor may measure the outside of the battery cell, but the critical temperature in the center of the battery may be warmer and may take longer to respond to changes in airflow.

[0097] The forecast in step 360 can be based on a thermal model of battery cell temperatures, which incorporates the temperature rise rate, temperatures, battery heat generation / dissipation, and thermal properties of the battery. Exemplary thermal properties might include battery mass, density, size, shape, thermal conductivity, interconnectivity, emissivity, and other factors well-known in the field of thermal analysis. The forecast can be specific to a particular area of ​​a battery cell within the section, such as the central region of the cell.

[0098] If step 360 does not predict that the battery cell will exceed desired temperatures due to thermal inertia, the procedure 300 advances to step 370, in which a duty cycle of one or more adjacent fans is increased to provide the flow increase calculated in step 340 to the section where the temperature deviation occurs.

[0099] If, at step 360, it is predicted that the battery cell will exceed desired temperatures due to thermal inertia, the procedure 300 advances to step 380, in which an additional flow increase is added to the flow increase calculated in step 340, as requested by the adjacent fan or fans.

[0100] Procedure 300 then proceeds from step 380 to step 370, where the duty cycle of one or more adjacent fans is increased to provide the flow increase calculated in step 340 and the additional flow increase calculated in step 380.

[0101] When moving back from step 380 to step 370, the flow in step 370 includes the flow increase calculated in step 340 and the additional flow increase calculated in step 380. When moving forward from step 360 to step 370, the flow in step 370 includes the flow increase calculated in step 340.

[0102] Procedure 300 ends at step 390 after step 370.

[0103] An exemplary system utilizing Method 300 monitors the temperatures of sections within a battery pack enclosure and, in particular, battery cell temperatures. Method 300 employs a thermal model and monitored temperatures to detect temperature increases within a single section. These temperature increases could be due, for example, to a malfunctioning fan.

[0104] Method 300 then uses a flow model to determine the amount of flow increase required from one or more adjacent fans to move thermal energy away from the section where the temperature increase occurs. This facilitates maintaining a relatively constant temperature throughout the battery pack enclosure sections and can prevent temperatures from rising to undesirable levels due to thermal inertia.

[0105] It is understood that the outermost sections of the battery pack housing may be adjacent to a single fan, rather than being positioned directly between two fans. For example, section 64e in Fig. 4 is aligned with fan 68e and borders fan 68d. Section 64d in Fig. 4 is aligned with fan 68d and borders fans 68c and 68e.

[0106] If the temperature deviation occurs in an outermost section, the increase in flow from the directly adjacent fan may involve a doubling of the flow moved by the adjacent fan.

[0107] Features of some of the disclosed embodiments include a fan array for moving a flow through groups of battery cells. The fan array is part of a system that is smaller than prior art systems. The system of the present disclosure can have a reduced flow path length, resulting in a lower pressure drop and a reduction in noise, vibration, and roughness. The system of the present disclosure can reduce ductwork requirements compared to prior art designs, as well as potential leakage points for the flow. Furthermore, the fan array can compensate for the inability of one or more of its fans to move a sufficient flow.

[0108] The preceding description is exemplary and not limiting. Variations and modifications to the disclosed examples may be obvious to a person skilled in the art, which do not necessarily deviate from the essence of this disclosure. Therefore, the scope of protection of this disclosure can only be determined by considering the subsequent claims.

Claims

[1] Method (200) for controlling a flow by means of a battery set (14) comprising the following: in a first operating state, moving a flow through a first section (64a - 64e) of an enclosure (60) using a first fan (68a - 68e), and moving a flow through a second section (64a - 64e) of the enclosure (60) using a second fan (68a - 68e); in a second operating state, moving a flow through the second section (64a - 64e) using the first fan (68a - 68e); and Targeted supply of energy to a powertrain (10) of an electrified vehicle using a first group (18a - 18e) of battery cells within the first section (64a - 64e) and a second group (18a - 18e) of battery cells within the second section (64a - 64e); wherein the fans (68a - 68e) each include a reverse current blocking device (92), wherein in the first operating state the reverse current blocking device (92) is in a first position to allow the flow to leave the housing (60) through the fan (68a - 68e), and in the second operating state the reverse current blocking device (92) is in a second position to prevent the flow from entering the open area (80) through the fan (68a - 68e). [2] Method (200) according to claim 1, further comprising the change from the first operating state to the second operating state in response to a change in temperature. [3] Method (200) according to claim 2, wherein the change in temperature comprises the deviation of an actual temperature of the second section (64a - 64e) from an expected temperature of the second section (64a - 64e). [4] Method (200) according to claim 2, wherein the change in temperature comprises the deviation of an actual temperature of the second section (64a - 64e) from an average temperature of the battery set (14). [5] Method (200) for controlling a flow by means of a battery set (14) comprising the following: in a first operating state, moving a flow through a first section (64a - 64e) of an enclosure (60) using a first fan (68a - 68e), and moving a flow through a second section (64a - 64e) of the enclosure (60) using a second fan (68a - 68e); in a second operating state, moving a flow through the second section (64a - 64e) using the first fan (68a - 68e); and Change from the first operating state to the second operating state in response to a change in temperature, wherein the change in temperature comprises a change in the temperature of a group (18a - 18e) of battery cells within the second section (64a - 64e); wherein the Each fan (68a - 68e) includes a backflow preventer (92), wherein in the first operating state the backflow preventer (92) is in a first position to allow the flow to leave the housing (60) through the fan (68a - 68e), and in the second operating state the backflow preventer (92) is in a second position to prevent the flow from entering the open area (80) through the fan (68a - 68e). [6] Method (200) according to claim 2, further comprising, in the second operating state, adjusting the first fan (68a - 68e) to increase the flow moved by the first fan (68a - 68e). [7] Method (200) according to claim 6, wherein the adjustment is carried out in response to a difference between a temperature of battery cells in the second section (64a - 64e) and a temperature of battery cells in another area of ​​the housing (60). [8] Method (200) according to claim 6, wherein the adjustment is based on a flow model. [9] Method (200) according to claim 6, which further comprises, in the second operating state, moving a flow through the second section (64a - 64e) and a third section (64a - 64e) using a third fan (68a - 68e), wherein the second section (64a - 64e) is positioned between the first section (64a - 64e) and the third section (64a - 64e) within the enclosure (60). [10] Method (200) according to claim 1, wherein the first fan (68a - 68e) rotates about a first axis to move the flow, and the second fan (68a - 68e) rotates about a second axis to move the flow, the first axis aligning in a direction into which the flow is transferred through the first section (64a - 64e), and the second axis aligning in a direction into which the flow is transferred through the second section (64a - 64e). [11] Method (200) for controlling a flow by means of a battery set (14) comprising the following: Transferring a flow through a first section (64a - 64e) of an enclosure (60) using a first fan (68a - 68e), and transferring a flow through a second section (64a - 64e) of the enclosure (60) using a second fan (68a - 68e); Increasing the speed of the first fan (68a - 68e) to transfer the flow through the second section (64a - 64e), the first fan (68a - 68e) being used in response to a temperature change in the second section (64a - 64e); and Transfer of the flow through the second section (64a - 64e) and a third section (64a - 64e) using a third fan (68a - 68e), wherein the second section (64a - 64e) is positioned between the first section (64a - 64e) and the third section (64a - 64e) within the enclosure (60); and The fans (68a - 68e) each contain a backflow preventer (92), wherein in a first operating state the backflow preventer (92) is in a first position to allow the flow to leave the housing (60) through the fan (68a - 68e), and in a second operating state the backflow preventer (92) is in a second position to prevent the flow from entering the open area (80) through the fan (68a - 68e). [12] Method (200) according to claim 11, wherein the temperature change in the second section comprises the deviation of an actual temperature of the second section (64a - 64e) from an expected temperature of the second section (64a - 64e). [13] Method (200) according to claim 11, wherein the temperature change in the second section (64a - 64e) comprises a temperature increase of a group (18a - 18e) of battery cells in the second section (64a - 64e). [14] Method (200) according to claim 11, wherein the temperature change in the second section (64a - 64e) comprises the deviation of an actual temperature of the second section (64a - 64e) from an average temperature of the battery pack (14). [15] Method (200) according to claim 11, wherein the first fan (68a - 68e) rotates about a first axis to move the flow, and the second fan (68a - 68e) rotates about a second axis to move the flow, the first axis aligning in a direction into which the flow is transferred through the first section (64a - 64e), and the second axis aligning in a direction into which the flow is transferred through the second section (64a - 64e). [16] Method (200) according to claim 11, wherein the raising is based on a flow model. [17] Method (200) according to claim 11, wherein the increase further occurs in response to the fact that the second fan (68a - 68e) transmits an insufficient flow through the second section (64a - 64e).

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