SYSTEM AND METHOD FOR BATTERY COOLING

Abstract

Systems and methods for cooling the battery cells of a battery are described. The system can include a variety of slide valves to create multiple coolant flow paths through a battery pack, thereby reducing the temperature difference between the battery cells. A controller adjusts the positions of the slide valves according to the battery cell temperature.

Description

field of technology

[0001] This description relates to a method and a system for cooling a battery pack comprising a plurality of battery cells. In one example, the battery pack could be installed in an electric vehicle. General state of the art

[0002] An electric vehicle can include a traction battery to power the vehicle. The traction battery can comprise a multitude of battery cells. These multiple battery cells can include cells arranged in parallel and in series. The temperature of these battery cells can increase during charging and / or discharging. To ensure a long battery lifespan and charging capacity, it may be desirable to maintain each battery cell at a temperature equal to that of the other battery cells. In other words, it may be desirable to operate the battery cells with the smallest possible temperature difference across the multitude of battery cells.In one example, a method for controlling a battery pack temperature includes setting, via one or more controllers, a first valve position to direct a coolant flow to one of a plurality of battery pack coolant inlets in response to a battery cell temperature. Brief description

[0003] Battery cells within a battery can be cooled or heated to maintain a desired temperature. Operating the battery cells at or near the desired temperature can extend battery life and enable desired charge and discharge rates. A battery pack temperature control system can be used to maintain the battery cells at or near the desired temperature. This system, which can also be called a battery pack cooling system, may employ a heat exchanger to remove heat from the battery pack by circulating coolant past the battery cells. This arrangement works well for maintaining battery cells near a desired temperature, and improvements to the battery pack temperature control system can provide additional benefits for controlling battery cells at a specific temperature.

[0004] The inventor of the present invention has recognized the aforementioned problem and has developed a method for controlling a battery pack temperature, comprising: adjusting, via one or more controls, a first valve position to direct a coolant flow to one of a plurality of battery pack coolant inlets in response to a battery cell temperature.

[0005] By adjusting a primary valve position to direct coolant flow to one of a variety of battery pack coolant inlets in response to a battery cell temperature, it may be possible to reduce temperature differences between cells within a battery pack. For example, it may be possible to control the temperature of a battery cell located near a coolant outlet of the battery pack so that it is closer to the temperature of a battery cell located near a coolant inlet. Consequently, charge capacities and lifespans of battery cells within a battery pack can be maintained more uniformly.

[0006] The present description can offer several advantages. In particular, the approach can provide an extended battery pack lifespan. Furthermore, the approach can provide a more uniform charge distribution between battery cells, enabling battery cells to deliver larger amounts of charge to electrical power consumers. Moreover, the approach can provide a way for battery cells to receive higher charge rates for longer periods, thus reducing battery charging time.

[0007] The aforementioned advantages, as well as other advantages and features of the present description, will become readily apparent from the following detailed description, whether considered on its own or in conjunction with the accompanying drawings.

[0008] It is understood that the foregoing summary is provided to introduce, in simplified form, a selection of concepts that are further described in the detailed description. It is not intended to identify key features of the claimed subject matter, the scope of which is defined solely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that address any of the disadvantages mentioned above or in any part of this disclosure. Brief description of the drawings

[0009] The advantages described herein will become more fully apparent from reading an example of an embodiment, referred to in this document as the detailed description, either alone or with reference to the drawings, in which the following applies: Fig. Figure 1 is a schematic view of an example electric vehicle; Fig. Figure 2 is a schematic perspective view of an example battery pack; Fig. Section 3 presents diagrams of exemplary battery cell temperatures in the battery pack. Fig. 2 dar; Fig. Figure 4 shows a schematic view of an example battery cooling system; Fig. Figures 5A-5C show a sectional view of an inlet slide valve in three different operating states; Fig. Figures 5D-5F show a sectional view of an exhaust slide valve in three different operating states; Fig. 6A-6E display different operating modes for the battery cooling system. Fig. 4 dar; Fig. Figure 7 presents a flowchart of a procedure for operating the battery cooling system. Fig. 4 dar; and Fig. Figure 8 presents a flowchart of a second procedure for operating the battery cooling system. Fig. 4 dar. Detailed description

[0010] This description relates to a cooling system for a battery pack comprising a multitude of battery cells. The cooling system may include two slide valves that control the flow of coolant into and out of the battery pack. The cooling system also includes a controller and a control routine to reduce the differential temperature within the battery pack. The battery pack may be included in an electric vehicle, as shown in Fig. 1 shown. Fig. Figure 2 represents an exemplary coolant flow path through an exemplary battery pack and Fig. 3 presents battery cell temperature profiles for in Fig. The two illustrated battery cells represent the battery cells. A battery pack coolant system according to the present description is in Fig. 4 shown. Different positions of coolant flow control valves are shown in the Fig. 5A-5F are shown. Several coolant flow control modes for the coolant system. Fig. 4 are in the Fig. 6A-6E shown. A method for operating the battery pack cooling system made of Fig. 4 is in Fig. Figure 7 shows a second method for operating the battery pack cooling system. Fig. 4 is in Fig. 8 shown.

[0011] Fig. Figure 1 is a block diagram of an exemplary vehicle propulsion system 100 for a vehicle 121. A front section of the vehicle 121 is shown at 110 and a rear section of the vehicle 121 is shown at 111. The vehicle propulsion system 100 includes an electric machine 126. The electric machine 126 can consume or generate electrical power depending on its operating mode. Fig. 1. Mechanical connections between different components are illustrated as solid lines, whereas electrical connections between different components are illustrated as dashed lines.

[0012] The vehicle drive system 100 includes a rear axle 122. In some examples, the rear axle 122 may comprise two half-shafts, for example, a first half-shaft 122a and a second half-shaft 122b. The vehicle drive system 100 also has front wheels 130 and rear wheels 131. The rear wheels 131 can be driven by the electric machine 126.

[0013] The rear axle 122 is coupled to the electric machine 126. A rear drive unit 136 can transmit power from the electric machine 126 to the axle 122, causing the rear wheels 131 to rotate. The rear drive unit 136 can include a small gear 175 and a large gear 177, which are coupled to the electric machine 126 via an output shaft 126a. The small gear 175 can be engaged by fully closing a clutch 176 of the small gear. The large gear 177 can be engaged by fully closing a clutch 178 of the large gears. The clutch 178 of the large gears and the clutch 176 of the small gears can be opened and closed by commands received by the rear drive unit 136 via a Controller Area Network (CAN) 199.Alternatively, the clutch 178 of the large gear and the clutch 176 of the small gear can be opened and closed via digital outputs or pulse widths provided by a control system 114. The rear drive unit 136 can include differential gears 128 so that torque can be supplied to the first half-shaft 122a and the second half-shaft 122b. In some examples, an electrically controlled differential clutch (not shown) can be included in the rear drive unit 136.

[0014] The electric machine 126 can receive electrical power from an on-board electrical energy storage device (e.g., a traction battery or battery pack) 132. Furthermore, the electric machine 126 can provide a generator function to convert the vehicle's kinetic energy into electrical energy, which can be stored in the electrical energy storage device 132 for later use by the electric machine 126. An inverter system controller 134 (ISC1) can convert alternating current generated by the electric machine 126 into direct current for storage in the electrical energy storage device 132, and vice versa. The electric drive system 135 includes an electric machine 126 and an inverter system controller 134.The electrical energy storage device 132 can be a battery, a capacitor, an inductor, or another electrical energy storage device. Electrical power flowing into the electric drive system 135 can be monitored via a current sensor 145 and a voltage sensor 146. The position and rotational speed of the electric machine 126 can be monitored via a position sensor 147. The torque generated by the electric machine 126 can be monitored via a torque sensor 148.

[0015] The electric machine 126 can drive the vehicle 121 in a forward or reverse direction in response to a position of the gear selector 159. Furthermore, the vehicle 121 can enter the park position (e.g., no vehicle movement with the wheels locked) or neutral in response to a position of the gear selector 159.

[0016] In some examples, the electrical energy storage device 132 can be configured to store electrical energy that can be supplied via a high-voltage bus 195 (e.g., components such as conductors carrying electrical current and high voltage (e.g., a voltage of more than 60 volts)). The high-voltage bus 195 can communicate electrically with high-voltage vehicle auxiliary consumers (e.g., heat pump, air conditioner, heater, etc.) 186 and a power converter 191 (e.g., DC-to-DC converter or AC-to-DC converter). The power converter 191 is electrically coupled to an electrical socket 190 and the electrical socket 190 can be electrically connected to an external charging station 198 (e.g. a direct current fast charger (DCFC), a level 2 charging device (e.g. a 240-volt AC charging device) or a level 1 charging device (e.g.A 120-volt AC charging device is connected via a cable 193. The external charging station 198 includes a persistent (e.g., read-only) memory 198a, a random-access memory 198b, digital inputs / outputs 198c, and a microcontroller 198d. The power converter 191 can control the electrical current and voltage supplied to the electrical energy storage device 132. The power converter 191 can include a persistent (e.g., read-only) memory 191a, a random-access memory 191b, digital inputs / outputs 191c, and a microcontroller 191d. A socket sensor 197 provides information on whether the vehicle 121 is plugged into the external charging station 198 or not. The external charging station 198 is located outside the vehicle (e.g., is not part of the vehicle).The high-voltage bus 195 can also be electrically coupled to a DC / DC converter 184, which enables the transfer of electrical power from the high-voltage bus 195 to the low-voltage bus 196 (e.g., conductors, terminals, and other conductive connection devices). Thus, electrical power can be exchanged between the electrical energy storage device 132 and a low-voltage battery 182 (e.g., battery voltage of less than 20 volts). A low-voltage battery switch 185 can be selectively opened to prevent power from the low-voltage bus 196 from reaching the low-voltage battery 182 (e.g., 12 volts DC). The low-voltage bus 196 can distribute low-voltage electrical power to low-voltage electrical consumers 183 (e.g., electrical power consumers such as infotainment systems, windshield wipers, fans, etc.).

[0017] Again, in relation to Fig. Figure 1 includes the electrical energy storage device 132, a plurality of battery cells 137, a controller 139 for the electrical energy storage device, and a power distribution module 138. The controller 139 for the electrical energy storage device can provide charge balancing between energy storage elements (e.g., battery cells) and communication with other vehicle controllers (e.g., a controller 112). The power distribution module 138 controls the power flow into and out of the electrical energy storage device 132. A contactor 133 can selectively couple and decouple the electrical energy storage device 132 from the high-voltage bus 195 and the inverter system controller (ISC1) 134. In some examples, the contactor 133 may be located outside the electrical energy storage device 132.According to the illustration, the power distribution module 138 is also directly electrically coupled to the protected DC / DC converter 169.

[0018] A temperature control system 163 of the electrical energy storage device (e.g., a heat pump or heat exchanger) can include a temperature control actuator 164 (e.g., a pump, a valve, an electrical switch, etc.) to set a temperature of the electrical energy storage device. The temperature control system 163 of the electrical energy storage device can receive a requested temperature of the electrical energy storage device via a controller coupled to the CAN bus 199.

[0019] The control system 114 can communicate with the electric machine 126, the electrical energy storage device 132, a navigation system 187, etc. The control system 114 can receive sensory feedback information from the electric drive system 135 and the electrical energy storage device 132, etc. Furthermore, in response to this sensory feedback, the control system 114 can send control signals to the electric drive system 135 and the electrical energy storage device 132, etc. The control system 114 can receive an output request from the vehicle drive system from a human operator 102 or an autonomous controller. For example, the control system 114 can receive sensory feedback from a pedal position sensor 194, which communicates with a pedal 192. The pedal 192 can schematically refer to a driver-activated pedal.Similarly, the control system 114 can receive a signal for vehicle deceleration requested by an operator (e.g., user) via a human operator 102 or an autonomous control system. For example, the control system 114 can receive sensory feedback from a pedal position sensor 157, which communicates with a vehicle brake caliper control pedal 156.

[0020] One or more wheel speed sensors (WSS) 123 can be coupled to one or more wheels of the vehicle drive system 100. The wheel speed sensors can detect the rotational speed of each wheel. Such an example of a WSS can include a permanent magnet sensor.

[0021] The controller 112 can comprise a section of a control system 114. In some examples, the controller 112 can be the sole controller of the vehicle. As shown, the control system 114 receives information from a variety of sensors 116 (various examples of which are described here) and sends control signals to a variety of actuators 181 (various examples of which are described here). For example, the sensors 116 can include tire pressure sensors (not shown), wheel speed sensors 123, etc. In some examples, sensors associated with the electric machine 126, the wheel speed sensor 123, etc., can communicate information regarding various operating states of the electric machine to the controller 112. The controller 112 includes a persistent (e.g., read-only) memory 165, a random-access memory 166, digital inputs / outputs 168, and a microcontroller 167.The controller 112 can receive input data via CAN 199 and provide data to a human-machine interface 140. Additionally, the controller 112 can send vehicle data and receive command instructions (e.g., a request to prepare the vehicle for extended storage) via a transceiver 160 and a remote device 161 (e.g., mobile phone, tablet, or other remote wireless device). The remote device 161 can transmit commands and receive data via a cellular or satellite network 162.

[0022] With reference to Fig. Figure 2 shows a perspective, transparent example battery pack. The battery pack 132 is shown with a plurality of battery cells 137. In this example, the battery cells 137 are shown in the shape of a cylinder. The battery pack 132 includes a front 204 and a back 206. In this example, coolant flows in the direction indicated by arrows 210. Thus, coolant flows from a front to a back of the battery pack 132. A first battery cell 220 is located near the front 204 of the battery pack 132, and a second battery cell 222 is located near the back 206 of the battery pack 132. If coolant flows exclusively in the direction indicated by arrows 210, a temperature difference, as shown in Figure 2, can occur. Fig. 3 shown, develop between the first battery cell 220 and the second battery cell 222.

[0023] With reference to Fig. Figure 3 shows diagrams of exemplary battery cell temperature profiles. In particular, a diagram of the battery cell temperature versus time is shown, and the diagram includes two curves. The first curve, 302, represents the temperature of the second battery cell, 222, which is shown in Fig. 2 is shown, and the second curve 304 represents a temperature of the first battery cell 220, which is in Fig. Figure 2 shows that there is a temperature difference between the first curve 302 and the second curve 304. This temperature difference can occur when coolant flows into the battery pack 132, as shown in Figure 2. Fig. Figure 2 shows that it may be desirable to reduce the temperature difference so that the first curve 302 follows curve 304 more closely.

[0024] With reference to Fig. Figure 4 shows a schematic view of an exemplary temperature control system 163 for the electrical energy storage device (e.g., a battery pack temperature control system). In this example, the temperature control system 163 of the electrical energy storage device includes an inlet slide valve 408 and an outlet slide valve 436, which are shown outside a battery pack housing 410. In other examples, however, the inlet slide valve 408 and an outlet slide valve 436 may be located inside the battery pack housing 410. The temperature control system 163 of the electrical energy storage device also includes a coolant pump 402 for circulating battery coolant within a battery cooling system 400, a refrigeration unit 404, a coolant reservoir 406, and lines or passages 480-486.Coolant can flow through the pipes or passages in a direction indicated by the arrowheads. The refrigeration unit 404 can be fluid-coupled with a heat pump (not shown). The operation of the temperature control system 163 of the electrical energy storage device can be set via the temperature control system 434, which includes a persistent memory 434a (e.g., read-only memory), a random-access memory 434b, digital inputs / outputs 434c, and a microcontroller 434d. The temperature control system of the electrical energy storage device can receive temperature information in the form of data, voltage, or current via temperature sensors 434e.

[0025] A battery cell, described as cell A, is shown at 490. Battery cell A is shown at one end of a left side of the electrical energy storage device 132 (battery pack) and is located closer to an inlet side of the battery pack, where the first, second, and third inlets are located, than to an outlet side of the battery pack, where the first, second, and third outlets are located. The temperature control system 434 can monitor the temperature of cell A. A battery cell, described as cell B, is shown at 492. Battery cell B is shown at one end of a right side of the electrical energy storage device 132 (battery pack) and is located closer to an inlet side of the battery pack, where the first, second, and third inlets are located, than to an outlet side of the battery pack, where the first, second, and third outlets are located.The temperature control system 434 can monitor the temperature of cell B. A battery cell, described as cell M, is shown at 494. Battery cell M is shown midway between the left and right sides of the electrical energy storage device 132 (battery pack) and is located approximately midway between the inlet and outlet sides of the battery pack. The temperature control system 434 can monitor the temperature of cell M.

[0026] During operation, as in the Fig. As shown in Figures 5A-5F, the position of the inlet slide valve 408 and the outlet slide valve 436 can be adjusted to control the battery cell temperature and the flow direction of coolant flowing through the electrical energy storage device 132. In a first position, the inlet slide valve 408 can direct the coolant flow through a first coolant inlet 412a of the electrical energy storage device 132. In a second position, the inlet slide valve 408 can direct the coolant flow through a second coolant inlet 412b of the electrical energy storage device 132. In a third position, the inlet slide valve 408 can direct the coolant flow through a third coolant inlet 412c of the electrical energy storage device 132.In a first position, the outlet slide control valve 436 can direct the coolant flow through a first coolant outlet 440a of the electrical energy storage device 132. In a second position, the outlet slide control valve 436 can direct the coolant flow through a second coolant outlet 440b of the electrical energy storage device 132. In a third position, the outlet slide control valve 436 can direct the coolant flow through a third coolant outlet 440c of the electrical energy storage device 132.

[0027] Coolant can flow from pump 402 to inlet slide valve 408. Coolant exits inlet slide valve 408 and flows into electrical energy storage device 132. Coolant exits electrical energy storage device 132 and flows to outlet slide valve 436. Coolant can flow from outlet slide valve 436 to coolant reservoir 406. The coolant 407 can flow from coolant reservoir 406 to refrigeration unit 404 (e.g., a heat exchanger) before returning to pump 402, as indicated by the arrows that show the lines or passages.

[0028] With reference to the Fig. Figures 5A-5C show a cross-section of the inlet slide valve 408 in three different positions. These three positions allow the coolant flow through the electrical energy storage device 132 to be controlled. The inlet slide valve 408 includes a slide valve 502, a body 505, and an actuator 599 (e.g., an electrically actuated solenoid). The inlet slide valve 408 also includes a single inlet 510, a first outlet 512, a second outlet 514, and a third outlet 516. Fig. Figure 5A shows the inlet slide valve 408 in a first position, in which coolant can flow from the single inlet 510 and through the third outlet 516 via a first coolant flow path 503. Coolant cannot flow through the first and second outlets when the inlet slide valve 408 is in the first position. Fig. Figure 5B shows the inlet slide valve 408 in a second position, in which coolant can flow from the single inlet 510 and through the second outlet 514 via a second coolant flow path 504. Coolant cannot flow through the first and third outlets when the inlet slide valve 408 is in the second position. Fig. Figure 5C depicts the inlet slide valve 408 in a third position, in which coolant can flow from the single inlet 510 and through the first outlet 512 via a third coolant flow path 506. Coolant cannot flow through the second and third outlets when the inlet slide valve 408 is in the third position.

[0029] With reference to the Fig. Figures 5D-5F show a cross-section of the outlet slide valve 436 in three different positions. These three positions allow the coolant flow from the electrical energy storage device 132 to be controlled. The outlet slide valve 436 includes a slide valve 509, a body 560, and an actuator 511 (e.g., an electrically actuated solenoid). The outlet slide valve 436 also includes a single outlet 520, a first inlet 522, a second inlet 524, and a third inlet 526. Fig. Figure 5D shows the exhaust valve control valve 436 in a first position, in which coolant can flow from the first inlet 522 to the single outlet 520 via a first coolant flow path 530. Coolant cannot flow through the second and third inlets when the exhaust valve control valve 436 is in the first position. Fig. Figure 5E represents the exhaust valve control valve 436 in a second position, in which coolant can flow from the second inlet 524 through the single outlet 520 via a second coolant flow path 531. Coolant cannot flow through the first and third inlets when the exhaust valve control valve 436 is in the second position. Fig. Figure 5F depicts the exhaust valve control 436 in a third position, in which coolant can flow from the third inlet 526 and through the single outlet 520 via a third coolant flow path 532. Coolant cannot flow through the first and second inlets when the exhaust valve control 436 is in the third position.

[0030] With reference to Fig. Figure 6A shows the temperature control system 163 of the electrical energy storage device in configuration A, where coolant flows as indicated by the line arrows. In this configuration, the inlet slide valve 408 is operated in its first position, allowing coolant to flow from pump 402 into the third coolant inlet 412c. Furthermore, the outlet slide valve 436 is operated in its first position, allowing coolant to flow from the first coolant outlet 440a to the reservoir 406.

[0031] With reference to Fig. Figure 6B shows the temperature control system 163 of the electrical energy storage device in configuration B, where coolant flows as indicated by the line arrows. In this configuration, the inlet slide valve 408 is operated in its third position, allowing coolant to flow from pump 402 into the first coolant inlet 412a. Furthermore, the outlet slide valve 436 is operated in its third position, allowing coolant to flow from the third coolant outlet 440c to the reservoir 406.

[0032] With reference to Fig. Figure 6C shows the temperature control system 163 of the electrical energy storage device in configuration M1, where coolant flows as indicated by the line arrows. In this configuration, the inlet slide valve 408 is operated in its second position, allowing coolant to flow from pump 402 into the second coolant inlet 412b. Furthermore, the outlet slide valve 436 is operated in its second position, allowing coolant to flow from the second coolant outlet 440b to the reservoir 406.

[0033] With reference to Fig. Figure 6D shows the temperature control system 163 of the electrical energy storage device in configuration M2, where coolant flows as indicated by the line arrows. In this configuration, the inlet slide valve 408 is operated in its second position, allowing coolant to flow from pump 402 into the second coolant inlet 412b. Furthermore, the outlet slide valve 436 is operated in its first position, allowing coolant to flow from the first coolant outlet 440a to the reservoir 406.

[0034] With reference to Fig. Figure 6E shows the temperature control system 163 of the electrical energy storage device in configuration M3, where coolant flows as indicated by the line arrows. In this configuration, the inlet slide valve 408 is operated in its second position, allowing coolant to flow from pump 402 into the second coolant inlet 412b. Furthermore, the outlet slide valve 436 is operated in its third position, allowing coolant to flow from the third coolant outlet 440c to the reservoir 406.

[0035] The coolant flow paths in configurations A, B, M1, M2 and M3 are indicated by arrows 602-610 in the Fig. Figures 6A-6E are shown. These coolant flow paths make it possible to cool the different battery cells at different rates according to their battery cell temperatures.

[0036] The system from the Fig. 1-6E provides a battery pack temperature control system comprising: an inlet slide valve; an outlet slide valve; a plurality of coolant inlets; a plurality of coolant outlets; a plurality of battery cells; and one or more controllers containing executable instructions stored in a control memory, which cause the one or more controllers to adjust the inlet slide valve and the outlet slide valve in response to the temperature of one or more of the plurality of battery cells. In a first example, the system includes the ability to adjust the inlet slide valve to three different positions to provide three different flow paths through the inlet slide valve.In a second example, which may include the first example, the system involves the exhaust slide valve being adjustable to three different positions to provide three different flow paths through the exhaust slide valve. In a third example, which may include one or both of the first and second examples, the system involves the inlet slide valve being in fluid communication with the multiple coolant inlets. In a fourth example, which may include one or more of the first through third examples, the system involves the exhaust slide valve being in fluid communication with the multiple coolant outlets. In a fifth example, which may include one or more of the first through fourth examples, the system involves the multiple battery cells being contained within a housing.In a sixth example, which may include one or more of the first through fifth examples, the system further includes additional executable instructions for operating the battery pack temperature control system in five different cooling configurations. In a seventh example, which may include one or more of the first through sixth examples, the system includes the fact that the five different cooling configurations are based on different positions of the inlet slide valve control valve and different positions of the outlet slide valve control valve.

[0037] The system from the Fig. 1-6E provides a battery pack temperature control system comprising: an inlet slide valve; an outlet slide valve; a plurality of coolant inlets; a plurality of coolant outlets; a coolant pump; a coolant reservoir; a plurality of battery cells enclosed in a housing; and one or more controllers containing executable instructions stored in a control memory, which cause the one or more controllers to adjust the inlet slide valve and the outlet slide valve to produce a plurality of different coolant flow paths through the housing. In a first example, the battery pack temperature control system further includes additional instructions to adjust the speed of the coolant pump in response to the temperature of one of the plurality of battery cells.In a second example, which may include the first example, the battery pack temperature control system includes the plurality of coolant inlets arranged along a first side of the enclosure. In a third example, which may include one or both of the first and second examples, the battery pack temperature control system includes the plurality of coolant outlets arranged along a second side of the enclosure. In a fourth example, which may include one or more of the first through third examples, the battery pack temperature control system further includes a chiller, wherein the chiller is in fluid communication with the coolant pump and the coolant reservoir.

[0038] With reference to Fig. Figure 7 describes a method for controlling the temperature of a battery pack. At least parts of the method can be implemented as executable instructions stored in persistent memory of one or more controllers. Furthermore, some parts of the method can be actions performed in the physical world via the one or more controllers and the one or more actuators. The method can be implemented in the systems from the Fig. 1 and Fig. 4 includes his.

[0039] In version 702, procedure 700 operates the battery pack temperature control system in configuration A, as shown in Fig. Figure 6A shows the temperature control system of the electrical energy storage device. In configuration A, the temperature control system of the electrical energy storage device is operated with the inlet slide valve 408 in a first position and the outlet slide valve 436 in a third position, such that coolant flows from the third coolant inlet 412c (e.g., a coolant inlet on a right side) of the electrical energy storage device to a first coolant outlet 440a, as indicated by the arrows in Figure 6A. Fig. 6A is specified. This allows battery cells to be cooled by coolant in one direction, from right to left. Furthermore, method 700 can adjust the speed of a coolant pump in response to a battery cell temperature. Method 700 transitions to 704.

[0040] In procedure 704, procedure 700 assesses whether the temperature of battery cell A minus the temperature of battery cell B is greater than or equal to a first threshold temperature. If so, the answer is yes, and procedure 700 proceeds to 706. Otherwise, the answer is no, and procedure 700 proceeds to 716.

[0041] In the 706, procedure 700 operates the battery pack temperature control system in configuration B, as shown in Fig. Figure 6B is shown. In configuration B, the temperature control system of the electrical energy storage device is operated with the inlet slide valve 408 in a third position and the outlet slide valve 436 in a first position, so that coolant flows from the first coolant inlet 412a (e.g., a coolant inlet on a left side) of the electrical energy storage device to a third coolant outlet 440c, as indicated by the arrows in Fig. 6B is specified. This allows battery cells to be cooled by coolant in a left-to-right direction. Furthermore, method 700 can adjust the speed of a coolant pump in response to a battery cell temperature. Method 700 transitions to 708.

[0042] In procedure 708, procedure 700 assesses whether the temperature of battery cell B minus the temperature of battery cell A is greater than or equal to a second threshold temperature. If so, the answer is yes, and procedure 700 returns to 702. Otherwise, the answer is no, and procedure 700 proceeds to 710.

[0043] In procedure 710, procedure 700 assesses whether the temperature of battery cell M minus a larger value than the temperature of battery cell A or the temperature of battery cell B is greater than or equal to zero. If so, the answer is yes, and procedure 700 proceeds to 712. Otherwise, the answer is no, and procedure 700 returns to 706.

[0044] In the 712, procedure 700 operates the battery pack temperature control system in configuration M1, as shown in Fig. Figure 6C is shown. In configuration M1, the temperature control system of the electrical energy storage device is operated with the inlet slide valve 408 in a second position and the outlet slide valve 436 in a second position, so that coolant flows from the second coolant inlet 412b (e.g., a middle coolant inlet) of the electrical energy storage device to a second coolant outlet 440b, as indicated by the arrows in Fig. 6C is specified. This allows battery cells to be cooled by coolant in a center-to-center flow direction. Furthermore, method 700 can adjust the speed of a coolant pump in response to a battery cell temperature. Method 700 transitions to 714.

[0045] In case 714, procedure 700 assesses whether the temperature of battery cell M minus a larger value than the temperature of battery cell A or the temperature of battery cell B is greater than or equal to zero. If so, the answer is yes, and procedure 700 returns to 712. Otherwise, the answer is no, and procedure 700 returns to 706.

[0046] In case 716, procedure 700 assesses whether the temperature of battery cell M minus a larger value than the temperature of battery cell A or the temperature of battery cell B is greater than or equal to zero. If so, the answer is yes, and procedure 700 proceeds to 718. Otherwise, the answer is no, and procedure 700 returns to 702.

[0047] In the 718, the 700 procedure operates the battery pack temperature control system in configuration M, as shown in Fig. Figure 6C is shown. In configuration M1, the temperature control system of the electrical energy storage device is operated with the inlet slide valve 408 in a second position and the outlet slide valve 436 in a second position, so that coolant flows from the second coolant inlet 412b (e.g., a middle coolant inlet) of the electrical energy storage device to a second coolant outlet 440b, as indicated by the arrows in Fig. 6C is specified. This allows battery cells to be cooled by coolant in a center-to-center flow direction. Furthermore, method 700 can adjust the speed of a coolant pump in response to battery cell temperature. Method 700 transitions to 720.

[0048] At 720, procedure 700 assesses whether the temperature of battery cell M minus a larger value than the temperature of battery cell A or the temperature of battery cell B is greater than or equal to zero. If so, the answer is yes, and procedure 700 returns to 718. Otherwise, the answer is no, and procedure 700 returns to 702.

[0049] Thus, the procedure is Fig. 7. Changing the direction of a coolant flow through a battery pack in response to battery cell temperatures, thus reducing the temperature difference between battery cells. Furthermore, the method demonstrates Fig. 7. Change which battery pack coolant inlets and outlets receive flowing coolant so that the temperature difference between battery cells can be reduced. These measures can extend the lifespan of the battery cells and current charge and discharge capacities.

[0050] With reference to Fig. Figure 8 presents a second method for controlling the temperature of a battery pack. At least parts of Method 800 can be implemented as executable instructions stored in persistent memory of one or more controllers. Furthermore, some parts of Method 800 can be actions performed in the physical world via the one or more controllers and the one or more actuators. Method 800 can be implemented in the systems from the Fig. 1 and Fig. 4 includes it. Moreover, the procedure can consist of Fig. 8 simultaneously with the procedure from Fig. 7 can be carried out and the measures of the procedure can be derived from Fig. 8. Priority over those determined by the procedure Fig. 7 measures have been carried out. For example, if one of steps 804 and 810 is carried out, the procedure may be terminated. Fig. 7 takes no action.

[0051] In procedure 802, procedure 800 assesses whether the temperature of battery cell A is greater than a third threshold temperature. If so, procedure 800 proceeds to 804. Otherwise, the answer is no, and procedure 800 proceeds to 806.

[0052] In the 804, the 800 procedure operates the battery pack temperature control system in configuration M2, as shown in Fig. Figure 6D shows the temperature control system of the electrical energy storage device in M2, with the inlet slide valve 408 in a second position and the outlet slide valve 436 in a first position. This allows coolant to flow from the second coolant inlet 412b (e.g., a middle coolant inlet) of the electrical energy storage device to a first coolant outlet 440a, as indicated by the arrows in Figure 6D. Fig. 6D is specified. This allows battery cells on the left side of the battery pack to be primarily cooled by coolant. Procedure 800 is now complete.

[0053] In procedure 806, procedure 800 assesses whether the temperature of battery cell B is greater than a fourth threshold temperature. If so, procedure 800 proceeds to 810. Otherwise, the answer is no, and procedure 800 proceeds to 808.

[0054] In the 810, the 800 procedure operates the battery pack temperature control system in configuration M3, as shown in Fig. Figure 6E shows the temperature control system of the electrical energy storage device in configuration M3, with the inlet slide valve 408 in a second position and the outlet slide valve 436 in a third position, so that coolant flows from the second coolant inlet 412b (e.g., a middle coolant inlet) of the electrical energy storage device to a third coolant outlet 440c, as indicated by the arrows in Figure 6E. Fig. 6E is specified. This allows battery cells on the right side of the battery pack to be primarily cooled by coolant. Procedure 800 is now complete.

[0055] At 808, procedure 800 retains the currently active configuration for the temperature control system 163 of the electrical energy storage device if the temperature control system 163 of the electrical energy storage device has not recently been operated in the M2 or M3 configuration. However, if the temperature control system 163 of the electrical energy storage device has recently been operated in the M2 or M3 configuration, procedure 800 changes the temperature control system 163 of the electrical energy storage device to configuration A. Procedure 800 then terminates.

[0056] Thus, if the temperature of battery cell A exceeds a threshold, the coolant flow to battery cell A is prioritized, allowing battery cell A to be cooled first. Conversely, if the temperature of battery cell B exceeds a threshold, the coolant flow to battery cell B is prioritized, allowing battery cell B to be cooled first.

[0057] Thus, the procedures from the Fig. 7 and Fig.8. A method for controlling a battery pack temperature is provided, comprising: adjusting, via one or more controls, a first valve position to direct a coolant flow to one of a plurality of battery pack coolant inlets in response to a battery cell temperature. In a first example, the method further comprises adjusting a second valve position to direct a coolant flow to one of a plurality of battery pack coolant outlets in response to the battery cell temperature. In a second example, which may include the first example, the method comprises the plurality of battery pack coolant inlets comprising a first coolant inlet, a second coolant inlet, and a third coolant inlet.In a third example, which may include one or both of the first and second examples, the method involves the plurality of battery pack coolant outlets comprising a first coolant outlet, a second coolant outlet, and a third coolant outlet. In a fourth example, which includes one or more of the first through third examples, the method involves the first valve position being a position of a slide valve. In a fifth example, which includes one or more of the first through fourth examples, the method involves the battery cell temperature being a temperature difference between a first battery cell and a second battery cell. In a sixth example, which may include one or more of the first through fifth examples, the method further involves adjusting the speed of a coolant pump in response to the battery cell temperature.

[0058] The procedures and routines disclosed herein can be stored as executable instructions in persistent memory and can be executed by a control system that includes the controller in combination with the various sensors and actuators. Furthermore, parts of the procedures can be physical actions taken in the real world to change the state of a device. The specific routines described herein can represent one or more of any number of processing strategies, such as event-driven, interrupt-driven, multitasking, multithreading, and the like. Accordingly, various illustrated actions, operations, and / or functions can be performed in the illustrated sequence or in parallel, or in some cases, omitted.Similarly, the processing sequence is not strictly necessary to achieve the features and benefits of the examples described in this document, but is provided to facilitate illustration and description. One or more of the illustrated actions, processes, and / or functions can be performed repeatedly, depending on the specific strategy employed. Furthermore, the described actions, processes, and / or functions can graphically represent code to be programmed into non-transient memory on the computer-readable storage medium within the system. The described actions are executed by carrying out the instructions in a system that incorporates the various hardware components in combination with the electronic control. One or more of the procedural steps described in this document can be omitted if desired.

[0059] Although various embodiments have been described above, it is understood that these are presented as examples and not to limit or restrict the possibilities. It is understood that the configurations and routines disclosed in this document are exemplary and that these specific examples are not to be interpreted in a limiting sense, as numerous variations are possible. For example, the technology described above can be applied to powertrains incorporating different types of power sources, including different types of electric machines, internal combustion engines, and / or transmissions.The technology can be used independently or in combination with other power transmission systems, which are not limited to machines and drive systems for tandem axles, electric trailer axles, P4 axles, HEVs, BEVs, agricultural, marine, motorcycle, motorhomes, and on- and off-highway vehicles, by way of example. The subject matter of this disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations, as well as other features, functions, and / or properties disclosed herein. It is apparent to the person skilled in the art that the disclosed subject matter can be implemented in other specific forms without deviating from its essence.

[0060] The following claims highlight specific combinations and subcombinations that are considered novel and not obvious. These claims may refer to "one" element, "a first" element, or the equivalent thereof. Such claims may be understood to include one or more such elements and neither require nor exclude two or more such elements. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amending the present claims or by filing new claims in this or a related application.Such patent claims, regardless of whether they have a broader, narrower, the same, or different scope compared to the original patent claims, are also considered to be included in the subject matter of the present disclosure. As used in this document, the term "approximately" is to be understood as plus or minus five percent of the respective scope, unless otherwise specified.

[0061] According to the present invention, a method for controlling a battery pack temperature comprises: adjusting, via one or more controllers, a first valve position to direct a coolant flow to one of a plurality of battery pack coolant inlets in response to a battery cell temperature.

[0062] In one aspect of the invention, the method involves adjusting a second valve position to direct a coolant flow to one of a plurality of battery pack coolant outlets in response to the battery cell temperature.

[0063] In one aspect of the invention, the plurality of battery pack coolant inlets includes a first coolant inlet, a second coolant inlet, and a third coolant inlet.

[0064] In one aspect of the invention, the plurality of battery pack coolant outlets includes a first coolant outlet, a second coolant outlet, and a third coolant outlet.

[0065] In one aspect of the invention, the first valve position is a position of a slide valve.

[0066] In one aspect of the invention, the battery cell temperature is a temperature difference between a first battery cell and a second battery cell.

[0067] In one aspect of the invention, the method involves adjusting the speed of a coolant pump in response to the battery cell temperature.

[0068] According to the present invention, a battery pack temperature control system is provided comprising: an inlet slide valve; an outlet slide valve; a plurality of coolant inlets; a plurality of coolant outlets; a plurality of battery cells; and one or more controllers comprising executable instructions stored in a control memory which cause the one or more controllers to adjust the inlet slide valve and the outlet slide valve in response to a temperature of one or more of the plurality of battery cells.

[0069] According to one embodiment, the inlet slide valve can be set to three different positions to provide three different flow paths through the inlet slide valve.

[0070] According to one embodiment, the outlet slide valve can be set to three different positions to provide three different flow paths through the outlet slide valve.

[0071] According to one embodiment, the inlet slide valve control valve is in fluid communication with the plurality of coolant inlets.

[0072] According to one embodiment, the outlet slide control valve is in fluid communication with the plurality of coolant outlets.

[0073] According to one embodiment, the multitude of battery cells are contained in a housing.

[0074] According to one embodiment, the invention is further characterized by additional executable instructions for operating the battery pack temperature control system in five different cooling configurations.

[0075] According to one embodiment, the five different cooling configurations are based on different positions of the inlet slide valve and different positions of the outlet slide valve.

[0076] According to the present invention, a battery pack temperature control system is provided comprising: an inlet slide valve; an outlet slide valve; a plurality of coolant inlets; a plurality of coolant outlets; a coolant pump; a coolant reservoir; a plurality of battery cells enclosed in a housing; and one or more controllers containing executable instructions stored in a control memory, which cause the one or more controllers to adjust the inlet slide valve and the outlet slide valve to generate a plurality of different coolant flow paths through the housing.

[0077] According to one embodiment, the invention is further characterized by additional instructions to adjust the rotational speed of the coolant pump in response to the temperature of one of the plurality of battery cells.

[0078] According to one embodiment, the plurality of coolant inlets is arranged along a first side of the housing.

[0079] According to one embodiment, the multitude of coolant outlets are arranged along a second side of the housing.

[0080] According to one embodiment, the invention is further characterized by a refrigeration machine, wherein the refrigeration machine is in fluid communication with the coolant pump and the coolant reservoir.

Claims

[1] Method for controlling a battery pack temperature, comprising: Setting, via one or more controls, a first valve position to direct a coolant flow to one of a variety of battery pack coolant inlets in response to a battery cell temperature. [2] Method according to claim 1, further comprising adjusting a second valve position to direct a coolant flow to one of a plurality of battery pack coolant outlets in response to the battery cell temperature. [3] Method according to claim 2, wherein the plurality of battery pack coolant inlets includes a first coolant inlet, a second coolant inlet and a third coolant inlet. [4] Method according to claim 3, wherein the plurality of battery pack coolant outlets includes a first coolant outlet, a second coolant outlet and a third coolant outlet. [5] Method according to claim 1, wherein the first valve position is a position of a slide valve. [6] Method according to claim 1, wherein the battery cell temperature is a temperature difference between a first battery cell and a second battery cell. [7] Method according to claim 1, further comprising adjusting the rotational speed of a coolant pump in response to the battery cell temperature. [8] Battery pack temperature control system, comprising: an inlet slide valve control valve; an exhaust valve control valve; a large number of coolant inlets; a large number of coolant outlets; a large number of battery cells; and one or more controllers containing executable instructions stored in a control memory, which cause the one or more controllers to adjust the inlet slide valve and the outlet slide valve in response to a temperature of one or more of the plurality of battery cells. [9] Battery pack temperature control system according to claim 8, wherein the inlet slide control valve can be set to three different positions to provide three different flow paths through the inlet slide control valve. [10] Battery pack temperature control system according to claim 9, wherein the outlet slide control valve can be set to three different positions to provide three different flow paths through the outlet slide control valve. [11] Battery pack temperature control system according to claim 8, wherein the inlet slide control valve is in fluid communication with the plurality of coolant inlets. [12] Battery pack temperature control system according to claim 8, wherein the outlet slide control valve is in fluid communication with the plurality of coolant outlets. [13] Battery pack temperature control system according to claim 8, wherein the plurality of battery cells is contained in a housing. [14] Battery pack temperature control system according to claim 8, further comprising additional executable instructions to operate the battery pack temperature control system in five different cooling configurations. [15] Battery pack temperature control system according to claim 14, wherein the five different cooling configurations are based on different positions of the inlet slide valve control valve and different positions of the outlet slide valve control valve.

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