Abstract:
A vehicle charging station according to an exemplary aspect of the present disclosure includes, among other things, a cooling system configured to communicate a cooling airflow to a portion of a thermal management system located onboard an electrified vehicle, the cooling system including a fan and a chiller assembly.

Description:
TECHNICAL FIELD 
       [0001]    This disclosure relates to a vehicle charging station for charging a battery pack of an electrified vehicle. The charging station includes a cooling system configured to communicate cooling airflow toward the electrified vehicle to augment battery pack cooling during certain conditions. 
       BACKGROUND 
       [0002]    The need to reduce automotive fuel consumption and emissions is well known. Therefore, vehicles are being developed that reduce or completely eliminate reliance on internal combustion engines. Electrified vehicles are one type of vehicle currently being developed for this purpose. In general, electrified vehicles differ from conventional motor vehicles because they are selectively driven by one or more battery powered electric machines. Conventional motor vehicles, by contrast, rely exclusively on the internal combustion engine to drive the vehicle. 
         [0003]    A high voltage battery pack typically powers the electric machines and other electrical loads of the electrified vehicle. The battery pack includes a plurality of battery cells that must be periodically recharged to replenish the energy necessary to power these loads. An infrastructure of easily accessible charging stations is needed for charging the battery packs of electrified vehicles. 
       SUMMARY 
       [0004]    A vehicle charging station according to an exemplary aspect of the present disclosure includes, among other things, a cooling system configured to communicate a cooling airflow to a portion of a thermal management system located onboard an electrified vehicle, the cooling system including a fan and a chiller assembly. 
         [0005]    In a further non-limiting embodiment of the foregoing vehicle charging station, the cooling system is housed inside a housing of the vehicle charging station. 
         [0006]    In a further non-limiting embodiment of either of the foregoing vehicle charging stations, the housing includes a vent and the cooling airflow is communicated through the vent to a location external to the housing. 
         [0007]    In a further non-limiting embodiment of any of the foregoing vehicle charging stations, the chiller assembly includes a heat exchanger, and the fan is configured to communicate airflow across the heat exchanger to generate the cooling airflow. 
         [0008]    In a further non-limiting embodiment of any of the foregoing vehicle charging stations, the chiller assembly includes a compressor, a first heat exchanger, an expansion valve and a second heat exchanger. 
         [0009]    In a further non-limiting embodiment of any of the foregoing vehicle charging stations, the first heat exchanger is a condenser and the second heat exchanger is an evaporator. 
         [0010]    In a further non-limiting embodiment of any of the foregoing vehicle charging stations, a controller is configured to control operation of the cooling system. 
         [0011]    In a further non-limiting embodiment of any of the foregoing vehicle charging stations, the controller is configured to command operation of the cooling system during DC fast charging events. 
         [0012]    In a further non-limiting embodiment of any of the foregoing vehicle charging stations, a charging cord extends to a location outside of a housing of the vehicle charging station. 
         [0013]    In a further non-limiting embodiment of any of the foregoing vehicle charging stations, the cooling system is powered by an external power source. 
         [0014]    A method according to another exemplary aspect of the present disclosure includes, among other things, augmenting cooling of a battery pack of an electrified vehicle during a DC fast charging event. The step of augmenting cooling includes communicating a cooling airflow from a cooling system of a charging station across a component of a thermal management system of the electrified vehicle. 
         [0015]    In a further non-limiting embodiment of the foregoing method, the component of the thermal management system includes a cooling pack. 
         [0016]    In a further non-limiting embodiment of either of the foregoing methods, the cooling pack includes a radiator, a condenser, or both. 
         [0017]    In a further non-limiting embodiment of any of the foregoing methods, the method includes communicating the cooling airflow through a vent of a housing of the charging station. 
         [0018]    In a further non-limiting embodiment of any of the foregoing methods, the method includes communicating the cooling airflow if a charging cord of the charging station is plugged into a charging port of the electrified vehicle. 
         [0019]    In a further non-limiting embodiment of any of the foregoing methods, the method includes continuing to communicate the cooling airflow after the DC fast charge event has ended. 
         [0020]    In a further non-limiting embodiment of any of the foregoing methods, the cooling system includes a fan and a chiller assembly. 
         [0021]    In a further non-limiting embodiment of any of the foregoing methods, the chiller assembly includes a compressor, a first heat exchanger, an expansion valve and a second heat exchanger. 
         [0022]    In a further non-limiting embodiment of any of the foregoing methods, the method includes blowing airflow across a heat exchanger of the cooling system to generate the cooling airflow. 
         [0023]    In a further non-limiting embodiment of any of the foregoing methods, the airflow loses heat to a coolant circulated inside the heat exchanger as the airflow is communicated across the heat exchanger. 
         [0024]    The embodiments, examples and alternatives of the preceding paragraphs, the claims, or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments, unless such features are incompatible. 
         [0025]    The various features and advantages of this disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]      FIG. 1  schematically illustrates a powertrain of an electrified vehicle. 
           [0027]      FIG. 2  illustrates a vehicle charging station for charging a battery pack of an electrified vehicle. 
           [0028]      FIG. 3  illustrates an exemplary cooling system of a vehicle charging station. 
       
    
    
     DETAILED DESCRIPTION 
       [0029]    This disclosure describes a vehicle charging station for charging an energy storage device (e.g., a battery pack) of an electrified vehicle. The vehicle charging station includes a cooling system configured to communicate cooling airflow toward an electrified vehicle connected to the vehicle charging station to augment battery pack cooling, such as during DC fast charging events. The cooling system may include a chiller assembly and a fan for generating and communicating the cooling airflow. These and other features are discussed in greater detail in the following paragraphs of this detailed description. 
         [0030]      FIG. 1  schematically illustrates a powertrain  10  of an electrified vehicle  12 . Although depicted as a battery electric vehicle (BEV), it should be understood that the concepts described herein are not limited to BEV&#39;s and could extend to other electrified vehicles, including but not limited to, plug-in hybrid electric vehicles (PHEV&#39;s). Therefore, although not shown in this embodiment, the electrified vehicle  12  could be equipped with an internal combustion engine that can be employed either alone or in combination with other energy sources to propel the electrified vehicle  12 . 
         [0031]    In one non-limiting embodiment, the electrified vehicle  12  is a full electric vehicle propelled solely through electric power, such as by an electric machine  14 , without assistance from an internal combustion engine. The electric machine  14  may operate as an electric motor, an electric generator, or both. The electric machine  14  receives electrical power and provides a rotational output power. The electric machine  14  may be connected to a gearbox  16  for adjusting the output torque and speed of the electric machine  14  by a predetermined gear ratio. The gearbox  16  is connected to a set of drive wheels  18  by an output shaft  20 . A high voltage bus  22  electrically connects the electric machine  14  to a battery pack  24  through an inverter  26 . The electric machine  14 , the gearbox  16 , and the inverter  26  are collectively referred to as a transmission  28 . 
         [0032]    The battery pack  24  is an exemplary electrified vehicle battery. The battery pack  24  may be a high voltage traction battery pack that includes a plurality of battery assemblies  25  (i.e., battery arrays or groupings of battery cells) capable of outputting electrical power to operate the electric machine  14  and/or other electrical loads of the electrified vehicle  12 . Other types of energy storage devices and/or output devices can also be used to electrically power the electrified vehicle  12 . 
         [0033]    The electrified vehicle  12  may also include a charging system  30  for charging the energy storage devices (e.g., battery cells) of the battery pack  24 . The charging system  30  may be connected to an external power source (not shown) for receiving and distributing power. The charging system  30  may also be equipped with power electronics used to convert AC power received from the external power supply to DC power for charging the energy storage devices of the battery pack  24 . The charging system  30  may also accommodate one or more conventional voltage sources from the external power supply (e.g., 110 volt, 220 volt, etc.). 
         [0034]    The powertrain  10  shown in  FIG. 1  is highly schematic and is not intended to limit this disclosure. Various additional components could alternatively or additionally be employed by the powertrain  10  within the scope of this disclosure. 
         [0035]      FIG. 2  is a highly schematic depiction of a vehicle charging station  32  that may be employed to charge an energy storage device, such as the battery pack  24  of electrified vehicle  12 . The electrified vehicle  12  is shown parked in proximity to the vehicle charging station  32 . The various components of the vehicle charging station  32  and the electrified vehicle  12  are shown schematically to better illustrate the features of this disclosure and are not necessarily depicted in their exact locations and configurations within the vehicle charging station  32  and the electrified vehicle  12 , respectively. It should further be understood that the components depicted in  FIG. 2  are not necessarily drawn to scale. 
         [0036]    The vehicle charging station  32  may be connected to the electrified vehicle  12  to charge the battery pack  24 . In one non-limiting embodiment, the vehicle charging station  32  is configured to perform DC fast charging of the battery pack  24 . DC fast charging events are immediate, rapid charge events that typically last approximately thirty minutes or less. The vehicle charging station  32  may employ DC fast charging by delivering direct current at power rates between approximately 50 A and 500 A at between 200 V and 600 V to rapidly charge the battery pack  24 , as opposed to the typical 4 A to 15 A output of standard alternating current chargers. 
         [0037]    The vehicle charging station  32 , including its various components, may be powered by an external power source  42  (shown schematically). In one non-limiting embodiment, the external power source  42  is utility grid power. In another non-limiting embodiment, the external power source  42  includes an alternative energy source, such as solar power, wind power, etc. In yet another non-limiting embodiment, the external power source  42  includes a combination of utility grid power and alternative energy sources. 
         [0038]    The exemplary vehicle charging station  32  may include a housing  34 , a controller  36 , a charging cord  38  and a cooling system  40 . The controller  36  and the cooling system  40  are housed inside the housing  34 , whereas the charging cord  38  may extend outside of the housing  34  for connecting to the electrified vehicle  12 . Although not shown, the housing  34  could include one or more output displays for displaying information to an occupant of the electrified vehicle  12 . 
         [0039]    The controller  36  is configured to control the amount of charge supplied from the vehicle charging station  32  to the battery pack  24 , such as during a DC fast charging event. For example, the controller  36  may control the amount of voltage and current that is supplied during the DC fast charging event as well as the length of the charge, among other parameters. The controller  36  may also communicate with the various control systems of the electrified vehicle  12  for monitoring or otherwise controlling the DC fast charging event. 
         [0040]    The controller  36  may be equipped with various power electronics for controlling the charging-related tasks. For example, in one non-limiting embodiment, the controller  36  converts alternating current (AC) received from the external power source  42  to direct current (DC) for DC fast charging the battery pack  24 . In yet another non-limiting embodiment, as is discussed in greater detail below, the controller  36  may additionally control operation of the cooling system  40  for selectively directing cooling airflow  48  toward the electrified vehicle  12  during DC fast charging events. 
         [0041]    The charging cord  38  of the vehicle charging station  32  includes a plug  44 , or connector, configured to connect to a charging port  46  of the electrified vehicle  12 . Current originating from the external power source  42  may be transferred from the vehicle charging station  32  to the electrified vehicle  12  for charging the battery pack  24  via the charging cord  38 . 
         [0042]    A relatively significant amount of heat may be generated in the battery pack  24  as a result of the charge rates supplied during DC fast charging events and due to the internal resistances of the battery cells of the battery pack  24 . The electrified vehicle  12  is therefore equipped with a thermal management system  50  for managing this heat during charging events. The thermal management system  50  may be a closed-loop cooling system that circulates a coolant C 1  through a portion of the battery pack  24  to remove heat. The coolant C 1  may be any type of coolant, including but not limited to a gas such as air or a liquid such as water mixed with ethylene glycol. The thermal management system  50  may include various conduits or passages  55  for communicating the coolant C 1  to and from the battery pack  24 . 
         [0043]    The thermal management system  50  may have an insufficient capacity to effectively cool the battery pack  24  during DC fast charging events. In such instances, the cooling system  40  of the vehicle charging station  32  can be employed to augment the cooling of the battery pack  24 . In one non-limiting embodiment, the cooling system  40  communicates cooling airflow  48  to a location outside of the housing  34  of the vehicle charging station  32  during DC fast charging events in order to augment the thermal management of the battery pack  24 . 
         [0044]    In one non-limiting embodiment, the cooling system  40  of the vehicle charging station  32  includes a fan  52  and a chiller assembly  54 . A coolant C 2  may be circulated through a heat exchanger  56  of the chiller assembly  54 . The coolant C 2  exchanges heat with an airflow F that is communicated across the heat exchanger  56  by the fan  52 . The airflow F is cooled (i.e., loses heat to the coolant C 2 ) as it is blown across a plurality of fins or coils  58  of the heat exchanger  56  to generate the cooling airflow  48 . The cooling airflow  48  may then be communicated through a vent  60  of the housing  34  toward the electrified vehicle  12  to aid the thermal management system  50  in cooling the battery pack  24 . 
         [0045]    The cooling airflow  48  that is communicated from the vehicle charging station  32  may be directed across a portion of the thermal management system  50  to augment the thermal management of the battery pack  24 . For example, in one non-limiting embodiment, the cooling airflow  48  is directed across a cooling pack  62  of the thermal management system  50 . The cooling pack  62  may include a radiator, a condenser, or both, as well as other components. In one non-limiting embodiment, the cooling pack  62  is mounted near a front end of the electrified vehicle  12  and is in close proximity to the vehicle charging station  32  once the charging cord  38  is plugged into the charging port  46  of the electrified vehicle  12 . 
         [0046]    The cooling airflow  48  picks up heat H from the coolant C 1  that is circulated through the closed loop of the thermal management system  50  as the cooling airflow  48  is communicated across the cooling pack  62 . Stated another way, additional heat H from the coolant C 1  is lost to the cooling airflow  48  as the coolant C 1  is communicated inside the cooling pack  62 . Cooling of the battery pack  24  is therefore augmented by the cooling system  40  of the vehicle charging station  32 . 
         [0047]    The controller  36  of the vehicle charging station  32  is configured to control operation of the cooling system  40  for selectively providing the cooling airflow  48 . In one non-limiting embodiment, the controller  36  may command operation of the cooling system  40  during each DC fast charging event. In another non-limiting embodiment, the controller  36  may command operation of the cooling system  40  each time the charging cord  38  is plugged into a charging port  46  of an electrified vehicle  12 . In yet another non-limiting embodiment, the controller  36  may command continued operation of the cooling system  40  even after a DC fast charging event has ended in order to continue to chill the battery pack  24  during relatively extreme ambient conditions (e.g., when an ambient temperature exceeds a predefined threshold temperature stored in the memory of the controller  36 ). 
         [0048]      FIG. 3  illustrates an exemplary cooling system  40  that could be employed for use within the vehicle charging station  32  described above. The cooling system  40  may include a chiller assembly  54  that includes a compressor  64 , a first heat exchanger  66  (e.g., a condenser), an expansion valve  68 , a second heat exchanger  70  (e.g., an evaporator) and a fan  52 . During operation of the cooling system  40 , the compressor  64  pressurizes and circulates a coolant in a first phase C-1 (i.e., a vapor) through a closed loop  74  of the cooling system  40 . The compressor  64  may be electrically powered using power from the external power source  42  (schematically depicted in  FIG. 2 ). The compressor  64  directs the high pressure coolant to the first heat exchanger  66 . 
         [0049]    The high pressure coolant may next exchange heat with another fluid, such as airflow, within the first heat exchanger  66 . The first heat exchanger  66 , which may be a condenser, transfers heat to the surrounding environment by condensing the coolant from a vapor to a liquid coolant having a second phase C-2. 
         [0050]    The liquid coolant exiting the first heat exchanger  66  may be communicated to the expansion valve  68 , which reduces the pressure of the coolant and results in the evaporation of a portion of the liquid coolant to a combination of a liquid and vapor coolant having a third phase C-3. The temperature of the liquid and vapor coolant mixture is colder than the temperature of the liquid coolant. 
         [0051]    The liquid and vapor coolant mixture exiting the expansion valve  68  is next communicated to the second heat exchanger  70 , which may be configured as an evaporator. Within the second heat exchanger  70 , heat is transferred between the surrounding environment and the liquid and vapor coolant mixture, thereby causing the coolant mixture to completely vaporize. The fan  52  of the cooling system  40  may communicate airflow F across the second heat exchanger  70 , and as this occurs, the airflow F loses heat to the coolant to generate the cooling airflow  48 . 
         [0052]    The cooling system  40  shown and described with reference to  FIGS. 2 and 3  is but one non-limiting embodiment of the type of cooling system that may be employed inside the vehicle charging station  32 . Other cooling system configurations may alternatively or additionally be utilized to direct cooling airflow  48  toward the electrified vehicle  12  during DC fast charging events or during other conditions. 
         [0053]    Although the different non-limiting embodiments are illustrated as having specific components or steps, the embodiments of this disclosure are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments. 
         [0054]    It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings. It should be understood that although a particular component arrangement is disclosed and illustrated in these exemplary embodiments, other arrangements could also benefit from the teachings of this disclosure. 
         [0055]    The foregoing description shall be interpreted as illustrative and not in any limiting sense. A worker of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure. For these reasons, the following claims should be studied to determine the true scope and content of this disclosure.