Claims:1. A battery thermal management system (10) for electric vehicle (200) comprising:
a battery pack (20);
a heat exchanger (50) configured to selectively receive refrigerant from an air conditioning system of the electric vehicle (200);
a valve (80) configured to receive a coolant (40) from the battery pack (20) and selectively redirect the coolant (40) to at least one of the heat exchanger (50), a battery radiator (60) and a heater (70);
a pump (90) configured to pump the coolant (40) through the battery pack (20), the valve (80), the heat exchanger (50), the battery radiator (60) and the heater (70);
characterized by
a monitoring unit (110) comprising a plurality of temperature sensors (120) corresponding to the battery pack (20) and ambient atmosphere, wherein the plurality of temperature sensors (120) is configured to sense temperature reading of the battery pack (20) and the ambient atmosphere;
an electronic control unit (130) configured to:
receive the temperature reading of the battery pack (20) and the ambient atmosphere sensed by the monitoring unit (110);
select a type of heat treatment, from the at least one of the heat exchanger (50), the battery radiator (60) and a heater (70), to be performed on the coolant (40) to maintain an optimum condition of the battery pack,
wherein the pump (90) is configured to pump the coolant induced with a drag reducing polymer from the reservoir (100) depending upon the type of heat treatment selected by the electronic control unit (130), wherein the coolant (40) is pumped across the battery pack (20) with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump (90).
2. The system (10) as claimed in claim 1, wherein the heater (70) is located upstream of the battery pack (20), wherein the heater (70) is configured to receive a flow of the coolant whereby the heater is activated to heat the coolant flowing thereto.
3. The system (10) as claimed in claim 1, wherein the battery radiator (60) is configured to be located adjacent to a cooling fan.
4. The system (10) as claimed in claim 1, wherein the drag reducing polymer comprises one of synthetic polymer or biopolymer.
5. The system (10) as claimed in claim 1, wherein the drag reducing polymer induced coolant is used for uniform heat dissipation across the battery pack (20) in assistance of hybrid cooling medium when used in hybrid battery thermal management system (150).
6. The system (10) as claimed in claim 5, wherein the hybrid cooling medium comprises graphene foam saturated with phase change material.
7. The system (10) as claimed in claim 6, wherein the graphene foam saturated with phase change material are used across surfaces of the battery pack (20) while the coolant (40) in a plurality of cooling pipes (30) mounted across the battery pack are configured to resolve thermal runaway across the battery pack in the electric vehicle.
8. An electric vehicle (200) comprising:
a chassis (210);
a plurality of wheels (220) operatively coupled to the chassis;
a steering (230) operatively coupled to the plurality of wheels;
an electric motor (240) operatively coupled to the plurality of wheels;
a battery thermal management system (10) operatively coupled to the electric motor (240), wherein the battery thermal management system (10) comprises:
a battery pack (20) operatively coupled to the electric motor and configured to drive the electric motor, wherein the battery pack (20) comprises a plurality of battery cells arranged in a plurality of cell arrays;
a heat exchanger (50) configured to selectively receive refrigerant from an air conditioning system of the electric vehicle;
a valve (80) configured to receive a coolant from the battery pack and selectively redirect the liquid coolant to at least one of the heat exchanger (50), a battery radiator (60) and a heater (70);
a pump (90) configured to pump the coolant through the battery pack, the valve, the heat exchanger, the battery radiator and the heater;
characterized by
a monitoring unit (110) comprising a plurality of temperature sensors (120) corresponding to the battery pack and ambient atmosphere, wherein the plurality of temperature sensors (120) is configured to sense temperature reading of the battery pack and the ambient atmosphere;
an electronic control unit (130) configured to:
receive the temperature reading of the battery pack and the ambient atmosphere sensed by the monitoring unit (110);
select a type of heat treatment, from the at least one of the heat exchanger, the battery radiator and a heater, to be performed on the coolant to maintain an optimum condition of the battery pack,
wherein pump (90) is configured to pump the coolant induced with a drag reducing polymer from the reservoir depending upon the type of heat treatment selected by the electronic control unit, wherein coolant (40) is pumped across the battery pack with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump.
9. A method (300) comprising:
sensing, by a monitoring unit, temperature reading of a battery pack and ambient atmosphere using a corresponding plurality of temperature sensors; (310)
receiving, by an electronic control unit, the temperature reading of the battery pack and the ambient atmosphere sensed by the monitoring unit; (320)
selecting, by the electronic control unit, a type of heat treatment, from the at least one of the heat exchanger, the battery radiator and a heater, to be performed on the coolant to maintain an optimum condition of the battery pack; (330) and
pumping, by a pump, the coolant induced with a drag reducing polymer from the reservoir depending upon the type of heat treatment selected by the electronic control unit, wherein coolant is pumped across the battery pack with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump. (340)
Dated this 08th day of July 2021
Signature

Harish Naidu
Patent Agent (IN/PA-2896)
Agent for the Applicant
, Description:FIELD OF INVENTION
[0001] Embodiments of the present disclosure relate to thermal systems for battery packs in vehicles, and more particularly to a battery thermal management system for electric vehicles and a method to operate the same.
BACKGROUND
[0002] As problem of environmental pollution becomes increasingly conspicuous, new-energy automobile develops very rapid in recent years. Advanced automotive vehicles are being introduced that employ a battery pack to store large amounts of energy for electric propulsion systems. Power battery using lithium ion battery as representative has been widely used for providing power for new-energy automobile. Industry at present believe that the more excellent environment temperature of lithium ion battery work is 20~40 DEG C, the lithium ion to work in this temperature range is dynamic on boundary power battery is able to maintain very high efficiency for charge-discharge and realizes longer service life. Existing power battery cooling system are mostly air-cooled, or liquid-cooling system which dissipate heat in battery. However, when vehicle is travelled at a relatively high speed, electrokinetic cell may produce substantial amount of heat, and liquid cooling system or air cooling system do not reach to cooling requirement sometimes.
[0003] Presently used liquid cooling system in the battery packs needs high power pumps to run the fluid inside the cooling tubes inside the pack. However, such system consumes high power from the battery pack due to the pumps used in pumping the cooling fluid across the battery packs.
[0004] Hence, there is a need for an improved battery thermal management system for electric vehicles and a method to operate the same to address the aforementioned issue(s).

BRIEF DESCRIPTION
[0005] In accordance with an embodiment of the present disclosure, a battery thermal management system for electric vehicle is provided. The system includes a battery pack. The system also includes a heat exchanger configured to selectively receive refrigerant from an air conditioning system of the electric vehicle. The system includes a battery radiator configured to be located adjacent to a cooling fan. The system further includes a valve configured to receive a coolant from the battery pack and selectively redirect the liquid coolant to at least one of the heat exchanger, the battery radiator and a heater. The system further includes a pump configured to pump the coolant through the battery pack, the valve, the heat exchanger, the battery radiator and the heater. The system further includes a monitoring unit comprising a plurality of temperature sensors corresponding to the battery pack and ambient atmosphere. The plurality of temperature sensors is configured to sense temperature reading of the battery pack and the ambient atmosphere. The system further includes an electronic control unit configured to receive the temperature reading of the battery pack and the ambient atmosphere sensed by the monitoring unit. The electronic control unit is also configured to select a type of heat treatment, from the at least one of the heat exchanger, the battery radiator and a heater, to be performed on the coolant to maintain an optimum condition of the battery pack. The pump is configured to pump the coolant induced with a drag reducing polymer from the reservoir depending upon the type of heat treatment selected by the electronic control unit, where the coolant is pumped across the battery pack with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump.
[0006] In accordance with yet another embodiment of the present disclosure, an electric vehicle with battery management system is provided. The vehicle includes a chassis and a plurality of wheels operatively coupled to the chassis. The vehicle includes a steering operatively coupled to the plurality of wheels and an electric motor operatively coupled to the plurality of wheels. The vehicle also includes a battery thermal management system operatively coupled to the electric motor. The battery thermal management system includes a battery pack operatively coupled to the electric motor and configured to drive the electric motor. The battery pack comprises a plurality of battery cells arranged in a plurality of cell arrays. The battery thermal management system includes a heat exchanger configured to selectively receive refrigerant from an air conditioning system of the electric vehicle. The battery thermal management system includes a battery radiator configured to be located adjacent to a cooling fan. The battery thermal management system includes a valve configured to receive a coolant from the battery pack and selectively redirect the liquid coolant to at least one of the heat exchanger, the battery radiator and a heater. The battery thermal management system includes a pump configured to pump the coolant through the battery pack, the valve, the heat exchanger, the battery radiator and the heater. The system further includes a monitoring unit comprising a plurality of temperature sensors corresponding to the battery pack and ambient atmosphere. The plurality of temperature sensors is configured to sense temperature reading of the battery pack and the ambient atmosphere. The system further includes an electronic control unit configured to receive the temperature reading of the battery pack and the ambient atmosphere sensed by the monitoring unit. The electronic control unit is also configured to select a type of heat treatment, from the at least one of the heat exchanger, the battery radiator and a heater, to be performed on the coolant to maintain an optimum condition of the battery pack. The pump is configured to pump the coolant induced with a drag reducing polymer from the reservoir depending upon the type of heat treatment selected by the electronic control unit, where the coolant is pumped across the battery pack with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump.
[0007] In accordance with yet another embodiment of the present disclosure, a method to operate the battery management system is provided. The method includes sensing, by a monitoring unit, temperature reading of a battery pack and ambient atmosphere using a corresponding plurality of temperature sensors. The method also includes receiving, by an electronic control unit, the temperature reading of the battery pack and the ambient atmosphere sensed by the monitoring unit. The method further includes selecting, by the electronic control unit, a type of heat treatment, from the at least one of the heat exchanger, the battery radiator and a heater, to be performed on the coolant to maintain an optimum condition of the battery pack. The method further includes pumping, by a pump, the coolant induced with a drag reducing polymer from the reservoir depending upon the type of heat treatment selected by the electronic control unit, wherein coolant is pumped across the battery pack with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump.
[0008] To further clarify the advantages and features of the present invention, a more particular description of the invention will follow by reference to specific embodiments thereof, which are illustrated in the appended figures. It is to be appreciated that these figures depict only typical embodiments of the invention and are therefore not to be considered limiting in scope. The invention will be described and explained with additional specificity and detail with the appended figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The disclosure will be described and explained with additional specificity and detail with the accompanying figures in which:
[00010] FIG. 1 is a schematic representation of a battery thermal management system in accordance with an embodiment of the present disclosure;
[00011] FIG. 2 is a block diagram representation of flow of treated fluid inside the battery pack in accordance with an embodiment of the present disclosure;
[00012] FIG. 3 is a schematic represent of the battery thermal management system of FIG. 1, depicting drag reducing polymers induced liquid cooling system in accordance with an embodiment of the present disclosure;
[00013] FIG. 4 is a block diagram of one embodiment of the battery thermal management system of FIG. 1 and 3, depicting hybrid battery thermal management system in accordance with an embodiment of the present disclosure;
[00014] FIG. 5 is a schematic representation of another embodiment of the battery thermal management system of FIG. 1 and FIG. 3, depicting a vehicle having the battery thermal management system in accordance with an embodiment of the present disclosure; and
[00015] FIG. 6 is a flow chart representing the steps involved in a method for operating the battery thermal management system in accordance with an embodiment of the present disclosure.
[00016] Further, those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the figures by conventional symbols, and the figures may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the figures with details that will be readily apparent to those skilled in the art having the benefit of the description herein.
DETAILED DESCRIPTION
[00017] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the figures and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as would normally occur to those skilled in the art are to be construed as being within the scope of the present invention.
[00018] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.
[00019] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such a process or method. Similarly, one or more devices or sub-systems or elements or structures or components preceded by "comprises... a" does not, without more constraints, preclude the existence of other devices, sub-systems, elements, structures, components, additional devices, additional sub-systems, additional elements, additional structures or additional components. Appearances of the phrase "in an embodiment", "in another embodiment" and similar language throughout this specification may, but not necessarily do, all refer to the same embodiment.
[00020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs. The system, methods, and examples provided herein are only illustrative and not intended to be limiting.
[00021] Embodiments of the present disclosure will be described below in detail with reference to the accompanying figures.
[00022] In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings. The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.
[00023] Embodiments of the present disclosure relate to a battery thermal management system. The system includes a battery pack. The system also includes a heat exchanger configured to selectively receive refrigerant from an air conditioning system of the electric vehicle. The system includes a battery radiator configured to be located adjacent to a cooling fan. The system further includes a valve configured to receive a coolant from the battery pack and selectively redirect the liquid coolant to at least one of the heat exchanger, the battery radiator and a heater. The system further includes a pump configured to pump the coolant through the battery pack, the valve, the heat exchanger, the battery radiator and the heater. The system further includes a monitoring unit comprising a plurality of temperature sensors corresponding to the battery pack and ambient atmosphere. The plurality of temperature sensors is configured to sense temperature reading of the battery pack and the ambient atmosphere. The system further includes an electronic control unit configured to receive the temperature reading of the battery pack and the ambient atmosphere sensed by the monitoring unit. The electronic control unit is also configured to select a type of heat treatment, from the at least one of the heat exchanger, the battery radiator and a heater, to be performed on the coolant to maintain an optimum condition of the battery pack. The pump is configured to pump the coolant induced with a drag reducing polymer from the reservoir depending upon the type of heat treatment selected by the electronic control unit, where the coolant is pumped across the battery pack with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump.
[00024] FIG. 1 is a schematic representation of a battery thermal management system (10) in accordance with an embodiment of the present disclosure. The battery management system (BMS) is an electronic system which manages a rechargeable battery (cell or battery pack), such as by protecting the battery from operating outside its safe operating area, monitoring its state, calculating secondary data, reporting that data, controlling its environment, authenticating and/or balancing the battery. The battery management system is configured to monitor voltage, current, temperature of the battery pack, coolant flow and manage thermal management of the battery pack. The system (10) includes a battery pack (20). As used herein, the battery pack includes a set of identical batteries or individual battery cells. The set of battery cells may be configured in a series, parallel or a mixture of both to deliver the desired voltage, capacity, or power density. The battery pack (20) includes a set of interconnects (not shown in FIG. 1) which provide electrical conductivity between the set of battery cells. In one embodiment, the battery pack may be a rechargeable battery pack. The rechargeable battery packs often contain a temperature sensor, which the battery charger uses to detect the end of charging. The set of interconnects are also found in batteries as they are the part which connects each cell, though batteries are most often only arranged in series strings.
[00025] Furthermore, the battery pack (20) includes a plurality of pipes (30) inside the battery pack for thermal management as shown in FIG. 2. The plurality of pipes (30) is configured to pass the coolant (40) inside the battery pack. In one embodiment, the coolant (40) may include at least one of air, liquid, or some form of phase change. In a specific embodiment, the plurality of pipes (30) may be arranged in at least one of a linear arrangement, hexagonal arrangement, serpentine arrangement or the like depending upon the size and type of the battery pack. In such an embodiment, the battery pack (20) may include cylindrical batteries, prismatic batteries or the like.
[00026] Referring back to FIG. 1, the system (10) also includes a heat exchanger (50) which is configured to selectively receive refrigerant from an air conditioning system of the electric vehicle. The system (10) further includes a battery radiator (60) which is configured to be located adjacent to a cooling fan. In one embodiment, the battery radiator (60) may be mounted adjacent to the radiator so that air flow that is drawn through the radiator by the cooling fan will also be drawn through the battery radiator. The heat exchanger (50) is connected, via refrigerant lines, to the air conditioning system. In some embodiments, the system (10) includes a heater (70) which is located upstream of the battery pack (20). The heater (70) is configured to receive a flow of the coolant whereby the heater is activated to heat the coolant flowing thereto. The heater (70), heat exchanger (50) and the battery radiator (60) are connected in parallel to each other via a valve (80). The valve (80) is configured to receive the coolant (40) from the battery pack (20) and selectively redirect the coolant (40) to at least one of the heat exchanger (50), the battery radiator (60) and the heater (70). In one embodiment, the valve (80) may be a four way valve.
[00027] More specifically, the valve (80) is connected to coolant pipes (30) and is controllable to selectively direct a flow of coolant from the battery pack (20) to either the heat exchanger (50), heater (70) or the battery radiator (60). As used herein, coolant is a substance, typically liquid or gas, which is used to reduce or regulate the temperature of a system. An ideal coolant has high thermal capacity, low viscosity, is low-cost, non-toxic, chemically inert and neither causes nor promotes corrosion of the cooling system. In one embodiment, the coolant (40) may be a common coolant such as a water and ethylene glycol mix. The system may use a specialized coolant using de-ionized water and/or special inhibitors or may be some other type of liquid coolant with suitable heat transfer properties.
[00028] The system (10) further includes a pump (90) which is configured to pump the coolant (40) through the battery pack (20), the valve (80), the heat exchanger (50), the battery radiator (60) and the heater (70). The pump (90) is coupled to a reservoir (100) which is having a low pressure cap and is connected to an air separator and allows for thermal expansion and contraction of the coolant in the battery thermal system. The battery thermal system (10) may be operated in three modes. The first mode is a battery cooling mode where the air conditioning system is not operating, thus no refrigerant flow through the heat exchanger (50). The first mode employs battery radiator (60) cooling and is most strategically employed when the ambient air temperature is not too warm, and the electric vehicle operator has not turned on the air conditioning system. The first mode may be employed while operating the electric vehicle and while the electric vehicle is plugged-in for battery recharging. The second mode is a battery cooling mode where the air conditioning system is operating. The pump (90) is activated, and the valve (80) is actuated to direct the coolant coming from the battery pack (20) to the heat exchanger (bypassing the battery radiator). The coolant (40) flowing through the battery pack absorbs heat and then flows through the coolant lines to the heat exchanger. The second mode may be employed while operating the electric vehicle and while the electric vehicle is plugged-in for battery recharging if the air conditioning system may be operated on electric power. The third mode is a battery heating mode where there are cold ambient conditions. The pump (90) is activated, and the valve (80) is actuated to direct the coolant coming from the battery pack to the heat exchanger (bypassing the battery radiator). In this mode, no cooled refrigerant flows through the heat exchanger, no heat transfer takes place. The heater (70) is activated and transfers heat to the coolant as it passes through. The heat is then transferred to the battery pack (20) as the coolant flows through it, thus warming the battery pack. This mode may also be employed while operating the electric vehicle or while the electric vehicle is plugged-in for battery recharging.
[00029] FIG. 3 is a schematic represent of the battery thermal management system (10) of FIG. 1, depicting drag reducing polymers induced liquid cooling system in accordance with an embodiment of the present disclosure. The system (10) includes a monitoring unit (110) which includes a plurality of temperature sensors (120) corresponding to the battery pack (20) and ambient atmosphere. The plurality of temperature sensors (120) is configured to sense temperature reading of the battery pack and the ambient atmosphere. In one embodiment, the NTC thermistor sensors obtain the necessary temperature readings from direct contact with the battery cell body. Alternatively, temperature sensors are installed on the cell's electrical terminals to obtain the cell temperature. In another embodiment, the plurality of temperature sensors (120) is located underneath the battery box and is placed directly below the battery. Most batteries develop excessive heat towards the bottom of the core and often in the middle of the battery, which is why the temperature sensor is located in this position.
[00030] In addition, the system (10) includes an electronic control unit (130) operatively coupled to the monitoring unit (110). The electronic control unit (130) is configured to receive the temperature reading of the battery pack (20) and the ambient atmosphere sensed by the monitoring unit (110). The electronic control unit (130) is also configured to select a type of heat treatment, from the at least one of the heat exchanger (50), the battery radiator (60) and a heater (70), to be performed on the coolant (40) to maintain an optimum condition of the battery pack (20). The pump (90) is configured to pump the coolant induced with a drag reducing polymer from the reservoir (100) depending upon the type of heat treatment selected by the electronic control unit (130). As used herein, drag-reducing polymers (DRP's) are additives in pipelines which reduce turbulent disturbances in the inner surface of a pipe. Using few parts per million of DRP’s, leads to a high-percentage of drag reduction which enhances the pipeline capacity, resulting substantial amount of cost and energy savings. When the polymer is added, the polymer interacts with the coolant and the wall to help reduce the contact of the coolant with the wall. In one embodiment, the drag reducing polymer may be one of synthetic polymer or biopolymer. The coolant (40) induced with the drag reducing polymer is pumped across the battery pack (20) with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump.
[00031] FIG. 4 is a block diagram of one embodiment of the battery thermal management system (10) of FIG. 1 and 3, depicting hybrid battery thermal management system (150) in accordance with an embodiment of the present disclosure. In case of any application in hybrid battery thermal management system (150), the DRP induced liquid cooling system may be used in uniform heat dissipation across the battery pack (20) in assistance of any hybrid cooling medium. The system (10) may be most efficient when used in hybrid combination of graphene induced phase change material (PCM) media (160) and DRP induced liquid cooling system. As used herein, the phase change materials are substances that absorb and release thermal energy (heat) during the process of melting and freezing. They are called “phase change” materials because they go from a solid to a liquid state or vice versa during the thermal cycling process. In detail, the graphene foam saturated with phase change material are used across the surfaces of the battery packs while the liquid cooling system in the cooling pipes mounted across the battery pack would resolve the major issue of thermal runaway across the battery pack in the electric vehicle.
[00032] FIG. 5 is a schematic representation of another embodiment of the battery thermal management system (10) of FIG. 1 and FIG. 3, depicting an electric vehicle (200) having the battery thermal management system (10) in accordance with an embodiment of the present disclosure. The vehicle (200) includes a chassis (210) and a plurality of wheels (220) operatively coupled to the chassis. The vehicle (200) includes a steering (230) operatively coupled to the plurality of wheels and an electric motor (240) operatively coupled to the plurality of wheels. The vehicle (200) further includes an engine compartment (250) within which a power plant (262) is mounted. In one embodiment, the vehicle (200) also includes a passenger cabin area (260), within which a battery pack (20) is mounted. In another embodiment, the battery pack may be mounted outside of the passenger cabin area. The battery pack may include a plug-in charger (261). The power plant may have coolant lines (30) which may be located adjacent to a cooling fan (265).
[00033] The vehicle (200) also includes a battery thermal management system (10) operatively coupled to the electric motor (240). The battery thermal management system includes the battery pack (20) operatively coupled to the electric motor (240) and configured to drive the electric motor (240). The battery pack (20) comprises a plurality of battery cells arranged in a plurality of cell arrays. The battery thermal management system includes a heat exchanger (50) configured to selectively receive refrigerant from an air conditioning system of the electric vehicle (200). The battery thermal management system includes a battery radiator (60) configured to be located adjacent to a cooling fan. The battery thermal management system includes a heater (70) which is located upstream of the battery pack. The heater (70) is configured to receive a flow of the coolant (40) whereby the heater is activated to heat the coolant flowing thereto.
[00034] The battery thermal management system (10) includes a valve (80) configured to receive the coolant (40) from the battery pack and selectively redirect the liquid coolant to at least one of the heat exchanger (50), the battery radiator (60) and a heater (70). The battery thermal management system includes a pump (90) configured to pump the coolant through the battery pack (20), the valve (80), the heat exchanger (50), the battery radiator (60) and the heater (70). The system further includes a monitoring unit (110) comprising a plurality of temperature sensors (120) corresponding to the battery pack and ambient atmosphere. The plurality of temperature sensors (120) is configured to sense temperature reading of the battery pack and the ambient atmosphere. The system further includes an electronic control unit (130) configured to receive the temperature reading of the battery pack and the ambient atmosphere sensed by the monitoring unit. The electronic control unit (130) is also configured to select a type of heat treatment, from the at least one of the heat exchanger, the battery radiator and a heater, to be performed on the coolant to maintain an optimum condition of the battery pack. The pump (90) is configured to pump the coolant induced with a drag reducing polymer from the reservoir depending upon the type of heat treatment selected by the electronic control unit, where the coolant is pumped across the battery pack with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump.
[00035] FIG. 6 is a flow chart representing the steps involved in a method (300) for operating the battery thermal management system in accordance with an embodiment of the present disclosure. The method (300) includes sensing, by a monitoring unit, temperature reading of a battery pack and ambient atmosphere using a corresponding plurality of temperature sensors in step 310. The method (300) also includes receiving, by an electronic control unit, the temperature reading of the battery pack and the ambient atmosphere sensed by the monitoring unit in step 320. The method (300) further includes selecting, by the electronic control unit, a type of heat treatment, from the at least one of the heat exchanger, the battery radiator and a heater, to be performed on the coolant to maintain an optimum condition of the battery pack in step 330.
[00036] The method (300) further includes pumping, by a pump, the coolant induced with a drag reducing polymer from the reservoir depending upon the type of heat treatment selected by the electronic control unit, where coolant is pumped across the battery pack with minimal effect on fluid characteristics of the coolant, thereby reducing power consumption or operational time of the pump in step 340. In one embodiment, the drag reducing polymer may be one of synthetic polymer or biopolymer. In a specific embodiment, the drag reducing polymer induced coolant is used for uniform heat dissipation across the battery pack in assistance of hybrid cooling medium when used in hybrid battery thermal management system. In such an embodiment, the hybrid cooling medium may include graphene foam saturated with phase change material. In some embodiment, the graphene foam saturated with phase change material are used across surfaces of the battery packs while the coolant in one or more cooling pipes mounted across the battery pack are configured to resolve thermal runaway across the battery pack in the electric vehicle.
[00037] Various embodiments of the battery thermal management system described above enables efficient thermal management system with minimum power consumption and may also avoid thermal runaway problem existing in the conventional systems using the drag reducing polymers. With use of high molecular weight drag-reducing polymers (DRP’s) (synthetic/biopolymers) the skin friction force can be reduced, that would reduce the operational time of the pump while circulating the cooling fluid across the battery packs. The system may also be incorporated with any hybrid battery management system having liquid cooling system as a primary system resolving the issues of uniform heat dissipation/thermal runaway. Another advantage of an embodiment is that the battery thermal system provides battery cooling whether the vehicle air conditioning system is off or on. The system saves electric energy, improves the endurance of new-energy automobile, and is also safe. The use of phase change material improves the security of battery system.
[00038] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the disclosure and are not intended to be restrictive thereof. While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended.
[00039] The figures and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, the order of processes described herein may be changed and are not limited to the manner described herein. Moreover, the actions of any flow diagram need not be implemented in the order shown; nor do all of the acts need to be necessarily performed. Also, those acts that are not dependent on other acts may be performed in parallel with the other acts. The scope of embodiments is by no means limited by these specific examples.