Claims:WE CLAIM:

1. A Battery system (100), comprising:
an outer casing comprising a left side wall (103), a right side wall (104), a top wall (105), a bottom wall (106), a front wall (101), and a back wall (102) coupled to each other for providing structural support to the battery system (100), wherein, the side walls (103) and (104) further comprise channels (121) and (122);
a thermal insulation provided on to the outside walls of the casing (102), (104), (101), (103), (105), and (106);
inlet gates (111) and (112), and outlet gates (113) and (114) hinged to the side walls (103) and (104), wherein, the inlet and outlet gates (111), (112), (113), and (114) contain a material which is attracted or repelled by a magnet;
at least one electromagnet (151) to (158) for each inlet and outlet gate (111), (112), (113), and (114) coupled to the front wall (101), back wall (102) or side walls (103) and (104), wherein the said electromagnets (151) to (158) attract or release the gates (111), (112), (113), and (114), thereby closing and opening operation of the gate controls air flow through the channels (121) and (122);
at least one battery module (130) arranged inside the outer casing, comprising at least one battery cell (134);
at least one supporting structure (131), configured for providing structural support to the at least one battery cell (134);
at least one pump (170) to generate pressure head and thus maintain required flow rate of the liquid coolant through liquid channels;
at least one heating element (140) present inside the liquid channel to heat up the flowing liquid when required;
wherein, during hot climate condition, the electromagnets (151) to (158) open the inlet and outlet gates (111), (112), (113), and (114) such that upstream air flowing around the battery system enters the outer channels (121) and (122), the pump (170) generates pressure head and thus maintain required flow rate of the liquid coolant through liquid channels such that, the heat produced during operation of the battery cells (134) is absorbed by the liquid and is discharged to the inner chambers (161) and (162) thereby maintaining desired operating temperature of the battery cell (134), and the heat absorbed by the inner chambers (161) and (162) is further transferred to the outer channels (121) and (122), and the air flowing through the channels (121) and (122) further absorbs the heat and discharges the heat to the environment;
wherein, during a cold climate condition, the electromagnets (151) to (158) close the inlet and outlet gates (111), (112), (113), and (114) such that upstream air flowing around the vehicle passes around the battery system (100) without entering the outer channels (121) and (122), the heating element (140) is turned on, the pump (170) generates pressure head and thus maintain required flow rate of the liquid through liquid channels such that, the heat produced by the heating element (140) is absorbed by the flowing liquid and is discharged to the battery cells (134), thereby heating up the battery cells (134) to desired operating temperature;
wherein, the operation of one or more electromagnets (151) to (158), one or more pumps (170), and one or more heating elements (140) is controlled and monitored by one or more controllers.

2. An Electric Vehicle system (600), comprising:
a chassis (610) configured to provide structure to the electric vehicle;
at least one controller (620) operatively coupled within the chassis (610), and configured to control a plurality of electronic components within the electric vehicle, wherein the one or more controllers (620) are operatively coupled to one or more sensors, thereby detecting the ambient air temperature and the battery cell temperature;
a battery system (100) placed within the chassis (610) and is operatively coupled to at least one controller (620), wherein the battery system (100) comprises
an outer casing comprising a left side wall (103), a right side wall (104), a top wall (105), a bottom wall (106), a front wall (101), and a back wall (102) coupled to each other for providing structural support to the battery system (100), wherein, the side walls (103) and (104) further comprise channels (121) and (122);
a thermal insulation provided on to the outside walls (102), (104), (101), (103), (105), and (106);
inlet gates (111) and (112), and outlets gates (114) and (113) hinged to the side walls (103) and (104), wherein, the inlet and outlet gates (111), (112), (113), and (114) contain a material which can be attracted or repelled by a magnet;
at least one electromagnet (151) to (158) for each inlet and outlet gates (111), (112), (113), and (114) coupled to the front wall (101), back wall (102) or side walls (103) and (104), wherein the said electromagnets (151) to (158) attract or release the gates (111), (112), (113), and (114), thereby closing and opening operation of the gate controls air flow through the channels (121) and (122);
at least one battery module (130) arranged inside the outer casing, comprising at least one battery cell (134);
at least one supporting structure (131), configured for providing structural support to the at least one battery cell (134);
at least one pump (170) to generate pressure head and thus maintain required flow rate of the liquid through liquid channels;
at least one heating element (140) present inside the liquid channel to heat up the flowing liquid when required;
wherein, in hot climate condition, the electromagnets (151) to (158) open the inlet and outlet gates (111), (112), (113), and (114) such that upstream air flowing around the battery system enters the outer channels (121) and (122), the pump (170) generate pressure head and thus maintain required flow rate of the liquid coolant through liquid channels such that, the heat produced during operation of the battery cells (134) is absorbed by the liquid and is discharged to the inner chambers (161) and (162) thereby maintaining desired operating temperature of the battery cell (134), and the heat absorbed by the inner chambers (161) and (162) is further transferred to the outer channels (121) and (122), and the air flowing through the channels (121) and (122) further absorbs the heat and discharges the heat to the environment;
wherein, in a cold climate condition, the electromagnets (151) to (158) close the inlet and outlet gates (111), (112), (113), and (114) such that upstream air flowing around the vehicle passes around the battery system (100) without entering the outer channels (121) and (122), the heating element (140) is turned on, the pump (170) generate pressure head and thus maintain required flow rate of the liquid through liquid channels such that, the heat produced by the heating element (140) is absorbed by the flowing liquid and is discharged to the battery cells (134), thereby heating up the battery cells (134) to desired operating temperature;
wherein, the operation of one or more electromagnets (151) to (158), one or more pumps (170), and one or more heating elements (140) is controlled and monitored by the said one or more controllers (620).

3. The Battery system (100) as claimed in claim 1, wherein one or more pumps (170) operate in a bidirectional manner, thereby providing a to and fro flow of liquid through liquid channels to maintain equal operating temperatures of the battery cells (134) in a module (130).

4. The Battery system (100) as claimed in claim 1,wherein the battery system (100) comprise:
at least one liquid reservoir (420) configured to provide storage of the liquid, wherein the reservoir has a filler cap (421) to allow liquid filling in the battery pack system (100);
at least one mechanical pressure relief valve (410), configured to provide safe return of liquid vapours into the liquid reservoir;

5. The Battery system (100) as claimed in claim 1,wherein the battery system (100) comprise:
at least one liquid reservoir (420) configured to provide storage of the liquid, wherein the reservoir has a filler cap (421) to allow liquid filling in the battery pack system (100); and
at least one electronic pressure relief valve (410), configured to provide safe return of liquid vapours into the liquid reservoir;
wherein, the operation of one or more electronic pressure relief valve (410) is controlled and monitored by one or more controllers.

6. The Battery system (100) as claimed in claim 1, wherein the inner chamber comprises fin structures (163) for enhanced heat transfer between the liquid coolant and inner chamber.

7. The Battery system (100) as claimed in claim 1, wherein the one or more battery cells (134) are arranged in an inline manner inside the battery module (130).

8. The Battery system (100) as claimed in claim 1, wherein the one or more battery cells (134) are arranged in a staggered manner inside the battery module (130).

9. The Battery system (100) as claimed in claim 1, wherein the outer casing walls (101) to (106) are made up of thermally insulating material, thereby eliminating the need of thermal insulation on the outside.

10. The Battery system (100) as claimed in claim 1, wherein the outer channels (121) and (122) further comprise fins, thereby increasing the heat transfer to the outside air.

11. The Electric Vehicle system (600) as claimed in claim 2, wherein the one or more controller (620) is operatively coupled within the battery pack system (100).
, Description:
FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)

“BATTERY SYSTEM WITH ACTIVE TEMPERATURE MANAGEMENT”
By
Emflux Motors Pvt. Ltd.
An Indian Company
No. 16, Bhuvanappa Layout, Tavarekere Main Road, Kaveri Layout, Suddagunte Palya, Bengaluru, Karnataka 560029

The following specification particularly describes the invention and the manner in which it is to be performed.

FIELD OF INVENTION

[001] The present invention relates generally to the field of battery operated electric vehicles and specifically relates to system and methods for temperature regulations in battery pack system comprising a plurality of battery cells.

BACKGROUND

[002] A battery pack system includes multiple modules comprising plurality of battery cells. Battery pack systems are widely used in vehicles. Vehicles using electric power for all or a portion of their motive power (e.g., Battery electric vehicles (BEVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and the like, collectively referred to as “electric vehicles”), may provide a number of advantages as compared to more traditional gas-powered vehicles using internal combustion engines. Over the rising concerns of oil costs, climate change and energy security, efforts to promote energy efficient electric vehicles have grown. Energy efficient electric vehicles provide overall reduced air emissions compared to conventional combustion vehicles.

[003] The performance of electric vehicles depend on a battery pack system. It is known that temperature has an influence over life and safety of a battery pack system. For electric vehicle applications, a battery pack system experiences high charge and discharge rates and the internal chemical reactions of the battery cell generates heat.

[004] The battery pack system needs to be charged and discharged at a suitable temperature range to minimize the battery cell life degradation. Thus, a thermal management system for a battery pack system is required to keep the battery cell temperature within an optimum range to achieve desired performance in varied climate conditions before and during charging as well as discharging the battery pack system.

[005] Battery pack systems incorporated with liquid cooling thermal management system comprises radiators or external heat exchangers. Thus, the coolant flows through the battery system and gets cooled at the radiator or heat exchanger. Such systems are complex and occupy more space in applications where size is a constraint.

[006] Present invention provides a compact battery pack system for actively maintaining the operating temperature of the battery cells.

SUMMARY

[007] This summary is provided to introduce a selection of concepts in a simple manner that is further described in the detailed description of the disclosure. This summary is not intended to identify key or essential inventive concepts of the subject matter nor is it intended for determining the scope of the disclosure.

[008] In one embodiment, a battery pack system is disclosed. The battery pack system comprises an outer casing, further comprising a left side wall, a right side wall, a top wall, a bottom wall, a front wall, and a back wall attached to each other for providing structural support to the battery system. The side walls further comprise channels for air to flow through them. A thermal insulation is provided on to the outside walls, thereby thermally insulating the battery pack with the environment. Inlet gates and outlets gates are provided and are hinged to the side walls wherein, the inlet and outlet gates contain a material which can be attracted or repelled by a magnet. At least one electromagnet for each inlet and outlet gate attached to the casing, wherein the said electromagnets attract or release the gates, thereby closing and opening operation of the gate controls air flow through the channels. At least one battery module arranged inside the outer casing, comprising at least one battery cell. At least one supporting structure, configured for providing structural support to the at least one battery cell. At least one pump to generate pressure head and thus maintain required flow rate of the liquid coolant through liquid channels. At least one heating element present inside the battery system to heat up the flowing liquid when required. In hot climate, the electromagnets open the inlet and outlet gates such that upstream air flowing around the vehicle enters the outer channels, the pump generates pressure head and thus maintain required flow rate of the liquid coolant through liquid channels such that, the heat produced during operation of the battery cells is absorbed by the liquid and is discharged to the inner chambers thereby maintaining desired operating temperature of the battery cell, and the heat absorbed by the inner chambers is further transferred to the outer channels, and the air flowing through the channels further absorbs the heat and discharges the heat to the environment. In cold climates, the electromagnets close the inlet and outlet gates such that upstream air flowing around the vehicle does not enter the outer channels, the heating element is turned on, the pump generates pressure head and thus maintain required flow rate of the liquid through liquid channels such that, the heat produced by the heating element is absorbed by the flowing liquid, thereby heating up the battery cells to a desired operating temperature. The operation of one or more electromagnets, one or more pumps, and one or more heating elements is controlled and monitored by one or more controllers placed suitably externally or internally of the battery pack system.

[009] Another embodiment of the present invention discloses an Electric Vehicle. The electric vehicle includes a chassis. The chassis is configured to provide a structure to the electric vehicle. The electric vehicle also includes at least one controller operatively coupled within the chassis or within battery system. The at least one controller is configured to control a plurality of electronic components within the electric vehicle, wherein the one or more controllers are operatively coupled to sensors, thereby detecting the ambient air temperature and the battery cell temperature. The electric vehicle system also includes a battery system placed within the chassis and is operatively coupled to the at least one controller. The battery pack system comprises an outer casing, further comprising a left side wall, a right side wall, a top wall, a bottom wall, a front wall, and a back wall attached to each other for providing structural support to the battery system. The side walls further comprise channels for air to flow through them. A thermal insulation is provided on to the outside walls, thereby thermally insulating the battery pack with the environment. Inlet gates and outlets gates are provided and are hinged to the side walls wherein, the inlet and outlet gates contain a material which can be attracted or repelled by a magnet. At least one electromagnet for each inlet and outlet gate attached to the casing, wherein the said electromagnets attract or release the gates, thereby closing and opening operation of the gate controls air flow through the channels. At least one battery module arranged inside the outer casing, comprising at least one battery cell. At least one supporting structure, configured for providing structural support to the at least one battery cell. At least one pump to generate pressure head and thus maintain required flow rate of the liquid coolant through liquid channels. At least one heating element present inside the battery system to heat up the flowing liquid when required. In hot climate, the electromagnets open the inlet and outlet gates such that upstream air flowing around the vehicle enters the outer channels, the pump generates pressure head and thus maintain required flow rate of the liquid coolant through liquid channels such that, the heat produced during operation of the battery cells is absorbed by the liquid and is discharged to the inner chambers thereby maintaining desired operating temperature of the battery cell, and the heat absorbed by the inner chambers is further transferred to the outer channels, and the air flowing through the channels further absorbs the heat and discharges the heat to the environment. In cold climates, the electromagnets close the inlet and outlet gates such that upstream air flowing around the vehicle does not enter the outer channels, the heating element is turned on, the pump generates pressure head and thus maintain required flow rate of the liquid through liquid channels such that, the heat produced by the heating element is absorbed by the flowing liquid, thereby heating up the battery cells to a desired operating temperature. The operation of one or more electromagnets, one or more pumps, and one or more heating elements is controlled and monitored by one or more controllers placed suitably externally or internally of the battery pack system.

[0010] Furthermore, different embodiments of the present invention describe the use of combination of above stated structures and devices for maintaining respective operating temperatures of the battery cells inside the battery pack system and overall electric vehicle.

[0011] The summary above is illustrative only and is not intended to be in any way limiting. Further aspects, exemplary embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF DRAWINGS

[0012] Embodiments of the disclosure will now be described, by way of example, with reference to the accompanying drawings, in which:

[0013] FIG. 1a is a perspective view of the battery pack system, in accordance with a first embodiment of the present invention.

[0014] FIG. 1b is a perspective view of the battery module, in accordance with the first embodiment of the present invention.

[0015] FIG. 1c is a perspective view of the battery module excluding liquid channel and the structure supporting it, in accordance with the first embodiment of the present invention.

[0016] FIG. 1d is a section perspective view of the battery module excluding liquid channel and the structure supporting it, in accordance with the first embodiment of the present invention.

[0017] FIG. 1e is a perspective view of the assembly of battery modules and some parts of cooling structure, in accordance with the first embodiment of the present invention.

[0018] FIG. 1f is a section perspective view of the battery pack system emphasizing module assembly inside the battery pack , in accordance with the first embodiment of the present invention.

[0019] FIG. 1g is a section perspective view of the outer casing and some part of the cooling structure of the battery pack system, in accordance with the first embodiment of the present invention.

[0020] FIG. 1h is a top section view of the outer casing of the battery pack system, in accordance with the first embodiment of the present invention.

[0021] FIG. 2a is a top section view of battery cell arrangement inside the battery module emphasizing inline arrangement of battery cells and flow of liquid coolant, in accordance with a second embodiment of the present invention.

[0022] FIG. 2b is a top section view of battery cell arrangement inside the battery module emphasizing staggered arrangement of battery cells and flow of liquid coolant, in accordance with a third embodiment of the present invention.

[0023] FIG. 3a is a bottom section view of the battery pack system emphasizing external air flow and internal liquid flow, in accordance with a fourth embodiment of the present invention.

[0024] FIG. 3b is a bottom section view of the battery pack system emphasizing internal liquid flow, in accordance with a fifth embodiment of the present invention.

[0025] FIG. 4 is a side section view of the battery pack system with an additional liquid reservoir attached with pressure relief valve, in accordance with a sixth embodiment of the present invention.

[0026] FIG. 5 is a section perspective view of the outer casing of the battery pack system emphasizing fin structures inside inner chamber, in accordance with a seventh embodiment of the present invention.

[0027] FIG. 6a is a block diagram representation of seperate battery system and controller enclosed in a chassis of an Electric Vehicle, in accordance with an eighth embodiment of the present invention.

[0028] FIG. 6b is a block diagram representation of combined battery system and controller enclosed in a chassis of an Electric Vehicle, in accordance with a ninth embodiment of the present invention.

[0029] Further, persons skilled in the art to which this disclosure belongs 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 disclosure so as not to obscure the figures with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

DETAILED DESCRIPTION

[0030] For the purpose of promoting an understanding of the principles of the disclosure, 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 disclosure is thereby intended. Such alterations and further modifications to the disclosure, and such further applications of the principles of the disclosure as described herein being contemplated as would normally occur to one skilled in the art to which the disclosure relates are deemed to be a part of this disclosure.

[0031] 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.

[0032] 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 a method. Similarly, one or more devices or subsystems or elements or structures or components preceded by "comprises... a" does not, without more constraints, preclude the existence of other devices, other subsystems, other elements, other structures, other 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 do not necessarily all refer to the same embodiment.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

[0034] Embodiments of the present disclosure will be described below in detail with reference to the accompanying figures.

[0035] Various embodiments of the battery system 100 are explained using FIGS 1a-6b.

[0036] In accordance to the first embodiment of the present invention, a battery pack system 100 and its sub-assemblies as illustrated in FIGS. 1a-1h are disclosed. The battery pack system 100 comprises an outer casing. The outer casing further comprises a left side wall 103, a right side wall 104, a top wall 105, a bottom wall 106, a front wall 101, and a back wall 102. The said walls 102 to 106 may be planar or may have suitable geometry that enhances the functionality of the battery pack system 100 or the electric vehicle comprising the battery pack as a whole. Functionalities may be related to aerodynamics, heat transfer, or structural for example, the front wall 101 and the back wall 102 may have a taper to enhance streamlines airflow and reduce aerodynamic drag. Walls 102 to 106 are coupled to each other for providing structural support to the battery system 100. The said walls 102 to 106 may be made up of a metal and welded, adhesively bonded or fastened together. The said metal walls 102 to 106 have an insulating material coating or layer on the outside, thereby thermally insulating the battery pack system 100 from the environment. Alternatively, the said walls 102 to 106 may be made up of thermally insulating material wherein, thereby eliminating the need of having thermal insulation on the outside. The thermally insulating material may be a plastic, glass fibre, carbon fibre, or other materials known in the art which are strong enough to provide structural integrity to the battery pack system 100. Further, the side walls 103 and 104 are hollow, such that, the side walls comprise channels 121 and 122 to allow air to flow through the side walls them. The channels 121 and 122 are made up of a metal and may further comprise fin structure for increased heat transfer.

[0037] Further, the battery pack system 100 comprise structure on the opening of the channels 121 and 122, termed as “gates”. The gates are sub-categorised into inlet gates 111 and 112, and outlets gates 114 and 113. The inlet gates 111 and 112 are coupled to the opening of channels 121 and 122 where the air enters into the channels 121 and 122, while the outlet gates 114 and 113 are coupled to the opening of channels 121 and 122 where the air exits from the channels 121 and 122. As illustrated in FIG.1a, gates 111 to 114 are hinged to the side walls 103 and 104. Herein, the term “hinged” refers to a mechanism or joint by which an object swings over another object. It is to be noted that the gates 111 to 114 may be hinged to the front wall 101 and the back wall 102 instead. Wherein, the gates 111 to 114 contains a material which can be attracted or repelled by a magnet, e.g. a ferromagnetic material or a magnet.

[0038] Further, electromagnets 151 to 158 are provided for the actuation of gates 111 to 114. Herein, an electromagnet is a type of magnet in which the magnetic field is produced by an electric current and the magnetic field disappears when the current is turned off. As illustrated in FIG. 1g and FIG. 1h, the electromagnets 151, 152, 155 and 156 are coupled to the front wall 101 and the electromagnets 153, 154, 157, 158 are coupled to the back wall 102. It is to be noted that, these electromagnets may be coupled to the side walls 104 and 103 instead. The said electromagnets 151 to 158 attract or release the gates 111 to 114, thereby closing and opening operation of the gates control the flow of air through the channels 121 and 122.

[0039] As illustrated in FIGS. 1b-1d, a battery module 130 is provided. The battery module 130 comprises battery cells 134 arranged in a suitable pattern to enhance the packing efficiency and heat transfer. A structure 131 provides structural support to the battery cell 134 and the overall battery module 130.

[0040] One or more pumps 170 are provided in each battery pack to generate pressure head and thus maintain required flow rate of the liquid coolant through liquid channels. The said pumps 170 may operate bidirectionally, such that, the liquid flow is to and fro. The to and fro manner of liquid flow ensures equal temperatures of battery cells 134 inside the battery module 130 as the heat is periodically absorbed in both front and reverse directions.The said liquid coolant can be water, water glycol mixture, coolant oil, or any other material known in the art.

[0041] For exemplary and simplicity purpose, the present disclosure and the corresponding drawings explain a battery pack system comprising “cylindrical battery cells”. However, it is to be noted that the various embodiments of the present disclosure are applicable for battery cells having different geometries in the battery pack system. Other types of battery cell geometries include prismatic cell geometry, pouch cell geometry, etc.

[0042] A heating element 140 is provided in the battery pack system 100. Herein, a heating element comprises resistors and produces heat when a current is passed through it. As illustrated in FIG. 1e, the heating element 140 is present inside the battery system 100. One or more heating elements may be present inside the battery pack systems.

[0043] As illustrated in FIG.1g, FIG.1h and FIG.5, inner chambers 161 and 162 are provided on the side walls 103 and 104. The fins 163 inside the inner chamber 161 provide enhanced heat transfer, as illustrated in FIG.5. FIG.1e and FIG.1f illustrate the assembly of battery modules 130 inside the battery pack system 100. Modules are stacked upon one another such that the inner chambers 161 and 162 are adjacent to each module 130.

[0044] In accordance with the second embodiment of the present invention, arrangement pattern of the battery cell 134 inside the battery module 130 is illustrated in FIG.2a. The battery cells 134 are arranged in an inline pattern. The liquid flow pattern is also illustrated in FIG.2a. In the said arrangement, the liquid flows in a straight line and touches the sides of the battery cell. For an equal flow rate, the pressure drop and the heat transfer is less as compared to a staggered arrangement described further.

[0045] In accordance with the third embodiment of the present invention, arrangement pattern of the battery cell 134 inside the battery module 130 is illustrated in FIG.2b. The battery cells 134 are arranged in a staggered pattern. The liquid flow pattern is also illustrated in FIG.2b. In the said arrangement, the liquid flows in zig-zag manner and touches almost complete wall of the battery cell. For an equal flow rate, the pressure drop and the heat transfer is more as compared to an inline arrangement.

[0046] In accordance with the fourth embodiment of the present invention, as illustrated in FIG.3a, the electromagnets 151 to 158 open the inlet and outlet gates 111 to 114 such that the upstream air flowing around the battery pack system 100 enters the outer channels 121 and 122. The one or more pumps 170 generate pressure head and thus maintain required flow rate of the liquid coolant through liquid channels such that, the heat produced during operation of the battery cells 134 is absorbed by the liquid and is discharged to the inner chambers 161 and 162 thereby maintaining desired operating temperature of the battery cell 134, and the heat absorbed by the inner chambers 161 and 162 is further transferred to the outer channels 121 and 122, and the air flowing through the channels 121 and 122 further absorbs the heat and discharges the heat to the environment.

[0047] The fourth embodiment of the present invention describes the mode of operation of the battery pack system 100 in hot climate. Herein, the term “hot climate” means the ambient air temperature being higher than operating temperature range of the battery cells. In an electric vehicle system comprising the battery pack system 100, the air flowing around the vehicle is channelized through the channels 121 and 122 to obtain cooling of the battery cells 134. Thus, a desired operating temperature and efficiency of the battery cells 134 is maintained.

[0048] In accordance with the fifth embodiment of the present invention, as illustrated in FIG.3b, the electromagnets 151 to 158 close the inlet and outlet gates 111 to 114 such that the upstream air flowing around the battery pack system 100 does not enter the outer channels 121 and 122. The heating element 140 is turned on and the one or more pumps 170 generate pressure head and thus maintain required flow rate of the liquid through liquid channels such that, the heat produced by the heating element 140 is absorbed by the liquid and is discharged by the battery cells 134, thereby heating up the battery cells 134 to a desired operating temperature.

[0049] The fifth embodiment of the present invention describes the mode of operation of the battery pack system 100 in cold climate. Herein, the term “cold climate” means the ambient air temperature being lower than operating temperature range of the battery cells. Thus, a desired operating temperature and efficiency of the battery cell 134 is maintained. The process of heating up the battery cells 134 may be carried until the desired temperature is achieved, after which the heating element 140 may be turned off and the heat produced during the operation of battery cell 134 may heat up itself.

[0050] In accordance with a sixth embodiment of the present invention, the battery pack 100 is equipped with a liquid reservoir. As used herein, a liquid reservoir 420 is a container that provides storage for additional liquid coolant. Furthermore, the liquid reservoir 420 has a filler cap 421 which is used to provide liquid coolant entrance into the battery pack system 100. The battery pack system 100 is also equipped with a pressure relief valve 410. As used herein, a pressure relief valve 410 is a mechanical or electronic device which regulates the pressure of coolant vapours inside the battery pack system 100. The pressure relief valve 410 can be a mechanical spring loaded device as known in the art or can be a solenoid valve based device controlled by an electronic controller. In case the battery heat rises due to thermal runaway of the battery cells 134 or any other unforeseen reasons, the liquid coolant may change its state from liquid to gas and the pressure inside the battery pack system 100 may rise to a dangerous level. In such case, the pressure relief valve 410 releases extra gases into the reservoir 420 as illustrated in FIG. 4.

[0051] The modes of operation of battery pack system 100, may be controlled by at least one controller suitably placed internally or externally of the battery system. The one or more controller controls and monitors the operation of the pumps 170, the electronic pressure relief valve 410, the heating element 140, and the electromagnets 151 to 158.

[0052] In accordance with a seventh embodiment of the present invention, an electric vehicle 600 is disclosed. As illustrated in FIG. 6a, the electric vehicle 600 comprises a chassis 610 configured to provide structure to the electric vehicle. Further, the electric vehicle comprises the battery pack system 100. Further, the electric vehicle comprises at least one controller 620 operatively coupled within the chassis 610, and is configured to control a plurality of devices within the electric vehicle, wherein the one or more controllers 620 are operatively coupled to sensors, thereby detecting the ambient air temperature and the battery cell temperature.

[0053] In accordance with an eighth embodiment of the present invention, an electric vehicle 600 is disclosed. As illustrated in FIG. 6b, the electric vehicle 600 comprises a chassis 610 configured to provide structure to the electric vehicle. Further, the electric vehicle comprises the battery system 100. Further, the electric vehicle comprises at least one controller 620 operatively coupled within the battery system 100, and is configured to control a plurality of devices within the battery system, wherein the one or more controllers 620 are operatively coupled to sensors, thereby detecting the ambient air temperature and the battery cell temperature.

[0054] While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person skilled in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.

[0055] 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 be combined well 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, orders of processes described herein may be changed and are not limited to the manner described herein. The scope of embodiments is by no means limited by these specific examples. Numerous variations, whether explicitly given in the specification or not, such as differences in structure, dimension, and use of material, are possible. The scope of embodiments is at least as broad as given by the following claims.