DESC:FIELD OF INVENTION
The present invention relates to battery temperature control system. The inventions in more specifically, but not particularly related to battery temperature control system for an electric motor vehicle or a hybrid electric vehicle.

BACKGROUND AND PRIOR ARTS
All electric or hybrid electric vehicles use batteries as a power source to drive electric motor, which in turn sends the power the wheels of the vehicle. It is known that that temperatures of batteries during their operations may affect their durability and charge-discharge efficiencies. At increased temperatures, breakdown of electrolytes in a battery gets accelerated and may shorten the life of the battery due to deterioration. On the contrary, lowered battery temperatures reduces reactivity of the electrodes and deteriorates the charge-discharge efficiency. It is of an importance to keep the temperature of a battery within its optimal temperature range, for preventing any reduction in the life of battery or degradation of it’s the charge-discharge efficiency.

In an electric vehicle, the temperature of a battery may be elevated due to heat generation during repeated charge-discharge cycles in the battery. The problem of elevated temperature is especially faced in the case of vehicles which employ a quick charging system for battery charging. In such vehicles, the driver may use the vehicle several times in the same day by rapidly charging the battery after it has been discharged. In this case, the temperature of the battery will increase more and more until it reaches threshold maximum temperature as the battery do not enough time to cool between two rapid charging cycles of the battery. Higher battery temperature also lead to increase in charging time of the batteries. Further, in the geographic where the ambient temperature is extreme i.e. too high or too low, problem of battery temperature management is further aggravated. When batteries operate at high temperature, vehicle travel range also reduces.

Usually vehicles, use multiple battery cells connected together to get desired power and range for the vehicle. Even when one or few of these battery cells keep operating at high temperature, it affects performance of other battery cells and degrade the all the battery cells leading to their early replacement and increase cost.
High battery cost and their frequent replacement is one of the key deterrent for large scale adoption of electric or hybrid-electric vehicle. Battery being one of the costly component of the vehicle, it is essential to preserve battery life and its charge-discharge efficiency to keep the vehicle running and maintenance cost under check. An effective battery temperature control system can solve this issue.
Similar problem are faced when the batteries are used as power source in stationary applications. An effective battery temperature control system is essential in such cases as well.
One of the most commonly used solution for battery temperature management is providing provision of fan or blower for actively providing cooling air to the batteries. However, this system usually proves to be insufficient if the ambient temperature itself is very high for e.g. above 40 degree Celsius.. In case where the ambient temperature is extremely cold for e.g. below -10 degree Celsius, battery needs a heating system. Marely providing fan will not fulfill this requirement.

Moreover, charging and discharging cycles of batteries get adversely affected at extreme temperatures. For e.g. Batteries do not get charged at temperature higher than 44 degree Celsius and do not get discharged at temperature higher than 58 degree Celsius. In such scenario, if a vehicle is provided with regenerative charging and batteries are at very high temperatures, regenerative charging system may not get used effectively.

To address this shortcoming of the above system, an evaporator is employed to cool the air from the fan or blower and then circulating around the batteries. However, use of the evaporator entails deployment of other associated components such as compressor, condenser, tubing, etc. In case all these components are packaged together in close vicinity which leads to system becoming complex, bulky

Another known solution used for battery cooling is use of a secondary fluid like ethylene glycol between the cells of the pack of batteries. The primary fluid i.e. coolant is used to cool the secondary fluid which in turn cools the batteries. Further, deploying of phase change material between cells of the batteries makes system complex and has a problem of leakage due to use the secondary fluid. This systems cannot be continentally adopted for removable batteries.

Thus, there is need of an improved battery temperature control system which can effectively address the shortcoming and overcome the limitations of conventional systems stated above.

OBJECTIVES OF THE INVENTION

Accordingly, objective of the invention is to provide a battery temperature control system which work without essentially using an active air circulation.
Another objective of the invention is to provide a battery temperature control system which is not complex and can be continentally adopted for removable batteries.
Yet another objective of the invention is to provide a battery temperature control system which has no or minimal moving parts.

Yet another objective of the invention is to provide a battery temperature control system which can effectively manage battery temperature in diverse temperature geographies.

SUMMARY OF INVENTION

A battery temperature control system comprising at least one evaporator, condenser, a compressor and at least one battery wherein; said temperature control system comprises at least two enclosures wherein;
a first enclosure is placed inside a second enclosure forming a space there between; and said battery is housed inside the first enclosure; and
said evaporator is positioned within any one of the enclosures.

A battery temperature control system wherein the evaporator is preferably positioned in the space between the first enclosure and the second enclosure.

A battery temperature control system comprising at least two distinct air passages for hot and cold air wherein; a first air passage constituted by a first enclosure and a second air passage constituted by a second enclosure. Preferably the first air passage is constituted by at least one battery housed inside first enclosure

In the battery temperature control system, when the first enclosure carries hot air, the second enclosure carries the cooled air whereas when the first enclosure carries cold air, the second enclosure carries the hot air.

The first enclosure may be provided with at least one opening, preferably on the top surface for air to enter or exit from the first enclosure and on the lower side of the first enclosure, preferably on the bottom surface for air to enter into the first enclosure. Alternatively, air may enter into first enclosure from top surface and exit the first enclosure from bottom surface. Further, openings may also be provided on side surface to exit or enter the air. The air may enter into first enclosure from top side and exit from the side surfaces of the first enclosure or vice versa. The evaporator is preferably placed at the upper end of first enclosure, preferably on the top surface of the first enclosure, preferably in a space between, the first enclosure and the second enclosure.

The first enclosure may not be completely closed structure but may be in the form of frame structure providing mounting arrangement for batteries. The batteries are mounted inside frame structure such that it provides space between two batteries and a space between battery and outer enclosure to circulate the air. The outer enclosure may be completely closed such that no outside air can enter into said temperature control system. A drain hole is provided in the box so as to remove any moisture or water of condensed air. Additionally, to achieve more effective cooling through air circulation a duct or air passages may be provided in the path of air. This helps in directing the air at targeted surface of batteries to achieve effective cooling. The air duct or air passage is designed such that more air is directed towards area where more heat is generated for example where two battery surfaces are required to be cooled as compare to a space where only one battery surface is to be cooled. The space between two batteries gets more air flow whereas the space between battery and enclosure is supplied with lesser amount of air flow.

One or more batteries connected together can be placed inside the first enclosure. The arrangement of the batteries inside the first enclosure is such that batteries can be easily removed and replaced with other batteries. The first enclosure or batteries may be provided with guide rails such as to slide the batteries within enclosure. This facilitates easy installation and removal of batteries from the enclosure. Further, batteries packaged and oriented such that their maximum surface area is exposed to cooling air for efficient cooling.

Based on the number of batteries placed inside the first enclosure and heat load produced by the batteries, number of evaporators deployed can be changed. Further, positioning of the evaporators is preferably made to efficiently achieve optimal temperature for the batteries. In one of the embodiments of the invention the evaporators are placed at the top end of the first enclosure in a space between, the first enclosure and the second enclosure.

The first enclosure comprises battery securing arrangement including belts for securing at least one battery. The second enclosure is provided with at least one door such that the door is opened to access the battery placed inside first enclosure. The second enclosure is also provided with a layer of insulation material to prevent any heat transfer. Battery is packaged and oriented inside first enclosure horizontally, vertically or inclined such that maximum surface area of each battery is exposed to cooling air for efficient cooling.

In yet another embodiment of the invention, the first enclosure is also provide with openings on the side surface as well. Evaporators may be positioned in sideward space between the first enclosure and the second enclosure.

The enclosures for the batteries can be designed in a shape based on packaging space available in the vehicle and batteries to be accommodated. The evaporator/s in the enclosure are connected to other components of the temperature control system such as compressor, condenser, tubes carrying the coolant, etc. which are placed outside the enclosures. This helps to maximize the space inside the enclosure for batteries and efficient air circulation. It also helps to avoid complexity inside the enclosure and facilitates easy installation and removal of batteries.

As the associated components of the battery temperature control system except evaporator are positioned outside the enclosure, the system offers freedom in packaging of these components within space available in vehicles. This also ensure easy assembly and maintenance of these components.

The enclosure for batteries can be made of different material such as aluminum, plastic, etc. based on design requirements.

According to one of the embodiment, the battery temperature control system does not employ fan or blower for the circulation of air within the enclosures. Instead, the system rely on passive air circulation caused by temperature difference between air heated by the batteries and air cooled by the evaporators.

When current is drawn from batteries placed inside the first enclosure, batteries get discharged and heated. This heat is absorbed by the air surrounding the batteries. Density of this heated air reduces and the heated air rises up. The heated air exits from the opening on the top end of the first enclosure into the space between first enclosure and second enclosure. The evaporators are placed in this space readily absorbs heat from the hot air and cools the air making is dense and heavy.

Cooled dense air moves downward through side passage between the first enclosure and the second enclosure. The cooled air then enters the first enclosure through the openings at the bottom of the first enclosure and reaching back to the batteries for cooling. Thus, force air circulation through fan or blower is not needed essentially. The battery temperature control system operate through passive air circulation and thus reduces energy needed for battery temperature control. This in turn helps to increase vehicle driving range and improves battery life. The battery temperature control system helps is easy adoption of removable battery system. Further, the system can be used in diverse temperature range ranging from very cold to very hot.

Though the fan is not essential component it may be provided to further enhance the air circulation and temperature control, fan or blower (not shown) may be provided within or outside the inner/first enclosure. Preferably, fan is provided below evaporator inside first enclosure such that fan draws the air which forces the air to flow over evaporator surface and get cool.

In yet another embodiment of the invention a heater may be provided within the space between the first and second enclosures to address the issue of over cooling of the batteries. The heater can be activated when batteries are overcooled to increase the temperature of batteries. The issues is especially faced in geographies where the ambient temperature falls close to zero or go to sub-zero levels.

In yet another embodiment of the invention, evaporator and condenser are made inter convertible by employing a reversing valve. This arrangement eliminates the need of providing a separate heater provision for increasing the battery temperature when the ambient temperature is very cool.

The battery temperature control system can be easily adopted for various type of vehicles such as two wheeled such as motorcycle, scooter, etc., three wheeled such as auto rickshaw and four wheeled vehicles such as quadricycles, cars, etc. Further, the system can be easily adopted when the batteries are used as power source in stationary applications.

In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF DRAWINGS
In the drawings:

Figure 1A is an orthogonal view of battery temperature control system according to one of the embodiment of the invention.

Figure 1B is a front view of the battery temperature control system according to Figure 1A.

Figure 1C is an orthogonal view of the battery temperature control system according to Figure 1A with doors open.

Figure 2 is an orthogonal view of a second enclosure or an outer enclosure of battery temperature control system according to Figure 1A with doors open.

Figure 3 is an orthogonal view of a first enclosure or an inner enclosure along with batteries and evaporators of the battery temperature control system according to Figure 1A.

Figure 4 is an orthogonal view of a first enclosure or an inner enclosure with evaporators but without batteries of the battery temperature control system according to Figure 1A.

Figure 5A is a front view of a first enclosure or an inner enclosure along with batteries and evaporators according to Figure 3.

Figure 5B is a side view of a first enclosure or an inner enclosure along with evaporators according to Figure 3.

Figure 5C is a top view of a first enclosure or an inner enclosure along with evaporators according to Figure 4.

Figure 5D is a bottom view of a first enclosure or an inner enclosure according to Figure 4.

Figure 6 is a close up view of a battery holding arrangement in the battery temperature control system according to Figure 1A to 3.

Figure 7 is an exploded view of the battery temperature control system according to Figure 1A.

Figure 8 is an orthogonal view of the removable battery used in the battery temperature control system according to Figure 1A.

Figure 9A is an orthogonal view of the battery temperature control system according to Figure 1A along with other components of temperature control system.

Figure 9B is a top view of the battery temperature control system according to Figure 1A along with other components of temperature control system.

Figure 10A shows air circulation path within the battery temperature control system according to Figure 1A.

Figure 10B shows battery surface temperature profile within the battery temperature control system according to Figure 1A when the system is activated.

Figure 10C shows air circulation velocity profile within the battery temperature control system according to Figure 1A when the system is activated.

Figure 11A shows air circulation path within the battery temperature control system according to another embodiment of present invention

Figure 11B shows a duct used as a part of first enclosure of the system according to Figure 11A.

Figure 11C shows battery surface temperature profile within the battery temperature control system according to embodiment of figure 11A when the system is activated.

Figure 11D shows air circulation velocity profile within the battery temperature control system according to Figure 11A when the system is activated

Figure 12A shows air circulation path within the battery temperature control system according to yet another embodiment of present invention

Figure 12B shows battery surface temperature profile within the battery temperature control system according to embodiment of figure 12A when the system is activated

Figure 12C shows air circulation velocity profile within the battery temperature control system according to Figure 12A when the system is activated

Figure 13A shows a vehicle mounted with the battery temperature control system according to any one of the embodiment of present invention.

Figure 13B shows a frame structure of the vehicle of Figure 13A for mounting of the battery temperature control system according to any one of the embodiment of present invention.

Figure 13C shows the battery temperature control system according to Figure 1A mounted on the frame structure of the vehicle shown in Figure 10B.

The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION

Description of preferred but non-limiting embodiments of the present invention will now follow with reference to the above drawings.

Referring to figure 1A to 8, the battery temperature control system 100 includes a second enclosure 50 which from here on referred as an outer enclosure and a first enclosure 150 which from here on referred as an inner enclosure. Batteries 200 are packaged inside the inner enclosure 150.

As shown in figure 2, the outer enclosure 50 is box shaped and provided with doors 52 having seals. Provision of doors 52 helps to open the outer enclosure 50 for easy loading and unloading of batteries 200. The outer enclosure 50 can be made up of sheet metal or plastic. Further, it may be provided with insulation layer from inner surface 54 for keeping ambient temperature effect on the temperature within the enclosure minimal. The outer enclosure 50 is provided with a mounting tray 48 which forms the base of the enclosure 50. The mounting tray 48 provides support to the inner enclosure 150 and batteries 200 within it. The mounting tray 48 is also provided with multiple bolting provisions 110 which facilitates easy mounting of the battery temperature control system 100 onto the vehicle frame. Alternately, the battery temperature control system 100 can be directly welded onto the vehicle frame.

It is to be noted that the shape and material of the outer enclosure 50 can be varied based on design requirements and space available in the vehicle for packaging of the battery temperature control system 100.

Referring to figure 3 to 8, the battery temperature control system 100 includes the inner enclosure 150 placed inside the outer enclosure 50. The inner enclosure 150 is the form of a battery support frame 215 for mounting the batteries 200. The battery support frame 215 is made of the sheet metal tubular sections 235 welded together to form the compartments 205 for inserting the batteries 200. The present embodiments shows the arrangement of three batteries 200 however, the number and shape compartments 205 can be kept as per the design requirements.

Each compartment 205 is provided with L-shape battery support sections 245 at its all four corners. The arrangement of sections provide additional support to the batteries 200 and make the battery support frame 215 rigid. The battery support sections 245 is also lined with a lining material 240 such as nylon. The lining material 240 facilitates sliding of the batteries 200 within the battery support frame 215 and thus helps in easy installation and replacement of batteries 200 within the enclosure 150. Additionally Battery 200 removal is eased further by provision of guiding rails on the batteries and on the battery support section 245. Batteries 200 may be allowed to slide within the inner enclosure 150 for installation and removal with guide rails. A guide rail is provided for each battery 200. Batteries 200 may be provided with a handle to further assist installation and removal.

The inner enclosure 150 is covered by sheet metal plates on sides to form the side surfaces 160. The side surface 160 are provided with multiple openings 220 for circulating air to and from the outer enclosure 50 to the inner enclosure 150. The rear side of the inner enclosure 150 is not covered and the inner enclosure 150 share the same rear wall as that of the outer enclosure 50. In an alternate arrangement, the inner enclosure 150 may also be provided with rear wall.

The bottom surface of the inner enclosure 150 is covered with a bottom wall 170. The bottom wall 170 is provided with the opening 230 at the center for passage of air. The size of opening 230 is such that it exposes all the batteries 200 within the inner enclosure 150 to the air flow. This ensures the efficient heat transfer between the air and the batteries 200.

The top surface 165 of the inner enclosure 150 is provided with a raised structure 167 from the horizontal level. The raised structure 167 is provided is provide with the opening 225 at its top surface for passage of air. The raised structure 167 has slanting walls 168L and 168R on which evaporators 152 are installed. The design of the raised structure 167 is such that it traps the air and creates a required density difference for efficient convection within the battery temperature control system 100. The number and size of evaporators 152 can be changed based on number of batteries and heat load.

Batteries 200 are installed in the compartments 205 of the battery support frame 215 by sliding the batteries 200 within the compartments 205. The battery cables 208 are connected at the one end to the battery 200 and on the other end to the coupler 210. The coupler 210 connects the batteries 200 to the wiring harness (not shown) which is connected to other electrical components such as motor. Battery packaging and battery orientation is designed such that maximum surface area of the batteries 200 get exposed to air entering from the bottom of the inner enclosure 150.

For holding the batteries 200 in position while vehicle is in drive mode and avoid battery movement, a provision of a battery holding arrangement including belts 155 is made. In present embodiment, two belts 155 are provided to hold batteries 200 in position. The belts 155 are fixed at one end and on the other end the belt is provided with loop 157. A hook 156 fixed on the outermost vertical member of the battery support frame 215 is provided. The loop 157 of the belt 155 fits into the hook 156 and secures the batteries 200 in the position. Provision of the belt 155 and the hook 156 helps in easy disengagement of the belt 155 for removal and installation of batteries 200. In an alternate embodiment, for keeping the batteries 200 in position, locking plates may be provided on the battery support frame 215 and the batteries 200.

The evaporator 152 inside the battery temperature control system 100 is connected to compressor 310 and condenser 320 through coolant tubes 330. The compressor 310 and condenser 320 are placed outside the battery temperature control system 100 and packaged within the vehicle as per space availability. In yet another embodiment of the invention, evaporator 152 and condenser 330 are made inter convertible by employing a reversing valve (not shown). This arrangement helps to increase the battery temperature when the ambient temperature is very cool. Alternately, a heating arrangement may also be provided for increasing the battery temperature.

Referring to Figure 10A to 10C, during vehicle operation, batteries 200 placed inside the inner enclosure 150 get discharged and heated. This heat is absorbed by the air surrounding the batteries. Density of this heated air reduces and the heated air rises up along the first air path 35A and trapped under the raised structure 167 and exits through opening 225 into the space between the inner enclosure 150 and the outer enclosure 50 along the second air path 35B. The evaporators 152 installed on slanting walls 168L and 168R of the raised structure 167 readily absorbs heat from the hot air and cools the air making is dense and heavy.

Cooled dense air moves downward through side passage between the inner enclosure 150 and the outer enclosure 50. The cooled air then enters the inner enclosure 150 through the openings 230 at the bottom of the inner enclosure 150 and reaching back to the batteries 200 for cooling. It can be seen from figure 10B that top edges of batteries are is high temperature zone 4 however rest of the air inside the inner enclosure 150 remains in low temperature zone 3, 2 and 1 which is below 30 degree Celsius ensuring effective battery cooling. Air between the inner enclosure 150 and outer enclosure 50 remain in low temperature zone 1.

Referring to figure 10C, air velocity around the boundaries of the outer enclosure 50 remains in high velocity region 14 and 15. Majority of the air within inner enclosure 150 and space between the inner enclosure 150 and the outer enclosure 50 remain in moderately high velocity region 12 and 13 with velocity ranging between 0.05 m/s to 0.15 m/s. Thus ensuring effective passive air circulation.

Thus, force air circulation through fan or blower is not needed. The elimination of the fan lead to reduction of battery load, which in turn helps to increase vehicle travel range and prevent battery heating. Number of moving parts, ease of assembly and maintenance is increased by avoiding fan. Further, it also helps in reducing initiate system cost and maintenance costs.

Though the battery temperature control system 100 does not essentially need a fan however to further enhance the air circulation and temperature control, fan or blower (not shown) may be provided within or outside the inner enclosures 150 or the outer enclosure 50.

Referring to figure 11A to 11D, illustrating another embodiment of the present invention wherein, the inner enclosure 150 is used to hold three batteries 200 in vertical position such that a space is left between two batteries for air circulation. To enhance the cooling effect a fan 250 is provided in this embodiment. At least one evaporator 152 is mounted at the top portion of the first enclosure or inner enclosure 150 preferably in a space between the outer enclosure 50 and the inner enclosure 150. The fan 250 is mounted below the evaporator and draws the air. This forces the air to flow over evaporator surface and get cool. The cooled air becomes dense and flows further in downward direction along the battery surface and absorbs heat from the battery surface as it moves in downward direction along the first air path this is indicated by arrows 35A in figure 11A. The air exits from the bottom side 230A of first enclosure 150. The heated air then flows from a space between the first enclosure and outer enclosure. As the side surface of the first enclosure are left open the air absorbs the heat from the sides of battery surface while moving in upward direction along second air path indicated by arrows 35B. The fan again draws this air towards evaporator. This continues the cycle by creating an active flow of air.

Further, the first enclosure 150 according to the embodiment of figure 11A comprises a duct 350 as illustrated in figure 11B. A provision for mounting the fan 250 and evaporator 152 on the duct 350 is provided. The duct 350 also comprises air directing means which helps in directing the air in the downward direction towards battery surface and collects the heated air and allows it to flow towards evaporator 152 as shown in figure 11A. The duct 350 is mounted on top surface of first enclosure 150.

Figure 11C shows the temperature pattern once the system according to figure 11A is active. The temperature near evaporator 152 is maintain around 10 degree which is cooler region 1. The cool air is diverted towards the battery surface. The area around battery is in the region 2 or 3 where temperature is maintained below 25 degrees. Figure 11D represents velocity pattern of air. Regions 14 and 15 are high velocity regions which are around the battery surface. The fan 250 draws the air which helps is maintaining air flow rate higher near battery and helps in rapid cooling.

Figure 12A to 12C represents yet another embodiment of the present invention according to which there are four batteries 200 mounted horizontally inside a first enclosure 150 comprising battery holding structure. An evaporator 152 and a fan 250 are mounted centrally on the top portion of the first enclosure 150 or a space between outer enclosure 50 and first enclosure 150. During operation, the fan 250 draws the air which flows over the evaporator surface and gets cooled. This cooled air then enters a duct (not shown) which distributes the air and directs it horizontally towards battery surface. The heated battery surface gets cooled by the cool air which then exits the first enclosure 150 from side surface. The heated air is again collected, cooled by evaporator 152 and again circulated using fan 250.

Figure 12B illustrate temperature profile with the system according to figure 12A is employed. The area around battery surface is maintained cooler indicated by region 1, 2 and 3. The temperature is maintained below 25 degrees in these areas. The 12C represent velocity profile which shows the air is maintained higher in the region 13, 14 and 15 around battery surface.

The air duct or air passages according to the present invention are designed such that more air is directed towards area where higher heat is generated specifically where two battery surfaces are required to be cooled as compare to a space where only one battery surface is to be cooled. The space between two batteries gets more air flow whereas the space between battery and enclosure is supplied with lesser amount of air flow.

As an exemplary embodiment, figure 13A to figure 13C shows installation of the battery temperature control system 100 in a three wheeled vehicle 500. The battery temperature control system 100 is packaged in the rear compartment 550 of the vehicle 500 behind the passenger seat and under the luggage compartment of vehicle 500.

For installation of the battery temperature control system 100, an H-frame 400 is provided. The H-frame 400 is mounted on the cross members 430 and 420. The battery temperature control system 100 is fixed to the frame 400 through bolting provisions 110 provided on the battery temperature control system 100. Alternately, the battery temperature control system 100 can be welded to the frame 400 and formed as separate subassembly and then mounted on vehicle frame 450.

It is to be noted that, the battery temperature control system 100 can be suitably adopted for various type of vehicles such as two wheeled such as motorcycle, scooter, etc., three wheeled such as auto rickshaw and four wheeled vehicles such as quadricycles, cars, etc. Further, the battery temperature control system 100 can be easily adopted when the batteries are used as power source in stationary applications.

The battery temperature control system 100 essentially operate by passive air circulation. This helps to reduces energy needed for battery temperature management and avoid drawing of the energy from battery for battery cooling or heating. Reduction in energy consumption lead to increase in vehicle driving range and improvement in battery life.

Further, the battery temperature control system 100 facilitates easy adoption of removable battery system. The system can be easily used in geographies of diverse temperature range ranging from very cold to very hot. The battery temperature control system of present invention is less complex, less bulky, less costly and easy to assemble and maintain.

The applicant is relying upon the provisional specification and the drawings filed with the application previously.

All variations and modifications obvious to the skilled persons are within the scope of the invention
,CLAIMS:1. A battery temperature control system comprising
at least one evaporator, a condenser, a compressor and at least one battery wherein; said temperature control system comprises
at least two enclosures wherein;
a first enclosure is placed inside a second enclosure forming a space there between; and said battery is housed inside the first enclosure; and
said evaporator is positioned within any one of the enclosures.

2. A battery temperature control system as claimed in claim 1 wherein; the evaporator is positioned in the space between the first enclosure and the second enclosure.

3. A battery temperature control system as claimed in claim 1 wherein; at least two enclosures forms at least two distinct air passages for hot and cold air wherein;
a first air passage constituted the first enclosure; and
a second air passage constituted by a second enclosure.

4. A battery temperature control system as claimed in claim 3 wherein; the first air passage is constituted by at least one battery housed inside first enclosure.

5. A battery temperature control system as claimed in claim 3 wherein, first enclosures carries cool air and second enclosure carries hot air or vice versa.

6. A battery temperature control system as claimed in claim 1 wherein; the first enclosure is provided with at least one opening on the top surface for air to enter or exit from the first enclosure and at least one opening on the lower surface or on side surface of the first enclosure for air to exit or enter into the first enclosure such that at least two openings forms a close loop air circulation passage.

7. A battery temperature control system as claimed in claim 4 wherein; at least one opening provided on the top surface of first enclosure for positioning the evaporators in upward space between the first enclosure and the second enclosure.

8. A battery temperature control system as claimed in claim 1 wherein; at least one battery is removably placed inside the first enclosure using guiding means provided on battery or first enclosure.

9. A battery temperature control system as claimed in claim 1 wherein; the first enclosure is provide with opening on the side surface for positioning the evaporator in sideward space between the first enclosure and the second enclosure.

10. A battery temperature control system as claimed in claim 1 wherein; at least one evaporator is connected to other components of the temperature control system comprising compressor, condenser, tubes carrying coolant and are placed outside the first and second enclosures.

11. A battery temperature control system as claimed in claim 1 wherein; the enclosure for batteries is made from metal or non-metal material including aluminum or plastic.

12. A battery temperature control system as claimed in claim 1 wherein; any one of the enclosure is provided with a fan or a blower for active air circulation.

13. A battery temperature control system as claimed in claim 12 wherein; the fan or a blower is mounted within the first enclosure below evaporator.

14. A battery temperature control system as claimed in claim 13 wherein; the first enclosure is provided with an air duct for directing the cool air towards the battery surface.

15. A battery temperature control system as claimed in claim 14 wherein; the air duct is designed such that more air is directed towards area where higher heat is generated as compare to area where lesser heat is generated.

16. A battery temperature control system as claimed in claim 1 wherein; the second enclosure is provided with at least one door such that the door is opened to access the battery placed inside first enclosure.

17. A battery temperature control system as claimed in claim 1 wherein; the space between the first and second enclosures comprises a heater.

18. A battery temperature control system as claimed in claim 1 wherein; evaporator and condenser are made inter convertible by employing a reversing valve.

19. A battery temperature control system as claimed in claim 1 wherein; the first enclosure comprises battery securing arrangement including belts for securing at least one battery.

20. A battery temperature control system as claimed in claim 1 wherein; the second enclosure is provided with a layer of insulation material to prevent any heat transfer.

21. A battery temperature control system as claimed in claim 1 wherein; battery is packaged and oriented horizontally, vertically or inclined such that maximum surface area of each battery is exposed to cooling air for efficient cooling.

22. A battery temperature control system as claimed in claim 1 wherein; said temperature control system is adopted for a vehicle including two wheeled, three wheeled or a four wheeled vehicles.

23. A battery temperature control system as claimed in claim 22 wherein; the vehicle is provided with at least one battery as a power source.