WO2017130168A1

WO2017130168A1 - A casing for an energy storage device

Info

Publication number: WO2017130168A1
Application number: PCT/IB2017/050477
Authority: WO
Inventors: Shubhankar GHOSH; Anirudh REDDY; Adhithya SRINIVASAN
Original assignee: Ather Energy Pvt. Ltd.
Priority date: 2016-01-31
Filing date: 2017-01-30
Publication date: 2017-08-03

Abstract

A casing [100] for an energy storage device to effectively dissipate the heat from the casing [100] is disclosed in the present invention. The casing [100] comprises an inner portion [104] and an outer portion [102], wherein the inner portion [104] comprises a plurality of ribs of variable dimension and/or variable density and wherein the outer portion [102] comprises a plurality of fins of variable dimension.

Description

A CASING FOR A ENERGY STORAGE DEVICE

FIELD OF THE I VENTION

The present invention generally relates to a casing for an energy storage device and more particularly relates to variable sized fins and ribs to be fitted against the casing.

BACKGROUND OF THE INVENTION

The following description of related art is intended to provide background information pertaining to the field of the present disclosure. This section may include certain aspects of the art that may be related to various aspects of the present disclosure. However, it should be appreciated that this section be used only to enhance the understanding of the reader with respect to the present disclosure, and therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.

In the present world, there is a wide range of applications of energy storage devices in various fields such as mobile industry, automobile industry, home appliances, etc., wherein said energy storage devices may be, but not limited to, lead acid battery, nickel metal hydride battery, lithium ion battery and capacitor.

Besides a variety of applications of the energy storage devices, the energy storage device poses various limitations. One of the limitations is the heating problem in the energy storage device. This heating may arise due to various factors. For instance, when the cells are not chemically uniform, the heating and cooling time and rate of each individual ceil varies, thereby leading to disparity in the temperature of the casing of the energy storage device. This disparity in the temperatures for the casing of the energy storage device may be due to mounting structures since they play a vital role in controlling the heating of the energy storage device. This may hamper the device's life and performance, in another instance, heat also gets accumulated inside the casing due to heating of its various components such as a motor and a charger that may further result in deterioration of the cell/ battery capacity/casing.

Furthermore, in an instance, when air is used to cool down the vehicle components, the air becomes hotter while travelling from the steering side to the side opposite to the steering side. Therefore, the air present at the side opposite to the steering side is hotter than compared to the steering side, thereby resulting in reduced cooling efficiency of the air.

The inherent tendency of the components present in the energy storage device to generate significant heat during charging and discharging, loss of cooling efficiency of air and various above mentioned factors results in higher demand thermal management techniques, thereby leading to introduction of ribs and fins in the casing of the energy storage device. The ribs and the fins present in the casing of the energy storage device increase heat transfer area i.e. there is considerable amount of area for flow of heat subsequently reducing temperature.

Therefore, there is a need for a system/casing/method that not only substantially reduces the heat accumulation inside the casing of the energy storage device but also facilitates heat removal depending upon the heat gradient/cooling gradient inside the casing.

OBJECTS OF THE INVENTION

This section is provided to introduce certain objects and aspects of the disclosed methods and systems in a simplified form that are further described below in the detailed description.

It is the primary object of the present invention to provide an energy storage device casing with ribs that reduces accumulation of the heat inside the casing. Another object of the present invention is to provide an energy storage device casing with fins to reduce accumulation of the heat inside the casing.

SUMMARY OF THE INVENTION

This section is provided to introduce certain objects and aspects of the disclosed methods and systems in a simplified form that are further described below in the detailed description. This summary is not intended to identify the key features or the scope of the claimed subject matter.

In view of the shortcomings of existing methods and systems, as discussed in the background section and the objectives of the present invention, the present invention relates to a casing for an energy storage device comprising an inner portion that further comprises a plurality of ribs of variable dimension extending from at least one first surface to at least one second surface, wherein the at least one first surface and the at least one second surface are present inside the inner portion of the casing. The inner portion also comprises of a plurality of cells supported by the plurality of ribs.

Another aspect of the present invention relates to a casing for the energy storage device comprising an inner portion that further comprises a plurality of ribs having variable density extending from at least one first surface to at least one second surface, wherein the at least one first surface and the at least one second surface are present inside the inner portion of the casing. The inner portion also comprises of a plurality of cells supported by the plurality of ribs.

Yet another aspect of the present invention relates to a casing for the energy storage device comprising an outer portion having plurality of fins wherein the fins have variable density.

BRIEF DESCRIPTION OF THE DRAWING The accompanying drawing/s, which are incorporated herein, and constitute a part of this invention, illustrate exemplary embodiments of the disclosed methods and systems in which like reference numerals refer to the same parts throughout the different drawings. The preferred embodiments of the present invention can be best understood when read in conjunction with the following drawing:

Figure 1 illustrates a perspective view of a casing for an energy storage device in accordance with the exemplary embodiment of the present invention.

It may be evident to skilled artisans that elements in the figure are only illustrative, for simplicity and clarity, and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figure may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following description, for the purposes of explanation, various specific details are set forth in order to provide a thorough understanding of the disclosed embodiments. It will be apparent, however, that the disclosed embodiments may be practiced without these specific details. Several features described hereafter can each be used independently of one another or with any combination of other features. However, any individual feature may not address any of the problems discussed above or might address only some of the problems discussed above in the background section. Some of the problems discussed above might not be fully addressed by any of the features described herein.

The present invention encompasses a casing of an energy storage device, wherein the casing comprises of a plurality of ribs with at least one of variable dimension and variable density. Additionally, the casing comprises a plurality of fins with variable density. The casing is further configured to reduce the accumulation of heat inside the casing.

As used herein, an 'energy storage device' refers to an apparatus/device/unit configured to store energy, more particularly, electric energy. The energy storage device may include, but not limited to, lead acid battery, nickel metal hydride battery, lithium ion battery, a capacitor and any such device as may be obvious to person skilled in the art.

As used herein, a 'casing' is configured to support/house the energy storage device. The application of the casing of the energy storage device may include, but not limited to, a vehicle, a control system, a charging unit, a motor and any computing device such as mobile, laptop, pager, etc. Further, the casing may be circular in shape or may be having at least three side walls.

As used herein, the 'vehicle' may be, but not limited to, a two-wheeler, three- wheeler and a four-wheeler. Also, the vehicle may include, but not limited to, an electric vehicle, a hybrid vehicle, a conventional vehicle, an alternative fuel vehicle and any such vehicle as may be obvious to person skilled in the art.

As used herein, the 'cell characteristics' may include, but not limited to, cell voltage, cell capacity, cell discharge curve and any such characteristic as may be obvious to person skilled in the art.

As used herein, the 'energy storage device characteristics' may include, but not limited to, size of the energy storage device and any such characteristic as may be obvious to person skilled in the art.

As illustrated in FIG.l, the present invention relates to a casing [100] for the energy storage device, wherein the casing comprises of an inner portion [104] and an outer portion [102]. The inner portion [104] of the casing [100] comprises at least one of a plurality of ribs, a plurality of cells, cell spacers and cooling fans, wherein said ribs may be spatially arranged in the casing [100]. Further, a thermal conducting material is present in the inner portion [104] of the casing [100] that allows the heat to be transferred to the casing [100] walls.

The plurality of ribs extends from at least one first surface to at least one second surface of the inner portion [104], wherein the at least one first surface and the at least one second surface are present inside the inner portion [104] of the casing [100]. The plurality of ribs is further configured to support the plurality of cells in order to facilitate the heat transfer to the casing [100]. The plurality of cells may also be placed on the cell spacers and are further supported by the plurality of ribs.

The present invention encompasses the plurality of ribs of variable dimension, wherein said dimension may include at least one of angular dimension, spherical dimension, height, length, width and thickness and wherein the variation may be based upon at least one of heat gradient, cell characteristics and energy storage device characteristics.

In an exemplary embodiment, the vehicle's energy storage device casing [100] comprises of four side walls, wherein the wall facing the steering is termed as the steering side wall. Here, the length of the plurality of ribs substantially increases from the steering side wall of the casing [100] to its opposite side wall, wherein said increase is based upon the fact that the air becomes hotter while travelling from the steering side wall to its opposite side wall, thereby resulting in reduced cooling efficiency of the air.

Further, in an exemplary embodiment, the vehicle's energy storage device casing [100] comprises of four side walls, wherein the walls adjacent to the steering side wall are termed as rail side walls. Here, the length of the plurality of ribs substantially increases from the rail side walls to a centre of the casing [100] since more heat is accumulated at the centre as compared to the rail side walls. Furthermore, the dimension of the adjacent ribs extending from the at least one wall of the inner portion [104] to the opposite wall of the inner portion is variable.

The present invention further encompasses that the plurality of ribs with variable rib density extend from the at least one first surface to the at least one second surface, wherein the density refers to the spacing between two adjacent ribs and wherein the variation may be based upon at least one of heat gradient, the cell characteristics, the energy storage device characteristics and dissipation of heat.

In an exemplary embodiment of the vehicle's energy storage device casing [100], the density of the plurality of ribs substantially increases from the steering side wall of the casing [100] to its opposite side wall, wherein said increase is based upon the at least one of heat gradient, thermals of the casing [100], the energy storage device characteristics and dissipation of heat. In yet another exemplary embodiment of the vehicle's energy storage device casing [100], the density of the plurality of the ribs increases from the side rail walls towards the centre of the casing [100].

Further, the present invention encompasses that the plurality of ribs comprise of varied structures including, but not limiting to, a wavy structure, a zigzag structure and any such non-linear structure as may be obvious to a person skilled in the art. The primary advantage of using said non-linear structured ribs is that it increases the surface area for the heat transfer as compared to linear structured ribs, thereby increasing the efficiency of the ribs.

Additionally, the outer portion [102] of the casing [100] comprises a plurality of fins. In an exemplary embodiment, the plurality of fins may be present in circular, triangular, rectangular, square in cross section or any such cross section as may be obvious to a person skilled in the art, while in another exemplary embodiment, the fins may be present in pyramidal, cylindrical, prismatic, conical or any such shape as may be obvious to a person skilled in the art.

The present invention also encompasses the plurality of fins with variable fin density, wherein the density refers to the spacing between adjacent fins and wherein the variation of the density may be based upon at least one of heat gradient, the cell characteristics, the energy storage device characteristics and dissipation of heat.

In an exemplary embodiment of the vehicle's energy storage device casing [100], the density of the fins is lesser towards the steering side wall as compared to its opposite side wall of the casing [100].

Further, the present invention also encompasses the plurality of fins having variable dimension, wherein the dimension may include at least one of angular dimension, spherical dimension, height, length, width and thickness and wherein variation in the dimension of the plurality of fins may be based upon at least one of heat gradient, the cell characteristics and the energy storage device characteristics.

Furthermore, in an exemplary embodiment of the vehicle's energy storage device casing [100], the dimension of the plurality of fins towards the steering side wall of the battery casing [100] is smaller than the dimension of the plurality of fins towards its opposite side wall.

The casing [100] is thus, provided not only to minimise the heat accumulation inside the casing [100] with the help of variable sized ribs but also effectively dissipate the heat out of the casing [100] with the help of variable sized fins.

However, a person skilled in the art may be cognizant of the fact that the arrangement, mounting, connections and positions of the ribs and fins in the casing may vary with respect to maximum desired efficiency of the vehicle, the charging unit, the motor, the control system, etc. Although the present invention has been described in considerable detail with reference to certain preferred embodiments and examples thereof, other embodiments and equivalents are possible. Even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with functional and procedural details, the disclosure is illustrative only, and changes may be made in detail, especially in terms of the procedural steps within the principles of the invention to the full extent indicated by the broad general meaning of the terms. Thus, various modifications are possible of the presently disclosed system and process without deviating from the intended scope and spirit of the present invention. Accordingly, in one embodiment, such modifications of the presently disclosed system and method are included in the scope of the present invention.

Claims

We Claim:

1. A casing [100] for an energy storage device, comprising:

- an inner portion [104] comprising: a plurality of ribs of variable dimension extending from at least one first surface to at least one second surface, wherein the at least one first surface and the at least one second surface are present inside the inner portion [104] of the casing [100]; and a plurality of cells supported by the plurality of ribs.

2. The casing [100] as claimed in claim 1, wherein the variable dimension may comprise at least one of angular dimension, spherical dimension, height, length, width and thickness.

3. The casing [100] as claimed in claim 1, wherein the variable dimension may be based upon at least one of heat gradient, cell characteristics and energy storage device characteristics.

4. A casing [100] for an energy storage device, comprising:

- an inner portion comprising: a plurality of ribs of variable density extending from at least one first surface to at least one second surface, wherein the at least one first surface and the at least one second surface are present inside the inner portion [104] of the casing [100]; and a plurality of cells supported by the plurality of ribs.

5. The casing [100] as claimed in claim 4, wherein the variable density may be based upon at least one of heat gradient, cell characteristics, energy storage device characteristics and dissipation of heat.

6. The casing [100] as claimed in claims 1 and 4, wherein the plurality of ribs may have a non-linear structure to facilitate heat transfer.

7. The casing [100] as claimed in claims 1 and 4, wherein the plurality of ribs may be spatially arranged in the casing [100].

8. A casing [100] for an energy storage device comprising of an outer portion [102] having a plurality of fins, wherein the plurality of fins have variable density.

9. The casing [100] as claimed in claim 8, wherein the variable density may be based upon at least one of heat gradient, cell characteristics, energy storage device characteristics and dissipation of heat.

10. The casing [100] as claimed in claim 8, wherein the plurality of fins may have variable dimension and the dimension may comprise at least one of angular dimension, spherical dimension, height, length, width and thickness.

11. The casing [100] as claimed in claims 1, 4 and 8, wherein the casing [100] may further comprise at least one of cooling fans, cell spacers and thermal conducting material.

12. The casing [100] as claimed in claims 1, 4 and 8, wherein the plurality of cells may be placed on the cell spacers and are supported by the plurality of ribs.