DESC:TECHNICAL FIELD
[0001] The present subject matter relates generally to a power source. More particularly but not exclusively the present subject matter relates to a power source module.
BACKGROUND
[0002] Rechargeable Batteries for example lithium-ion batteries and lead acid batteries are commonly used in portable electronics and in many automobile applications. Due to better power efficiency and life expectancy, lithium-ion batteries are preferred for said portable electronics and in many automobile applications. In automobile industry, the lithium-ion batteries are used for fulfilling power requirements for electrical components and for assisting in engine cranking operation. In addition, now-a-days, lithium-ion batteries are widely used in automobile sector to provide traction power to an electric or hybrid electric vehicles.
[0003] The lithium-ion battery includes a number of lithium-ion cells. Each lithium-ion cell includes an anode, a cathode and a separator submerged in an electrolyte. The separator separates the anode and the cathode but permits the lithium ions to pass through it. Multiple lithium-ion cells are placed in a cell holder which is further enclosed in a housing. The housing as well as the cell holder of the battery pack is generally made of a thermoplastic material.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The details are described with reference to an embodiment of a power source module along with the accompanying diagrams. The same numbers are used throughout the drawings to reference similar features and components.
[0005] Figure 1 exemplarily illustrates an exploded view of a power source module.
[0006] Figure 2(a) exemplarily illustrates a top view of the top holder of one or more cell holder along with the interconnectors.
[0007] Figure 2(b) exemplarily illustrates a bottom view of the bottom holder of one or more cell holder along with the interconnectors.
[0008] Figure 3(a) exemplarily illustrates a top view of the cell modules and a magnified view of single cell receiving means.
[0009] Figure 3(b) exemplarily illustrates a top view of the top holder with the provisions to accommodate the one or more cells and the one or more interconnectors.
[00010] Figure 3(c) exemplarily illustrates a top view of the bottom holder with the provisions to accommodate the one or more cells.
[00011] Figure 4(a) exemplarily illustrates a magnified top view of the interconnector and one or more cells.
[00012] Figure 4(b) exemplarily illustrates an exploded perspective view of the dual row interconnector.
[00013] Figure 4(c) exemplarily illustrates a single row interconnector.
[00014] Figure 5 exemplarily illustrates a side view of a part of the interconnector and a magnified view of the same part.

DETAILED DESCRIPTION

[0001] Generally, the batteries are made up of three units nested inside one another. The three units are one or more cells, a module in which the one or more cells are housed, and one or more interconnector. The three units together housed in a casing forms a battery pack. The one or more cells contains the chemical energy which is converted into electrical energy by a reaction, to provide power to a vehicle or any other component to which it is connected. The one or more cells are grouped into different modules to finally form a battery pack. Apart from this, the interconnector and a busbar are utilized to form an electrical connection between the cells and for collecting the electrical energy from the battery pack for further processing. Batteries using Lithium-ion technology are known for being unstable and highly inflammable, which poses numerous safety problems. There are three main factors that can lead to battery failure : 1) violent shocks, 2) excessive temperatures, and 3) internal short circuits.
[0002] To overcome the above-mentioned problems, the battery pack is provided with an external sleeve between the different polarities of the cell within the module. The sleeves are used for insulation purpose to avoid short circuit, thermal runaway, and the like. In one of the battery configurations, where the sleeves are provided for insulation purpose, a flat interconnector is used to establish the electrical connection between different cells. In other known battery configurations, having higher number of cells, a sleeve is not provided due to complexity in assembly. In above-mentioned configuration, a flat interconnect for making the electrical connection is not suitable. As there is a high probability of a cell holder fouling with the flat interconnector due to the absence of the PVC insulation protective sheet around the cells. With the flat interconnector, there is a huge risk that the interconnector may come in contact with the other parts of the one or more cell, leading to short circuit of the module.
[0003] Conventionally, cell connections (for example: welded wires, strips or lugs) are susceptible to failure when the cells even slightly dislocate during operation, for example, due to the vibration of a moving vehicle. Also, an electrical connection between the cells and the interconnectors should be such that it can handle high current, also the impact of the clearance and creepage distance for the electrical insulation is very significant. The connections between the cells and the busbar are very crucial and thus the contact resistance between the cells and the busbar should be minimum to reduce electrical loss that also generates heat at connection points along the busbar, which is not desirable. In addition to this, cooling of these battery pack is difficult to achieve due to poor thermal management. Thus, there is a need to overcome the above-mentioned problems and other problems of known art.
[0004] An objective of the present subject matter is to provide for a mechanism which facilitates in avoiding short circuit of the battery pack and aids in enhanced thermal management. The present invention also ensures that there is no fouling of interconnector with the cell holder of the battery pack. The present subject matter is described using an exemplary battery pack used in the vehicle, whereas the claimed subject matter can be used in any other type of application employing above-mentioned battery pack, with required changes and without deviating from the scope of invention.
[0005] As per an aspect of the present subject matter, a power source module comprising one or more cells and one or more cell holder, the one or more cell holder includes one or more cell receiving means and one or more interconnector receiving means. The one or more cell holder is configured to receive the one or more cells in one or more cell receiving means. The one or more cell holder is configured to receive one or more interconnectors in the one or more interconnector receiving means.
[0006] As per an aspect of the present subject matter, the one or more cell holder comprising a top holder and a bottom holder.
[0007] As per an aspect of the present subject matter, the one or more cell receiving means is configured to arrest the one or more cells in a fixed position. The cell holder comprising one or more circular grooves on a flat surface configured to receive to accommodate the one or more cell receiving means such that a topmost portion of the one or more cell receiving means is disposed lower than the flat surface of the one or more cell holder.
[0008] As per an aspect of the present subject matter, the one or more cell receiving means is circular in shape integrated with the one or more circular groove. The one or more cell receiving means includes a connecting portion at the centre having a circled portion to accommodate the one or more cell. The circled portion includes a slit for facilitating connection between the one or more cells and the one or more connecting means. The one or more cell receiving means includes one or more vents.
[0009] As per an aspect of the present subject matter, the interconnector receiving means of the cell holder having a first surface disposed lower than the flat surface of the cell holder such that the one or more interconnectors is accommodated within the one or more interconnector receiving means.
[00010] As per an aspect of the present subject matter, the one or more interconnector comprising one or more interconnector plates and a busbar. The one or more interconnector plates includes a channel being capable of receiving a fire-resistant material.
[00011] As per another aspect of the present subject matter, a cell terminal of each of the one or more cells accommodated in the one or more cell receiving means being electrically connected to the busbar of the one or more interconnectors through the one or more connecting means.
[00012] As per another aspect of the present subject matter, the connecting means comprises a head portion and a tail portion, the tail portion configured to connect with the busbar and the head portion is configured to connect with the cell terminal to electrically couple the one or more cells and the one or more interconnectors.
[00013] As per an aspect of the present subject matter, the tail portion is configured to form a curved shape.
[00014] As per an aspect of the present subject matter, the tail portion is configured to form L-shape.
[00015] As per an aspect of the present subject matter, the one or more interconnector being a dual row and a single row.
[00016] As per an aspect of the present subject matter, the interconnector being a power interconnector and a signal interconnector. The embodiments of the present invention will now be described in detail with reference to a power source module along with the accompanying drawings. However, the present invention is not limited to the present embodiments. The present subject matter is further described with reference to accompanying figures. It should be noted that the description and figures merely illustrate principles of the present subject matter. Various arrangements may be devised that, although not explicitly described or shown herein, encompass the principles of the present subject matter. Moreover, all statements herein reciting principles, aspects, and examples of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.
[00017] Fig.1 exemplarily illustrates an exploded view of a power source module 100. The power source module 100 includes one or more cells 102, one or more cell modules 104, one or more cell holder 106, one or more interconnectors 108, and one or more interconnector receiving means 110 (shown in fig.3(b)). The one or more cells 102 provides the electric energy to drive a vehicle (not shown). In the present embodiment, the one or more holder 106 includes a top holder 106a and a bottom holder 106b. The top holder 106a supports a top portion of the one or more cells 102. The bottom holder 106b supports a bottom portion of the one or more cells 102. The one or more cell holders 106 are used to hold the one or more cells 102 in a fixed position, so that required cell arrangement and cell spacing can be maintained. The top holder 106a and bottom holder 106b includes provisions for one or more interconnector receiving means 110 (shown in fig.3(b)) in which the one or more interconnectors 108 are housed. The one or more interconnectors 108 are used to make electrical connection between the one or more cells 102.
[00018] Fig.2(a) exemplarily illustrates a top view of the top holder 106a of the one or more cell holder 106 along with the interconnectors 108 (shown in fig.1) and Fig.2(b) exemplarily illustrates a bottom view of the bottom holder 106b of the one or more cell holder 106 along with the interconnectors 108. Fig.2(a) and Fig.2(b) shall be discussed together. In the present embodiment, the top holder 106a is provided with three rows of cell modules 104 (shown in fig.1) whereas the bottom holder 106b is provided with two rows of cell modules 104 (shown in fig.1). The second row of the top holder 106a is a dual row and both the rows of the bottom holder 106b forms dual row of cells 102. This configuration depends upon the power requirement and application of the power source module 100 (shown in fig.1). So, the number of rows of cell modules 104 (shown in fig.1) and its arrangement can vary accordingly. The first and third row of the cell modules 104 (shown in fig.1) of the top holder 106a is a power interconnector which draws currents as well as voltages/signals. The second or the middle row of the cell modules 104 of the top holder 106a is a signal interconnector which only measures the voltage across the cell modules. Similarly, the two rows of the cell modules 104 of the bottom holder 106b are a signal/voltage interconnector. In the present embodiment, the power interconnector 112 formed as a dual row and the signal interconnector 114 formed as a single row.
[00019] Fig.3(a) exemplarily illustrates a top view of the cell modules 104 and a magnified view of a cell receiving means 116. The cell receiving means 116 is integrally formed in the top holder 106a and the bottom holder 106b (shown in fig.2(b)) of the power source module 100. Each cell 102 is disposed in the cell receiving means 116 which is configured to form a stopper for the one or more cells 102. The cell receiving means 116 facilitates connection of the interconnector 108 with the required terminal only (either positive polarity terminal or negative polarity terminal), and not with any other portion of the cell module 104 (shown in fig.1). Also, the cell receiving means 116 ensures that the one or more cells 102 are disposed in their fixed position and is not vibrating during the vehicle movement. In the present embodiment, as shown in figure 3(a), a connecting means 118 of the one or more interconnector 108 is provided to connect one of the terminals (either positive polarity or negative polarity) of the individual cell 102 with the busbar 120 to form a common connection and to take output out of the power source module 100. The cell receiving means 116 ensures that the one or more interconnector 108 and its connecting means 118 do not touch the cell’s other terminal during assembly as well as during vibration due to the vehicle movement, thus avoiding a potential damage to the one or more cells 102. Thus, the cell receiving means 116 prevents the electrical short circuit between the opposite polarity of one or more cells 102. One or more vents 122 are provided on the one or more cells 102 for cooling of the individual cell 102.
[00020] In the present embodiment, the one or more connecting means 118 is formed as L-shape, connecting two or more cells 102. However, the one or more connecting means 118 can be a curved or a wavy shape, and the like, which do not allow the interconnector 108 to be in any type of contact to the surface of the cells 102 or top holder 106a other than a connecting portion 124 of the one or more cells 102. The one or more connecting means 118 comprises a head portion 118a and a tail portion 118b, the tail portion 118b is configured to electrically connect the head portion 118a to the busbar 120. The tail portion 118b is configured to connect with the busbar 120 and the head portion 118a is configured to connect with the cell terminal to electrically couple the one or more cells 102 and the one or more interconnectors 108. The tail portion 118b being configured to form a L-shaped. This curved shape helps the connecting means 118 to stay away from all the surfaces of the one or more cells 102 and only to be attached to the welding portion of the cell 102. However, the tail portion 118b can be formed to have any type of curved shape. The one or more interconnector 108 electrically connects the one or more cell 102 through a permanent means. In the present embodiment, the permanent means is spot welding. The connecting means 118 is spot welded with the connecting portion 124 of the one or more cells 102. However, any other means of welding can be employed as per the design requirement of the power source module 100 (shown in fig.1). The connecting portion 124 includes a circled portion 124a having a slit 126 to facilitate welding as well as ease of flow of current through it, while in operation. The connecting means 118 is welded on to the connecting portion 124 only and does not comes in contact with any other portion of the one or more cells 102. Fig.3(b) exemplarily illustrates a top view of the top holder 106a with the provisions to accommodate the one or more cells 102 and the one or more interconnectors 108 (shown in fig.3(a)). Fig.3(c) exemplarily illustrates a top view of the bottom holder 106b with the provisions to accommodate the one or more cells 102. Fig.3(b) and Fig.3(c) shall be discussed together. The top holder 106a is provided with one or more grooves 128 to accommodate the one or more cells 102 and the one or more interconnector receiving means 110 are provided to accommodate the one or more interconnectors 108. The one or more cell receiving means 116 are configured to be disposed at a lower position to the one or more cell holder 106 inside the one or more grooves 128. In other word, the one or more cell receiving means 116 is disposed such that a topmost portion of the one or more cell receiving means 116 is disposed lower than a flat surface(S) 138 of the one or more cell holder 106. The one or more grooves 128 are disposed at a particular distance to ensure safety and proper insulation of the one or more cells 102 from each other. The bottom holder 106b receives a bottom portion of the one or more cells 102 in one or more cavity 136 and the one or more interconnectors 108 (not shown in bottom holder) are placed at the rear side of the bottom holder 106b in the one or more interconnector receiving means 110 to form the electrical connection. In the present embodiment, the interconnectors 108 (shown in fig.3(a)) are placed on both the sides of the cell modules 104 and welding is done at both the top holder 106a and at the bottom holder 106b. However, the present invention is also applicable on interconnectors having connections on one side and thus welded on single side only. The one or more grooves 128 is circular in shape and is a through hole, through which the one or more cells is fitted inside the one or more cell receiving means 116 integrated with the cell holder 106.
[00021] Fig.4(a) exemplarily illustrates a magnified top view of the interconnector 108 and one or more cells 102. Fig.4(b) exemplarily illustrates an exploded perspective view of the dual row interconnector 108. Fig.4(c) exemplarily illustrates a single row interconnector 108. Fig.4(a), Fig.4(b), and Fig.4(c) shall be discussed together. The dual row interconnector 108 has one or more cells 102 on both sides of an interconnector plate 130 whereas single row interconnector 108 has one or more cells 102 at one side of the interconnector plate 130. In the best embodiment, a copper plate is combined with a nickel plate to form the signal interconnector 114 (shown in fig.2(a)) or the power interconnector 112 (shown in fig.2(a)). However, the composition of material depends on the power and design requirement of the power source module 100 (shown in fig.1) and thus may vary accordingly. The end of the copper plate 130 is provided with a bent 132 to facilitate the welding of the two plates 130, namely copper and nickel plate, and also to take out the terminals for measurement or connection purpose. The interconnector 108 is provided with the busbar 120 to form a common connection between the cells 102 and to provide a single connection at the end point while taking output from individual cells 102. Mechanically, the busbars 120 for the power source module 100 of electric vehicle or hybrid electric vehicle must be durable, capable of withstanding high levels of vibration while simultaneously providing rigidity to keep the integrity of the power source module 100 while also being flexible enough to cope with elastic, thermal and G-forces. The busbar 120 also assists in thermal management. The busbar 120 minimizes the contact resistance so as to reduce electrical loss that generates heat at connection points along the busbar 120.
[00022] Fig.5 exemplarily illustrates a side view of a part of the interconnector 108 and a magnified view of the same part. The interconnector plates 130 are provided with a channel 134 at the center, along the entire length of the interconnector 108. The channel 134 is filled with a gap filling material for effective thermal management. The channel 134 being capable of receiving a fire-resistant material. The channel 134 formed can be a straight line or can be formed in a wavy pattern. In the present embodiment, a phase changing material is filled in the channel 134. This phase changing material expands with rise in temperature, thus facilitating in cooling. In another embodiment, the interconnector 108 along with the channel may be positioned below the connecting means 118. Many other improvements and modifications may be incorporated herein without deviating from the scope of the invention.

List of Reference numerals
100: Power source module
102: One or more cells
104: One or more cell modules
106: One or more cell holder
106(a): Top holder
106(b): Bottom holder
108: One or more interconnectors
110: One or more interconnector receiving means
112: Power interconnector
114: Signal interconnector
116: Cell receiving means
118: Connecting means
118a: Head portion
118b: Tail portion
120: Busbar
122: One or more vents
124: Connecting portion
124a: Circled portion
126: Slit
128: One or more circular grooves
130: Interconnector plate
132: Bent
134: Channel
136: Cavity
138: Flat surface (S) of 106a
,CLAIMS:We claim:
1. A power source module (100) comprising:
one or more cells (102);
one or more cell holder (106), the one or more cell holder (106) including one or more cell receiving means (116) and one or more interconnector receiving means (110);
wherein, the one or more cell holder (106) being configured to receive the one or more cells (102) in one or more cell receiving means (116); and
the one or more cell holder (106) being configured to receive one or more interconnectors (108) in the one or more interconnector receiving means (110).

2. The power source module (100) as claimed in claim 1, wherein the one or more cell holder (106) comprising a top holder (106a) and a bottom holder (106b).
3. The power source module (100) as claimed in claim 1, wherein the one or more cell receiving means (116) being configured to arrest the one or more cells (102) in a fixed position.
4. The power source module (100) as claimed in claim 1, wherein the cell holder (106) comprising one or more circular grooves (128) on a flat surface (138) configured to receive to accommodate the one or more cell receiving means (116) such that a topmost portion of the one or more cell receiving means (116) being disposed lower than the flat surface (138) of the one or more cell holder (106).
5. The power source module (100) as claimed in claim 1, wherein the one or more cell receiving means (116) being circular in shape and being integrated with the one or more circular groove (128).
6. The power source module (100) as claimed in claim 5, wherein the one or more cell receiving means (116) includes a connecting portion (124) at the centre having a circled portion (124a) to accommodate the one or more cell (102).
7. The power source module (100) as claimed in claim 6, wherein the circled portion (124) includes a slit (126) for facilitating connection between the one or more cells (102) and the one or more connecting means (118).
8. The power source module (100) as claimed in claim 6, wherein one or more cell receiving means (116) includes one or more vents (122).
9. The power source module (100) as claimed in claim 4, wherein the interconnector receiving means (110) of the cell holder (106) having a first surface disposed lower than the flat surface (138) of the cell holder (106) such that the one or more interconnectors (108) being accommodated within the one or more interconnector receiving means (110).
10. The power source module (100) as claimed in claim 1, wherein the one or more interconnectors (108) comprising one or more interconnector plates (130) and a busbar (120), wherein the one or more interconnector plates (130) includes a channel (134) being capable of receiving a fire-resistant material.
11. The power source module (100) as claimed in claim 6, wherein a cell terminal of each of the one or more cells (102) accommodated in the one or more cell receiving means (116) being electrically connected to the busbar (120) of the one or more interconnectors (108) through the one or more connecting means (118).
12. The power source module (100) as claimed in claim 7, wherein the connecting means (118) comprises a head portion (118a) and a tail portion (118b), the tail portion (118b) being configured to connect with the busbar (120) and the head portion (118a) being configured to connect with the cell terminal to electrically couple the one or more cells (102) and the one or more interconnectors (108).
13. The power source module (100) as claimed in claim 12, wherein the tail portion (118b) being configured to form a curved shape.
14. The power source module (100) as claimed in claim 12, wherein the tail portion (118b) being configured to form L-shape.
15. The power source module (100) as claimed in claim 1, wherein the one or more interconnector (108) being a dual row (112) and a single row (114).
16. The power source module (100) as claimed in claim 1, wherein the interconnector (108) being a power interconnector (112) and a signal interconnector (114).