Description:TECHNICAL FIELD
[0001] The present subject matter relates generally to a power source module. More particularly but not exclusively the present subject matter relates to intrinsic construction of the power source module.
BACKGROUND
[0002] Nowadays, with the advancement in the technology, an electric or hybrid electric vehicle make use of one or more power source to drive the vehicle. The one or more powers source is a battery to provide power to run a motor which in turn runs one or more wheels of the vehicle. The battery pack includes one or more cells and are connected through one or more interconnectors to provide an electrical connection. The one or more cells are arranged in a module consisting of a top casing and a bottom casing. The one or more cells are welded to a metal strip known as the interconnector, forming a battery pack. The one or more interconnectors are connected to a BMS (Battery management system).

BRIEF DESCRIPTION OF THE DRAWINGS

[0003] 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.
[0004] Figure 1 exemplarily illustrates an exploded side view of a power source module with a power source module casing.
[0005] Figure 2 illustrates a top isometric view of an interconnector of the power source module.
[0006] Figure 3 illustrates a top perspective view of an interconnector when assembled in the power source module.
[0007] Figure 4 illustrates a top detailed view of an interconnector.

DETAILED DESCRIPTION

[0001] The battery packs are having cells connected in series and parallel configuration depending upon the energy required for the vehicle. These cells are connected to each other using interconnectors that are spot welded on each cell terminal therefore helping in carrying the current from each cell. The battery pack comprises plurality of cells placed adjacent to each other and closely packed inside the battery pack to achieve compact packaging. For distribution of the current in the entire battery, therefore in case of any electrical shock, high currents and abrupt fluctuations in the current are passed on to all the plurality of cells in the battery modules. The plurality of cells may malfunction and go into thermal runaway leading to fire in the battery pack as the current would be dumped on the abused cells. Currently, the conventional battery packs don’t have any provision to disconnect any specific cell in case of electrical abuse on the interconnector. The situation being detrimental to the life of the vehicle and also to the users as fire incidents may occur as a result of thermal runaway.
[0002] Conventionally, one or more interconnectors as an entire single entity is permanently attached to plurality of cells or modules in a battery pack. The attachment process varies between types of cells. Usually, spot welding is used to connect the one or more interconnectors to the one or more cells or the one or more modules in the battery pack.
[0003] One of the known techniques, the technique of Laser welding is difficult as compared to projection welding. Laser welding is expensive, and more surface area is required. Laser welding is mostly preferable for prismatic cells and not for cylindrical cells.
[0004] Further, in a known art, the interconnectors include an L bend, a nickel part is present between the interconnect sheets. However, they don’t fuse whenever higher currents pass through, the L bend just allows the higher currents to reach the entire module.
[0005] However, a need to isolate each cell from one another in the module is necessary so that high currents or abrupt fluctuations do not pass on to the entire module and cause malfunction of the entire system.
[0006] The solution proposed is a new design comprising one or more plates of nickel connectors that are connected by an aluminium or nickel wire bond. The wire bond between the two plates of interconnectors is ultrasonic bonded or laser welded to the both the nickel plates.
[0007] As per an embodiment of the present invention, the invention is a power unit comprising one or more cells, one or more modules comprising the one or more cells, and one or more interconnectors, said one or more interconnectors for electrically connecting said one or more cells.
[0008] As per an embodiment of the present invention, each of the one or more interconnectors includes one or more first interconnectors and one or more second interconnectors.
[0009] As per an embodiment of the present invention, the one or more first interconnectors being configured to be connected to the one or more second interconnectors through wire bond.
[00010] As per an embodiment of the present invention, the wire bond being a fusing element, said wire bond being configured to melt and disconnect said one or more first interconnectors with said one or more second interconnectors during passage of higher currents and passage of abrupt fluctuation in currents.
[00011] As per an embodiment of the present invention, the interconnectors can being made of a metal selected from a group of metals comprising aluminium, nickel, and copper.
[00012] As per an embodiment of the present invention, the wire bond being an aluminium metal.
[00013] As per an embodiment of the present invention, the wire bond connection between one or more first interconnectors and said one or more second interconnectors being achieved through a process of ultrasound bonding.
[00014] As per an embodiment of the present invention, the one or more second interconnectors have smaller surface area as compared to one or more first interconnectors.
[00015] As per an embodiment of the present invention, the one or more second interconnectors being connected to the each of one or more cells through projection welding process.
[00016] Further, the one or more interconnectors being projection welded to the one or more cells. The wire bond being functioning as a fuse over each cell.
[00017] The small interconnect is wire bonded with bigger interconnect and this interconnect plate is projection welded through four holes on the small interconnect.
[00018] Wire bonding is ultrasonic wire bonding, due to ultra-sonic method, welding on cell and interconnect is done. But however, wire bonding requires higher accuracy and process control is high.
[00019] As per an embodiment of the present invention, an ultrasonic wire bonding will connect bigger nickel interconnect and smaller nickel interconnect and the interconnect is projection welded upon the cell.
[00020] So, on each individual cell, the wire bonding fuse is provided, as a safety purpose.
[00021] 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.
[00022] Figure 1 exemplarily illustrates an exploded side view of a power source module 100 with a power source module casing 105. The power source module casing 105 protects the power source module 100 from outside environment and prevents it’s from getting damage. The power source module 100 includes one or more cells (not shown) disposed in one or more holder 104 to hold it still in its required position, during the operation of the vehicle (not shown) and also to maintain the required cell arrangement and cell spacing. The power source module 100 includes the one or more cells (not shown), one or more cell holder 104, and one or more interconnectors 101. The one or more cells 103 provides the electric energy to drive a vehicle (not shown). In the present embodiment, the power source module casing 102 includes a first casing 105a (shown in fig.3), a second casing 105b (shown in fig.3), and a top casing 102. The first casing 105a supports a front portion of the one or more cells. The second casing 105b supports a back portion of the one or more cells. The top casing 102 covers the power source module 100 from a top portion of the power source module 100.
[00023] In an embodiment, the one or more casing can be one of the aluminum casings. The one or more cell holder 104 includes provisions (not shown) for one or more interconnector 101 to be housed. The one or more interconnectors 101 are used to make electrical connection between the one or more cells. The one or more cells 103 are welded to the interconnector 101 to form a power source module 100. The one or more interconnectors 101 are placed above the module 100 and provisions are provided on the module 100 to hold the one or more interconnectors 101 in place.
[00024] Figure 2 illustrates a top isometric view of an interconnector of the power source module. As per an embodiment of the present invention, the one or more interconnectors 101 includes a first interconnector 101a and a plurality of second interconnectors 101b. Wherein, the surface area of the one or more second interconnectors 101b being smaller than the surface area of the one or more first interconnectors 101a. The one or more interconnectors 101 being attached to the one or more cells through projection welding between the one or more second interconnectors 101b and the one or more cells.
[00025] The functionality to be achieved being, the one or more second interconnectors to be wire bonded to the one or more first interconnectors. The wire bonding being made of aluminium material, such that whenever higher currents are passing through the connection made of wire bonding, the connection between the one or more first interconnectors and the one or more second interconnectors melts and the connection between them is disconnected such that the wire bonding functions as a fuse for each cell in the module. Thereby, preventing malfunction of the entire module due to a single faulty cell. Therefore, through the present invention, a safe, efficient system is obtained that is not detrimental to the battery case and entire module.
[00026] Figure 3 illustrates a top perspective view of an interconnector when assembled in the power source module. The power source module 100 depicts the one or more interconnectors 101 in assembled condition with the battery module. The wire bonding 106 being connection between the one or more first interconnectors 101a and the one or more second interconnectors 101b.
[00027] Figure 4 illustrates a top detailed view of an interconnector. As per an embodiment of the present invention, the one or more second interconnectors 101b comprising one or more holes 201 that enable connection between the one or more cells and the one or more second interconnectors 101b.
[00028] Many other improvements and modifications may be incorporated herein without deviating from the scope of the invention.

List of Reference numerals
100: Power unit
105(a): First casing
105(b): Second casing
102: Top casing
103: cell holder
104: One or more cell holder
101: One or more interconnectors
101(a): one or more first interconnectors
101(b): one or more second interconnectors
201: one or more holes
, Claims:I/We claim:
1. A power unit (100) comprising:
one or more cells (103);
one or more modules (104) comprising said one or more cells (103); and
one or more interconnectors (101), said one or more interconnectors (101) for electrically connecting said one or more cells (103),
wherein, each of said one or more interconnectors (101) includes one or more first interconnectors (101a) and one or more second interconnectors (101b),
2. The power unit (100) as claimed in claim 1, wherein said one or more first interconnectors (101a) being configured to be connected to said one or more second interconnectors (101b) through wire bond (106).
3. The power unit (100) as claimed in claim 1, wherein said wire bond (106) being a fusing element, said wire bond (106) being configured to melt and disconnect said one or more first interconnectors (101a) with said one or more second interconnectors (101b) during passage of higher currents and passage of abrupt fluctuation in currents.
4. The power unit (100) as claimed in claim 1, wherein said one or more interconnectors (101) can being made of a metal selected from a group of metals comprising aluminium, nickel, and copper.
5. The power unit (100) as claimed in claim 2, wherein said wire bond (106) being an aluminium metal.
6. The power unit (100) as claimed in claim 1, wherein said wire bond (106) connection between one or more first interconnectors (101a) and said one or more second interconnectors (101b) being achieved through a process of ultrasound bonding.
7. The power unit (100) as claimed in claim 1, wherein said one or more second interconnectors (101b) have smaller surface area as compared to one or more first interconnectors (101a).
8. The power unit (100) as claimed in claim 1, wherein said one or more second interconnectors (101b) being connected to said each of one or more cells (103) through projection welding process.
9. The power unit (100) as claimed in claim 1, wherein said one or more second interconnectors (101b) includes one or more holes (101b) for carrying out projection welding between said one or more interconnectors (101) and said one or more cells (103).