Description:FORM 2

THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENT RULES, 2003

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
A POWER PATH ASSEMBLY FOR BATTERY PACKS

APPLICANT:
EXPONENT ENERGY PRIVATE LIMITED
An Indian entity having address as:
No.76/2, Site No.16, Khatha No.69, Singasandra Village,
Bengaluru (Bangalore) Urban, BENGALURU,
KARNATAKA 560068

The following specification particularly describes the invention and the manner in which it is to be performed. 
CROSS-REFERENCE TO RELATED APPLICATIONS
The present application is the divisional application of Indian application number 202341023942 filed on 30th March 2024 which claims priority from the Indian provisional patent application, having the application number 202341023942, filed on 30th March 2023, incorporated herein by a reference.
TECHNICAL FIELD
The present disclosure relates to the field of batteries and battery modules. More specifically, the present specification relates to a battery assembly architecture. More particularly, the present disclosure relates to a battery assembly comprising a power path assembly by bonding busbars to a battery pack structure by using thermally conductive, electrically isolating and structural adhesive, which may be used in the context of electric vehicles and providing multiple benefits to the system such as reducing the number of fasteners required, minimizing space requirements, simplifying the battery pack assembly.
BACKGROUND
This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present disclosure that are described or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements in this background section are to be read in this light, and not as admissions of the prior art. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to implementations of the claimed technology.
In the field of battery architecture, a battery pack assembly has a wide range of applications in the automobile industry. Specifically in the electric vehicles (EV) market, battery technology has evolved to a great extent in order to produce safe, green, and efficient electric vehicles. The EV market drives on the motto of an alternative eco-friendly solution to crude the fuel-based automotive industry.
Further, In the field of battery architecture, the battery pack assembly generally includes various components such as a structure part, an electrically conductive component which is responsible for carrying a current and a thermal system which is responsible for cooling any heat-generating elements. The interaction between these systems is complex, involving structural, electrical, and thermal considerations. The structure parts are usually made of metals that need to be electrically isolated from a busbar or the electrically conductive part. Further, the busbars themselves have positive and negative sides that also need to be isolated from each other and the structure part. Further, the thermal system usually needs a low thermal resistance path from the heat generating busbars, and good thermal conductors are usually good electrical conductors, so electrically isolating the busbars from the thermal system is also usually a challenge. Further, in the conventional system, one or more fasteners are used to bind these structural components, electrically conductive components, and the thermal system, wherein these fasteners are typically made of metals. Therefore, the isolation of the metal fasteners from those components of the system is a major challenge. Also, this results in a complicated system design with too many parts, difficult assembly, and an inefficient system with high cost.
The busbars, being the parts of an electrical system generally carrying electricity, thus, need to be kept separate from the other parts of the system. To do this, plastic isolators or epoxy isolators are used to keep them apart, but these can be bulky and difficult to install as they need to be separately fastened to the structural and busbar components. Further, the isolators used for the multiple types of busbars may be made of similar material specifically designed for them or may also need to consider multiple parameters such as account creepage distance, and dielectric breakdown of materials separating them, especially for high voltage applications. Further, conventionally the thermal system is generally kept isolated from the heat generating elements (for ex. Current carrying busbars) by using either thermal pads or thermal pastes. The thermal pads or the thermal pastes are thermally conductive and electrically insulating. The thermal pads and the thermal pastes are usually expensive and difficult to assemble. The thermal pads require compression and hence pressure needs to be applied for good contact and the thermal pastes require spacing to be maintained so that squeeze out doesn’t happen.
Therefore, there exists a need to provide a simplified battery pack assembly, in which various components of the battery pack assembly are desired to be attached in such a way that at least simplifies the system design, reduces the number of fasteners, eases the assembly, and lowers costs without sacrificing efficiency.
SUMMARY
This summary is provided to introduce concepts related to the field of battery assembly architecture comprising a power path assembly and more particularly, a power path assembly having bonding of busbars to a battery pack structure by using thermally conductive, electrically isolating, and structural adhesive. This summary is not intended to identify the essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.
According to an embodiment of the present disclosure, a power path assembly for a battery pack is disclosed. The power path assembly may comprise one or more spacers, one or more adhesive layers, a power path plate, and one or more busbars. Each busbar from one or more busbars may be stacked over another busbar from one or more busbars using one or more spacers in between to form a busbar assembly. Further, each busbar in the busbar assembly may be attached to another busbar using one or more adhesive layers. Furthermore, the busbar assembly may be attached to one side of the power path base plate using one or more adhesive layers.

According to another embodiment of the present invention, a method for assembling a power path of a battery pack is disclosed. The method may involve several steps to ensure the proper construction and functionality of the power path assembly. Firstly, one busbar from one or more busbars may be stacked over another busbar using one or more spacers in between, forming a busbar assembly. Additionally, the method discloses one or more steps for assembling the busbar assembly. The busbar assembly may be assembled by connecting one or more inputs of a negative busbar, from one or more busbars to a negative terminal of each battery module from one or more battery modules. Subsequently, the output of the negative busbar may be connected to an input of a charge contactor to establish a negative charge path. Moreover, the output of the negative busbar may be connected to an input of a discharge contactor, via a shunt, to create a negative discharge path. Further steps in the method for assembling the busbar assembly may involve connecting one or more inputs of a positive busbar, from one or more busbars to a positive terminal of each battery module, from one or more battery modules, via one or more fuses. This ensures the establishment of a positive charge path and a positive discharge path. Additionally, the outputs of the positive busbar may be connected to one or more positive charge terminals, one or more positive discharge terminals, or a combination thereof. Continuing with the assembly process, the output of the charge contactor may be connected to one or more negative charge terminals of the power path assembly, and the output of the discharge contactor may be linked to one or more negative discharge terminals through a discharge fuse. Further steps for assembling the power path of the battery pack may involve attaching one busbar of the busbar assembly to another busbar using one or more adhesive layers. Additionally, the busbar assembly may be affixed to one side of a conditioning plate using one or more adhesive layers, facilitating the conditioning process of the busbar assembly.
The foregoing summary is illustrative only and is not intended to be in any way limiting. 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
The detailed description is described with reference to the accompanying Figures. In the Figures, the left-most digit(s) of a reference number identifies the Figure in which the reference number first appears. The same numbers are used throughout the drawings to refer to features and components.
Figure 1 illustrates an exploded view of a power path assembly (100) for a battery pack, in accordance with an embodiment of the present disclosure.
Figure 2a illustrates a top view of the power path assembly (100) in accordance with the embodiment of the present disclosure.
Figure 2b illustrates a side view of the power path assembly (100) in accordance with the embodiment of the present disclosure.
Figure 2c illustrates a perspective view of the power path assembly (100) in accordance with the embodiment of the present disclosure.
Figure 3 illustrates a block diagram describing a three-layer architecture of the power path assembly (100) in accordance with the embodiment of the present disclosure.
Figure 4 illustrates a method (400) for assembling a power path of a battery pack, in accordance with the embodiment of the present disclosure.
It should be noted that the accompanying figures are intended to present illustrations of exemplary embodiments of the present disclosure. These figures are not intended to limit the scope of the present disclosure. It should also be noted that accompanying figures are not necessarily drawn to scale.
DETAILED DESCRIPTION
The terms “comprise”, “comprising”, “include(s)”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a setup, system, or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such setup or system or method. In other words, one or more elements in a system or apparatus preceded by “comprises… a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.
Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment,” or “in an embodiment” in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
In the various embodiments disclosed herein, ‘a battery assembly’ may be interchangeably read and/or interpreted as ‘a battery module’, ‘module’ or ‘a battery pack’ ‘an energy storage system’ or ‘an energy storage apparatus’ or the like. Further, ‘an adhesive’ may be interchangeably read and/or interpreted as ‘a glue’ or ‘a sealant’ or the like. A ‘a battery cell’ may further be interchangeably read and/or interpreted as a ‘cell’ or a ‘storage cell’ or an ‘energy storage cell’ or an ‘energy storage device’ or the like.
Referring to Figure 1, an exploded view of a power path assembly (100) for a battery pack is illustrated in accordance with an embodiment of the present disclosure. In an embodiment of the present disclosure, the power path assembly (100) comprise one or more spacers (101), one or more adhesive layers (102), one or more busbars (103, 104, 105), a power path plate (106), one or more conditioning plates (107) and one or more electrical components (108).
In one embodiment, each of the busbar from one or more busbars (103, 104, 105) may be stacked over another busbar, from the same set or from one or more other sets of busbars (103, 104, 105), utilizing one or more spacers (101) positioned in between, thereby forming a busbar assembly (201) (as illustrated in Figure 2a). Subsequently, each busbar within the busbar assembly (201) may be attached to another busbar using one or more adhesive layers (102). Further, the busbar assembly (201) may be attached to one side of the power path base plate (106) using one or more adhesive layers (102).
In an exemplary embodiment, a first busbar (103), from one or more busbars (103, 104, 105), may be attached to a second busbar (104), from one or more busbars (103, 104, 105), through an adhesive (102) by using one or more spacers (101) in between to form an intermediate busbar assembly. Further, a third busbar (105), from one or more busbars (103, 104, 105), may be attached to the intermediate busbar assembly, through an adhesive (102) by using one or more spacers (101) in between to form the busbar assembly (201). In another embodiment, a method for assembling a power path assembly within a battery pack is disclosed. In one embodiment, a first busbar (103) selected from one or more busbars (103, 104, 105) may be securely attached to a second busbar (104), also chosen from the same or another busbars (103, 104, 105). This attachment process may involve the application of an adhesive (102) between the two busbars, facilitated by one or more spacers (101) positioned in between, thereby forming an intermediate busbar assembly.
In another embodiment, after the formation of the intermediate busbar assembly (201), a third busbar (105) from the same or other busbars (103, 104, 105) may be affixed to the existing assembly. Similar to the previous step, adhesive (102) may be applied between the third busbar and the intermediate assembly, with one or more spacers (101) utilized to ensure proper alignment and spacing between the components. This process results in the completion of the busbar assembly (201), comprising multiple busbars securely bonded together by adhesive layers (102) and spaced apart by one or more spacers (101).
In yet one embodiment, the adhesive (102) may comprise a thermally conductive, electrically isolating, structural adhesive. In a related embodiment, the adhesive (102) may correspond to Polyurethane acrylate adhesive. In one embodiment the busbar assembly (201) may be mounted on the power path plate (106), mounted on the battery module, using the adhesive (102). In another embodiment, the busbar assembly (201) may be attached to a conditioning plate (107), using the adhesive. Direct attachment to the conditioning plate (107) facilitates thermal conditioning of the busbar assembly (201) using conditioning fluid passes through one or more conditioning channels in the conditioning plate (107). In another embodiment, the busbar assembly (201) may be mounted on the power path base plate (106) using the adhesive (102), and the power path base plate (106) may be attached to the conditioning plate (107) using the adhesive (102). In one embodiment, the attachment of the current carrying busbar assembly (201) either to the conditioning plate (107) directly or to the conditioning plate (107) through the power path base plate (106), through the adhesive, may enable maintaining of electrical isolation between the current carrying busbar assembly (201), the power path base plate (106) and the conditioning plate (107). In another embodiment, the attachment of the current carrying busbar assembly (201) either to the conditioning plate (107) directly or to the conditioning plate (107) through the power path base plate (106), through the adhesive (102), may enable maintaining of thermal conduction between the current carrying busbar assembly (201), the power path base plate (106) and the conditioning plate (107). In one embodiment, a thermal mass may be shared among the plurality of busbars (103, 104, 105), the power path base plate (106) along with the conditioning plate (107). In another embodiment, the attachment of the current carrying busbar assembly (201) either to the conditioning plate (107) directly or to the conditioning plate (107) through the power path base plate (106), through the adhesive (102), may enable the forming a structured combination of the current carrying busbar assembly (201) and the conditioning plate (107). In one embodiment, the plurality of spacers (101) may comprise hard spacers. In one embodiment, each busbar from the one or more busbars (103,104,105) may be attached to each other using the adhesive (102) along with one or more spacers (101), wherein the one or more spacers (101) may be used to maintain a required spacing between the one or more busbars (103,104,105). In one embodiment, the required spacing may be decided based on at least one of but not limited to, the required dielectric breakdown voltage, the thermal conductivity requirement and the structural requirement.
Now referring to Figure 2a, a top view of the power path assembly (100) is illustrated in accordance with the embodiment of the present disclosure. In one embodiment, the busbar assembly (201) may be attached either to the conditioning plate (107) directly or to the conditioning plate (107) through the power path base plate (106), using the adhesive (102) along with the one or more spacers (101). In one embodiment, one or more fasteners may be used to mount one or more serviceable components or the other electrical components (108) on the busbar assembly (201). The one or more fasteners may comprise clinch studs or nuts.
In one embodiment, the conditioning plates (107) may comprise an inlet port, an outlet port, and a plurality of conditioning channels. In one embodiment the inlet port is configured to receive conditioning fluid into the conditioning plate (107) and the outlet port is configured to exit the conditioning fluid from the conditioning plate (107). In one embodiment, the conditioning plate (107) may comprise a plurality of microchannels. The plurality of microchannels may be configured to enable flowing of conditioning fluid inside the conditioning plates (107). In another embodiment, the conditioning plates (107) may comprise serpentine fluid channels. The serpentine fluid channels enable the conditioning fluid in the conditioning plates (107) to flow in a serpentine fluid flow.
In an exemplary embodiment, one or more conditioning plates (107) may comprise a first conditioning plate and a second conditioning plate positioned opposite to one or more battery cells. In one embodiment, the first conditioning plate may be configured to be attached to a first side of the plurality of cells and the second conditioning plate may be configured to be attached to the other side of the plurality of cells, different from the first side. In one embodiment, one or more conditioning plates (107) may comprise a plurality of microchannels, wherein the plurality of microchannels may be configured to enable the flowing of conditioning fluid inside the conditioning plates. In another embodiment, one or more conditioning plates may comprise serpentine fluid channels, wherein the conditioning fluid in the plurality of conditioning plates may flow in a serpentine fluid flow.
Further, the inlet port and the outlet port of the conditioning plate (107) may be connected to a conditioning station, via a fluid connector during charging or conditioning, for flowing the conditioning fluid to the power path assembly (100). In another embodiment, the conditioning fluid may be a cold fluid, or a hot fluid based on the thermal requirements of the power path assembly (100).
According to an embodiment of the present disclosure, a power path assembly (100) of a battery assembly is disclosed. The plurality of battery cells may be arranged in a predefined manner to form a battery module. A plurality of battery modules may further be arranged in a predetermined manner to form a battery pack.
In an exemplary non-limiting embodiment, a power path assembly (100) of a battery pack may be used for charging and discharging the battery pack. In one embodiment, the power path assembly (100) may comprise one or more busbars (103, 104, 105), wherein a first plurality of busbars from the one or more busbars (103, 104, 105) may be used for implementing a charging path, wherein a second plurality of busbars from the one or more busbars (103, 104, 105) may be used for implementing a discharging path. In one embodiment, the one or more busbars (103, 104, 105) may comprise busbars made of aluminium material. In one embodiment, the first plurality of busbars may be attached with the second plurality of busbars using the adhesive (102), to form the busbar assembly (201), wherein the adhesive (102) may comprise a thermally conductive, electrically isolating, structural adhesive. In one embodiment the busbar assembly (201) may be mounted on the power path plate (106), mounted on the battery module, using the adhesive (102). In one another embodiment, the busbar assembly (201) may be attached to a conditioning plate, wherein the conditioning plate (107) may be configured to flow a conditioning fluid inside the conditioning plate (107). In another embodiment, the busbar assembly (201) may be mounted on a power path base plate (106) using the adhesive (102), wherein the power path base plate (106) may be attached to the conditioning plate (107) from the plurality of conditioning plates using the adhesive (102). In one embodiment, the conditioning plate (107) may be configured to provide active conditioning during the charging of the battery pack. In one embodiment, during the charging of the battery pack, the plurality of cells attached to the conditioning plate (107) may be conditioned using the conditioning fluid, wherein the conditioning of the cells may be performed by conduction through the conditioning plate (107).
In another exemplary embodiment, during the charging of the battery pack, the first plurality of busbar attached either to the conditioning plate (107) directly or to the conditioning plate (107) through the power path base plate (106) may be conditioned using the conditioning fluid. In one embodiment, the conditioning plate (107), the power path base plate (106) and the first plurality of busbars may be configured to provide passive conditioning, during discharging of the battery pack. In one embodiment, during the discharging of the battery pack, the second plurality of busbars may be conditioned by the conditioning plate (107), the power path base plate (106) and the first plurality of busbars, attached through the adhesive (102). In another embodiment may comprise one or more adhesive layers (102). Further, the conditioning plate (107) may be attached to attached to one or more battery modules, using one or more adhesive layers (102), for conditioning the one or more battery modules. Further, each battery module from one or more battery modules may comprise one or more cells arranged in a predetermined manner. Further, each battery module from the one or battery modules may comprise a positive terminal and a negative terminal. In one embodiment, the power path assembly (100) may comprise a conditioning plate (107) attached to one or more battery modules using one or more adhesive layers (102) for conditioning one or more battery modules. Further, the conditioning may comprise at least one of temperature conditioning, pressure conditioning, or electrical charging of the busbar assembly, and a combination thereof.
In another embodiment, the adhesive of one or more adhesive layers (102) may comprise at least one of a fast curing, thermally conductive, structural member, or an electrically insulative adhesive, and a combination thereof. Further, adhesive of the one or more adhesive layers (102) may correspond to Polyurethane acrylate adhesive.
In one embodiment, the power path assembly (100) may comprise one or more positive charge terminals, one or more positive discharge terminals, one or more negative charge terminals, one or more negative discharge terminals, a battery management system (BMS), a Printed Circuit Board (PCB). Further, one or more electrical components (108) may comprise one or more busbars, connectors, or other electrical components. The one or more electrical components (108) may comprise, for example, but not limited to fuses, a charge contactor, a discharge contactor and one or more shunts. In one embodiment, each busbar from the one or more busbars may comprise a metal busbar for transmitting an electric current. The one or more electrical components may be attached to the busbar assembly (201) using one or more fastening means. Further, one or more fastening means may comprise, for example, but not limited to clips, clinch studs, nuts, or bolts.
In another embodiment, one or more busbars (103, 104, 105) may comprise a positive busbar and a negative busbar. In another embodiment, one or more inputs of the negative busbar may connect to the negative terminal of each battery module, from one or more battery modules. In another embodiment, one or more outputs of the negative busbar may comprise a negative charge path and a negative discharge path. Further, the negative charge path may correspond to connecting the output of the negative busbar to an input of the charge contactor. In another embodiment, the negative discharge path may correspond to connecting the output of the negative busbar to an input of the discharge contactor through a shunt. Further, one or more inputs of the positive busbar may be connected to the positive terminal of each battery module, from one or more battery modules, through one or more fuses. Further, one or more outputs of the positive busbar are connected to one or more positive charge terminals, one or more positive discharge terminals, or a combination thereof, of the power path assembly (100). Further, one or more outputs of the charge contactor are connected to one or more negative charge terminals of the power path assembly (100). Furthermore, an output of the discharge contactor is connected to the one or more negative discharge terminals of the power path assembly (100), through a discharge fuse from the one or more fuses.
Referring to Figure 2b, a side view of the power path assembly (100) is illustrated in accordance with the embodiment of the present disclosure. Referring to Figure 2c, a perspective view of the power path assembly (100) is illustrated in accordance with the embodiment of the present disclosure.
Referring to Figure 3, a block diagram describing a three-layer architecture of the power path assembly (100) of the battery pack is illustrated in accordance with the embodiment of the present disclosure. The three-layer architecture of the power path assembly (100) may comprise stack 1, stack 2 and stack 3. In one embodiment, the stack 1 may correspond to a bottom layer of one or more busbars attached to the plurality of battery modules of the battery pack. In one embodiment, the stack 1 may be parallelly attached with ground or negative terminals of the plurality of battery modules of the battery pack. The negative terminal of the plurality of battery modules of the battery pack may comprise a plurality of negative charge terminal of the plurality of battery modules. The plurality of negative charge terminal of the plurality of battery modules may form a plurality of negative charge terminal module. Further, the plurality of negative charge terminal module may form a negative busbar if connected to a busbar. In one embodiment, the stack 1 may comprise a negative busbar, wherein the negative busbar may split into a plurality of paths. In one embodiment, a first path from the plurality of paths may comprise a negative charge path built through a charge contactor. In another embodiment, a second path from the plurality of paths may comprise a discharge path built through a shunt, a discharge contactor, and a discharge fuse.
In another embodiment, the positive terminal of the plurality of battery modules of the battery pack may comprise a plurality of positive charge terminal of the plurality of battery modules. The plurality of positive charge terminal of the plurality of battery modules may form a plurality of positive charge terminal module. Further, the plurality of positive charge terminal module may be connected to a positive busbar.
In one embodiment, the stack 2 may be attached to the stack 1 through the adhesive. In one embodiment, the stack 2 may be parallelly attached with positive terminals of the plurality of battery modules of the battery pack. In one embodiment, stack 2 may comprise a positive busbar, wherein the positive busbar may be parallelly attached to the positive terminals of the plurality of battery modules through a plurality of fuses. In one embodiment, the plurality of fuses may be configured to form a positive charge terminal of the battery pack or a positive discharge terminal of the battery pack.
In another embodiment, stack 3 may be attached to the stack 2 through the adhesive. In one embodiment, the stack 3 may be configured to form a negative charge terminal and a negative discharge terminal of the battery pack. In one embodiment, the layer 3 may comprise a charge contactor which is configured to act as an exit of the negative charge terminal. In another embodiment, the stack 3 may comprise a discharge contactor which is configured to act as an exit of the negative discharge terminal connected through a discharge fuse.
In one embodiment, the stack 1 may be placed as a bottom layer attached to the plurality of battery modules of the battery pack and the stack 2 may be placed in the middle and stack 3 may be placed on the top. In another embodiment, the stack 1 may be placed as a bottom layer attached to the plurality of battery modules of the battery pack and the stack 3 may be placed in the middle and stack 2 may be placed on the top. In one embodiment, the stack 2 may be placed as a bottom layer attached to the plurality of battery modules of the battery pack and the stack 1 may be placed in the middle and stack 3 may be placed on the top. In another embodiment, the stack 2 may be placed as a bottom layer attached to the plurality of battery modules of the battery pack and the stack 3 may be placed in the middle and stack 1 may be placed on the top. In one embodiment, the stack 3 may be placed as a bottom layer attached to the plurality of battery modules of the battery pack and the stack 1 may be placed in the middle and stack 2 may be placed on the top. In another embodiment, the stack 3 may be placed as a bottom layer attached to the plurality of battery modules of the battery pack and the stack 2 may be placed in the middle and stack 1 may be placed on the top.
The present invention may allow the downsizing of both the battery pack structure and the busbars, with higher strength/stiffness and current carrying capacity. In an exemplary embodiment, a thermal system may also be connected using the same adhesive, leading to a low thermal resistance conductive path for heat and further downsizing of the busbars and the thermal system. The present invention may also allow for replacing existing thermal systems, to avoid duplication of the thermal system components.
After the busbars and other electrical components have been stacked and spaced appropriately, they may be bonded to the structure of the battery pack using the same thermally conductive, electrically isolating, structural adhesive. This means that the busbars themselves may become part of the structure of the battery pack, adding strength and stiffness to the system.
For example, if the set of three stacks of the busbars with adhesive is used, it may result in a structural material bonded to the battery pack structure. This additional structural material may improve the overall strength and stiffness of the battery pack structure while also acting as a thermal sink to dissipate any heat generated by the busbars. By incorporating the busbars into the structure of the battery pack, it may be possible to downsize both the battery pack structure and the busbars themselves. This is because the stacked assembly may have a higher strength, stiffness, and current-carrying capacity, allowing for a more compact and efficient battery pack design.
Overall, the use of the thermally conductive, electrically isolating, structural adhesive in combination with the stacked busbars may provide a strong, reliable, and efficient solution for building the battery packs with improved thermal management and structural integrity.
In an embodiment of the present disclosure, the conditioning fluid may be any fluid, preferably a liquid. In one exemplary embodiment, the conditioning fluid may either be a cold fluid or a hot fluid, depending on the thermal requirements of the battery. A conditioning station/vehicle charging station may be allowed to flow the conditioning fluid into the battery assembly, via a connector, while performing the conditioning/charging of the battery assembly. Further, the plurality of conditioning plates and the battery cell structure may be fixed by bonding with a thermally uniform conductive structural adhesive/glue. The thermally conductive adhesive may be configured to maintain the electrical isolation from the battery cells, to protect cells during automotive vibrations caused by the road, and to keep the cells under the right operating condition.
The battery assembly acts as a unibody where everything is bonded together ensuring that the complete battery assembly architecture acts as a single unit during an automotive vibration scenario. Such unibody architecture may create better stiffness than a conventional architecture and may use the structural strength of each battery cell as a battery assembly structure.
In a non-limiting embodiment of the present disclosure, the plurality of battery cells may be arranged in a fixture, like the battery module case, or by using the plurality of spacer elements. The plurality of spacer elements may be utilized to ensure an equal spacing between the plurality of battery cells. The fixture may also be configured to ensure equal spacing of the plurality of battery cells via the fixture tolerances.
In another non-limiting embodiment, the thermally conductive and electrically insulative adhesive may be applied to the side faces of each battery cell from the plurality of battery cells. Then, the plurality of conditioning plates may be glued to the side faces of the plurality of battery cells. As soon as the adhesive gets cured, a battery assembly with a structurally bonded plurality of battery cells may be formed. Also, the battery assembly may be formed as a thermally conductive battery assembly. This battery assembly may be configured for maintaining an electrical isolation between the plurality of battery cells and the plurality of conditioning plates.
In an embodiment, the plurality of spacers may form a spacers assembly which may be used between each battery cell and the conditioning plates. The spacers assembly may consist of a plastic sheet bonded with a double-sided tape, which may be either silicone based or acrylic based adhesive. Further, this double-sided tape may be applied to the body of each battery cell. In this case, the thickness of the plastic sheet may be maintained and designed to have multiple isolation values as required by the battery assembly to be manufactured. At least two spacers may be used for each battery cell.
The battery assembly, as disclosed, may comprise a well- maintained electrical isolation between the body of each battery cell and the plurality of conditioning plates. This electrical isolation is consistent across the battery packs of the battery assembly.
Such battery assembly architecture may result in building the battery assembly using a single adhesive. This may also ensure that the battery assembly is thermally stable and structurally effective for any kind of mechanical vibrations. This may further confirm an electrical insulation of the plurality of battery cells from the battery pack or the battery assembly. The mechanical vibrations exerted on the battery assembly may be any mechanical/frictional vibrations while the battery assembly may be used in an automobile.
In an embodiment, the disclosed battery assembly architecture may ensure that the load is equally distributed among the plurality of battery cells. The equal load distribution may be able to create uniform stiffness across the battery assembly.
Now referring to Figure 4 a flowchart describing a method (400) for assembling a power path of a battery pack is illustrated in accordance with an embodiment of the present subject matter is disclosed. The method (400) may involve various steps for assembling a power path of a battery pack.
Further, the method (400) may involve a step (401) for stacking one busbar (103), from one or more busbars (103, 104, 105), over another busbar (104) using one or more spacers (101), in between, to form a busbar assembly (201).
Further, the busbar assembly (201) may be assembled by connecting (401a) one or more inputs of a negative busbar, from one or more busbars to a negative terminal of each battery module, from one or more battery modules.
Further, the method (400) may involve step connecting (401b) the output of the negative busbar to an input of a charge contactor to form a negative charge path.
Further, the method (400) may involve step connecting (401c) output of the negative busbar to an input of a discharge contactor, via a shunt, to form a negative discharge path.
Further, the method (400) may involve step connecting (401d) one or more inputs of a positive busbar, from one or more busbars to a positive terminal of each battery module, from one or more battery modules, via one or more fuses.
Further, the method (400) may involve step connecting (401e) outputs of the positive busbar to one or more positive charge terminals, one or more positive discharge terminals, or a combination thereof.
Further, the method (400) may involve step connecting (401f) an output of the charge contactor to one or more negative charge terminals of the power path assembly.
Further, method (400) may involve a step connecting (401g) an output of the discharge contactor to one or more negative discharge terminals through a discharge fuse.
Further, method (400) may involve a step attaching (402) one busbar (103) of the busbar assembly (201) to another busbar (104) by using one or more adhesive layers (102).
Furthermore, method (400) may involve a step attaching (403) the busbar assembly (201) to one side of a conditioning plate (107) using one or more adhesive layers (102), for conditioning the busbar assembly (201).
The presently disclosed power path assembly (100) comprising the busbar assembly (201) bonded with thermally conductive, electrically isolated, and structural adhesive may have the following advantageous functionalities over the conventional art:
• Providing an optimized busbar assembly with reduced complexity, using only a few assembly parts (such as fasteners), easy assembly and reliability, without sacrificing efficiency.
• Providing optimized busbar assembly with a compact size compatible with applications having space constraints.
• Overall batter structural strength of the battery pack assembly
• Downsizing of the battery pack assembly
• Enabling multiple busbars to stack on top of each other despite their polarity.
• Strategically using spacers for each assembly and reliability
• Adding a three layers of busbars with each having an adhesive layer, a combined structure adds more strength and stiffness to the battery pack assembly.
• Enabling one set of busbar to act as a heat sink for another set of busbars, leading to downsizing of the overall battery assembly.
• Active conditioning of the busbar assembly allowing it to pass high current capacity, enabling the possibility of fast charging application.
• Conditioning of the busbar assembly using the conditioning plate leads to a low thermal resistance conductive path along with electrical isolation.
• Capability of replacing with an existing thermal system, to avoid duplication of thermal system.
• Enabling Active as well as passive conditioning of the power path assembly.
• Reduced weight and size of the battery assembly.
• Easy serviceability of the battery assembly in case of maintenance activity
• The battery assembly is formed as a unibody architecture.
• Provides better structural integrity and stiffness of the battery assembly.
• Compact and concise arrangement in the battery for avoiding poor use of space or storage.
Various modifications to the embodiment will be readily apparent to those skilled in the art and the generic principles herein may be applied to other embodiments. However, one of ordinary skill in the art will readily recognize that the present disclosure is not intended to be limited to the embodiments illustrated but is to be accorded the widest scope consistent with the principles and features described herein.
The foregoing description shall be interpreted as illustrative and not in any limiting sense. A person of ordinary skill in the art would understand that certain modifications could come within the scope of this disclosure.
The embodiments, examples, and alternatives of the preceding paragraphs or the description, including any of their various aspects or respective individual feature(s), may be taken independently or in any combination. Features described in connection with one embodiment are applicable to all embodiments unless such features are incompatible.
 
, Claims:WE CLAIM:
1. A method (400) for assembling a power path of a battery pack, characterized in that, the method (400) comprises:
stacking (401) a busbar (103), from one or more busbars (103, 104, 105), over another busbar (104) using one or more spacers (101) in between, to form a busbar assembly (201), wherein the busbar assembly (201) is assembled by:
connecting (401a) one or more inputs of a negative busbar, from the one or more busbars (103, 104, 105) to a negative terminal of each battery module from one or more battery modules;
connecting (401b) one output of the negative busbar to an input of a charge contactor to form a negative charge path;
connecting (401c) another output of the negative busbar to an input of a discharge contactor, via a shunt, to form a negative discharge path;
connecting (401d) one or more inputs of a positive busbar, from the one or more busbars (103, 104, 105) to a positive terminal of each battery module, from the one or more battery modules, via one or more fuses;
connecting (401e) one or more outputs of the positive busbar to one or more positive charge terminals and a positive discharge terminal, of a power path assembly (100);
connecting (401f) an output of the charge contactor to one or more negative charge terminals of the power path assembly (100); and
connecting (401g) an output of the discharge contactor to a negative discharge terminal, of the power path assembly (100), through a discharge fuse.
attaching (402) the busbar (103) of the busbar assembly (201) to the another busbar (104) by using one or more adhesive layers (102); and
attaching (403) the busbar assembly (201) to one side of a conditioning plate (107) using the one or more adhesive layers (102), for conditioning the busbar assembly (201) using a conditioning fluid.
2. The method (400) as claimed in claim 1, wherein the assembling the power path of the battery pack corresponds to a three-layer architecture, wherein the three-layer architecture comprises a first stack, a second stack and a third stack, wherein the first stack comprises the negative busbar (103), wherein the second stack comprises the positive busbar (104), wherein the third stack comprises one or more electrical components (108) from the one of one or more fuses, the charge contactor, the discharge contactor, the one or more shunts, the discharge fuse and a combination thereof.
3. The method (400) as claimed in claim 2, wherein the first stack corresponds to one of connecting (401a) the one or more inputs of the negative busbar (103) to the negative terminal of each battery module, connecting (401b) the one output of the negative busbar (103) the charge contactor, connecting (401c) the another output of the negative busbar (103) to the input of the discharge contactor via the shunt, and a combination thereof.
4. The method (400) as claimed in claim 2, wherein the second stack corresponds to one of connecting (401d) the one or more inputs of the positive busbar (104) to the positive terminal of each battery module via the one or more fuses, connecting (401e) the one or more outputs of the positive busbar (104) to the one or more positive charge terminals and the positive discharge terminal of the power path assembly (100), and a combination thereof.
5. The method (400) as claimed in claim 2, wherein the third stack corresponds to one of connecting (401f) the output of the charge contactor to the one or more negative charge terminals of the power path assembly (100), connecting (401g) the output of the discharge contactor to the negative discharge terminal, of the power path assembly (100) through the discharge fuse, and a combination thereof.
6. The method (400) as claimed in claim 2, wherein sequence of stacking of the first stack, the second stack, and the third stack is omnidirectional.
7. The method (400) as claimed in claim 1, wherein the conditioning plate (107) is configured to provide active conditioning of the busbar assembly (201) during charging of the battery pack.
8. The method (400) as claimed in claim 1, wherein the conditioning plate (107), a power path base plate (106) and the busbar assembly (201), combined via the one or more adhesive layer (102), is configured to provide passive conditioning of the busbar assembly (201) during discharging of the battery pack.
Dated this 27th day of December 2024


DEEPAK KUNDLIK PAWAR
IN/PA-2052
AGENT FOR THE APPLICANT