FORM2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10, rule 13)
1. Title of the invention: TABLESS ENERGY STORAGE DEVICES
2. Applicant(s)
NAME NATIONALITY ADDRESS
OLA ELECTRIC MOBILITY
LIMITED
Indian Regent Insignia, #414, 3rd Floor, 4th
Block, 17th Main, 100 Feet Road,
Koramangala, Bangalore, Karnataka
560034, India
3. Preamble to the description
COMPLETE SPECIFICATION
The following specification particularly describes the invention and the manner in which it
is to be performed.
1
BACKGROUND
[0001] Energy storage devices, such as cells or batteries, are typically used
in variety of electrical and mechanical devices to power different components of
5 these devices. Generally, such storage devices include an electrode assembly
comprising a cathode electrode, an anode electrode, and a separator
sandwiched between the two along with a conductive layer integrated with the
electrodes. To provide electrical connection between the electrodes and the
external circuit, the conductive layer is crushed and welded to the energy storage
10 device’s lid.
BRIEF DESCRIPTION OF DRAWINGS
[0002] The detailed description is provided with reference to the
accompanying figures, wherein:
15 [0003] FIG. 1 illustrates a front view of a conductive layer of an energy storage
device, in accordance with an example of the present subject matter;
[0004] FIG. 2 illustrates dimensions of various portions of a conductive layer,
in accordance with one example of the present subject matter;
[0005] FIG. 3 illustrates a front view of another example of a conductive layer,
20 in accordance with another example of the present subject matter;
[0006] FIG. 4 illustrates an orthogonal front view of an electrode with a
conductive layer having a pattern formed thereon integrated with the electrode,
in accordance with one example of the present subject matter; and
[0007] FIG. 5 illustrates an exploded view of an energy storage device with a
25 conductive layer having a pattern formed thereon integrated with an electrode
assembly, in accordance with one example of the present subject matter.
[0008] It may be noted that throughout the drawings, identical reference
numbers designate similar, but not necessarily identical, elements. The figures
are not necessarily to scale, and the size of some parts may be exaggerated to
30 more clearly illustrate the example shown. Moreover, the drawings provide
2
examples and/or implementations consistent with the description; however, the
description is not limited to the examples and/or implementations provided in the
drawings.
5 DETAILED DESCRIPTION
[0009] Energy storage devices, particularly lithium-ion batteries, have
become integral components in a wide range of applications, from portable
electronics to electric vehicles and large-scale energy storage systems. These
batteries typically consist of an electrode assembly comprising a cathode, an
10 anode, and a separator sandwiched between the two. Further, a layer of
conductive material may be integrated with electrodes to provide electrical
connections between various internal components of the energy storage device
and an external circuit. In an example, layer which is integrated with the cathode
is usually made of aluminium, while copper is commonly used for the layer which
15 is integrated with the anode. Such types of energy storage devices in which a
conductive layer is integrated throughout the width of the electrode is generally
termed as “tabless” battery. In such batteries, the functions performed by tab in
“strip type tab” battery is performed by the conductive layer.
[0010] In the manufacturing process of these batteries, one of the important
20 steps is the crushing of the integrated conductive layer so that these layers may
get flattened to provide a connection surface, which may act as a current
collector. This step aims to create a dense, uniform connection between the
electrode assembly and a terminal, such as lid, of the energy storage device,
ensuring optimal electrical conductivity and mechanical stability. Conventional
25 methods of crushing such conductive layers often involve applying pressure to
both the cathode and anode layers simultaneously using a single crushing tool or
nob. This approach relies on the mechanical deformation of the conductive layers
to create a compact, flattened area suitable for welding to the lid portion of the
energy storage device.
3
[0011] However, the existing crushing process faces several challenges that
may impact the overall quality and performance of the battery. Due to the different
material properties of aluminum (cathode) and copper (anode) layers,
simultaneous crushing often results in uneven deformation. For example, the
5 softer metal typically deforms more readily, leading to inconsistent current
collector height and potential misalignment. Variations in the crushed layer’s
height may lead to inconsistencies in the overall height of the device, which is
crucial for maintaining uniform pressure within the energy storage device and
ensuring proper fit in battery packs.
10 [0012] Current crushing methods may also create air gaps within the crushed
layer structure, thereby reducing the overall density of the material. This may lead
to poor electrical contact and increased internal resistance. Further, during the
crushing process, the variations in the current collector height may lead to shifting
of electrode assembly due to inadequate gripping, potentially affecting the
15 internal structure and performance of the energy storage device. Improper
crushing may result in a less dense structure, potentially increasing the electrical
resistance and reducing the overall efficiency of the energy storage device. The
current crushing method may create weak points or stress concentrations in the
current collector, potentially leading to mechanical failures over time.
20 [0013] Further, while assembling the energy storage device, the electrode
assembly along with the current collector is welded to the lid portion. However,
uneven surfaces and air gaps resulting from improper crushing may complicate
the welding process. This may result in weak or inconsistent welds, potentially
compromising the electrical connection and seal integrity of the energy storage
25 device.
[0014] Accordingly, it is desirable to provide an improved design for energy
storage devices that addresses the limitations of conventional crushing methods
to enhance electrical conductivity, improper welding integrity, and increase
overall reliability.
4
[0015] Examples of a tabless energy storage device are described. The
tabless energy storage device includes a conductive layer with a patterned
surface for ensuring controlled deformation of the conductive layer. The
conductive layer is integrated to an electrode of an energy storage device. In an
5 example, the conductive layer includes a sheet of conductive material which is to
be integrated with the electrode of the energy storage device. The sheet includes
a first portion and a second portion, wherein the second portion is adjacent to the
first portion. The first portion of the sheet, when integrated with the electrode,
extends along and is coplanar with a surface of the electrode, either to the
10 cathode electrode or the anode electrode, comprised in the electrode assembly.
On the other hand, the second portion is configured to provide an electrical
connection between the respective electrode and a lid portion (or terminal) of the
energy storage device.
[0016] The conductive layer further includes a plurality of edges defining a
15 pattern on the first portion of the sheet. In an example, the plurality of edges
demarcates corresponding portions and are arranged in multiple directions on the
first portion forming a network of interconnected lines along the surface of the first
portion. The plurality of edges are formed on the first portion using a knurling
technique. In an example, knurling is a manufacturing process which is used to
20 create a patterned texture on a surface, typically metal. In context of present
subject matter, the knurling technique refers to the method of creating the plurality
of edges defining the pattern on the conductive layer. Upon crushing, the
conductive layer is to collapse along the plurality of edges, resulting in different
portions of the conductive layer folding to create a compact multi-layer structure
25 comprising the corresponding portions.
[0017] It may be noted that the conductive layer is an integral part of the
electrodes in the energy storage device. The conductive layer is integrated to the
electrodes during the electrode assembly process. For example, in a cylindrical
battery configuration, integrating conductive layer involves integrating the
30 conductive layer to either the cathode or anode electrode. In an example, the
5
conductive layer’s is integrated to electrode material from the side of first portion,
often through welding or another bonding technique, ensuring a strong electrical
connection. During the process of assembling the electrode assembly the
cathode, separator, and anode layers are wound together with the conductive
5 layer integrated to the respective electrode. The conductive layer is so positioned
that it extends beyond the main body of the electrode assembly. This extended
conductive layer is later crushed with the help of pattern formed on its surface
using a crushing process and then serve as a connection point to the external
circuitry.
10 [0018] Once the electrode assembly with the integrated conductive layer is
assembled, it is inserted into the energy storage device casing. This casing is
typically a cylindrical or prismatic container designed to house the electrode
assembly and electrolyte. The electrode assembly is carefully positioned within
the casing of the energy storage device so that the crushed conductive layer
15 aligns with the intended connection point on the lid portion.
[0019] The above-described design or pattern formed on the conductive layer
offers various advantages over conventional conductive layer without any design.
For example, the pattern formed on the conductive layer enables controlled and
uniform folding of layer during crushing process which results in a more
20 consistent and denser structure formed on top or bottom of the electrode
assembly. This improved structure enhances electrical conductivity by minimizing
air gaps and increasing contact area within the lid portion. Furthermore, the
patterned design on the conductive layer allows for better distribution of crushing
forces, reducing the risk of layer damage or failure during high-current extraction
25 scenarios. The more uniform crushed structure also improves the laser welding
process, leading to stronger and more reliable connections between the thus
formed current collector and the cell lid. This enhanced connection integrity
contributes to better overall cell sealing, reducing the potential for electrolyte
leakage and improving long-term cell reliability.
6
[0020] Additionally, the patterned design on the conductive layer enables
more precise control over the final cell height, ensuring consistent pressure
distribution within the cell and better fitment in battery packs. The improved
thermal properties of the crushed patterned conductive layer may also contribute
5 to enhanced heat dissipation, potentially improving the cell's thermal
management capabilities.
[0021] The above aspects are further described in conjunction with the
figures, and in associated description below. It should be noted that the
description and figures merely illustrate principles of the present subject matter.
10 Therefore, various assembly that encompass the principles of the present subject
matter, although not explicitly described or shown herein, may be devised from
the description, and are included within its scope.
[0022] FIG. 1 illustrates a front view of a conductive layer 100 of an energy
storage device, in accordance with an implementation of the present subject
15 matter. In an example, the conductive layer 100 is configured to provide an
electrical connection between an electrode (either a cathode or an anode) of an
energy storage device (not shown) and external circuit via connecting with a lid
portion (not shown). The conductive layer 100 include or is made up of a sheet
102 of conductive material which is to be integrated with an electrode of the
20 energy storage device. For example, the sheet 102 is made of up a metal, e.g.,
for the conductive layer 100 which is integrated with the cathode electrode, the
sheet 102 may be made up of aluminium. In case of integration of the conductive
layer 100 to the anode electrode, the sheet 102 may be made up of copper. It
may be noted that the above disclosed examples of metals are exemplary and
25 any other metal or even alloys may be used for making the sheet 102.
[0023] Continuing further, the sheet 102 includes a first portion 104 and a
second portion 106, wherein the second portion 106 is laterally adjacent to the
first portion 104. In an example, the first portion 104, when integrated with the
electrode, extends along and is coplanar with a surface of the electrode (either
30 cathode electrode or anode electrode) of the energy storage device. Such
7
integration of the conductive layer 100 with the electrode may be achieved
through various techniques, depending on the specific design and requirements
of the energy storage device. Examples of some of the techniques include, but
are not limited to, direct deposition, co-extrusion, sintering, use of conductive
5 adhesives, in-situ formation, laser welding, roll-to-roll processing, and mechanical
pressing. On the other hand, the second portion 106 which is extending adjacent
to the first portion is to provide an electrical connection between the electrode to
which the first portion 104 is integrated and a lid portion of the energy storage
device. In an example, the second portion 106 may be connected to the lid portion
10 via welding.
[0024] Further, as depicted in FIG. 1, the conductive layer 100 further
includes a plurality of edges 108 defining a pattern 110 on the first portion 104 of
the sheet 102. Examples of pattern 110 includes, but are not limited to, a diamond
pattern, a wavy pattern, a zigzag pattern, a geometric pattern, or combination
15 thereof. The plurality of edges 108 (referred to as edges 108) demarcate portions
on the first portion 104 and are arranged in multiple directions forming a network
of interconnected lines along the surface of the first portion 104. The edges 108
may be arranged in various configurations, such as parallel lines, intersecting
lines, or more complex geometric shapes. The pattern 110 may be formed by
20 creating raised or indented lines along the sheet’s surface, effectively producing
a network of edges.
[0025] In an example, these edges 108 serve as predetermined folding
guides during a crushing process. For example, when pressure is applied to the
conductive layer 100 via any crushing means, the conductive layer 100 tends to
25 collapse along these edges 108 of the pattern 110. Such controlled collapsing
behaviour allows for a more predictable and uniform deformation of the
conductive layer 100, resulting in different portions of the conductive layer folding
to create a compact multi-layer structure comprising the demarcated portions.
This compact multi-layer structure may serve as a current collector plate for the
30 electrode assembly. The pattern 110 may be formed using various manufacturing
8
techniques. For example, it may be stamped, embossed, or etched onto the
sheet’s surface. Amongst various tools, a knurling tool is comparatively effective
for the formation of pattern 110 on the first portion 104 of the sheet 102.
[0026] It may be noted that, the specific arrangement and density of these
5 edges may be tailored to achieve desired folding characteristics. For example, a
denser pattern of edges might result in more intricate folds, while a sparser
pattern may lead to larger, more pronounced folds. Further, the orientation of the
edges 108 relative to the conductive layer’s length and width may also influence
the final shape of the crushed conductive layer.
10 [0027] Further, it may be noted that the first portion 104 extend along a
predetermined length of the sheet 102, implying that the first portion 104
corresponds to a specific area of sheet 102 which is intentionally chosen area
rather than the entire sheet. As is clearly seen in FIG. 1, the conductive layer 100
further includes an unpatterned portion 112 which is present on the second
15 portion 106 adjacent to the first portion 104. This indicates that the second portion
106 of the conductive layer 100 remain in its original, unmodified state without
the pattern 110. The unpatterned portion 112 creates a distinct contrast to the
patterned section, resulting in conductive layer with two different surface
characteristics.
20 [0028] It may be noted that, although in FIG. 1, the unpatterned portion 112
is depicted at only end of the sheet 102, however, it may be formed at both ends
of the ends for fulfilling different purposes. For example, the unpatterned portion
112 on the distant end of first portion 104 may provide a smooth surface for
secure attachment to the electrode, while the unpatterned portion 112 on the
25 second portion 106 may facilitate better welding or connection to the terminal or
lid portion of the energy storage device. The combination of patterned and
unpatterned sections on the conductive layer 100 may allow for optimized
performance in different areas of the conductive layer's functionality.
[0029] It may be noted that the patterned section of the conducive layer 100,
30 formed on the first portion 104, may influence how the conductive layer behaves
9
during the crushing process. For example, the pattern 110 guides the way the
conductive layer folds or collapse when pressure is applied, leading to more
predictable and controlled crushing outcomes. In contrast, the unpatterned
portion at one or both ends of the conductive layer 100 maintains its original
5 surface properties.
[0030] While the conductive layer 100 described in the present subject matter
is primarily contextualized within tabless battery configurations, it is important to
note that this design is not limited to such applications. The conductive layer, with
its unique patterned structure and controlled deformation capabilities, may also
10 be effectively implemented in strip type tab batteries, offering similar advantages
and performance enhancements.
[0031] In strip type tab batteries, where traditional tabs or strips extend from
the electrode to provide electrical connections, the conductive layer of the present
invention could be adapted to replace or augment these conventional tabs. The
15 patterned portion of the conductive layer could be integrated with the protruding
tab or strip. This configuration would retain the benefits, such as improved crush
resistance, controlled deformation, and optimized electrical conductivity, while
fitting within the form factor of strip type tab batteries.
[0032] The pattern formed on the conductive layer, whether it be a diamond,
20 wavy, zigzag, or other geometric pattern, would still facilitate the controlled folding
and deformation of the tab when subjected to mechanical stresses during battery
assembly or operation. This feature could enhance the durability and
performance of strip type tab batteries, potentially reducing the risk of tab
detachment or breakage, which are common failure modes in such battery
25 designs.
[0033] By extending the application of this conductive layer design to strip
type tab batteries, manufacturers may potentially benefit from a more versatile,
robust, and efficient electrode structure across various battery form factors and
designs. This broader applicability underscores the versatility and potential
10
impact of the present invention in advancing energy storage technology beyond
just tabless battery configurations.
[0034] FIG. 2 illustrates exemplary dimensions of various portions of a
conductive layer, such as conductive layer 100, in accordance with an example
5 of the present subject matter. The figure provides a detailed visual representation
of the conductive layer's structure, highlighting the specific measurements of
different portions of the conductive layer 100. Within FIG. 2, conductive layer 202
depicts the dimensions of various portions of a conducive layer, which is
integrated with either a cathode or an anode, offering a clear view of its structural
10 layout and size specifications.
[0035] The conductive layer 202 feature a pattern, such as pattern 110,
consisting of a series of intersecting diagonal lines that create a diamond-shaped
geometric pattern. This pattern extends across a first portion, such as first portion
104 of the conductive layer 202. The patterned area or the first portion 104 of the
15 conducive layer 202 may have a length ranging from about 80% to about 99% of
the total layer’s length. The pattern 110 is characterized by the plurality of edges
forming the diamond shapes, with each edge having a depth that may range from
about 0.01 mm to about 0.1 mm. This shallow depth ensures that the pattern
influences the layer's behavior without significantly compromising its overall
20 thickness or structural integrity.
[0036] Adjacent to first portion 104, there is an unpatterned portion, such as
unpatterned portion 112 which is present on the second portion 106 of the
conductive layer 202. In one exemplary example, this unpatterned portion 112
may also be present on the first portion 104 as well at the end which is integrated
25 with the electrode. The length of this unpatterned portion may range from about
0.5 mm to about 1 mm, providing a small but precisely defined area of unmodified
surface. As depicted in FIG. 2, measurement ‘a’ and ‘c’ may range from about 0.5
mm to about 1 mm depending on the requirement. For example, measurement
‘a’ when act as the second portion 106 and is configured to be connected to the
30 lid portion, it may have a value of 1 mm. On the other hand, measurement ‘c’
11
representing unpatterned portion formed on the first portion 104 and is configured
to be connected to the electrodes, it may have a value of about 0.5 mm. Further,
the length of the pattern 110 or the length of the first portion 104 ranges from
about 3 mm to 3.5 mm. For example, in case of cathode electrode, the length of
5 first portion 104 is 3 mm (depicted by measurement ‘b’). On the other hand, in
case of anode electrode, the length of the first portion 104 is 3.5 mm (also
depicted by measurement ‘b’).
[0037] The thickness of the conducive layer, which is not explicitly shown in
the two-dimensional representation of FIG. 2, may range from about 0.1 mm to
10 about 0.5 mm for the cathode electrode, and from about 0.05 mm to about 0.3
mm for the anode electrode, reflecting the different material properties of the
aluminum typically used for cathode electrodes and the copper typically used for
anode electrode.
[0038] These precise dimensions and pattern configurations demonstrate a
15 meticulous approach to layer design, where even small variations in surface
structure and size are carefully controlled to optimize the conducive layer's
performance in terms of mechanical properties, electrical conductivity, and
behavior during the battery assembly process. Further, it may be noted that the
above disclosed dimensions of various portions of conductive layer 202 are
20 exemplary, and may be adjusted or modified based on specific design
requirements, battery size, electrode type, or other factors relevant to the energy
storage device's performance and manufacturing process. The exact dimensions
may vary depending on the intended application, the materials used, and the
desired electrical and mechanical properties of the conductive layer. These
25 dimensions can be optimized through experimentation and testing to achieve the
best balance between conductivity, structural integrity, and overall battery
performance.
[0039] FIG. 3 illustrates a front view of another example of a conductive layer
300 for an energy storage device, depicting an alternative pattern for the
30 conductive layer’s surface. This figure depicts a different approach to conductive
12
layer design, utilizing a hexagonal pattern instead of the diamond pattern shown
in FIG. 2.
[0040] The conducive layer 300 features a pattern 302 formed on at least one
of its surfaces, which consists of a geometric arrangement of a plurality of edges
5 304 (referred to as edges 304). The pattern 302 covers a predetermined length
of the layer's surface. The pattern 302 is composed of interconnected hexagonal
shapes, creating a honeycomb-like structure across the conductive layer's
surface. These hexagons are formed by a series of intersecting lines, with the
edges 304 of the hexagons clearly defined. This creates distinct boundaries
10 between each shape, potentially influencing how the conductive layer deforms
under pressure.
[0041] On the left side of the figure, an enlarged view of a single hexagon
from the pattern 302 is provided. The enlarged view depicts a clearer view of the
hexagonal shape and its edges 304, demonstrating the precise geometry of the
15 pattern. The edges 304 of the hexagons may have a depth ranging from about
0.01 mm to about 0.1 mm, similar to the depth range specified for the diamond
pattern in FIG. 2.
[0042] The hexagonal pattern 302 extends across the majority of the layer's
visible surface, potentially covering about 80% to 99% of the total layer length.
20 As with the design in FIG. 2, there may be unpatterned portions adjacent to one
or both ends of the conducive layer 300, though these are not explicitly shown in
this figure. These unpatterned portions, if present, may have lengths ranging from
about 0.5 mm to about 1 mm.
[0043] This hexagonal pattern design represents an alternative approach to
25 conductive layer surface modification. The honeycomb structure may offer
different mechanical properties compared to the diamond pattern, potentially
providing unique benefits in terms of how the layer deforms during the crushing
process or how it maintains electrical contact within the energy storage device.
The choice between this hexagonal pattern and the diamond pattern shown in
13
FIG. 2 would depend on specific design requirements and performance
objectives for the energy storage device.
[0044] It may be noted that, the diamond shaped pattern and hexagonal
pattern are exemplary, and any other type of pattern may be formed on the
5 conductive layer’s surface without deviating from the scope of the present subject
matter.
[0045] FIG. 4 illustrates an orthogonal front view of an electrode 402 for an
energy storage device (not shown), showcasing the integration of the conductive
layer with the respective electrodes, in accordance with one example of the
10 present subject matter. Although in FIG. 4, the shape of electrode is depicted for
a cylindrical configuration, commonly referred to as a jelly roll structure, however,
any type of electrode depending on the type of the energy storage device may be
used without deviating from the scope of the present subject matter.
[0046] In an example, the electrode 402 includes a coated portion 404 and
15 an uncoated portion 406. The coated portion 404 represent the main body of the
electrode, where the active material is applied to facilitate the electrochemical
reactions of the energy storage device. For example, in case of cathode
electrode, the active material will be copper and in case of anode electrode, the
active material will be aluminium. This coated portion 404 occupies the majority
20 of the electrode’s area and is responsible for the primary energy storage function.
It may be noted although, the electrode 402 in FIG. 2 is depicted as a single
element, however, it may be formed by integrated two separate portions, e.g., the
coated portion 404 is integrated with the uncoated portion 406, without deviating
from the scope of the present subject matter.
25 [0047] The uncoated portion 406 serves as the conductive layer which
includes a sheet 408 integrated with the coated portion 404 of the electrode 402.
This sheet 408 is made up of a conductive material. This sheet 408 is further
divided into two distinct sections, such as a first portion 410, extending along and
coplanar with a surface of the coated portion 404, and a second portion 412
30 extending adjacent to the first portion 410 and is to provide an electrical
14
connected between the coated portion 404 and a terminal of the energy storage
device. The first portion 410 provides a seamless transition from the active
material area of the electrode 402, ensuring good electrical contact between the
two regions.
5 [0048] The first portion 410 further features a plurality of edges 414 defining
a pattern 416 on the first portion 410. The plurality of edges 414 demarcate
corresponding portions and are arranged in multiple directions forming a network
of interconnected lines along the surface of the first portion 410. The plurality of
edges 414 are clearly visible in the enlarged view provided in the lower part of
10 the FIG. 4. The pattern 416 is designed to facilitate controlled deformation of the
sheet 408 when subjected to crushing forces during the assembly or operation of
the energy storage device. This design allows the sheet 408 to collapse along
the plurality of edges 414 in a predictable manner, resulting in different portions
of the sheet folding or collapsing to create a compact multi-layer structure
15 comprising the corresponding portions. potentially enhancing its performance
and durability within the energy storage device. Examples of pattern 416 include,
but are not limited to, a diamond pattern, a wavy pattern, a zigzag pattern, a
geometric pattern, or a combination thereof.
[0049] The second portion 412 is an unpatterned portion as compared to the
20 first portion 410 which has pattern 416 formed thereon. This unpatterned portion
area may serve specific purposes such as providing a smooth surface for
connections or attachments to the terminal of the energy storage device.
[0050] FIG. 5 illustrates an exploded view of an energy storage device 500,
according to an example of the present subject matter. FIG. 5 provides a
25 comprehensive look at its key components and their spatial relationships. This
figure demonstrates how the patterned conductive layer is integrated into the
overall energy storage device and highlights its connection to other elements.
[0051] The energy storage device 500 includes a cylindrical casing 502
(referred to as casing 502), which forms the main body of the energy storage
30 device 500. The casing 502 is designed to house the internal components and
15
may be constructed from a durable, conductive material such as stainless steel
or aluminum. The casing 502 may have a specified height depending on the
usage of the energy storage device and power required from the energy storage
device.
5 [0052] The casing 502 is configured to receive an electrode assembly 504. It
may be noted that the casing 502 and the electrode assembly 504 are depicted
as cylindrical in shape, however, any other type or shape of components may be
used without deviating from the scope of the present subject matter. The
electrode assembly 504 appears to be wound in a spiral configuration, typical of
10 many battery designs, and may have dimensions slightly smaller than the internal
dimensions of the casing 502 to ensure a proper fit.
[0053] The electrode assembly 504 further includes a cathode electrode, an
anode electrode, and a separator between the cathode electrode and the anode
electrode. The respective electrodes of the electrode assembly 504 further
15 includes a conductive layer 506, similar to the conductive layer 100, integrated
with electrodes comprised within the electrode assembly 504. The conductive
layer 506 is depicted with a textured or patterned surface to facilitate controlled
deformation. As described above as well, the conductive layer 506 including a
sheet of conductive material integrated with the cathode electrode and the anode
20 electrode. The sheet comprises a first portion extending along and coplanar with
a surface of one of the electrodes, and a second portion extending adjacent to
the first portion and is to provide an electrical connection between the electrode
and a terminal of the energy storage device 500. The conductive layer 506
includes a plurality of edges defining a pattern on the first portion. The plurality of
25 edges demarcates corresponding portions and are arranged in multiple directions
forming a network of interconnected lines along the surface of the first portion.
[0054] Further, the energy storage device 500 includes a circular lid portion
508 (which may be referred to as lid portion 508 or terminal) to seal the top of the
casing 502, enclosing the electrode assembly 504 with the conductive layer 506
30 within the energy storage device 500. The lid portion 508 may be made of a
16
conductive material and serves as one of the terminals. It may be noted that in
FIG. 5 conductive layer 506 is depicted as integrated to top of the electrode
assembly 504, however, the same be integrated at the bottom or at both ends for
both the electrodes without deviating from the scope of the present subject
5 matter.
[0055] Upon crushing, the conductive layer 506 is designed to collapse along
the edges, resulting in different portions of the conductive layer folding to create
a compact multi-layer structure comprising the corresponding portions. Further,
upon crushing, the conductive layer 506 forms a planar surface which may be
10 referred to as current collector and is welded to the lid portion 508 to form a
secure electrical connection between the electrode assembly 504 and the
external terminal of the energy storage device 500. The patterned design of the
conductive layer 506 plays a crucial role in this welding process as the pattern
allows for controlled deformation of the conductive layer during crushing,
15 potentially improving the quality and reliability of the weld. The welding process
may involve techniques such as ultrasonic welding, resistance welding, or laser
welding. The specific pattern on the conductive layer 506 may influence how it
deforms and forms a uniform surface for welding, potentially leading to a stronger
and more consistent weld joint. This could enhance the electrical conductivity
20 between the electrode assembly 504 and the lid portion 508, as well as improve
the mechanical strength of the connection.
[0056] Although aspects and other examples have been described in a
language specific to structural features and/or methods, the present subject
matter is not necessarily limited to such specific features or elements as
25 described. Rather, the specific features are disclosed as examples and should
not be construed to limit the scope of the present subject matter.
17
I/We Claim:
1. A conductive layer (100) for an energy storage device comprising:
5 a sheet (102) of conductive material to be integrated with an electrode of
the energy storage device, wherein the sheet (102) comprising:
a first portion (104), when integrated with the electrode, extends
along and is coplanar with a surface of the electrode;
a second portion (106) extending adjacent to the first portion and is
10 to provide an electrical connection between the electrode and a terminal of
the energy storage device; and
a plurality of edges (108) defining a pattern (110) on the first portion
(104), wherein the plurality of edges (108) demarcate corresponding
portions and are arranged in multiple directions forming a network of
15 interconnected lines along the surface of the first portion (104), and wherein
upon crushing, the conductive layer (100) is to collapse along the plurality
of edges (108), resulting in different portions of the conductive layer folding
to create a compact multi-layer structure comprising the corresponding
portions.
20
2. The conductive layer (100) as claimed in claim 1, wherein the first portion
(104) with pattern (110) extends along a predetermined length of the sheet (102)
and an unpatterned portion (112) present on the second portion (106).
25 3. The conductive layer (100) as claimed in claim 2, wherein the unpatterned
portion (112) has a length in a range of about 0.5 mm to about 1 mm.
4. The conductive layer (100) as claimed in claim 1, wherein the pattern (110)
defined on the first portion (104) is created by a knurling technique during
30 assembling an electrode assembly.
18
5. The conductive layer (100) as claimed in claim 1, wherein the pattern (110)
is one of a diamond pattern, a wavy pattern, a zigzag pattern, a geometric pattern,
or combination thereof.
5
6. The conductive layer (100) as claimed in claim 1, wherein the plurality of
edges (108) has a depth in a range of about 0.01 mm to about 0.1 mm on the first
portion (104).
10 7. An electrode (402) for an energy storage device comprising:
a coated portion (404) covered with an active material; and
an uncoated portion (406), wherein the uncoated portion (406) of
the electrode (402) comprises:
a sheet (408) integrated with the coated portion (404) of the
15 electrode (402), wherein the sheet (408) comprising:
a first portion (410) extending along and coplanar with
a surface of the coated portion (404);
a second portion (412) extending adjacent to the first
portion (410) and is to provide an electrical connection
20 between the coated portion (404) and a terminal of the
energy storage device; and
a plurality of edges (414) defining a pattern (416) on
the first portion (410), wherein the plurality of edges (414)
demarcate corresponding portions and are arranged in
25 multiple directions forming a network of interconnected
lines along the surface of the first portion (410), and wherein
upon crushing, the uncoated portion (406) is to collapse
along the plurality of edges (414), resulting in different
portions of the uncoated portion (406) folding to create a
19
compact multi-layer structure comprising the corresponding
portions.
8. The electrode (402) as claimed in claim 7, wherein the first portion (410)
5 with pattern (416) extends along a predetermined length of the sheet (408) and
an unpatterned portion present on the second portion (412).
9. The electrode (402) as claimed in claim 8, wherein the unpatterned portion
has a length in a range of about 0.5 mm to about 1 mm.
10
10. The electrode (402) as claimed in claim 7, wherein the pattern (416) defined
on the first portion (410) is created by a knurling technique during manufacturing
of the electrode (402).
15 11. The electrode (402) as claimed in claim 7, wherein the pattern (416) is one
of a diamond pattern, a wavy pattern, a zigzag pattern, a geometric pattern, or
combination thereof.
12. An energy storage device (500) comprising:
20 a casing (502):
an electrode assembly (504) comprising a cathode electrode, an
anode electrode, and a separator between the cathode electrode and the
anode electrode; and
a conductive layer (506) comprising:
25 a sheet of conductive material integrated with the cathode
electrode and the anode electrode, wherein the sheet comprises:
a first portion extending along and coplanar with a
surface of one of the electrodes;
a second portion extending adjacent to the first portion
30 and is to provide an electrical connection between the
20
electrode and a terminal (508) of the energy storage device
(500); and
a plurality of edges defining a pattern on the first
portion, wherein the plurality of edges demarcate
5 corresponding portions and are arranged in multiple directions
forming a network of interconnected lines along the surface of
the first portion, and wherein upon crushing, the conductive
layer is to collapse along the plurality of edges, resulting in
different portions of the conductive layer folding to create a
10 compact multi-layer structure comprising the corresponding
portions.
13. The energy storage device (500) as claimed in claim 12, wherein the first
portion with pattern extends along a predetermined length of the sheet and an
15 unpatterned portion present on the second portion.
14. The energy storage device (500) as claimed in claim 12, wherein the pattern
is one of a diamond pattern, a wavy pattern, a zigzag pattern, a geometric pattern,
or combination thereof.
20
15. The energy storage device (500) as claimed in claim 12, wherein the pattern
defined on the first portion is created by a knurling technique during assembling
the electrode assembly (504).