The present application claims priority to Korean Patent Application No. 10-2021-0114128 filed on Aug. 27, 2021 in the Republic of Korea, the disclosure of which is incorporated herein by reference.
The present disclosure relates to a battery module, and more specifically, to a battery module efficiently improving the assembly position and connection structure of a bus bar plate and an inter connection board (ICB) assembly, which are components for electrical connection or voltage sensing of battery cells, and a battery pack including the same.
Secondary batteries have high applicability according to product groups and electrical characteristics such as high energy density, and thus are commonly applied not only to portable devices but also to electric vehicles (EVs), hybrid electric vehicles (HEVs), or electric scooters driven by electric power sources. Such a secondary battery is attracting attention as a new energy source to improve eco-friendliness and energy efficiency in that it has not only a primary advantage of dramatically reducing the use of fossil fuels, but also no by-products generated from the use of energy.
Secondary batteries widely used at present include lithium-ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and the like. An operating voltage of the unit secondary battery cell, namely a unit battery cell, is about 2.5 V to 4.5 V. Therefore, currently, a single secondary battery (cell) is not capable of obtaining sufficient output to drive, for example, an electric scooter. In order to apply a secondary battery as an energy source for an electric scooter, for example, a battery module in which a plurality of lithium-ion battery cells are connected in series and/or in parallel should be configured, and in general, a battery pack including a battery management system (BMS), a battery disconnection unit (BDU), electrical connection parts, and the like for connecting the battery modules in series and maintaining the same functionally is configured.
Meanwhile, the battery module 1 or the battery pack according to the prior art uses the cable connector 2 as an example of a configuration for sensing the voltage information of the battery cells and transmitting it to the BMS, thereby connecting the terminals 3 of each cable (connected to the positive electrode or negative electrode of the battery cell) to the metal plates 4 and connecting a connector 5 to the BMS circuit board (not shown), as shown in
Accordingly, in order to simplify and streamline the design of a battery module or a battery pack, recently, voltage sensing components provided in the form of a printed circuit board instead of a bus bar plate and the cable connector are widely used for electrical connection of battery cells or electrical connection of voltage sensing components, and wire bonding technology is widely used as an electrical connection method.
However, the wire bonding technology is a method of ultrasonically welding both ends of a very thin metal wire to a connection object, so there is a risk of wire breakage in case of external impact. In particular, if the bus bar plate or the voltage sensing component is moved even a little due to external impact or vibration, the wire between the bus bar plate and the voltage sensing component may be easily disconnected, and in this case, it is impossible to sense the voltage of the battery cells, which may cause a problem in the function of the battery module.
The present disclosure is designed to solve the problems of the related art, and therefore the present disclosure is directed to providing a battery module that prevents wire breakage even from external impact or vibration by improving the assembly position and structure between the bus bar plate and the ICB assembly.
That is, the present disclosure is directed to providing a battery module capable of not only changing the configuration, assembly structure, and connection method of components for electrical connection and voltage sensing of battery cells more efficiently than in the prior art, but also sufficiently securing electrical connection rigidity, and a battery pack including the same.
However, technical problems to be solved by the present disclosure are not limited to the above-described problems, and other problems not mentioned herein may be clearly understood by those skilled in the art from the following description of the present disclosure.
A battery module according to an aspect of the present disclosure for achieving the above object may include battery cells having a battery can and a top cap coupled to the battery can; a cell frame provided to accommodate and fix the battery cells therein; bus bar plates spaced apart from each other and disposed on an outer side of the cell frame and electrically connected to the battery cells; and an inter connection board (ICB) assembly having sensing plates electrically connected to the bus bar plates, respectively, and mounted on the other outer side of the cell frame, wherein each of the bus bar plates and each of the sensing plates may have portions that overlap vertically and are fixed so as not to move relative to each other, and may be electrically connected by a conductive wire.
One end of the sensing plate may be positioned under one end of the bus bar plate, and one end of the sensing plate may have a ‘U’-shaped rabbit ear part.
One end of the sensing plate may be seated on an adhesive applied to the surface of the cell frame, and one end of the bus bar plate may be mutually bonded to one end of the sensing plate by the adhesive coming up through the rabbit ear part.
The cell frame may include a side portion forming a wall surrounding the outside of the entire battery cells and an upper surface portion covering the top of the battery cells, and one end of the bus bar plates and one end of the sensing plates may be disposed to overlap each other at one edge of the upper surface portion.
The ICB assembly may further include a printed circuit board to which the sensing plates are coupled; and a cable connector mounted on the printed circuit board, wherein the printed circuit board may be disposed such that a plate surface thereof faces a side portion of the cell frame.
The sensing plate may be provided in a ‘¬’ shape and, may include a substrate mounting portion attached to the printed circuit board and a frame mounting portion bent and extended with respect to the substrate mounting portion, wherein the frame mounting portion may be disposed to face an edge surface of the upper surface portion of the cell frame.
The upper surface portion may include first plate seating grooves extending along the lengthwise direction of the cell frame to be provided at predetermined intervals along the widthwise direction of the cell frame, and provided such that the bus bar plate may be seated; and second plate seating grooves provided at one edge of the cell frame and straightly connected to each of the first plate seating grooves, the surface of which is formed lower than the first plate seating grooves, and provided such that the sensing plate may be seated.
The first plate seating groove may have a bus bar hanging pin formed to protrude from the surface thereof, and the bus bar plate may have a pin hole into which the bus bar hanging pin may be inserted.
The second plate seating groove may be provided to be shape-fitted with the rabbit ear part of the sensing plate.
The cell frame may include a cell bottom frame having cell insertion holes capable of respectively inserting lower regions of the battery cells; and a cell top frame that covers upper regions of the battery cells and is provided to be coupled to the cell bottom frame.
The battery cells may be cylindrical battery cells, and may be inserted into the cell bottom frame to be disposed so that the top cap faces the cell top frame.
The cell top frame may include an upper surface portion covering the upper side of the battery cells, wherein the upper surface portion may have first holes perforated so that each top cap of the battery cells may be exposed to the outside, and second holes perforated so that the upper ends of each battery can of the battery cells may be partially exposed to the outside.
Each of the bus bar plates may be connected to the top cap exposed through the first holes or the upper end of the battery can exposed through the second holes by wires.
One end of the sensing plate may be positioned under one end of the bus bar plate, and an ICB hanging pin formed to protrude from the surface of the cell frame on which one end of the sensing plate is seated may be provided, wherein one end of the sensing plate may have a through hole into which the ICB hanging pin may be inserted.
According to another aspect of the present disclosure, there may be provided a battery pack including the battery module described above.
According to the present disclosure, there may be provided a battery module that prevents wire breakage even from external impact or vibration by improving the assembly position and structure between the bus bar plate and the ICB assembly.
In addition, according to the present disclosure, there may be provided a battery module that simplifies the wiring structure, and the like as a whole and has excellent reliability in electrical connection by efficient configuration, assembly structure, and connection method of components for electrical connection of battery cells and voltage sensing, and a battery pack including the same.
However, effects to be obtained by the present disclosure are not limited to the above-described effects, and other effects not mentioned herein may be clearly understood by those skilled in the art from the following description of the present disclosure.
Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Prior to the description, it should be understood that the terms used in the specification and the appended claims should not be construed as limited to general and dictionary meanings, but interpreted based on the meanings and concepts corresponding to technical aspects of the present disclosure on the basis of the principle that the inventor is allowed to define terms appropriately for the best explanation.
Therefore, the description proposed herein is just a preferable example for the purpose of illustrations only, not intended to limit the scope of the present disclosure, so it should be understood that other equivalents and modifications could be made thereto without departing from the scope of the present disclosure.
Referring to these drawings, the battery module 10 according to an embodiment of the present disclosure includes battery cells 100, a cell frame 200, bus bar plates 300, and an ICB assembly 400 having sensing plates 410 electrically connected to the bus bar plates 300, respectively and mounted on the other side of the outer side of the cell frame 200.
The battery cells 100 may be cylindrical battery cells 100 in which an electrode assembly is embedded in a metal can. The cylindrical battery cell 100 may be configured to include a battery can 120 mainly made of a lightweight conductive metal material such as aluminum in a cylindrical shape, a jelly-roll type electrode assembly accommodated in the battery can 120, and a top cap 110 coupled to the upper portion of the battery can 120. The top cap 110 is connected to the positive electrode tab of the electrode assembly to function as a positive electrode terminal, and the battery can 120 is connected to the negative electrode tab of the electrode assembly to function as a negative electrode terminal.
The cylindrical battery cell 100 may be inserted and disposed in the cell frame 200, and the cylindrical battery cells 100 are bonded to the bus bar plates 300 by wire 500 in a predetermined pattern to be connected in series and/or in parallel to each other. A more detailed description of this will be given later.
On the other hand, the scope of the present disclosure need not be necessarily interpreted to be limited to the battery module 10 to which the cylindrical battery cell 100 is applied. For example, the battery module 10 according to the present disclosure may be configured using a can-type battery cell having a rectangular parallelepiped shape or other shape, other than a cylindrical shape in the battery can 120.
The cell frame 200 is a structure for accommodating and fixing the battery cells 100 therein to protect the battery cells 100 from external impact or vibration, and in the present embodiment, it may be configured to include the cell bottom frame 210 and the cell top frame 220.
The cell bottom frame 210 may be configured to have cell insertion holes inside the outer rim in a rectangular box shape and to insert the battery cells 100 into the cell insertion holes one by one. For example, as shown in
The cell bottom frame 210 may be firmly coupled to the cell top frame 220 by a long bolt (not shown) together with hook fastening. For example, as shown in
The cell top frame 220 may cover an upper region of the battery cells 100 and may be configured to be coupled to the cell bottom frame 210.
For example, as shown in
In addition, the cell top frame 220 includes an upper surface portion 201 covering the top of the entire battery cells 100 and four side portions 202 forming a wall surrounding the outside of the entire battery cells 100 together with the cell bottom frame 210, wherein the upper surface portion 201, as shown in
The first holes 221 have a configuration in which the cell top frame 220 is partially perforated so that the center of each top cap 110 of the battery cells 100 may be exposed to the outside, and the second holes 222 have a configuration in which the cell top frame 220 is partially perforated so that the upper end of each battery can 120 of the battery cells 100 may be partially exposed to the outside.
For example, as shown in
The first holes 221 and the second holes 222 are used as paths for connecting the battery cells 100 located inside the cell frame 200 to the bus bar plates 300 located outside the cell frame 200 by metal wires 500. For example, the bus bar plate 300 may be connected to the top cap 110 exposed through the first holes 221 or the upper end of the battery can 120 exposed through the second holes 222 by a metal wire 500. For example, a wire bonding method in which one end of the metal wire 500 is ultrasonically welded to the top cap 110 or an upper end of the battery can 120 and the other end of the metal wire 500 is ultrasonically welded to the bus bar plate 300 may be employed.
The first plate seating groove 223 is a place where the bus bar plate 300 is to be seated and fixed, and may extend along the lengthwise direction (Y-axis direction) of the cell frame 200 to be provided at predetermined intervals in the widthwise direction (X-axis direction) of the cell frame 200. For example, a total of eight first plate seating grooves 223 according to the present embodiment may be provided between rows of the battery cells 100 from the left side of the first row battery cells 100 to the right side of the seventh row battery cells 100. A bus bar plate 300, which is a straight metal conductor having the same left and right widths, may be disposed in each of the first plate seating grooves 223.
The bus bar plate 300 has the same left and right widths as the first plate seating groove 223, so that its movement in the widthwise direction (X-axis direction) may be blocked, and in the lengthwise direction, its movement may be blocked by the bus bar hanging pin 223a. The bus bar hanging pin 223a may be provided in the form of a pin or a pillar formed to protrude from the surface of the first plate seating groove 223 (in the Z-axis direction). The bus bar plate 300 has a pin hole H corresponding to the diameter of the bus bar hanging pin 223a. When the bus bar plate 300 is seated in the first plate seating groove 223, the bus bar hanging pin 223a may be inserted into the pin hole H. The bus bar hanging pin 223a and the pin hole H may be provided in plurality, and may serve to prevent movement of the bus bar plate 300 and guide the assembly direction.
In the present embodiment, eight first plate seating grooves 223 may be provided, and eight bus bar plates 300 may be disposed in the eight first plate seating grooves 223. Here, the first bus bar plate 301 and the eighth bus bar plate 302 may be enabled as the positive electrode terminal and the negative electrode terminal of the entire battery module 10, and unlike the other bus bar plates 300, they may be configured to partially surround the side portion 202 of the cell top frame 220 in an angled shape.
For example, the first bus bar plate 301 and the top cap 110 of the first row battery cells 100 are bonded by wires 500, and the second bus bar plate 300 and the upper edge of the battery can 120 of the second row battery cells 100 are bonded by wires 500, so that the first row battery cells 100 and the second row battery cells 100 may be respectively connected in parallel, and the battery cells between the first row battery cells 100 and the second row battery cells 100 may be connected in series with each other. When the battery cells 100 and the bus bar plates 300 are connected by wires 500 in this way, the battery cells 100 in the same row from the first to the seventh row battery cells 100 are connected in parallel, and the battery cells 100 in adjacent rows may be connected in series.
The second plate seating groove 224 is a place where the sensing plate 410 is to be seated and fixed, and is straightly connected to each of the first plate seating grooves 223 at one edge of the cell frame 200, but the surface thereof may be formed lower than the first plate seating groove 223.
That is, as shown in
The sensing plates 410 are configured to be electrically connected to each of the bus bar plates 300 in order to read the voltage of each bank (battery cells connected in parallel) of the battery cells 100, and are the main component of an inter connection board (ICB) assembly.
Here, the ICB assembly 400 refers to a component for sensing the voltage or temperature of the battery cells 100 and transmitting it to the BMS (not shown). The ICB assembly 400 according to the present embodiment includes a plurality of sensing plates 410, a printed circuit board 420, a cable connector 430, and temperature sensors 440a, 440b, as shown in
The plurality of sensing plates 410 are made of metal material such as nickel and provied in an approximately ‘’ or ‘
’ shape. Each of the sensing plate 410 includes a substrate mounting portion 411 attached to the printed circuit board 420 and a frame mounting portion 412 bent and extended with respect to the substrate mounting portion 411.
The printed circuit board 420 has a pair of long holes at each predetermined position, and the substrate mounting portion 411 of each sensing plate 410 has a fitting pin 411a to be fitted into the pair of long holes. Each sensing plate 410 may be fixed and electrically connected to the printed circuit board 420 by, for example, soldering after the fitting pin 411a is inserted into the long hole of the printed circuit board 420.
As shown in
When the printed circuit board 420 is disposed to face the side portion 202 of the cell frame 200 as shown in
As described above, in order to place the printed circuit board 420 facing the side portion 202 of the cell frame 200, a pair of substrate holders 227 configured to insert the printed circuit board 420 into the side portion 202 of the cell frame 200 from top to bottom and to partially surround both ends of the printed circuit board 420 to support it, and a plurality of substrate supports 227a configured to support portions between both ends of the printed circuit board 420 between the pair of substrate holders 227 may be provided.
The cable connector 430 is a means for transmitting sensed voltage information or temperature information to the BMS, and may be composed of a plurality of cables C and connectors. One side of the plurality of cables C is mounted on the surface of the printed circuit board 420, and the other side thereof is connected to a connector. The connector may be connected to another connector provided in the BMS. In the ICB assembly 400 having the above configuration, it is very convenient to electrically connect the bus bar plates 300, and the cables from the printed circuit board 420 to the BMS may be combined and wired as one, whereby the line arrangement is very easy.
The temperature sensors 440a, 440b may include two temperature sensors 440a, 440b having different lengths. The relatively long temperature sensor 440a may be used to measure the center temperature of the battery module 10, and the relatively short temperature sensor 440b may be used to measure the outer temperature of the battery module 10.
Referring to the drawings, an electrical connection configuration for sensing voltage of each bank of the battery cells 100 according to an embodiment of the present disclosure will be described in more detail.
As described above, one end of the sensing plate 410, that is, the frame mounting portion 412, is placed in the second plate seating groove 224, and one end 310 of the bus bar plate is placed in the first plate seating groove 223, so that the frame mounting portion 412 of the sensing plate 410 and the one end 310 of the bus bar plate may be partially overlapped up and down. At this time, an adhesive is applied to the surface of the cell frame 200 and the frame mounting portion 412 is seated on the adhesive to fix the sensing plate 410.
In this state, the bus bar plate 300 and the sensing plate 410 are electrically connected by wire 500 bonding. Here, the wire 500 refers to a thin wire 500 having a thickness of about 12.5-350 μm and made of a metal material such as gold, aluminum, copper, or the like. The wire bonding method refers to ultrasonic welding in which an end of the wire 500 is pressed with ultrasonic waves. However, wire bonding is not necessarily limited to ultrasonic welding. That is, laser welding, arc welding, or a bonding method using glue may be applied.
In particular, the frame mounting portion 412 of the sensing plate 410 according to the present embodiment may have a rabbit ear part 413 in an approximately ‘U’ shape, and the second plate seating groove 224 may be provided to be shape-fitted with the rabbit ear part 413 of the frame mounting portion 412.
According to the above configuration, when the frame mounting portion 412 of the sensing plate 410 is seated in the second plate seating groove 224, the adhesive G comes up through the rabbit ear parts 413 and the bus bar plate 300 is placed thereon, and thus, the rabbit ear part 413 and one end 310 of the bus bar plate may be integrally fixed to each other, as shown in
In addition, as described above, the present disclosure is configured to electrically connect the bus bar plates 300 to the ICB assembly 400 by utilizing the edge of the upper surface portion 201 of the cell top frame 220 and one side portion 202 as space-efficiently as possible, so there are advantageous effects in miniaturizing the battery module 10, simplifying the assembly process, and facilitating the electrical wiring work.
Next, a connection configuration between the bus bar plate 300 and the sensing plate 410A of the battery module 10 according to another embodiment of the present disclosure will be further described with reference to
The same reference numbers as in the previous drawings represent the same members, and the repeated description of the same members will be omitted, but differences from the above-described embodiments will be briefly described.
When compared with the battery module 10 of the above-described embodiment, the battery module 10 according to another embodiment of the present disclosure has a difference in the second plate seating groove 224 and the frame mounting portion 412 of the sensing plate 410A.
As shown in
Therefore, according to another embodiment of the present disclosure, the movement of the bus bar plate 300 is blocked by the bus bar hanging pin 223a, and the movement of the sensing plate 410A is blocked by the ICB hanging pin 224a. Also, one end 310 of the bus bar plate and one end of the sensing plate 410A are vertically overlapped, and the adhesive G is permeated into the overlapped portion, so that the relative movement between the bus bar plate 300 and the sensing plate 410 may be reliably blocked even from external impact or vibration by mutually adhesively fixing one end 310 of the bus bar plate and one end of the sensing plate 410, whereby there is no occurrence of disconnection of the metal wire 500 to which the wire 500 is bonded between them.
Meanwhile, the battery pack (not shown) according to the present disclosure may include one or more of the above-described battery modules. The battery pack may further include, in addition to the battery module, a pack case (not shown) for accommodating the battery module, various devices (not shown) for controlling the charge/discharge of the battery module, such as a battery management system (BMS), a current sensor, a fuse, and the like.
While the present disclosure has been hereinabove described with regard to a limited number of embodiments and drawings, the present disclosure is not limited thereto and it is obvious to those skilled in the art that a variety of modifications and changes may be made thereto within the technical aspects of the present disclosure and the equivalent scope of the appended claims.
The terms indicating directions as used herein such as upper, lower, left, and right are used for convenience of description only, and it is obvious to those skilled in the art that the terms may change depending on the position of the stated element or an observer.
Number | Date | Country | Kind |
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10-2021-0114128 | Aug 2021 | KR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/KR2022/012677 | 8/24/2022 | WO |