Battery expansion force detection device

Abstract

The utility model relates to the field of battery detection equipment, and provides a battery expansion force detection device, which comprises a mounting frame, at least two groups of weighing sensor assemblies and a thin film sensor assembly. A battery module is mounted in the mounting frame. A weighing sensor is arranged between the end face of the battery monomer at one end or two ends of the battery module and the mounting rack, a weighing sensor assembly is arranged between at least two adjacent battery monomers in the battery module, and each weighing sensor assembly comprises a plurality of force detection points, so that when the battery monomers are expanded, the force detection points of the weighing sensor assembly can be detected. The expansive force of multiple points on the end face of the single battery can be collected to improve the detection precision. And a group of film sensor assemblies is arranged between each weighing sensor assembly and the end surface of the battery monomer, and is used for detecting the adhesion flatness of the weighing sensor assemblies and the end surface of the battery monomer during initial circulation. The battery expansive force detection device provided by the utility model can accurately collect the expansive force value in the charging and discharging process of the battery module.

Description

Technical Field

[0001] The utility model relates to the technical field of battery detection equipment, in particular to a battery expansion force detection device. Background Art

[0002] With the rapid development of the new energy industry, more and more people prefer electric vehicles due to their advantages such as zero emissions, low pollution, and low energy consumption, and the long-term endurance of electric vehicles has become the focus of most people's attention. The long-term endurance of electric vehicles is the cycle of the battery pack at the PACK end, and battery expansion is a key factor in the battery cycle. In order to understand the impact of battery expansion on battery cycle, various methods for expansion force testing have emerged, among which thin film sensors and weighing sensors have become effective means to monitor expansion force.

[0003] The expansion of the battery affects the cycle life of the entire battery pack. Currently, the most popular expansion force test method is to use a weighing sensor or a thin film sensor to monitor the expansion force, but the two collection methods have their own advantages and disadvantages. Weighing sensors are suitable for the expansion force detection of single cells. They are widely used because their test data is effective and stable. However, weighing sensors can only be used to collect the expansion force of battery cells in the Z direction, or the expansion force at the end of a single module, but cannot collect the expansion force in the middle of the module. Thin film sensors can be used not only for the expansion force detection of single cells, but also for the expansion force detection at the module level and the whole package level. However, due to their instability, thin film sensors are prone to data drift after multiple cycles, and the drift amount is mostly irregular, and the specific expansion force cannot be accurately known. However, the advantage of thin films is that they can detect the stress distribution of the expansion force on the entire battery surface. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model provides a battery expansion force detection device, which aims to solve the defect that the weighing sensor in the prior art can only be used to collect the expansion force of the battery cell in the Z direction or the end expansion force.

[0005] The utility model provides a battery expansion force detection device, comprising:

[0006] A mounting frame, in which a battery module is mounted;

[0007] At least two groups of weighing sensor assemblies, wherein the weighing sensor assemblies are arranged between the end faces of the battery cells at one end or both ends of the battery module and the mounting frame, and the weighing sensor assemblies are arranged between at least two adjacent battery cells in the battery module, and the weighing sensor assemblies have a plurality of force detection points;

[0008] A thin film sensor assembly is arranged between the weighing sensor assembly and the end surface of the battery cell.

[0009] According to the battery expansion force detection device provided by the utility model, the weighing sensor assembly includes:

[0010] A sensor tooling, comprising a first base plate, a first baffle plate and a second baffle plate, wherein the first baffle plate and the second baffle plate are slidably connected, and a sliding direction is perpendicular to an end face of the battery cell;

[0011] At least two weighing sensors, a plurality of the weighing sensors are distributed between the first baffle and the second baffle.

[0012] According to the battery expansion force detection device provided by the utility model, a guide assembly is further provided between the first baffle plate and the second baffle plate, and the guide assembly is used to limit the first baffle plate and the second baffle plate to move only in a direction perpendicular to the end surface of the battery cell.

[0013] According to the battery expansion force detection device provided by the utility model, a heat insulation pad is further arranged between the battery cell and the weighing sensor.

[0014] According to the battery expansion force detection device provided by the utility model, the thin film sensor assembly is arranged between the thermal insulation pad and the battery cell.

[0015] According to the battery expansion force detection device provided by the utility model, the mounting frame includes:

[0016] A frame body, the frame body comprising a top plate, a second bottom plate, and two end plates arranged between the top plate and the second bottom plate;

[0017] Two module fixing plates are arranged between the two end plates, and are used for clamping at two ends of the battery module.

[0018] According to the battery expansion force detection device provided by the utility model, a heat dissipation plate is further provided on a side of the second bottom plate close to the top plate.

[0019] According to the battery expansion force detection device provided by the utility model, the heat sink is a water-cooled plate.

[0020] According to the battery expansion force detection device provided by the utility model, the battery module is connected to the top plate and the second bottom plate by structural adhesive, and a glue blocking device is also provided on the top plate and the second bottom plate. The glue blocking device is located between the battery module and the weighing sensor assembly, and between the battery module and the thin film sensor assembly.

[0021] According to the battery expansion force detection device provided by the utility model, a handle is also provided on the second bottom plate.

[0022] The battery expansion force detection device provided by the utility model comprises a mounting frame, at least two groups of weighing sensor assemblies and a thin film sensor assembly. The mounting frame is used to install the battery module. A group of weighing sensors is arranged between the end face of the battery cell at one end of the battery module and the mounting frame, or a group of weighing sensors is arranged between the end face of the battery cell at both ends of the battery module and the mounting frame, and at the same time, a weighing sensor assembly is arranged between at least two adjacent battery cells in the battery module, and each weighing sensor assembly includes multiple force detection points. In this way, when the battery cell expands, the expansion force of multiple points on the end face of the battery cell can be collected to improve the detection accuracy, so that the weighing sensor assembly can detect the expansion force of the battery module in the X direction. A group of thin film sensor assemblies is arranged between each weighing sensor assembly and the end face of the battery cell, which is used to detect the adhesion and flatness of the weighing sensor assembly and the end face of the battery cell during the initial cycle. The battery expansion force detection device provided by the utility model can more accurately collect the expansion force value of the battery module during the charging and discharging process, and monitor the force condition of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 It is a structural schematic diagram of a battery expansion force detection device provided in an embodiment of the utility model;

[0025] Figure 2 is an exploded view of a battery expansion force detection device provided in an embodiment of the utility model;

[0026] Figure 3 is an exploded view of a weighing sensor assembly provided in an embodiment of the utility model;

[0027] Reference numerals:

[0028] 100: weighing sensor assembly; 111: first bottom plate; 112: first baffle; 113: second baffle; 120: weighing sensor; 131: stud; 132: ball; 133: slide; 141: bushing; 142: set screw; 143: guide column; 200: film sensor assembly; 310: top plate; 320: second bottom plate; 330: end plate; 340: module fixing plate; 350: water cooling plate; 360: adhesive foam; 400: battery module; 500: thermal insulation pad; 600: handle. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be described clearly and completely in conjunction with the drawings in the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] Combine the following Figures 1 to 3 The utility model describes a battery expansion force detection device.

[0031] Before describing the battery expansion force detection device provided by the embodiment of the utility model, the directions are first defined. The direction perpendicular to the end face of the battery cell is the X direction, the direction along the horizontal direction and perpendicular to the X direction is the Y direction, and the direction along the vertical direction is the Z direction. Figure 1 In the figure, the direction from the upper left to the lower right is the X direction, the direction from the lower left to the upper right is the Y direction, and the up-down direction is the Z direction.

[0032] An embodiment of the utility model provides a battery expansion force detection device, which includes a mounting frame, at least two groups of weighing sensor assemblies 100 and a thin film sensor assembly 200 .

[0033] The mounting frame includes a frame body and two module fixing plates 340. The frame body includes a top plate 310, a second bottom plate 320 and two end plates 330 disposed between the top plate 310 and the second bottom plate 320.

[0034] Specifically, the top plate 310 and the second bottom plate 320 are arranged in parallel, and the end plate 330 includes a left end plate and a right end plate, the left end plate and the right end plate are distributed in parallel along the left-right direction, and the left end plate and the right end plate are arranged parallel to the YOZ plane.

[0035] Bolt holes are provided on the top and bottom surfaces of the left and right end plates, at the position where the top plate 310 corresponds to the top surfaces of the left and right end plates, and at the position where the second bottom plate 320 corresponds to the bottom surfaces of the left and right end plates. During installation, the top surfaces of the left and right end plates and the top plate 310, and the bottom surfaces of the left and right end plates and the second bottom plate 320 are fastened together by bolts, so that the left end plate, the right end plate, the top plate 310 and the second bottom plate 320 are connected into an integrated structure.

[0036] The two module fixing plates 340 are both arranged between the two end plates 330. The two module fixing plates 340 are distributed in the left-right direction, and the two module fixing plates 340 are both arranged parallel to the YOZ plane. The area between the two module fixing plates 340 is used to install the battery module 400. The module fixing plates 340 are used to limit the total length of the battery module 400, fix the relative position of the battery module 400, and also limit the expansion of the battery at the end of the battery module 400 to prevent the battery from expanding infinitely and causing cycle failure.

[0037] The module fixing plate 340 may be fixedly connected to the top plate 310 and the second bottom plate 320 by gluing, or may be fixedly connected to the top plate 310 and the second bottom plate 320 by bolting.

[0038] When the connection is made by gluing, the module fixing plate 340 can reasonably select the gluing position according to the total length of the battery module 400 to adapt to the length of the battery module 400 .

[0039] When bolt connection is adopted, bolt holes can be respectively provided on the top and bottom of the module fixing plate 340, and multiple groups of bolt holes corresponding to the bolt holes on the module fixing plate 340 can be provided on the top plate 310 and the second bottom plate 320 along the X direction. During installation, a group of bolt holes can be reasonably selected to align with the bolt holes on the module fixing plate 340 according to the total length of the battery module 400, and bolts can be used for fastening.

[0040] Alternatively, when bolt connection is adopted, bolt holes can be respectively provided on the top and bottom of the module fixing plate 340, and a plurality of adjustment holes extending along the X direction can be provided along the Y direction on the top plate 310 and the second bottom plate 320. During installation, the relative positions of the bolt holes and the adjustment holes can be reasonably selected according to the total length of the battery module 400, and fastened by bolts.

[0041] The top and bottom of the battery module 400 may be bonded to the top plate 310 and the second bottom plate 320 respectively using structural adhesive.

[0042] Furthermore, a receiving groove is provided on one side of the second bottom plate 320 close to the top plate 310 , and a heat sink is provided in the receiving groove. The bottom of the battery module 400 contacts the heat sink for heat dissipation of the battery module 400 .

[0043] The heat dissipation plate may be a water-cooling plate 350, and the battery module 400 may be connected to the water-cooling plate 350 via a thermally conductive structural adhesive. The bottom plate may be an aluminum plate, which is more conducive to heat dissipation.

[0044] In order to prevent the structural adhesive from overflowing onto the weighing sensor assembly 100 or the thin film sensor assembly 200 during bonding and affecting the measurement accuracy, a glue blocking device can be provided on the top plate 310 and the second bottom plate 320, and the glue blocking device can be a glue blocking foam 360. The glue blocking foam 360 can be provided at a position of the battery module 400 close to the weighing sensor assembly 100 and close to the thin film sensor assembly 200.

[0045] A set of weighing sensor assemblies 100 is arranged between the end face of the battery cell at one end of the battery module 400 and the module fixing plate 340. For example, a set of weighing sensor assemblies 100 can be arranged between the left end face of the battery cell at the left end of the battery module 400 and the right side face of the module fixing plate 340 located on the left side.

[0046] Alternatively, a group of weighing sensor assemblies 100 are respectively arranged between the end faces of the battery cells at both ends of the battery module 400 and the module fixing plate 340, that is, a group of weighing sensor assemblies 100 are respectively arranged between the left end face of the battery cell at the left end of the battery module 400 and the right side face of the module fixing plate 340 located on the left side, and between the right end face of the battery cell at the right end of the battery module 400 and the left side face of the module fixing plate 340 located on the right side.

[0047] Meanwhile, a weighing sensor assembly 100 may be provided between any two battery cells in the battery module 400. Specifically, when the battery module 400 includes five battery cells, a weighing sensor assembly 100 may be provided at each of the four junctions of the five battery cells, or a weighing sensor assembly 100 may be provided at each of any three junctions, or a weighing sensor assembly 100 may be provided at each of any two junctions, or a weighing sensor assembly 100 may be provided at any one junction.

[0048] A preferred implementation is to arrange a weighing sensor assembly 100 between two battery cells in the middle.

[0049] The difference between the weighing sensor assembly 100 and the related art in which the weighing sensor 120 is used to detect the expansion force is that the weighing sensor assembly 100 provided in the embodiment of the utility model includes multiple force detection points, which can be distributed at various positions of the detection surface, rather than fixed point detection. In this way, the detection accuracy of the weighing sensor assembly 100 can be improved, so that the weighing sensor 120 can detect the expansion force of the battery module 400 in the X direction.

[0050] The thin film sensor assembly 200 is disposed between the weighing sensor assembly 100 and the end surface of the battery cell, and is used to detect the adhesion and flatness between the weighing sensor assembly 100 and the end surface of the battery cell during the initial cycle.

[0051] The battery expansion force detection device provided in the embodiment of the utility model adopts a thin film sensor assembly 200 for mutual verification of the weighing sensor assembly 100, verifies the difference between the test force value of the weighing sensor 120 detection assembly and the test force value of the thin film sensor assembly 200, and at the same time more accurately detects the expansion force and force conditions of the end battery cells and the middle battery cells of the battery module 400.

[0052] In some embodiments of the present invention, a load cell assembly 100 includes a sensor tooling and at least two load cells 120 .

[0053] The sensor fixture includes a first base plate 111, a first baffle plate 112 and a second baffle plate 113. The first baffle plate 112 and the second baffle plate 113 are slidably connected, and the sliding direction is perpendicular to the end face of the battery cell. After installation, the first baffle plate 112 is used to abut against the module fixing plate 340, and the second baffle plate 113 is used to contact the battery cell of the battery module 400. A plurality of weighing sensors 120 are distributed between the first baffle plate 112 and the second baffle plate 113.

[0054] When the battery module 400 expands during the charge and discharge cycle, the second baffle 113 and the first baffle 112 may move relative to the first bottom plate 111 along the X direction, thereby squeezing the weighing sensor 120 , and the weighing sensor 120 may detect the expansion force of the battery module 400 .

[0055] The multiple weighing sensors 120 are distributed at multiple points, and can detect the expansion force of the battery cells more accurately.

[0056] Specifically, a sliding assembly is provided between the first baffle plate 112, the second baffle plate 113 and the first bottom plate 111, and the sliding direction of the sliding assembly is along the X direction. The sliding assembly includes a stud 131, a ball 132 and a slide groove 133, the ball 132 is provided at the bottom of the stud 131, the slide groove 133 is provided on the first bottom plate 111, and the slide groove 133 extends along the X direction and is distributed along the Y direction.

[0057] Bolt holes for connecting with bolts are provided at the bottom of the first baffle 112 and the second baffle 113. The slide groove 133 is an arc-shaped groove. The ball 132 located at the bottom of the stud 131 is slidably connected to the arc-shaped groove, so that the first baffle 112 and the second baffle 113 can move in the X direction along the first base plate 111.

[0058] Furthermore, the radius of the arc-shaped groove is about 1.5 to 2 times the radius of the ball 132, and the depth is about half of the exposed portion of the ball 132. If the radius of the arc-shaped groove is too large, the limiting effect in the Y direction will be lost, and the bottom of the stud 131 will directly contact the first bottom plate 111, so that the ball 132 loses the function of reducing friction, resulting in the expansion force collection data being too small and invalid.

[0059] In order to prevent the first baffle 112 and the second baffle 113 from moving along the Y direction, upwardly extending protrusions are further provided on the top surfaces of both ends of the first base plate 111 along the Y direction, and the distance between the opposite surfaces of the two protrusions is equal to the length of the first baffle 112 and the second baffle 113 along the Y direction.

[0060] Furthermore, in order to make the first baffle 112 and the second baffle 113 move strictly along the X direction, a guide assembly is further provided between the first baffle 112 and the second baffle 113. The guide assembly is composed of a bushing 141, a set screw 142 and a guide column 143. The bushing 141 is fixed to the first baffle 11 by the set screw 142. One end of the guide column 143 is connected to the bushing 141 and will not fall out of the bushing 141. The other end of the guide column 143 is connected to the second baffle 113 and fixed by bolts, so that the first baffle 112 and the second baffle 113 form a whole. When the first baffle 112 and the second baffle 113 move, the guide column 143 moves along the X direction in the bushing 141, so that the first baffle 112 and the second baffle 113 can only move along the X direction.

[0061] In this embodiment, the weighing sensor assembly 100 is provided with four guide assemblies, and the number of guide assemblies can also be selected according to the size of the sensor tooling. The bushing 141 and the guide column 143 need to be relatively smooth to reduce the influence of friction on the expansion force.

[0062] Since the weighing sensor assembly 100 is made of metal and dissipates heat quickly, a heat insulation pad 500 is provided at the contact surface between the battery cell and the weighing sensor assembly 100 to provide a certain heat preservation effect and prevent abnormal battery cycle caused by temperature loss.

[0063] The thin film sensor assembly 200 is arranged between the battery cell and the thermal insulation pad 500, and is used for initial cycle detection of the adhesion and flatness between the weighing sensor 120 and the large surface of the battery.

[0064] In addition, a handle 600 is provided on the second bottom plate 320 , and the handle 600 is connected to the second bottom plate 320 by bolts, so as to facilitate carrying.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A battery expansion force detection device, characterized in that: include: A mounting frame, in which a battery module (400) is mounted; At least two groups of weighing sensor assemblies (100), the weighing sensor assemblies (100) being arranged between the end faces of the battery cells at one end or both ends of the battery module (400) and the mounting frame, the weighing sensor assemblies (100) being arranged between at least two adjacent battery cells in the battery module (400), and the weighing sensor assemblies (100) having a plurality of force detection points; A thin film sensor assembly (200) is provided between the weighing sensor assembly (100) and the end surface of the battery cell.

2. The battery expansion force detection device according to claim 1, characterized in that: The weighing sensor assembly (100) comprises: A sensor tooling comprises a first base plate (111), a first baffle plate (112) and a second baffle plate (113), wherein the first baffle plate (112) and the second baffle plate (113) are slidably connected, and a sliding direction is perpendicular to an end face of the battery cell; At least two weighing sensors (120), wherein a plurality of the weighing sensors (120) are distributed between the first baffle (112) and the second baffle (113).

3. The battery expansion force detection device according to claim 2, characterized in that: A guide assembly is also provided between the first baffle plate (112) and the second baffle plate (113), and the guide assembly is used to restrict the first baffle plate (112) and the second baffle plate (113) to move only in a direction perpendicular to the end surface of the battery cell.

4. The battery expansion force detection device according to claim 1, characterized in that: A heat insulation pad (500) is also provided between the battery cell and the weighing sensor (120).

5. The battery expansion force detection device according to claim 4, characterized in that: The thin film sensor assembly (200) is arranged between the thermal insulation pad (500) and the battery cell.

6. The battery expansion force detection device according to claim 1, characterized in that: The mounting frame comprises: A frame body, the frame body comprising a top plate (310), a second bottom plate (320), and two end plates (330) arranged between the top plate (310) and the second bottom plate (320); Two module fixing plates (340), the two module fixing plates (340) are arranged between the two end plates (330), and the two module fixing plates (340) are used to clamp at both ends of the battery module (400).

7. The battery expansion force detection device according to claim 6, characterized in that: A heat dissipation plate is also provided on a side of the second bottom plate (320) close to the top plate (310).

8. The battery expansion force detection device according to claim 7, characterized in that: The heat dissipation plate is a water cooling plate (350).

9. The battery expansion force detection device according to claim 6, characterized in that: The battery module (400) is connected to the top plate (310) and the second bottom plate (320) by means of structural adhesive. The top plate (310) and the second bottom plate (320) are also provided with adhesive blocking devices. The adhesive blocking devices are located between the battery module (400) and the weighing sensor assembly (100), and between the battery module (400) and the thin film sensor assembly (200).

10. The battery expansion force detection device according to claim 6, characterized in that: The second bottom plate (320) is also provided with a handle (600).

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