Assembly process of lithium battery module

Abstract

The invention provides an assembling process of a lithium battery module, which comprises the following steps: step 1 to step 9, conveying a battery cell module to the upper part of a liquid cooling plate through a conveying device for assembling, meanwhile, conveying a module base to an assembling station in the step 1 by the conveying device, gluing the upper part of the liquid cooling plate, hoisting the battery cell module to separate the battery cell module from the module base, and assembling the battery cell module. The battery cell module is moved to the position above the glued liquid cooling plate to be pressed and assembled, detection is conducted multiple times during assembly, the quality of the lithium battery PACK is guaranteed, the yield is improved, meanwhile, manual transportation assembly and intelligent machining are not needed, and the assembly efficiency is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery assembly processing, and more specifically, to an assembly process for a lithium battery module. Background Art

[0002] Lithium battery is a type of battery that uses lithium metal or lithium alloy as positive / negative electrode material and non-aqueous electrolyte solution. In the early days, lithium battery PACK mainly refers to the processing and assembly of lithium-ion battery packs, which mainly combines lithium cells, lithium-ion battery protection boards, battery connectors, etc. into products required by customers through battery PACK process. With the gradual development of new energy vehicles, smart phones, laptops and other products in recent years, the demand for lithium batteries has gradually increased; the energy density of lithium-ion batteries has gradually increased. The traditional lithium battery PACK process only uses simple packaging for batteries, and there are no strict requirements, resulting in many unqualified lithium batteries.

[0003] The technology closest to the existing one is, Publication No.: CN111463393A, a battery pack PACK method, the production process of lithium battery PACK: battery cell appearance, thickness inspection → battery cell test → 3M double-sided tape on battery cell → bottom film on battery cell → nickel sheet on positive and negative electrodes of battery cell → spot welding nickel sheet on battery cell → spot welding protection plate → welding effect inspection → bracket sticking → initial performance inspection → finished product performance test → label paper alignment → label packaging → full appearance inspection → high temperature aging → load test → tape installation → box packing.

[0004] The existing PACK method has high labor intensity, low assembly efficiency, and low assembly precision, and cannot meet higher assembly requirements.

[0005] In view of this, the present invention provides an assembly process for a lithium battery module with high assembly yield and high assembly efficiency. Summary of the invention

[0006] The purpose of the present invention is to provide an assembly process for a lithium battery module with high assembly yield and high assembly efficiency.

[0007] A lithium battery module assembly process, characterized in that it comprises the following steps:

[0008] Step 1: Single cell feeding inspection, unqualified products are automatically removed and rejected;

[0009] Step 2: Stack the cells together, apply epoxy sheets to the contact surfaces of each cell with the adjacent cells, then place the cells with the poles facing upwards, and squeeze one side of the cell with the epoxy sheet against the opposite side of the adjacent cell with the epoxy sheet to form a cell module and tape it;

[0010] Step 3: Laser coding, after taping, it is transported to the next station, and the battery cells are scanned in turn, and then the end plate of the battery cell module is laser-coded and read;

[0011] Step 4: Clean the pole and measure the height. After laser coding, the battery cell module is transported to the next station for automatic laser cleaning of the pole. The height and position of the pole are detected while cleaning. The modules with unqualified pole height are transported to the next station for offline.

[0012] Step 5: CCS welding and inspection. Perform CCS welding on the battery module and conduct post-welding inspection. During CCS welding, the input power is 3800w-4000w, the welding speed is 100-120mm / s, and the welding height is 33.9-34.1cm. If it meets the welding inspection requirements, proceed to step 6. If not, proceed to inspection.

[0013] Step 6: Internal resistance test and module EOL test of the battery module. Perform automatic total voltage internal resistance test and module EOL test on the welded battery module. If the automatic total voltage internal resistance test and module EOL test are passed, proceed to step 7. If not, perform inspection.

[0014] Step 7: The cell module is transported to the top of the liquid cooling plate by the conveying device for assembly. At the same time, the conveying device returns the module base to the assembly station in step 1, wherein glue is applied on the top of the liquid cooling plate, the cell module is hoisted to separate it from the module base, and the cell module is moved to the top of the glue-coated liquid cooling plate for press assembly;

[0015] Step 8: Assemble the battery cell module into PACK;

[0016] Step 9: Perform a secondary EOL test on the finished PACK assembled product. If it meets the automatic total pressure internal resistance test and the module EOL test, the processing is completed. If it fails, an inspection is performed.

[0017] In some embodiments, in step 1, the single cells are arranged in order on a loading rack, and the poles of the cells are placed upward.

[0018] Furthermore, in step one, the four corners of the loading rack where the battery cells are placed are photographed by a CCD device to record the position of each battery cell, and the position of each battery cell is transmitted to the control panel to facilitate the subsequent grabbing of the battery cells.

[0019] Furthermore, in step one, a single battery cell is clamped and rotated 90 degrees, and is laid flat on a loading conveyor belt in turn, with the poles of the battery cell facing outwards, for transportation to a detection unit.

[0020] Furthermore, in step one, the robot grasps the side wall of a single battery cell and transports it horizontally to the internal resistance and voltage detection device, tests the internal resistance and voltage of the single battery in turn, removes defective products, and records the detection information of each battery cell by scanning the QR code unique to each battery cell through a scanning mechanism.

[0021] Furthermore, in step one, during the detection process, if only the positive and negative poles of the battery cell are wrong, only a 360-degree rotation correction is required.

[0022] In some embodiments, in step two, the battery cell with the epoxy board is rotated 90 degrees so that the pole of the battery cell faces upward, and is placed on a transition station. The robot arm is released, and the battery cell is grabbed again and placed on a conveyor belt. The battery cell is conveyed to an extrusion device for left and right extrusion and front and back pushing. Subsequently, electrical connection boards are added to the two outermost sides to form a battery cell module, and the battery cell module is manually covered with a steel belt after reaching the stroke of the steel belt.

[0023] Furthermore, the battery cell module is composed of 7-13 battery cells.

[0024] In some embodiments, in step three, the battery cell module with the sleeve is transported together with the backing plate, and the robot enters the bottom of the battery cell module. The insertion position of the robot is the gap between two adjacent battery cells, and the battery cell module is transported to the laser coding mechanism for laser coding of the battery cell module.

[0025] In some embodiments, in step four, the cleaning parameters for automatic pole cleaning include cleaning height, cleaning speed, and cleaning power. The cleaning height is 33.5-34 cm, the cleaning speed is 1000-1400 mm / s, and the cleaning power is 80-120 w.

[0026] Furthermore, the sorting parameters are voltage: 3.29V-3.3V internal resistance: 0-0.3mΩ.

[0027] In some embodiments, in step five, during CCS welding, the welding speed is 90 mm / s, the idle speed is 2000 mm / s, the power is 65%, the waveform number is 15, the frequency is 85 Hz, the duty cycle is 100%, the on-delay is 60 microseconds, the off-delay is 10 microseconds, the corner delay is 50 microseconds, and the red light speed is 500 mm / s.

[0028] In some embodiments, in step five, a post-weld visual inspection is performed on the battery cell module to ensure that the weld has no offset, black holes, excess height less than 1mm, weld width>3mm, and a gap between the bar and the pole is less than 0.3mm. A pry bar is used to pry the welded bar to ensure that the bar does not shake. The post-weld inspection parameters include weld width, excess height, bar gap, pits, and track diameter. The weld width is 3mm-6mm, the excess height is 0-1mm, the bar gap is 0-0.3mm, the pits are -0.5mm-0mm, and the track diameter is 10mm.

[0029] In some embodiments, in step six, an automatic total voltage internal resistance test is performed on the welded battery cell module, and a voltage internal resistance testing device is used to test the welded battery cell module. The total voltage internal resistance setting parameters include total voltage and internal resistance. The total voltage is 42.77V-42.9V, and the internal resistance is <4mΩ.

[0030] In some embodiments, in step six, an automatic total voltage internal resistance test is performed on the welded battery cell module, and a voltage internal resistance testing device is used to test the welded battery cell module. The total voltage internal resistance setting parameters include total voltage and internal resistance. The total voltage is 42.77V-42.9V, and the internal resistance is <4mΩ.

[0031] In some embodiments, in step seven, the glue coating is performed on the top of the liquid cooling plate. Specifically, a first glue strip is provided at both ends of the liquid cooling plate, three second glue strips are provided in parallel and spaced apart between adjacent first glue strips, and glue coating areas are formed between adjacent first glue strips and second glue strips. AB structural glue strips are coated in the glue coating areas, and the AB structural glue strips are wave-folded.

[0032] Furthermore, the gluing area is coated with AB structural adhesive strips, and the time from the start of gluing to the pressing and assembling needs to be less than 30 minutes.

[0033] Beneficial effects of the present invention: The present invention proposes an assembly process for a lithium battery module. Through steps one to nine, the battery cell module is transported to the top of the liquid cooling plate by a conveying device for assembly. At the same time, the conveying device returns the module base to the assembly station in step one, glue is applied on the top of the liquid cooling plate, the battery cell module is hoisted to be separated from the module base, and the battery cell module is moved to the top of the glue-coated liquid cooling plate for press assembly. During assembly, multiple inspections are performed to ensure the quality of the lithium battery PACK and improve the yield rate. At the same time, there is no need for manual transportation and assembly, and intelligent processing is used to greatly improve the assembly efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic diagram of the assembly process of a lithium battery module of the present application.

[0035] Main component symbols

[0036] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0037] The following examples are described to assist the understanding of the present application, and the examples are not and should not be interpreted in any way as limiting the scope of protection of the present application.

[0038] In the following description, those skilled in the art will recognize that throughout this discussion, components may be described as separate functional units (which may include sub-units), but those skilled in the art will recognize that various components or portions thereof may be divided into separate components or may be integrated together (including within a single system or component).

[0039] At the same time, the connections between components or systems are not intended to be limited to direct connections, rather, the data between these components may be modified, reformatted, or otherwise changed by intermediate components. In addition, additional or fewer connections may be used. It should also be noted that the terms "coupled," "connected," or "input" should be understood to include direct connections, indirect connections through one or more intermediate devices, and wireless connections.

[0040] Embodiment 1:

[0041] like Figure 1 The figure is a schematic diagram of the process of assembling a lithium battery module of the present application.

[0042] A lithium battery module assembly process, characterized in that it comprises the following steps:

[0043] Step 1: Single cell feeding inspection, unqualified products are automatically removed and rejected;

[0044] Step 2: Stack the cells together, apply epoxy sheets to the contact surfaces of each cell with the adjacent cells, then place the cells with the poles facing upwards, and squeeze one side of the cell with the epoxy sheet against the opposite side of the adjacent cell with the epoxy sheet to form a cell module and tape it;

[0045] Step 3: Laser coding, after taping, it is transported to the next station, and the battery cells are scanned in turn, and then the end plate of the battery cell module is laser-coded and read;

[0046] Step 4: Clean the pole and measure the height. After laser coding, the battery cell module is transported to the next station for automatic laser cleaning of the pole. The height and position of the pole are detected while cleaning. The modules with unqualified pole height are transported to the next station for offline.

[0047] Step 5: Perform CCS welding on the battery module and conduct post-welding inspection. During CCS welding, the input power is 3800w-4000w, the welding speed is 100-120mm / s, and the welding height is 33.9-34.1cm. If the welding inspection meets the requirements, proceed to step 6. If not, conduct an inspection.

[0048] Step 6: Perform automatic total voltage internal resistance test and module EOL test on the welded battery module. If the test is successful, proceed to step 7. If not, perform inspection.

[0049] Step 7: The cell module is transported to the top of the liquid cooling plate by the conveying device for assembly. At the same time, the conveying device returns the module base to the assembly station in step 1, wherein the liquid cooling plate is coated with glue, the cell module is hoisted to separate it from the module base, and the cell module is moved to the top of the liquid cooling plate coated with glue for pressing and assembly.

[0050] Step 8: Assemble the battery cell module into PACK.

[0051] Step 9: Perform a secondary EOL test on the product that has completed PACK assembly, and then the processing is completed. If it is unsuccessful, conduct an inspection.

[0052] In step one, the single cells are arranged in order on the loading rack, and the poles of the cells are placed upwards. The four corners of the loading rack where the cells are placed are photographed by means of a CCD device to record the position of each cell and transmit the position of each cell to the control panel for the convenience of subsequent grabbing of the cells. After the single cell is clamped, it is rotated 90 degrees and laid flat on the loading conveyor belt in turn. The poles of the cells are transported outwards to the detection unit. The manipulator grabs the side wall of the single cell and transports it horizontally to the internal resistance and voltage detection device. The internal resistance and voltage of the single battery are tested in turn, and defective products are removed. The scanning mechanism scans the unique QR code of each cell to record the detection information of each cell. During the detection process, if only the positive and negative poles of the poles of the cell are wrong, only a 360-degree rotation is required to correct it.

[0053] In step two, the battery cell with epoxy board is rotated 90 degrees so that the pole of the battery cell faces upwards, and placed on the transition station. The robot arm is released, and the battery cell is grabbed again and placed on the conveyor belt. It is conveyed to the extrusion device for left and right extrusion and pushed front and back. Then, the electrical connection plates are added to the two outermost sides to form a battery module. After reaching the stroke of the steel belt, the battery module is manually covered with steel belt. The battery module consists of 7-13 battery cells.

[0054] In step three, the battery cell module with the sleeve is transported together with the backing plate, and the robot enters the bottom of the battery cell module. The insertion position of the robot is the gap between two adjacent battery cells, and the battery cell module is transported to the laser coding mechanism for laser coding of the battery cell module.

[0055] In step 4, the cleaning parameters for automatic pole cleaning include cleaning height, cleaning speed, and cleaning power. The cleaning height is 33.5-34cm, the cleaning speed is 1000-1400mm / s, the cleaning power is 80-120w, and the sorting parameters are voltage: 3.29V-3.3V, and internal resistance: 0-0.3mΩ.

[0056] In step five, CCS welding is specifically as follows: welding speed is 90 mm / s, idle speed is 2000 mm / s, power is 65%, waveform number is 15, frequency is 85 Hz, duty cycle is 100%, light on delay is 60 microseconds, light off delay is 10 microseconds, corner delay is 50 microseconds, red light speed is 500 mm / s, and the battery cell module is visually inspected after welding to ensure that the weld has no offset, black holes, excess height is less than 1 mm, weld width is greater than 3 mm, and the gap between the bar and the pole is less than 0.3 mm. Use a pry bar to pry the welded bar, and the bar does not shake. The post-weld inspection parameters include weld width, excess height, bar gap, pits, and track diameter. The weld width is 3mm-6mm, the excess height is 0-1mm, the bar gap is 0-0.3mm, the pit is -0.5mm-0mm, and the track diameter is 10mm.

[0057] In step six, an automatic total voltage internal resistance test is performed on the welded battery module. A voltage internal resistance test device is used to test the welded battery module. The total voltage internal resistance setting parameters include total voltage and internal resistance. The total voltage is 42.77V-42.9V, and the internal resistance is <4mΩ. An automatic total voltage internal resistance test is performed on the welded battery module. A voltage internal resistance test device is used to test the welded battery module. The total voltage internal resistance setting parameters include total voltage and internal resistance. The total voltage is 42.77V-42.9V, and the internal resistance is <4mΩ.

[0058] In step seven, glue is applied on the top of the liquid cooling plate. Specifically, a first glue strip is provided at both ends of the liquid cooling plate, three second glue strips are provided in parallel with each other between adjacent first glue strips, and a glue coating area is formed between adjacent first glue strips and second glue strips. The glue coating area is coated with an AB structural glue strip, and the AB structural glue strip is a wave-folded type. The glue coating area is coated with an AB structural glue strip, and the time from the start of glue coating to the pressing and assembling time needs to be less than 30 minutes.

[0059] Beneficial effects of the present invention: The present invention proposes an assembly process for a lithium battery module. Through steps one to nine, the battery cell module is transported to the top of the liquid cooling plate by a conveying device for assembly. At the same time, the conveying device returns the module base to the assembly station in step one, glue is applied on the top of the liquid cooling plate, the battery cell module is hoisted to be separated from the module base, and the battery cell module is moved to the top of the glue-coated liquid cooling plate for press assembly. During assembly, multiple inspections are performed to ensure the quality of the lithium battery PACK and improve the yield rate. At the same time, there is no need for manual transportation and assembly, and intelligent processing is used to greatly improve the assembly efficiency.

[0060] Although the present application has disclosed multiple aspects and embodiments, other aspects and embodiments will be obvious to those skilled in the art, and several modifications and improvements may be made without departing from the concept of the present application, all of which belong to the protection scope of the present application. The multiple aspects and embodiments disclosed in the present application are only for illustration and are not intended to limit the present application. The actual protection scope of the present application shall be subject to the claims.

Claims

1. A lithium battery module assembly process, characterized in that: The following steps are involved: Step 1: Single cell feeding inspection, unqualified products are automatically removed and rejected; Step 2: Stack the cells together, apply epoxy sheets to the contact surfaces of each cell with the adjacent cells, then place the cells with the poles facing upwards, and squeeze one side of the cell with the epoxy sheet against the opposite side of the adjacent cell with the epoxy sheet to form a cell module and tape it; Step 3: Laser coding, after taping, it is transported to the next station, and the battery cells are scanned in turn, and then the end plate of the battery cell module is laser-coded and read; Step 4: Clean the pole and measure the height. After laser coding, the battery cell module is transported to the next station for automatic laser cleaning of the pole. The height and position of the pole are detected while cleaning. The modules with unqualified pole height are transported to the next station for offline. Step 5: CCS welding and inspection. Perform CCS welding on the battery module and conduct post-welding inspection. During CCS welding, the input power is 3800w-4000w, the welding speed is 100-120mm / s, and the welding height is 33.9-34.1cm. If it meets the welding inspection requirements, proceed to step 6. If not, proceed to inspection. Step 6: Internal resistance test and module EOL test of the battery module. Perform automatic total voltage internal resistance test and module EOL test on the welded battery module. If the automatic total voltage internal resistance test and module EOL test are passed, proceed to step 7. If not, perform inspection. Step 7: The cell module is transported to the top of the liquid cooling plate by the conveying device for assembly. At the same time, the conveying device returns the module base to the assembly station in step 1, wherein glue is applied on the top of the liquid cooling plate, the cell module is hoisted to separate it from the module base, and the cell module is moved to the top of the glue-coated liquid cooling plate for press assembly; Step 8: Assemble the battery cell module into PACK; Step 9: Perform a secondary EOL test on the finished PACK assembled product. If it meets the automatic total pressure internal resistance test and the module EOL test, the processing is completed. If it fails, an inspection is performed.

2. The assembly process of the lithium battery module according to claim 1, characterized in that: In step 1, the single cells are arranged in order on a loading rack, and the poles of the cells are placed upward.

3. The assembly process of the lithium battery module according to claim 1, characterized in that: In step one, the four corners of the loading rack where the battery cells are placed are photographed by a CCD device to record the position of each battery cell, and the position of each battery cell is transmitted to the control panel to facilitate the subsequent grabbing of the battery cells.

4. The assembly process of the lithium battery module according to claim 1, characterized in that: In step one, a single battery cell is clamped and rotated 90 degrees, and is laid flat on a loading conveyor belt in turn, with the poles of the battery cell facing outwards, for transportation to a testing unit.

5. The assembly process of the lithium battery module according to claim 1, characterized in that: In step one, the robot grabs the side wall of a single battery cell and transports it horizontally to the internal resistance and voltage detection device, tests the internal resistance and voltage of the single battery in turn, removes defective products, and records the detection information of each battery cell by scanning the unique QR code of each battery cell through a scanning mechanism.

6. The lithium battery module assembly process according to claim 1, characterized in that: In step 1, during the detection process, if only the positive and negative poles of the battery cell are wrong, only a 360-degree rotation is required to correct it.

7. The lithium battery module assembly process according to claim 1, characterized in that: In step two, the battery cell with epoxy board is rotated 90 degrees so that the pole of the battery cell faces upwards, and placed on the transition station. The robot arm is released, and the battery cell is grabbed again and placed on the conveyor belt. It is conveyed to the extrusion device for left and right extrusion and pushed front and back. Then, the electrical connection plates are added to the two outermost sides to form a battery cell module. After reaching the stroke of the steel belt, the battery cell module is manually covered with steel belt.

8. The lithium battery module assembly process according to claim 1, characterized in that: In step three, the battery cell module with the sleeve is transported together with the backing plate, and the robot enters the bottom of the battery cell module. The insertion position of the robot is the gap between two adjacent battery cells, and the battery cell module is transported to the laser coding mechanism for laser coding of the battery cell module.

9. The lithium battery module assembly process according to claim 1, characterized in that: In step 4, the cleaning parameters for automatic pole cleaning include cleaning height, cleaning speed, and cleaning power. The cleaning height is 33.5-34 cm, the cleaning speed is 1000-1400 mm / s, and the cleaning power is 80-120 w.

10. The lithium battery module assembly process according to claim 1, characterized in that: In step five, the specific conditions for CCS welding are as follows: welding speed is 90 mm / s, idle speed is 2000 mm / s, power is 65%, waveform number is 15, frequency is 85 Hz, duty cycle is 100%, light on delay is 60 microseconds, light off delay is 10 microseconds, corner delay is 50 microseconds, and red light speed is 500 mm / s. In step five, the battery cell module is visually inspected after welding to ensure that there is no offset in the weld, black hole, excess height is less than 1 mm, weld width is greater than 3 mm, and the gap between the bar and the pole is less than 0.3 mm. A pry bar is used to pry the welded bar to ensure that the bar does not shake. The post-weld inspection parameters include weld width, excess height, bar gap, pits, and track diameter. The weld width is 3mm-6mm, the excess height is 0-1mm, the bar gap is 0-0.3mm, the pits are -0.5mm-0mm, and the track diameter is 10mm.

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