Lithium battery PACK method

Abstract

The invention provides a lithium battery PACK method which comprises the following steps: step 1 to step 6, a battery cell module is conveyed to a position above a liquid cooling plate through a conveying device to be assembled, meanwhile, a module base is further conveyed to an assembling station in the step 1 by the conveying device, the position above the liquid cooling plate is coated with glue, the battery cell module is hoisted to be separated from the module base, and the battery cell module and the liquid cooling plate are assembled. 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 a lithium battery PACK method. 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 a lithium battery PACK method with high assembly yield and high assembly efficiency. Summary of the invention

[0006] The purpose of the present invention is to provide a lithium battery PACK method with high assembly yield and high assembly efficiency.

[0007] A lithium battery PACK method, characterized by comprising the following steps:

[0008] Step 1: Multiple single cells are assembled into a cell module, wherein a module base is provided at the bottom of the cell module, and the module base is used to carry the cell module. After multiple single cells are assembled into a cell module, each cell in the group is scanned for verification. If successful, the module QR code is output, which is printed by a printer and pasted to the module end plate or laser printed on the module end plate. If unsuccessful, an inspection is performed;

[0009] Step 2: Scan the cell module and assemble the CCS harness. Scanning the cell module is to scan the cell module QR code and compare it with the module base end plate code to determine whether the cell module is bound to the module base. If the binding is successful, proceed to step 3. If not, perform an inspection.

[0010] Step 3: 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 4. If not, proceed to inspection.

[0011] Step 4: Perform automatic total voltage internal resistance test and module-level EOL test on the welded battery module. If the test is successful, proceed to step 5. If not, perform inspection.

[0012] Step 5: 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;

[0013] Step 6: Assemble the battery cell module into PACK;

[0014] Step 7: Perform PACK-level EOL test on the assembled PACK. If it meets the PACK-level EOL test, the processing is completed. If it fails, an inspection is performed.

[0015] In some embodiments, in step three, 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 light-on delay is 60 microseconds, the light-off delay is 10 microseconds, the corner delay is 50 microseconds, and the red light speed is 500 mm / s.

[0016] In some embodiments, before step one, single cell selection, automatic polarity detection, and automatic pole cleaning are sequentially provided. The single cell selection is used to select a cell material body that meets the processing parameters, the automatic polarity detection is used to set the polarity of the cell module, and the automatic pole cleaning is used to clean the cell pole to facilitate subsequent CCS welding.

[0017] Furthermore, the selection of a single battery cell includes battery cell appearance inspection, battery cell sorting, battery cell stacking, battery cell extrusion, and manual code scanning, wherein the battery cell appearance inspection is to perform an appearance inspection on the battery cell to check whether the battery cell blue film is damaged, whether the blue film has foreign matter, whether the pole is dirty, and whether the explosion-proof valve is damaged; the battery cell sorting is to place the battery cells that have passed the visual inspection during the battery cell appearance inspection on the assembly line tray, and use a sorting machine to automatically sort the single battery cells; the battery cell stacking and battery cell extrusion are to stack and extrude the single battery cells after the sorting is completed to obtain a battery cell module, and collect the battery cell codes from left to right for the battery cell module; the battery cell code of the battery cell module generates a module base QR code, and the module base QR code is pasted on the module base.

[0018] Furthermore, the cleaning parameters during 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, and the cleaning power is 80-120w.

[0019] Furthermore, the sorting parameters are voltage: 3.29V-3.3V internal resistance: 0-0.3mΩ.

[0020] In some embodiments, in step three, 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.

[0021] In some embodiments, in step three, 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.

[0022] In some embodiments, in step five, 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 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 applied in the glue coating areas, and the AB structural glue strips are wave-folded.

[0023] 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.

[0024] In some embodiments, in step six, the battery cell module is PACK assembled, and the PACK assembly includes the installation of the positive and negative sockets of the battery cell module, the installation of the communication port, the installation of the explosion-proof valve, the installation of the copper plate, and the installation of the BMU.

[0025] Furthermore, the BMU detection battery management unit is installed specifically by setting a BMU bracket on the side of the liquid cooling plate of the battery cell module, and the BMU detection battery management unit is arranged in the BMU bracket.

[0026] Beneficial effects of the present invention: The present invention proposes a lithium battery PACK method, through steps one to six, the battery cell module is transported to the top of the liquid cooling plate by a conveying device for assembly, and 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, and multiple inspections are performed during assembly 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

[0027] Figure 1 A schematic diagram of a lithium battery PACK method of the present application.

[0028] Main component symbols

[0029] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0030] 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.

[0031] 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).

[0032] 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.

[0033] Embodiment 1:

[0034] like Figure 1Shown is a flow chart of a lithium battery PACK method of the present application.

[0035] A lithium battery PACK method, characterized by comprising the following steps:

[0036] Step 1: Multiple single cells are assembled into a cell module, wherein a module base is provided at the bottom of the cell module, and the module base is used to carry the cell module. After multiple single cells are assembled into a cell module, each cell in the group is scanned for verification. If successful, the module QR code is output, which is printed by a printer and pasted to the module end plate or laser printed on the module end plate. If unsuccessful, an inspection is performed;

[0037] Step 2: Scan the cell module and assemble the CCS harness. Scanning the cell module is to scan the cell module QR code and compare it with the module base end plate code to determine whether the cell module is bound to the module base. If the binding is successful, proceed to step 3. If not, perform an inspection.

[0038] Step 3: 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 4. If not, proceed to inspection.

[0039] Step 4: Perform automatic total voltage internal resistance test and module-level EOL test on the welded battery module. If the test is successful, proceed to step 5. If not, perform inspection.

[0040] Step 5: 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;

[0041] Step 6: Assemble the battery cell module into PACK;

[0042] Step 7: Perform PACK-level EOL test on the assembled PACK. If it meets the PACK-level EOL test, the processing is completed. If it fails, an inspection is performed.

[0043] In step three, during CCS welding, the specific conditions are: welding speed 90 mm / s, idle speed 2000 mm / s, power 65%, waveform number 15, frequency 85 Hz, duty cycle 100%, on-delay 60 microseconds, off-delay 10 microseconds, corner delay 50 microseconds, and red light speed 500 mm / s.

[0044] Before step one, single cell selection, automatic polarity detection, and automatic pole cleaning are sequentially provided. Single cell selection is used to select cell material bodies that meet processing parameters, automatic polarity detection is used to set the polarity of the cell module, and automatic pole cleaning is used to clean the cell poles for subsequent CCS welding.

[0045] The selection of a single battery cell includes battery cell appearance inspection, battery cell sorting, battery cell stacking, battery cell extrusion, and manual code scanning. Among them, the battery cell appearance inspection is to perform an appearance inspection on the battery cell to check whether the battery cell blue film is damaged, whether there are foreign objects on the blue film, whether the pole is dirty, and whether the explosion-proof valve is damaged. The battery cell sorting is to place the battery cells that have passed the visual inspection during the battery cell appearance inspection on the assembly line tray, and use a sorting machine to automatically sort the single battery cells. Battery stacking and battery cell extrusion are to stack and extrude the single battery cells after the sorting is completed to obtain a battery cell module, and collect the battery cell codes from left to right for the battery cell module. The battery code of the battery cell module generates a module base QR code, and the module base QR code is pasted on the module base.

[0046] 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, and the cleaning power is 80-120w.

[0047] The sorting parameters are voltage: 3.29V-3.3V internal resistance: 0-0.3mΩ.

[0048] Carry out visual inspection on the battery cell module after welding to ensure that there is no offset in the weld, black holes, excess height less than 1mm, weld width>3mm, and the gap between the bar and the pole is less than 0.3mm. Use a pry bar to pry the welded bar to check 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.

[0049] In step three, the welded battery cell module is automatically tested for total voltage and internal resistance using a voltage internal resistance test device. The total voltage and internal resistance setting parameters include total voltage and internal resistance. The total voltage is 42.77V-42.9V, and the internal resistance is <4mΩ.

[0050] In step three, the welded cell module is subjected to module-level EOL test. The module-level EOL test includes insulation detection, continuity detection, module size detection, module appearance detection, and module-ACR detection. The insulation detection is performed on the positive electrode to the end plate and the negative electrode to the end plate. The detection voltage is 1500VDC, the voltage stabilization test time is 60s, and the insulation detection meets the standard parameters of ≥500mΩ; the continuity test meets the standard parameters of the module total voltage of 42.77V-42.9V; the module size detection includes module length, module installation center distance (X direction), module width, module installation center distance (Y direction), module height, and module bottom to end plate bottom. The standard parameter of module length is 994.45±1 .0mm, the standard parameter of module installation center distance (X direction) is 977.45±0.5mm, the standard parameter of module width is 177.5±1.0mm, the standard parameter of module installation center distance (Y direction) is 159±0.5mm, the standard parameter of module height is 216±1mm, and the standard parameter from the bottom of the module to the bottom of the end plate is 17.3±0.3mm; the standard parameter for low-voltage connector pin inspection is visual inspection to ensure that the pin is not skewed; the standard parameter for steel strip insulation layer inspection is visual inspection to ensure that there is no damage or exposed metal; the standard parameter for the output pole is that there is no foreign matter or blockage in the output pole bolt hole; the module-ACR test is to measure the ACR between the total positive and total negative of the battery cross group, and the standard parameter of ACR is ≤7mΩ.

[0051] In step four, 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 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 applied in the glue coating areas, and the AB structural glue strips are wave-folded.

[0052] The gluing area is coated with AB structural adhesive strips, and the time from the start of gluing to the pressing and assembly needs to be less than 30 minutes.

[0053] In step 4, the assembled PACK is subjected to a PACK-level EOL test. The PACK-level EOL test includes insulation impedance detection, withstand voltage detection, water cooling system air tightness detection, and box air tightness detection. The insulation impedance detection is performed on the positive and negative poles to the shell, the detection voltage is 1500VDC, and the voltage stabilization test time is 30s; the withstand voltage detection is performed on the positive and negative poles to the shell, the detection voltage is 4400VDC, and the voltage stabilization test time is 60s; the water cooling system air tightness detection is specifically to charge the electric box with a maximum pressure of 350kpa, maintain the pressure at 350±5kpa, and last for 60s, and measure, the measurement time is 60s, and when the test result is ≤65Pa / min; the box air tightness detection is specifically to charge the electric box with a maximum pressure of 3.5kpa, maintain the pressure at 3.5±0.5kpa, and last for 60s, and measure, the measurement time is 60s, and when the test result is ≤60Pa / min

[0054] In step six, the battery cell module is PACK assembled, which includes the installation of the positive and negative sockets of the battery cell module, the communication port, the explosion-proof valve, the copper plate, and the BMU.

[0055] The BMU detection battery management unit is installed specifically by setting a BMU bracket on the side of the liquid cooling plate of the battery cell module, and the BMU detection battery management unit is arranged in the BMU bracket.

[0056] Beneficial effects of the present invention: The present invention proposes a lithium battery PACK method, through steps one to six, the battery cell module is transported to the top of the liquid cooling plate by a conveying device for assembly, and 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, and multiple inspections are performed during assembly 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.

[0057] 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 PACK method, characterized in that: The following steps are involved: Step 1: Multiple single cells are assembled into a cell module, wherein a module base is provided at the bottom of the cell module, and the module base is used to carry the cell module. After multiple single cells are assembled into a cell module, each cell in the group is scanned for verification, and if successful, the module QR code is output, which is printed by a printer and pasted to the module end plate or laser printed on the module end plate. If unsuccessful, check; Step 2: Scan the cell module and assemble the CCS harness. Scanning the cell module is to scan the cell module QR code and compare it with the module base end plate code to determine whether the cell module is bound to the module base. If the binding is successful, proceed to step 3. If not, perform an inspection. Step 3: 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 4. If not, proceed to inspection. Step 4: Perform automatic total voltage internal resistance test and module-level EOL test on the welded battery module. If the test is successful, proceed to step 5. If not, perform inspection. Step 5: 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 6: Assemble the battery cell module into PACK; Step 7: Perform PACK-level EOL test on the assembled PACK. If it meets the PACK-level EOL test, the processing is completed. If it fails, an inspection is performed.

2. The lithium battery PACK method according to claim 1, characterized in that: In step three, during CCS welding, the specific conditions are: welding speed 90 mm / s, idle speed 2000 mm / s, power 65%, waveform number 15, frequency 85 Hz, duty cycle 100%, on-delay 60 microseconds, off-delay 10 microseconds, corner delay 50 microseconds, and red light speed 500 mm / s.

3. The lithium battery PACK method according to claim 1, characterized in that: Before step one, single cell selection, automatic polarity detection, and automatic pole cleaning are sequentially provided. Single cell selection is used to select cell material bodies that meet processing parameters, automatic polarity detection is used to set the polarity of the cell module, and automatic pole cleaning is used to clean the cell poles for subsequent CCS welding.

4. The lithium battery PACK method according to claim 1, characterized in that: The selection of a single battery cell includes battery cell appearance inspection, battery cell sorting, battery cell stacking, battery cell extrusion, and manual code scanning. Among them, the battery cell appearance inspection is to perform an appearance inspection on the battery cell to check whether the battery cell blue film is damaged, whether there are foreign objects on the blue film, whether the pole is dirty, and whether the explosion-proof valve is damaged. The battery cell sorting is to place the battery cells that have passed the visual inspection during the battery cell appearance inspection on the assembly line tray, and use a sorting machine to automatically sort the single battery cells. Battery stacking and battery cell extrusion are to stack and extrude the single battery cells after the sorting is completed to obtain a battery cell module, and collect the battery cell codes from left to right for the battery cell module. The battery code of the battery cell module generates a module base QR code, and the module base QR code is pasted on the module base.

5. The lithium battery PACK method according to claim 1, characterized in that: The cleaning parameters during 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, and the cleaning power is 80-120w.

6. The lithium battery PACK method according to claim 1, characterized in that: The sorting parameters are voltage: 3.29V-3.3V internal resistance: 0-0.3mΩ.

7. The lithium battery PACK method according to claim 1, characterized in that: In step three, perform a post-weld visual inspection on the battery cell module to ensure that there is no weld offset, black holes, excess height less than 1mm, weld width>3mm, and the gap between the tab and the pole is less than 0.3mm. Use a pry bar to pry the welded tab to ensure that there is no shaking of the tab. The post-weld inspection parameters include weld width, excess height, tab gap, pits, and track diameter. The weld width is 3mm-6mm, the excess height is 0-1mm, the tab gap is 0-0.3mm, the pits are -0.5mm-0mm, and the track diameter is 10mm.

8. The lithium battery PACK method according to claim 1, characterized in that: In step three, the welded battery cell module is automatically tested for total voltage and internal resistance using a voltage internal resistance test device. The total voltage and internal resistance setting parameters include total voltage and internal resistance. The total voltage is 42.77V-42.9V, and the internal resistance is <4mΩ.

9. The lithium battery PACK method according to claim 1, characterized in that: In step four, 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 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 applied in the glue coating areas, and the AB structural glue strips are wave-folded.

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