A manufacturing process for a battery

Abstract

The application discloses a kind of quick preparation process for ETP battery, including the preparation of battery cell, liquid injection, battery cell formation and battery cell packaging, through the coating of positive and negative active material, slice superposition roller pressing battery cell is completed aluminum plastic film packaging and fixture fixing, enter packaging equipment after in turn through import transition bin, packaging bin and outlet transition bin, packaging bin includes injection area, formation area and packaging area, bipolar battery soft pack semi-finished product is removed from import transition bin after being washed, in turn through injection area, formation area and packaging area of packaging bin, complete the bipolar battery that is packaged leaves packaging area, into outlet transition bin, outlet transition cabin is provided with capacity detection equipment, to detect bipolar battery.The application designs a kind of battery process for preparing multiple positive electrode and multiple battery cells, based on the current mainstream liquid injection machine, low dew point environment equipment, formation equipment and fixture, thermoplastic packaging machine and electrical system are redesigned, integrate process flow, improve preparation efficiency and yield.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of batteries, and particularly relates to a manufacturing process of a battery. BACKGROUND

[0002] Lithium ion batteries have the advantage of high energy density, and are therefore widely used in modern life. However, the current lithium ion batteries still cannot meet the demand of users for longer standby time. Therefore, developing battery products with higher energy density has become an urgent requirement of the industry.

[0003] At present, battery packs basically adopt a grouping mode from a single cell to a module to a battery pack, and the multi-level grouping mode is used to ensure the safety of the battery. However, the space utilization rate and energy density of the battery pack are sacrificed. The existing battery internally connects a plurality of energy storage units in series through a current collector to form a battery energy storage system, that is, an ETP (Electrode to pack) battery, which can reduce the packaging weight and volume of the battery, thereby improving the specific energy and specific power of the battery, and has more stable battery performance and lower internal resistance, so that the safety of the battery is greatly improved.

[0004] The current design of the ETP bipolar electrochemical system mainly focuses on a certain energy storage structure, such as an ETP bipolar battery using ternary nickel-cobalt-manganese positive materials (NCM) and an ETP bipolar battery using lithium cobalt oxide (LCO) positive materials. However, each system has disadvantages, and there is no perfect electrochemical system. The ETP bipolar battery using lithium cobalt oxide (LCO) positive materials has high potential, but the cost is high. There is an urgent need for an ETP bipolar electrochemical system with high energy density, environmental adaptability and low cost.

[0005] At the same time, the existing single-polarity battery soft package packaging technology is relatively complex, has a long turnover time, and has a large process control risk, which is difficult to meet the application requirements of the ETP bipolar battery soft package system. In particular, the traditional single-polarity battery soft package production process cannot meet the formation exhaust packaging requirements of the bipolar battery system, and if a secondary sealing process is used, it will bring risks to the ETP highly integrated system. SUMMARY

[0006] To solve the above problems, the application provides a manufacturing process for an ETP battery.

[0007] The technical solutions for achieving the above purposes are as follows:

[0008] A manufacturing process of a battery, the battery comprising at least one first electric core and at least one second electric core, the first electric core comprising a first positive electrode, a first bipolar electrode and a first negative electrode, and the second electric core comprising a second positive electrode, a second bipolar electrode, a second electrolyte and a second negative electrode.

[0009] The first positive electrode comprises a first positive electrode current collector and a first positive electrode active material, and the first positive electrode active material is arranged on the inner side of the first positive electrode current collector; the second positive electrode comprises a second positive electrode current collector and a fourth positive electrode active material, and the fourth positive electrode active material is arranged on the inner side of the second positive electrode current collector;

[0010] The first negative electrode comprises a first negative electrode current collector and a first negative electrode active material, and the first negative electrode active material is arranged on the inner side of the first negative electrode current collector; the second negative electrode comprises a second negative electrode current collector and a second negative electrode active material, and the second negative electrode active material is arranged on the inner side of the second negative electrode current collector;

[0011] The first bipolar electrode comprises a first bipolar electrode current collector, one side of which is provided with a positive electrode active material and the other side is provided with a negative electrode active material, and at least one side of the first bipolar current collector in the first electric core is provided with the second positive electrode active material; the second bipolar electrode comprises a second bipolar electrode current collector, one side of which is provided with the fourth positive electrode active material and the other side is provided with the second negative electrode active material;

[0012] The first positive electrode and the first negative electrode are respectively located at the outermost two sides of the first electric core, the first bipolar electrode is located between the first positive electrode and the first negative electrode, and the active material layers arranged on the opposite sides of the adjacent two electrodes are opposite in polarity; the manufacturing process of the battery comprises the following steps:

[0013] S1: The positive electrode and negative electrode active materials are coated on the corresponding current collectors and formed, and the prepared electrodes are rolled and cut. The first positive electrode and the first negative electrode are respectively arranged at the outermost two sides of the first electric core, the first bipolar electrode is arranged between the first positive electrode and the first negative electrode, the active material layers arranged on the opposite sides of the adjacent two electrodes are opposite in polarity, the second positive electrode and the second negative electrode are respectively arranged at the outermost two sides of the second electric core, the second bipolar electrode is located between the second positive electrode and the second negative electrode, the active material layers arranged on the opposite sides of the adjacent two electrodes are opposite in polarity, the electrodes are arranged in sequence and laminated, the first electric core and the second electric core are separated by a separator, then the bipolar electrodes and the two outermost end electrodes are connected in series to obtain the electric core, the current collector is metalized to leave the tab, and the first electric core and the second electric core are wrapped with an aluminum plastic film to obtain a bipolar battery soft package semi-finished product;

[0014] S2: The bipolar battery soft package semi-finished product enters the import transition warehouse from the first import of the import transition warehouse, the import transition warehouse is filled with protective gas, and the protective gas cleans the bipolar battery soft package semi-finished product;

[0015] S3: The cleaned bipolar battery soft package semi-finished product leaves the first outlet of the import transition cabin and enters the packaging cabin from the import transition cabin, the packaging cabin includes a liquid injection area, a formation area and a packaging area, the bipolar battery soft package semi-finished product sequentially passes through the liquid injection area, the formation area and the packaging area in the packaging cabin to complete the steps of liquid injection, formation and packaging, respectively;

[0016] S4: The bipolar battery that has completed packaging leaves the packaging area and enters the outlet transition cabin, the outlet transition cabin includes a second inlet and a second outlet, the bipolar battery soft package that has completed packaging in the packaging area leaves the packaging area, enters the outlet transition cabin from the second inlet, the outlet transition cabin is provided with a capacity detection device, the capacity detection device detects the bipolar battery soft package, and the bipolar battery soft package that has completed detection leaves the outlet transition cabin through the second outlet to complete preparation.

[0017] Further improvement, preferably the protective gas in the import transition cabin in step S2 is argon, and the cleaning frequency of the bipolar battery soft package semi-finished product by the argon is three times.

[0018] Further improvement, preferably the liquid injection machine is integrated in the liquid injection area in step S3 or is independently connected outside, the liquid injection machine is provided with a liquid injection needle, the liquid injection needle is combined with the liquid injection port of the bipolar battery soft package semi-finished product to perform quantitative liquid injection, the first electrode core is provided with a first liquid injection port, the second electrode core is provided with a second liquid injection port, the liquid injection machine is combined with the liquid injection port of the first electrode core to inject the first electrolyte, and the liquid injection machine is combined with the liquid injection port of the second electrode core to inject the second electrolyte.

[0019] Further improvement, preferably the packaging cabin in step S3 is sealed and connected with a dehumidifier, the dehumidifier continuously dehumidifies the packaging cabin to ensure that the water-oxygen ratio in the packaging cabin is less than or equal to 1 ppm.

[0020] Further improvement, preferably the formation area in step S3 is provided with an electrical interface, the bipolar battery soft package semi-finished product is connected with an external formation system through the electrical interface, and the formation system activates the positive and negative active materials of the bipolar battery soft package semi-finished product.

[0021] Further improvement, preferably the bipolar battery soft package semi-finished product is fixed by a clamp outside before entering the import transition cabin, the two sides and the bottom surface of the bipolar battery soft package semi-finished product are heat-sealed, and the upper end is in an open state.

[0022] Further improvement, preferably the bipolar battery soft package semi-finished product is connected with the formation system outside through the metal tab and the electrical interface.

[0023] Further improvement, preferably the preferred zone is also provided with an exhaust device, in step S3, after the bipolar battery soft package enters the preferred zone, the exhaust device is opened to exhaust the gas generated during the semi-finished product formation of the bipolar battery soft package.

[0024] Further improvement, preferably the preferred zone is also provided with an exhaust device, in step S3, after the bipolar battery soft package enters the preferred zone, the exhaust device is opened to exhaust the gas generated during the semi-finished product formation of the bipolar battery soft package.

[0025] Further improvement, preferably in step S3, after the clamp is pressed, a thermoplastic machine is used to thermoplastic seal the upper end of the bipolar battery soft package semi-finished product, the two sides of the bipolar battery soft package semi-finished product are aluminum films, the clamp is clamped on the two sides of the aluminum film, and the clamp pressing device presses the clamp to thermoplastic seal the upper end of the bipolar battery soft package semi-finished product.

[0026] The present application is aimed at the problems of ETP structure system soft package liquid injection formation and packaging. Compared with traditional single-polarity batteries, bipolar batteries are composed of two positive and negative single-polarity electrodes and a plurality of bipolar electrodes in series, which can realize high-voltage electrochemical systems. ETP structure is based on bipolar batteries, which are directly packaged into module systems by electrode sheets, reducing traditional single-shell, omitting module assembly process, significantly improving energy density, reducing system cost, and bringing lower internal resistance and simplified system advantages.

[0027] The present application is aimed at the problems of ETP structure system soft package liquid injection formation and packaging. Compared with traditional single-polarity batteries, bipolar batteries are composed of two positive and negative single-polarity electrodes and a plurality of bipolar electrodes in series, which can realize high-voltage electrochemical systems. ETP structure is based on bipolar batteries, which are directly packaged into module systems by electrode sheets, reducing traditional single-shell, omitting module assembly process, significantly improving energy density, reducing system cost, and bringing lower internal resistance and simplified system advantages.

[0028] The present application is aimed at the problems of ETP structure system soft package liquid injection formation and packaging. Compared with traditional single-polarity batteries, bipolar batteries are composed of two positive and negative single-polarity electrodes and a plurality of bipolar electrodes in series, which can realize high-voltage electrochemical systems. ETP structure is based on bipolar batteries, which are directly packaged into module systems by electrode sheets, reducing traditional single-shell, omitting module assembly process, significantly improving energy density, reducing system cost, and bringing lower internal resistance and simplified system advantages.

[0029] The application designs a battery manufacturing process, which is based on the redesign and combination of the current mainstream liquid injection machine, low dew point environmental equipment, formation equipment and clamp, heat sealing machine and electrical system, and the process program is compiled, and the ETP bipolar battery soft package is integrated and output. First, based on the special structure of the ETP bipolar battery soft package, each independent positive and negative electrode unit is connected to the formation clamp through the lug, that is, the ETP bipolar battery soft package is first fixed by the formation clamp and the independent positive and negative electrode units are connected. Then enter the inlet transition bin for 3-4 times of protective gas cleaning, and the ETP bipolar battery soft package structure remains open during the process, then quantitative liquid injection is carried out, and the appropriate injection rate and soaking time are selected. After ensuring complete soaking, the formation process is carried out, and obvious gas production phenomenon occurs during the process, and low dew point environment is provided, and the positive pressure gas is discharged and treated in time. After the formation and exhaust are completed, the packaging process is entered, and the soft package aluminum plastic film is heat sealed. The whole process is carried out in a low dew point environment. After the packaging is completed, the outlet transition bin is entered for 3-4 times of protective gas cleaning, and finally the complete soft package ETP bipolar battery soft package product is output.

[0030] The application designs a highly integrated device to solve the problems of liquid injection, formation and packaging in the actual production process of the ETP bipolar battery soft package, and ensures high efficiency and high quality output. The following problems are effectively solved: (1) the difficulty of forming each independent positive and negative electrode unit in the ETP bipolar battery soft package, including the problem of timely exhaust after formation; (2) the traditional process needs secondary sealing, and the application only needs one-time packaging, and the ETP bipolar battery soft package semi-finished product is in an open state in the early stage, which greatly improves the convenience in the actual process; (3) the whole process is carried out in a low dew point environment, which is controlled by an electrical system, and the consistency of the product is ensured, and high quality and high efficiency production is realized. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 It is a first cell structure schematic diagram of the ETP structure-based multi-group electrode battery of the application.

[0032] Figure 2 It is an ETP schematic diagram with multiple component electrodes and multiple cells.

[0033] Figure 3 It is a second cell structure schematic diagram of the ETP structure-based multi-group electrode battery of the application.

[0034] Figure 4 It is a schematic diagram of a bipolar electrode metal cap structure.

[0035] Figure 5 It is a schematic diagram of a traditional battery soft package liquid injection device.

[0036] Figure 6It is a schematic diagram of ETP bipolar battery soft package semi-finished product structure.

[0037] Figure 7 It is a manufacturing equipment of integrated ETP bipolar battery.

[0038] Figure 8 It is a simple step of preparation process of ETP bipolar battery of the application. DETAILED DESCRIPTION

[0039] The application will be further described in detail below with reference to the accompanying drawings.

[0040] In combination Figure 1 A battery based on ETP structure of multiple groups of electrodes, including multiple electrode sheets, assembled into an electric core in a stacked sheet assembly manner of electrode sheets and electrolyte alternately, and the electric core is coated with an outer shell. The inner side surfaces of the outermost two electrode sheets are respectively provided with positive active material layers and negative active material layers, for example, an outer negative piece, an outer positive piece and an electric core series group. The two ends of the electric core series group are respectively provided with a positive end and a negative end. The outer negative piece is connected with the negative end, and the outer positive piece is connected with the positive end. Specifically, the battery includes at least one first electric core 10, the first electric core 10 includes a first positive electrode 19, a first bipolar electrode 18, a first electrolyte 13 and a first negative electrode 17. The first positive electrode 19 includes a first positive electrode current collector 16 and a first positive active material, and the first positive active material is arranged on the inner side of the first positive electrode current collector 16. The first negative electrode 17 includes a first negative electrode current collector 11 and a first negative active material, and the first negative active material is arranged on the inner side of the first negative electrode current collector 11. The first bipolar electrode 18 includes a first bipolar electrode current collector 14, one side of which is provided with a positive active material and the other side is provided with a negative active material. At least one first bipolar current collector 14 in the first electric core has a second positive active material on one side. The first electric core is filled with the first electrolyte 13. The first positive electrode 19 and the first negative electrode 7 are respectively located at the outermost two sides of the first electric core. The first bipolar electrode 14 is located between the first positive electrode 19 and the first negative electrode 17. The active material layers arranged on the opposite surfaces of the adjacent two electrode sheets have opposite polarities.

[0041] The first positive electrode material is a ternary positive electrode material, and the second positive electrode material is lithium iron phosphate (LFP). The ternary positive electrode material is at least one of nickel cobalt manganese acid lithium (NCM) or nickel cobalt aluminum acid lithium (NCA). In the embodiment, the first negative electrode material and the negative electrode material arranged on the surface of the first bipolar electrode current collector 14 are graphite, but the application is not limited to using only graphite as the negative electrode material. In the embodiment, the first electrolyte 13 is a solid-state electrolyte. The use of a solid-state electrolyte can effectively reduce the packaging difficulty of the ETP battery, fundamentally solve the safety hazard caused by liquid leakage, and at the same time, the solid-state electrolyte is also called a fast ion conductor, which has the characteristics of conducting ions and insulating electrons, and has high mechanical strength. The separator assembly can be omitted, and the risk of short circuit caused by negative electrode lithium precipitation is reduced. At the same time, the use of a traditional separator is omitted, the weight of the ETP battery system is reduced, the energy density is improved, and the purpose of simplifying the winding process and reducing the manufacturing cost is achieved.

[0042] Of course, a liquid electrolyte can also be used in other embodiments. When a liquid electrolyte is used, a first separator is arranged at the position of the solid-state electrolyte 13 in Figure 1 The liquid electrolyte is preferably lithium hexafluorophosphate.

[0043] In the embodiment, the first positive electrode current collector 16 is an aluminum foil, the first negative electrode current collector 11 is a copper foil, and the first bipolar current collector 14 is a stainless steel foil. Each foil is provided with a conductive carbon coating. However, the selection of the current collector material is not limited in the application, and all suitable current collector materials are within the scope of the application. For example, the first bipolar current collector 14 can be a conductive polymer composite film. The polymer matrix material of the conductive polymer composite film includes at least one of polyethylene, polypropylene, polystyrene, epoxy resin, and phenolic resin. Further, the conductive filler of the conductive polymer composite film includes at least one of carbon black, carbon nanotubes, graphene, metals, and metal oxides.

[0044] The number of electrodes provided with the first positive electrode material in the first electric core 10 is in a ratio of 1:10 to 15:1 to the number of electrodes provided with the second positive electrode material. The ratio is preferably 1:1.

[0045] In the improved scheme of the first embodiment, the first electric core 10 has at least two first bipolar electrodes 18. The positive electrode active material arranged on one side of the current collector 14 of at least one first bipolar electrode 18 is a third positive electrode active material. The third positive electrode active material is preferably lithium cobalt oxide (LCO) and / or lithium manganese oxide (LMO).

[0046] In order to reduce the volume of the whole battery, the internal cell pole pieces can be tightly attached to the solid electrolyte layer 13, so as to reduce the occupied space of the plurality of internal cell pole pieces, but the present application is not limited to tightly attaching the internal cell pole pieces to the solid electrolyte layer 13, and the positions between the internal cell pole pieces and the solid electrolyte layer 13 can be arranged according to specific use environment, such as frame interval arrangement and the like.

[0047] In combination Figure 2 and 3 , in the second embodiment of the present application, the battery with a plurality of groups of electrodes based on the ETP structure further comprises at least one second cell 20, the second cell being a sodium ion battery system, and specifically, the second cell 20 comprises a second positive electrode 29, a second bipolar electrode 28, a second electrolyte 23 and a second negative electrode 27, the second positive electrode 29 comprises a second positive current collector 26 and a fourth positive active material, the fourth positive active material is arranged on the inner side of the second positive current collector 26, the second negative electrode 27 comprises a second negative current collector 21 and a second negative active material, the second negative active material is arranged on the inner side of the second negative current collector 21, the second bipolar electrode 28 comprises a second bipolar electrode current collector 24, one side of which is provided with the fourth positive active material and the other side is provided with the second negative active material, the second cell 20 is filled with the second electrolyte 23, the second positive electrode 29 and the second negative electrode 27 are respectively located at the outermost two sides of the second cell 20, and the second bipolar electrode 28 is located between the second positive electrode 29 and the second negative electrode 27, the active material layers arranged on the opposite faces of the adjacent two electrodes have opposite polarities.

[0048] The fourth positive active material is at least one of a transition metal oxide, a polyanion compound or a Prussian blue compound, wherein the expression of the transition metal oxide is NaxMO2, 0 Figure 2 As shown in the expression of the transition metal oxide is NaxMO2, 0

[0049] The plurality of groups of cells are connected in series to integrate the advantages of each system battery, such as Figure 2 and 4As shown, the end of the bipolar electrode is metalized, in order to facilitate the connection of each electrode with the lead wire of the power management system, after packaging, a part of each bipolar current collector is exposed at one end of the device, if the conductive polymer film is used as the bipolar current collector, the external end of the bipolar current collector needs to be metalized, the metalization forms a cap-like structure wrapping the end of the current collector, the metalization structure can include single-sided metalization of the current collector, in order to avoid the situation of welding position error in the engineering process, the double-sided metalization is selected, and the end is arranged to form a cap-like structure, so as to ensure effective welding and increase the bonding stability of the metalization; gas phase deposition is used for current collector metalization preparation, the gas phase deposition can form a dense and stable metalization layer to ensure the cycle stability of the battery system, and has excellent thermal and electrical conductivity, which meets the use environment of various types of batteries and ensures the timeliness and effectiveness of battery management, if the bipolar current collector is stainless steel foil, metalization is not needed, only the metal cap-like structure needs to be arranged at the end of the foil.

[0050] As shown in Figure 5 , the current mainstream soft package liquid injection process adopts multiple soft package clamps to enter the liquid injection environment box in groups, electrolyte is introduced through an external pipeline to perform needle tube liquid injection, this liquid injection technology is not suitable for ETP bipolar battery soft package devices, and has problems such as complex technology, long turnover time, and difficulty in water and oxygen control; the bipolar battery preparation process of the above Figures 1-4 is as follows: the battery preparation process of the present application is as follows:

[0051] S1: coat each positive and negative active material on the corresponding current collector and shape, roll and cut the prepared electrode, place the first positive electrode 19 and the first negative electrode 17 on the outermost two sides of the first electric core 10, respectively, place the first bipolar electrode 18 between the first positive electrode 19 and the first negative electrode 17, the polarities of the active material layers arranged on the opposite surfaces of the adjacent two electrodes are opposite, place the second positive electrode 29 and the second negative electrode 27 on the outermost two sides of the second electric core 20, respectively, and place the second bipolar electrode 28 between the second positive electrode 29 and the second negative electrode 27, the polarities of the active material layers arranged on the opposite surfaces of the adjacent two electrodes are opposite, the electrodes are arranged in sequence and laminated, the first electric core and the second electric core are separated by a separator, then the bipolar electrode and the two outermost end electrodes are connected in series to obtain an electric core, the current collector is metalized to leave a tab, the first electric core 10 and the second electric core 20 are wrapped with an aluminum plastic film on the outside to obtain a bipolar battery soft package semi-finished product.

[0052] S2: as shown in Figure 6 , the aluminum plastic film 30 is arranged on the two sides and the bottom surface of the prepared ETP bipolar electric core, and the aluminum plastic film 30 on the two sides and the bottom surface of the ETP bipolar electric core 20 is heat sealed and packaged, and the upper end is in an open state, as shown in Figure 7As shown, after the two sides and the bottom of the thermoplastic packaged ETP bipolar battery soft pack semi-finished product are clamped by the clamp, the two sides and the bottom of the thermoplastic packaged ETP bipolar battery soft pack semi-finished product enter the first inlet of the inlet transition bin 41 from the inlet of the integrated manufacturing equipment, the inlet transition bin 41 is filled with protective gas, the protective gas is used to clean the ETP bipolar battery soft pack semi-finished product, and the cleaning gas is three times, and the gas is argon in this embodiment.

[0053] S3: The cleaned ETP bipolar battery soft pack semi-finished product leaves the inlet transition bin 41 from the first outlet of the inlet transition bin 41 and enters the liquid injection area 42, the liquid injection area 42 is provided with a liquid injection machine or is connected with an external liquid injection machine, the liquid injection needle of the liquid injection machine is aligned with the liquid injection port of the ETP bipolar battery soft pack semi-finished product to combine quantitative liquid injection, so as to ensure that the electrolyte is infiltrated, the first electrode 10 is provided with a first liquid injection port, the second electrode 20 is provided with a second liquid injection port, the liquid injection machine is combined with the liquid injection port of the first electrode 10 to inject the first electrolyte 13, and the liquid injection machine is combined with the liquid injection port of the second electrode to inject the second electrolyte 23.

[0054] After infiltration, the ETP bipolar battery soft pack semi-finished product enters the formation area 43, the formation area 43 provides a constant temperature environment, the formation area 43 is provided with an electrical interface, so that the ETP bipolar battery soft pack semi-finished product in the formation area 43 is electrically connected with an external formation system, the formation system activates the positive and negative active materials of the ETP bipolar battery soft pack semi-finished product, and the ETP bipolar battery soft pack semi-finished product is electrically connected with the external formation system through the metal lead-out tab and the electrical interface. Because gas is generated during the formation process, it is necessary to timely exhaust and ensure a low water-oxygen ratio in a low dew point environment, and the optimal water-oxygen ratio is ≤ 1 ppm, and an exhaust device needs to be arranged in the formation area.

[0055] After the ETP bipolar battery soft pack semi-finished product is formed and exhausted, the ETP bipolar battery soft pack semi-finished product enters the packaging area 44, the packaging area 44 is connected with a vacuum pumping device, the vacuum pumping device pumps the packaging area 44, and the clamp pressurizes the ETP bipolar battery soft pack semi-finished product, and the upper end of the ETP bipolar battery soft pack semi-finished product is closed by thermoplastic.

[0056] S4: The ETP bipolar battery soft pack after sealing enters the outlet transition bin 45 from the second inlet of the outlet transition bin 45, the outlet transition bin 45 is provided with a capacity detection device, the capacity detection device detects the ETP bipolar battery soft pack, and whether the capacity meets the standard, and the ETP bipolar battery soft pack after meeting the standard is output from the second outlet of the outlet transition bin 45. The whole process can be referred to Figure 8As shown, the preparation process meets the injection, formation and sealing requirements of the ETP bipolar battery soft package, realizes highly integrated design, can be continuously produced, and ensures a low dew point environment, wherein the soft package sealing is only one process, reduces the process risk, improves the yield and consistency. As shown in Table 1, from the process engineering point of view, the traditional segmented injection, formation and sealing process is more, and the risk control is difficult. The present application highly integrates different processes, and maintains a low dew point environment throughout, effectively controls failure. The actual yield can be improved by about 10%.

[0057] Table 1: Yield comparison of existing process and ETP integrated process

[0058]

[0059] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A manufacturing process of a battery, characterized by: The battery comprises at least one first cell and at least one second cell, the first cell comprises a first positive electrode, a first bipolar electrode and a first negative electrode, and the second cell comprises a second positive electrode, a second bipolar electrode, a second electrolyte and a second negative electrode; The first positive electrode comprises a first positive electrode current collector and a first positive electrode active material, and the first positive electrode active material is arranged on the inner side of the first positive electrode current collector; the second positive electrode comprises a second positive electrode current collector and a fourth positive electrode active material, and the fourth positive electrode active material is arranged on the inner side of the second positive electrode current collector; the first positive electrode active material is a ternary positive electrode material, and the second positive electrode active material is lithium iron phosphate; the ternary positive electrode material is at least one of lithium nickel cobalt manganese oxide or lithium nickel cobalt aluminum oxide; and the fourth positive electrode active material is at least one of a transition metal oxide, a polyanion compound or a Prussian blue compound; The first negative electrode comprises a first negative electrode current collector and a first negative electrode active material, and the first negative electrode active material is arranged on the inner side of the first negative electrode current collector; the second negative electrode comprises a second negative electrode current collector and a second negative electrode active material, and the second negative electrode active material is arranged on the inner side of the second negative electrode current collector; The first bipolar electrode comprises a first bipolar electrode current collector, one side of which is provided with a positive electrode active material and the other side is provided with a negative electrode active material, and at least one first bipolar current collector in the first cell is provided with the second positive electrode active material on one side; the second bipolar electrode comprises a second bipolar electrode current collector, one side of which is provided with the fourth positive electrode active material and the other side is provided with the second negative electrode active material; The first positive electrode and the first negative electrode are respectively located at the outermost two sides of the first cell, the first bipolar electrode is located between the first positive electrode and the first negative electrode, and the active material layers arranged on the opposite sides of the adjacent two electrodes are opposite in polarity; the manufacturing process of the battery comprises the following steps: S1: The positive electrode and negative electrode active materials are coated on the corresponding current collectors and formed, and the prepared electrodes are rolled and cut; the first positive electrode and the first negative electrode are respectively arranged at the outermost two sides of the first cell, the first bipolar electrode is arranged between the first positive electrode and the first negative electrode, the active material layers arranged on the opposite sides of the adjacent two electrodes are opposite in polarity, the second positive electrode and the second negative electrode are respectively arranged at the outermost two sides of the second cell, the second bipolar electrode is located between the second positive electrode and the second negative electrode, the active material layers arranged on the opposite sides of the adjacent two electrodes are opposite in polarity, the electrodes are sequentially arranged and laminated, the first cell and the second cell are separated by a separator, then the bipolar electrode and the two outermost end electrodes are connected in series to obtain a cell, the current collector is metalized to leave a tab, and the first cell and the second cell are wrapped with an aluminum plastic film to obtain a bipolar battery soft pack semi-finished product. S2: the bipolar battery soft package semi-product enters the import transition warehouse from the first import of the import transition warehouse, the import transition warehouse is filled with protective gas, and the protective gas cleans the bipolar battery soft package semi-product; S3: the cleaned bipolar battery soft package semi-product leaves the import transition warehouse from the first outlet of the import transition warehouse and enters the packaging warehouse, the packaging warehouse includes a liquid injection area, a formation area and a packaging area, the bipolar battery soft package semi-product sequentially passes through the liquid injection area, the formation area and the packaging area in the packaging warehouse to complete the steps of liquid injection, formation and packaging respectively, the bipolar battery soft package semi-product is fixed by a clamp before entering the import transition warehouse, the two sides and the bottom surface of the bipolar battery soft package semi-product are thermally sealed, and the upper end is in an open state, the bipolar battery soft package semi-product sequentially completes liquid injection and formation, exhausts after formation is completed, and then enters the packaging area to heat seal the open upper end of the bipolar battery soft package semi-product; S4: the bipolar battery soft package that completes packaging leaves the packaging area and enters the outlet transition warehouse, the outlet transition warehouse includes a second import and a second outlet, the bipolar battery soft package that completes packaging in the packaging area leaves the packaging area, enters the outlet transition warehouse from the second import, the outlet transition cabin is provided with a capacity detection device, the capacity detection device detects the bipolar battery soft package, the bipolar battery soft package that completes detection leaves the outlet transition warehouse through the second outlet, and the preparation is completed.

2. The manufacturing process of a battery according to claim 1, wherein, The protective gas in the import transition warehouse in the step S2 is argon, and the cleaning frequency of the bipolar battery soft package semi-product by the argon is three times.

3. The manufacturing process of a battery according to claim 1, wherein, The liquid injection area in the step S3 is integrally provided with a liquid injection machine or is externally connected with an independent liquid injection machine, the liquid injection machine is provided with a liquid injection needle, the liquid injection needle is combined with the liquid injection port of the bipolar battery soft package semi-product to perform quantitative liquid injection, the first electric core is provided with a first liquid injection port, the second electric core is provided with a second liquid injection port, the liquid injection machine is combined with the liquid injection port of the first electric core to inject the first electrolyte, and the liquid injection machine is combined with the liquid injection port of the second electric core to inject the second electrolyte.

4. The manufacturing process of a battery according to claim 3, wherein The packaging warehouse in the step S3 is sealed and connected with a dehumidifier, the dehumidifier continuously dehumidifies the packaging warehouse to ensure that the packaging warehouse is in a low water-oxygen ratio state, and the water-oxygen ratio is less than or equal to 1 ppm.

5. The manufacturing process of a battery according to claim 4, wherein, The formation area in the step S3 is provided with an electrical interface, the bipolar battery soft package semi-product is connected with an external formation system through the electrical interface, and the formation system activates the positive and negative active materials of the bipolar battery soft package semi-product.

6. The manufacturing process of a battery according to claim 5, wherein, The bipolar battery soft package semi-product is connected with the external formation system through the electrical interface through a metal lead-out tab.

7. The manufacturing process of a battery according to claim 5, wherein, The formation area is also provided with an exhaust device, and in the step S3, the bipolar battery soft package semi-product enters the formation area, the exhaust device is started to exhaust the gas generated when the bipolar battery soft package semi-product is formed.

8. The manufacturing process of a battery according to claim 5, wherein, The packaging area is provided with a vacuumizing device and a clamp pressurizing device, after the bipolar battery soft pack semi-product after formation in step S4 enters the packaging area, the vacuumizing device is started to vacuumize the packaging area, and the clamp pressurizing device is used to press the clamp.

9. The manufacturing process of a battery according to claim 8, wherein, After the clamp is pressed in step S3, a thermoplastic machine is used to thermoplastic seal the upper end of the bipolar battery soft pack semi-product, the two sides of the bipolar battery soft pack semi-product are aluminum films, the clamp is clamped on the two aluminum films, and the clamp pressurizing device is used to press the clamp to thermoplastic seal the upper end of the bipolar battery soft pack semi-product.

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