Bipolar battery

Abstract

The utility model discloses a bipolar battery which comprises a positive monopole plate, a bipolar pole plate, a negative monopole plate and a diaphragm arranged between a positive electrode and a negative electrode, the bipolar pole plate consists of a positive electrode material layer, a conductive substrate and a negative electrode material layer, and the bipolar battery is characterized in that the areas of the positive electrode material layer and the negative electrode material layer are smaller than the area of the conductive substrate; a bonding layer is arranged at the peripheral edge of the conductive substrate, and after the bonding layer is cured and formed, an insulating sealing frame is formed at the edge of each battery unit. According to the utility model, the bonding layer is directly coated on the edge of the conductive substrate and is cured to form the insulating sealing frame, so that the thickness occupation of a traditional sealing frame is avoided, the thickness of the battery unit is obviously reduced, more battery units can be stacked in the same volume, and the energy density and the power density of the battery are improved. According to the utility model, a special adhesive (such as organic silica gel, epoxy resin, polyurethane and the like) is adopted as the adhesive layer, and the adhesive layer has the characteristics of high strength, alkali corrosion resistance and high temperature resistance after being cured, so that the long-term stable operation of the battery in a complex environment is ensured; after the bonding layer is cured, a continuous and uniform insulating sealing frame is formed on the edge of the battery unit, so that electrolyte leakage and external pollutant entering are effectively prevented, and the service life of the battery is prolonged.

Description

TECHNICAL FIELD

[0001] The utility model relates to bipolar battery technical field, concretely relates to a bipolar battery. BACKGROUND

[0002] Bipolar battery is by multiple sealed frame superposition, sealed frame is installed with diaphragm and bipolar pole piece staggered superposition, and the active material of different polarity is coated on the two sides of bipolar pole piece respectively. It can be simply understood as the battery that is composed of multiple battery units in series, and each battery unit is composed of a sealed frame, a bipolar pole piece and a diaphragm. Such a battery has the characteristics of high voltage and high energy density. The voltage of the bipolar battery is related to the number of battery units in series. In order to improve the energy density, it is necessary to reduce the thickness of the battery unit, so as to realize the series superposition of more battery units in a smaller space.

[0003] However, the sealing problem of the current bipolar battery has become the main bottleneck restricting its performance and service life. In the existing bipolar battery, the bipolar plate of each battery unit corresponds to a sealed frame, and a liquid injection hole is provided on the sealed frame for electrolyte injection, and a sealing plug is provided. However, the liquid injection hole occupies a certain thickness space, which limits the thickness of the sealed frame, thereby resulting in insufficient number of battery units that can be superimposed in the bipolar battery of the same volume, ultimately limiting the voltage improvement of the bipolar battery, and failing to fully exert the advantages of high energy density and high power density, which is difficult to meet the urgent demand for high-performance batteries in the fields of electric vehicles, energy storage power stations and other fields. SUMMARY

[0004] The utility model aims at providing a bipolar battery, which aims to solve the problem of limited battery unit thickness, difficult to improve energy density and power density caused by the sealing structure of the existing bipolar battery, and realizes the purpose of high efficiency, low cost and good sealing performance.

[0005] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme:

[0006] The utility model provides a bipolar battery, which comprises a positive single pole plate, a bipolar pole plate, a negative single pole plate, and a diaphragm arranged between the positive and negative electrodes, wherein the bipolar pole plate is composed of a positive electrode material layer, a conductive substrate and a negative electrode material layer, the area of the positive electrode material layer and the negative electrode material layer is smaller than the area of the conductive substrate, and a bonding layer is arranged at the four peripheral edges of the conductive substrate. After curing and forming the bonding layer, an insulating sealed frame is formed at the edge of each battery unit.

[0007] As a further improvement of the above-mentioned scheme, the bonding layer is a semi-solid adhesive, which has high strength, alkali corrosion resistance and high temperature resistance after curing and forming, and can effectively ensure the stable operation of the battery in complex environment.

[0008] As a further improvement of the above scheme, the semi-solid adhesive adopts any one of organic silicone glue, epoxy resin, polyurethane and acrylate, which all have good adhesive property and chemical stability, and can meet the sealing requirement of the bipolar battery.

[0009] As a further improvement of the above scheme, the adhesive layer is double-sided adhesive tape, which has high strength, alkali corrosion resistance and high temperature resistance after curing, so as to ensure the reliability of the sealing.

[0010] As a further improvement of the above scheme, the double-sided adhesive tape adopts a sealing hot melt pressure sensitive adhesive layer.

[0011] As a further improvement of the above scheme, the inner side of the sealing frame is provided with an isolation limiting frame, and the size of the isolation limiting frame is smaller than that of the sealing frame, which has the following effects: 1. isolating and limiting the adhesive layer, preventing the adhesive layer from diffusing into the battery unit during curing; 2. further preventing the positive and negative electrodes from being short-circuited.

[0012] As a further improvement of the above scheme, the isolation limiting frame is made of an elastic material and has a porous structure, so that the electrolyte can be injected into the battery unit.

[0013] As a further improvement of the above scheme, the four peripheral edges of the conductive substrate are not covered by the positive electrode material layer or the negative electrode material layer, so as to provide space for the adhesive layer and ensure that the adhesive layer can effectively play a sealing role.

[0014] Compared with the prior art, the beneficial technical effects of the utility model are as follows:

[0015] The utility model discloses a direct coating adhesive layer on the edge of the conductive substrate and curing to form an insulating sealing frame, avoiding the thickness of the traditional sealing frame, so that the thickness of the battery unit is significantly reduced, more battery units can be stacked in the same volume, and the energy density and power density of the battery are improved.

[0016] The utility model adopts special adhesive (such as organic silicone glue, epoxy resin, polyurethane etc.) as the adhesive layer, which has high strength, alkali corrosion resistance and high temperature resistance after curing, ensuring the long-term stable operation of the battery in complex environment; the adhesive layer forms a continuous and uniform insulating sealing frame on the edge of the battery unit after curing, effectively preventing electrolyte leakage and external pollutants from entering, and prolonging the service life of the battery.

[0017] The utility model adopts integrated sealing design, the adhesive layer is directly coated on the edge of the conductive substrate and cured, without the need of additional installation of the sealing frame, simplifying the production process and reducing the material cost and assembly difficulty. DRAWINGS

[0018] Figure 1Structure diagram (side view) of a bipolar plate.

[0019] Figure 2 Structure diagram (top view) of a bipolar plate.

[0020] Figure 3 Structure diagram of a bipolar battery.

[0021] Figure 4 Perspective view of a battery cell.

[0022] Figure 5 Structure diagram of another battery cell.

[0023] Figure 6 Explanatory view of Figure 5 .

[0024] Figure 7 Structure diagram of a partitioning limiting frame.

[0025] In the figure: 1, conductive substrate; 2, positive electrode material layer; 3, negative electrode material layer; 4, positive monopolar plate; 5, bipolar plate; 6, negative monopolar plate; 7, separator; 8, adhesive layer (sealing frame); 9, partitioning limiting frame; 10, liquid injection hole. DETAILED DESCRIPTION

[0026] In order for those skilled in the art to better understand the technical scheme of the utility model, the utility model will be described in detail below in combination with the drawings, and the description in this part is only exemplary and explanatory, and should not have any limiting effect on the protection scope of the utility model.

[0027] Example 1

[0028] Please refer to Figures 1 to 4 , a bipolar battery, comprising a positive monopolar plate 4, a bipolar plate 5, a negative monopolar plate 6, and a separator 7 arranged between the positive and negative electrodes, the bipolar plate being composed of a positive electrode material layer 2, a conductive substrate 1 and a negative electrode material layer 3, the area of the positive electrode material layer 2 and the negative electrode material layer 3 being smaller than the area of the conductive substrate 1, and an adhesive layer 8 being arranged at the four peripheral edges of the conductive substrate 1, and after the adhesive layer 8 is solidified and formed, an insulating sealing frame 8 is formed at the edge of each battery cell.

[0029] Specifically, in the embodiment, the adhesive layer 8 is a semi-solid adhesive, which has high strength, alkali corrosion resistance and high temperature resistance characteristics after solidification and formation, and can effectively guarantee the stable operation of the battery in a complex environment.

[0030] Specifically, in the embodiment, the semi-solid adhesive is epoxy resin, which has good adhesive performance and chemical stability, and can meet the sealing requirements of the bipolar battery.

[0031] Specifically, in the embodiment, the conductive substrate 1 is a stainless steel plate.

[0032] Embodiment two:

[0033] As a further improvement of the above scheme, the adhesive layer 8 is a double-sided tape, which has high strength, alkali corrosion resistance and high temperature resistance after solidification, to ensure the reliability of the seal.

[0034] Specifically, in the embodiment, the double-sided tape is a sealing hot melt pressure sensitive adhesive layer, which is a prior art and can be obtained through commercial channels.

[0035] Embodiment three:

[0036] As a further improvement of the above scheme, please refer to Figures 5 to 7 , the inner side of the sealing frame 8 is provided with an isolation limiting frame 9, the size of the isolation limiting frame is smaller than the size of the sealing frame, which has the following effects: 1. It is used for isolating and limiting the adhesive layer, preventing the adhesive layer from spreading into the battery cell during the curing process; 2. It further prevents the positive and negative electrodes from being short-circuited.

[0037] Specifically, in the embodiment, the isolation limiting frame is made of an elastic material and has a porous structure, which facilitates the injection of electrolyte into the battery cell. For example, the isolation limiting frame is made of an elastic porous polyethylene material.

[0038] Specifically, in the embodiment, the four edges of the conductive substrate are not covered with positive or negative electrode material layers, which provides space for the setting of the adhesive layer and ensures that the adhesive layer can effectively play a sealing role.

[0039] The sealing method of the above bipolar battery comprises the following steps:

[0040] S1, clean the four edges of the positive monopolar plate, the bipolar plate and the negative monopolar plate to remove oil stains and impurities on the surface;

[0041] S2, uniformly set the adhesive layer on the four edges of the conductive substrate and reserve the liquid injection hole;

[0042] S3, stack the positive monopolar plate, the bipolar plate, the negative monopolar plate and the separator in the order of "positive electrode-separator-negative electrode" and preliminarily fix them by using the adhesive layer to ensure the accuracy and stability of the assembly of the bipolar battery;

[0043] S4, solidify the assembled bipolar battery to form an insulating sealing frame on the edge of each battery cell.

[0044] Specifically, in the embodiment, the adhesive layer is made of organic silicone glue and the solidification method is heating solidification.

[0045] Specifically, in the embodiment, the bonding layer is arranged at the four peripheral edges of the positive and negative surfaces of the bipolar plate, and the bonding layer is arranged at the four peripheral edges of the single surface of the positive and negative single plates.

[0046] Specifically, in the embodiment, the bonding layer is arranged at the four peripheral edges of the single surface of the positive and negative single plates.

[0047] Specifically, in the embodiment, the position and size of the liquid injection hole can be reasonably set according to the design and use requirements of the battery.

[0048] Specifically, in the embodiment, during the curing process, the assembled bipolar battery is subjected to pressure treatment by using a clamp, so as to improve the sealing performance of the battery.

[0049] The utility model discloses a sealing structure and process, realize the thin type of bipolar battery, high energy density and high power density, improve the sealing performance, safety and production efficiency significantly simultaneously.

[0050] It should be noted that in this paper, the term "including", "containing" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, method, article or equipment.

[0051] The principle and implementation mode of the utility model are described by applying specific examples in this paper, and the above examples are only used to help understand the method and core idea of the utility model. The above-mentioned is only the preferred implementation mode of the utility model, and it should be pointed out that due to the limited nature of the expression, there are objectively infinite specific structures, and for ordinary technical personnel in this technical field, on the premise of not departing from the principle of the utility model, some improvements, decorations or changes can be made, and the above technical features can be combined in a proper way, and these improvements, decorations, changes or combinations, or the direct application of the concept and technical scheme of the utility model to other occasions without improvement, should be regarded as the protection scope of the utility model.

Claims

1. A bipolar battery comprising a positive monopolar plate, a bipolar plate, a negative monopolar plate, and a separator provided between the positive and negative plates, the bipolar plate being composed of a positive electrode material layer, an electrically conductive substrate, and a negative electrode material layer, the positive electrode material layer and the negative electrode material layer having an area smaller than that of the electrically conductive substrate, characterized in that, The conductive substrate is provided with a bonding layer at four peripheral edges, and after the bonding layer is cured and formed, an insulating sealing frame is formed at the edge of each battery cell.

2. A bipolar battery according to claim 1, characterized in that The bonding layer is a semi-solid adhesive.

3. A bipolar battery according to claim 1, characterized in that The bonding layer is a double-sided adhesive layer.

4. A bipolar battery according to claim 1, characterized in that An isolation limiting frame is arranged inside the sealing frame, and the size of the isolation limiting frame is smaller than that of the sealing frame.

5. A bipolar battery according to claim 4, characterised in that The isolation limiting frame is made of elastic material and has a porous structure.

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