Battery, preparation method, battery module and power utilization device

Abstract

The invention belongs to the technical field of lithium battery production, and relates to a battery and a preparation method thereof, a battery module and a power utilization device, the battery comprises a battery top cover, at least two battery cells, at least one positive pole, at least one negative pole, at least one positive pole connecting sheet and at least one negative pole connecting sheet. According to the invention, the positive and negative poles and the positive and negative connecting sheets are designed in different regions, and the insulating material is filled between the regions, so that double isolation of physical and circuit is realized, no current cross exists between the two battery cells, and two independent short-circuit loops are formed, therefore, energy is only released by a single battery cell, the total thermal runaway energy is obviously reduced, the overall detonation is avoided, and the service life of the battery is prolonged. And the probability of passing the acupuncture test is obviously improved.

Description

Technical Field

[0001] This invention relates to the field of lithium battery production technology, and in particular to a battery and its preparation method, a battery module, and an electrical device. Background Technology

[0002] With the rapid development of the new energy vehicle industry, more stringent dual requirements have been placed on the energy density and safety of power lithium batteries. Among the many battery structures, square aluminum-cased batteries have become the mainstream choice in the field of power batteries due to their high assembly efficiency and good structural strength.

[0003] To meet high-capacity requirements, existing square aluminum-cased batteries generally employ a multi-cell parallel structure. The positive and negative electrodes of each cell are connected to their corresponding integrated positive and negative terminals via integrally molded positive and negative electrode connectors. While this parallel structure is relatively simple to manufacture, it presents a fatal safety hazard: it establishes a shared, low-impedance current path for the two cells in the circuit topology. When the battery encounters extreme abuse conditions, such as a nail penetration test, the metal needle can simultaneously pierce the casing and separator of both cells, causing a short circuit within both cells. At this point, a huge short-circuit current flows rapidly between the two cells through the shared current path, creating a "cumulative effect" of current and heat. This means that the total energy of thermal runaway is a direct sum of the energy of the two cells; furthermore, thermal runaway in one cell can rapidly trigger a chain reaction in the other cell through the conductive connectors, leading to violent decomposition and gas expansion of the electrolyte, ultimately causing a complete battery explosion. Summary of the Invention

[0004] To address the aforementioned problems, this invention discloses a battery and its preparation method, a battery module, and an electrical device. The technical solution of this invention is implemented as follows:

[0005] The first aspect of the present invention discloses a battery, including a battery top cover, at least two battery cells, and an electrode assembly and a connecting piece assembly disposed on the battery top cover;

[0006] The pole assembly includes:

[0007] The positive terminal post is divided into a first section and a second section of the positive terminal post, which are insulated from each other by a first insulating material.

[0008] The negative terminal is divided into a first negative terminal section and a second negative terminal section, which are insulated from each other by a second insulating material.

[0009] The connecting piece assembly includes:

[0010] The positive electrode connecting piece is divided into a first section and a second section of the positive electrode connecting piece, which are insulated from each other by a third insulating material;

[0011] The negative electrode connecting piece is divided into a first section and a second section of the negative electrode connecting piece, which are insulated from each other by a fourth insulating material;

[0012] At least two battery cells include:

[0013] The first cell is connected to the first section of the positive terminal via the first section of the positive terminal connector, and to the first section of the negative terminal connector via the first section of the negative terminal connector.

[0014] The second cell is connected to the second section of the positive terminal via the second section of the positive terminal connector, and to the second section of the negative terminal connector via the second section of the negative terminal connector.

[0015] The first and second cells form two parallel and independent circuits inside the battery.

[0016] Specifically, the distance between the first and second positive electrode sections is 0.5mm to 5mm; the distance between the first and second negative electrode sections is 0.5mm to 5mm.

[0017] Specifically, the first insulating material, the second insulating material, the third insulating material, and the fourth insulating material are independently selected from at least one of polyimide, polytetrafluoroethylene, polyetheretherketone, silicone rubber, fluororubber, epoxy resin, or alumina ceramic.

[0018] A second aspect of the present invention discloses a method for preparing a battery, the method being used to prepare the battery disclosed in the first aspect of the present invention, the method comprising the following steps:

[0019] S1. Provide a positive terminal and a negative terminal, and divide the positive terminal into a first positive terminal section and a second positive terminal section by a first insulating space; divide the negative terminal into a first negative terminal section and a second negative terminal section by a second insulating space; assemble the formed positive terminal and negative terminal to the corresponding mounting positions on the battery top cover;

[0020] S2. Fill the first insulating space with the first insulating material, fix it with high-temperature adhesive, and cure it under a protective atmosphere; fill the second insulating space with the second insulating material, fix it with high-temperature adhesive, and cure it under a protective atmosphere.

[0021] S3. Process the positive electrode connecting piece into a first positive electrode connecting piece and a second positive electrode connecting piece; process the negative electrode connecting piece into a first negative electrode connecting piece and a second negative electrode connecting piece; isolate the first positive electrode connecting piece and the second positive electrode connecting piece with a third insulating material; isolate the first negative electrode connecting piece and the second negative electrode connecting piece with a fourth insulating material; then weld the positive electrode connecting piece to the corresponding positive electrode post, and weld the negative electrode connecting piece to the corresponding negative electrode post;

[0022] S4. Solder the tab of one of the two battery cells to the first section of the positive electrode connection piece and the first section of the negative electrode connection piece, and solder the tab of the other battery cell to the second section of the positive electrode connection piece and the second section of the negative electrode connection piece.

[0023] S5, casing, encapsulation, drying, and electrolyte injection form a battery with a dual-cell parallel structure.

[0024] Specifically, high-temperature adhesives include at least one of silicone adhesives, epoxy adhesives, special polymer adhesives, or inorganic adhesives.

[0025] Specifically, in step S2, the high-temperature adhesive is applied using one of the following methods: automatic dispensing machine application, ultrasonic / electrostatic spraying, micro-contact printing, aerosol jet printing, or laser-assisted deposition.

[0026] Specifically, in step S2, the gap between the first insulating material and the positive electrode post is ≤0.1mm; the gap between the second insulating material and the negative electrode post is ≤0.1mm.

[0027] Specifically, in step S4, the physical separation distance between the welding positions of the positive or negative tabs of the two cells is ≥5mm.

[0028] A third aspect of the present invention discloses a battery module, the battery module comprising the battery disclosed in the first aspect of the present invention.

[0029] The fourth aspect of the present invention discloses an electrical device, which includes the battery module disclosed in the third aspect of the present invention.

[0030] Beneficial technical effects of the present invention:

[0031] This invention achieves dual physical and electrical isolation of parallel battery cells by designing the terminals and connecting plates in separate sections and filling the spaces between them with insulating material. This structural innovation fundamentally changes the current path and energy release pattern of the battery during a short-circuit fault. Specifically, in the nail penetration test, when a steel needle penetrates two cells simultaneously, the short-circuit current generated by each cell is strictly limited to its own independent circuit due to the obstruction of the intermediate insulating material; that is, the short-circuited current flows from the short-circuited cell to its corresponding connecting plate section and then to its corresponding terminal section. There is no current crossing or energy transfer between the two cells. Therefore, this invention transforms the energy of thermal runaway from the superimposed release of two cells in the traditional structure into the independent release of a single cell, thereby significantly reducing the total thermal runaway energy and peak temperature, effectively avoiding overall deflagration, and greatly improving the reliability and safety of the battery in the nail penetration test. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention;

[0034] Figure 2 This is a top view of an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of the back structure of the battery top cover in an embodiment of the present invention.

[0036] The symbols in the above figures have the following meanings:

[0037] 1. Positive terminal; 2. Negative terminal; 3. Injection hole; 4. Explosion-proof valve; 5. First insulating material; 6. Second insulating material; 7. Connecting piece (including positive / negative connecting piece); 8. Lower plastic; 9. Third insulating material; 10. Fourth insulating material; 11. Battery top cover; 12. Battery cell; 13. Battery casing; 14. Tab. Detailed Implementation

[0038] In a conventional prismatic battery, the terminals of two cells are directly connected in parallel via a single connecting piece. During a needle puncture, the metal needle will pierce both cells simultaneously, causing a short circuit within each cell and resulting in a buildup of heat. The electrolyte will react violently, releasing energy in a concentrated manner, which can easily trigger thermal runaway.

[0039] To address the above problems, this invention proposes a technical solution.

[0040] The first aspect of the present invention discloses a battery, the battery comprising a battery top cover, at least two battery cells, and an electrode assembly and a connecting piece assembly disposed on the battery top cover;

[0041] The pole assembly includes:

[0042] The positive terminal post is divided into a first section and a second section of the positive terminal post, which are insulated from each other by a first insulating material.

[0043] The negative terminal is divided into a first negative terminal section and a second negative terminal section, which are insulated from each other by a second insulating material.

[0044] The connecting piece assembly includes:

[0045] The positive electrode connecting piece is divided into a first section and a second section of the positive electrode connecting piece, which are insulated from each other by a third insulating material;

[0046] The negative electrode connecting piece is divided into a first section and a second section of the negative electrode connecting piece, which are insulated from each other by a fourth insulating material;

[0047] At least two battery cells include:

[0048] The first cell is connected to the first section of the positive terminal via the first section of the positive terminal connector, and to the first section of the negative terminal connector via the first section of the negative terminal connector.

[0049] The second cell is connected to the second section of the positive terminal via the second section of the positive terminal connector, and to the second section of the negative terminal connector via the second section of the negative terminal connector.

[0050] The first and second cells form two parallel and independent circuits inside the battery.

[0051] This invention achieves dual physical and electrical isolation of parallel battery cells by designing the terminals and connecting plates in separate sections and filling the spaces between them with insulating material. This structural innovation fundamentally changes the current path and energy release pattern of the battery during a short-circuit fault. Specifically, in the nail penetration test, when a steel needle penetrates two cells simultaneously, the short-circuit current generated by each cell is strictly limited to its own independent circuit due to the obstruction of the intermediate insulating material; that is, the short-circuited current flows from the short-circuited cell to its corresponding connecting plate section and then to its corresponding terminal section. There is no current crossing or energy transfer between the two cells. Therefore, this invention transforms the energy of thermal runaway from the superimposed release of two cells in the traditional structure into the independent release of a single cell, thereby significantly reducing the total thermal runaway energy and peak temperature, effectively avoiding overall deflagration, and greatly improving the reliability and safety of the battery in the nail penetration test.

[0052] It should be noted that the core concept of this invention lies in achieving circuit isolation of parallel cells through the insulating separation between the terminals and the connecting pieces. Those skilled in the art, after understanding the above concept, will readily recognize its applicability to battery systems containing more than two cells, and all variations based on the same inventive concept should fall within the protection scope of this invention.

[0053] In some implementations, the distance between the first positive terminal block and the second positive terminal block is 0.5 mm to 5 mm; the distance between the first negative terminal block and the second negative terminal block is 0.5 mm to 5 mm.

[0054] If the spacing between the positive and negative terminals is too small, the thickness of the insulating material will be insufficient, potentially reducing its electrical insulation and mechanical support strength. This makes it difficult for the battery to reliably withstand system voltage and mechanical stress throughout its lifespan, posing a risk of insulation failure. Conversely, if the spacing is too large, it will unnecessarily increase the amount of high-reliability insulating material used, leading to higher costs. Furthermore, it will excessively occupy the limited space of the battery top cover, hindering improvements in battery energy density and compact structural design. Therefore, controlling the spacing between the positive and negative terminals within the range of 0.5mm to 5mm achieves the optimal balance between cost and space efficiency while ensuring reliable electrical isolation.

[0055] In practical applications, the distance between the first and second positive electrode sections can be selected as 0.5mm, 0.8mm, 0.9mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, 4mm, 4.2mm, 4.5mm, 4.8mm, 5mm, etc.; the distance between the first and second negative electrode sections can be selected as 0.5mm, 0.8mm, 0.9mm, 1mm, 1.2mm, 1.5mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, 4mm, 4.2mm, 4.5mm, 4.8mm, 5mm, etc.

[0056] It should be noted that the values ​​listed above are examples and not limitations. Those skilled in the art can set the spacing according to their needs. The above distances are only required for filling the insulating material, as long as the pole sections are isolated from each other.

[0057] In some embodiments, the first insulating material, the second insulating material, the third insulating material, and the fourth insulating material are independently selected from at least one of polyimide, polytetrafluoroethylene, polyetheretherketone, silicone rubber, fluororubber, epoxy resin, or alumina ceramic.

[0058] The term "at least one" in this invention refers to selecting one element from all the listed elements, or selecting a mixture of two or more elements from the listed elements as the technical solution. Since the aforementioned insulating materials do not chemically react with each other and do not affect their respective physicochemical properties, those skilled in the art can freely implement this solution. Furthermore, although the selection ranges for the first, second, third, and fourth insulating materials are the same, they can be the same or different in specific implementations.

[0059] In some implementations, the positive electrode post is made of one of the following materials: aluminum, aluminum alloy, stainless steel, titanium, titanium alloy, or nickel-plated steel.

[0060] The negative electrode post can be made of one of the following materials: copper, copper alloy, nickel-plated steel, pure iron, or stainless steel.

[0061] Both the positive and negative terminals are made of conventional materials.

[0062] A second aspect of the present invention discloses a method for preparing a battery, for preparing the battery disclosed in the first aspect of the present invention, comprising the following steps:

[0063] S1. Provide a positive terminal and a negative terminal, and divide the positive terminal into a first positive terminal section and a second positive terminal section by a first insulating space; divide the negative terminal into a first negative terminal section and a second negative terminal section by a second insulating space; assemble the formed positive terminal and negative terminal to the corresponding mounting positions on the battery top cover;

[0064] In some implementations, the partitioning method in step S1 can be achieved by stamping, for example, stamping a single piece of positive or negative electrode material into a partitioned structure. Alternatively, two positive electrode materials can be used as the first and second partitions, respectively, and the same applies to the negative electrode. Furthermore, the partitioning structure of the positive electrode can be semi-circular, rectangular, square, etc.

[0065] S2. Fill the first insulating space with the first insulating material, fix it with high-temperature adhesive, and cure it under a protective atmosphere; fill the second insulating space with the second insulating material, fix it with high-temperature adhesive, and cure it under a protective atmosphere.

[0066] S3. Process the positive electrode connecting piece into a first positive electrode connecting piece and a second positive electrode connecting piece; process the negative electrode connecting piece into a first negative electrode connecting piece and a second negative electrode connecting piece; the first positive electrode connecting piece and the second positive electrode connecting piece are isolated by a third insulating material; the first negative electrode connecting piece and the second negative electrode connecting piece are isolated by a fourth insulating material; then weld the positive electrode connecting piece to the corresponding positive electrode post, and weld the negative electrode connecting piece to the corresponding negative electrode post; the processing method of the positive electrode connecting piece and the negative electrode connecting piece is similar to the processing method of the positive electrode post and the negative electrode post, and will not be described in detail in this invention.

[0067] During welding, the first section of the positive electrode connecting piece is welded to the first section of the positive electrode post, the first section of the negative electrode connecting piece is welded to the first section of the negative electrode post, the second section of the positive electrode connecting piece is welded to the second section of the positive electrode post, and the second section of the negative electrode connecting piece is welded to the second section of the negative electrode post. Laser welding is used to ensure low internal resistance. To avoid breakdown of the insulation material, the welding power is controlled within the range of ≤3000W for the positive electrode and ≤5400W for the negative electrode.

[0068] S4. Solder the tab of one of the two battery cells to the first section of the positive electrode connection piece and the first section of the negative electrode connection piece, and solder the tab of the other battery cell to the second section of the positive electrode connection piece and the second section of the negative electrode connection piece, forming a dual-cell parallel but circuit-isolated architecture.

[0069] S5, casing, encapsulation, drying, and electrolyte injection form a battery with a dual-cell parallel structure.

[0070] In specific applications, high-temperature adhesives include at least one of silicone adhesives, epoxy adhesives, special polymer adhesives, or inorganic adhesives.

[0071] In specific applications, in step S2, the high-temperature adhesive is applied using one of the following methods: automatic dispensing machine application, ultrasonic / electrostatic spraying, micro-contact printing, aerosol jet printing, or laser-assisted deposition.

[0072] In specific applications, in step S2, the gap between the first insulating material and the positive electrode post is ≤0.1mm; the gap between the second insulating material and the negative electrode post is ≤0.1mm.

[0073] In some implementations, in step S4, the physical separation distance between the welding positions of the positive or negative tabs of the two cells is ≥5mm. This is done to prevent pin piercing from causing solder joint bridging.

[0074] A third aspect of the present invention discloses a battery module, the battery module comprising the battery disclosed in the first aspect of the present invention.

[0075] The fourth aspect of the present invention discloses an electrical device, which includes the battery module disclosed in the third aspect of the present invention.

[0076] The embodiments of the present invention will be described in more detail below through examples and comparative examples. It should be noted that the embodiments of the present invention are not limited to these examples.

[0077] Furthermore, to reduce errors, all batteries in the embodiments and comparative examples of this invention are prepared using the same process and with identical materials. Specifically:

[0078] Example: A square lithium-ion battery, such as Figures 1-3 As shown, the preparation method is as follows:

[0079] 1. Preparation of the positive and negative terminals:

[0080] The positive electrode post 1 is made of 1050 aluminum alloy, and is round with a diameter of 2cm.

[0081] The negative terminal 2 is made of C1100 pure copper, and is round with a diameter of 2cm.

[0082] The positive and negative electrode materials are precision stamped into symmetrical semi-circular partitioned structures (radius 1cm). A 2mm insulating space is reserved in the middle of the partitioned structure of the positive electrode 1 to fill the first insulating material 5. In this embodiment, the first insulating material 5 is a 3mm thick alumina ceramic sheet (Al2O3 content ≥99%). The alumina ceramic sheet is laser-cut into 2mm wide insulating strips. A two-component silicone high-temperature adhesive (adhesive line width 0.3mm) resistant to 500℃ is applied into the aluminum alloy electrode groove using an automatic dispensing machine. Precision fixtures are used for positioning, ensuring the gap between the ceramic sheet and the electrode is ≤0.05mm. The mixture is cured at 180℃ for 2 hours under nitrogen protection.

[0083] The negative electrode post 2 has a 2mm insulating space reserved in the middle of the partition structure for filling the second insulating material 6. In this embodiment, the second insulating material 6 is a 3mm thick alumina ceramic sheet (Al2O3 content ≥99%). The alumina ceramic sheet is laser-cut into 2mm wide isolation strips. A two-component silicone high-temperature adhesive (adhesive line width 0.3mm) that can withstand 500℃ is applied to the aluminum alloy electrode post groove using an automatic dispensing machine. Precision fixtures are used for positioning so that the gap between the ceramic sheet and the electrode post is ≤0.05mm. It is cured at 180℃ for 2 hours under nitrogen protection.

[0084] 2. Preparation of the connecting piece 7 for the positive and negative electrodes:

[0085] The positive electrode connector is made of 3003 aluminum alloy.

[0086] The negative electrode connector is made of T2 copper.

[0087] The connecting material of the positive and negative electrodes is precision stamped into a symmetrical partitioned structure.

[0088] The positive electrode connector has a partitioned structure with a 0.5mm thick polyimide film filling the middle as a third insulating material.

[0089] The negative electrode connecting piece has a partitioned structure with a 0.5mm thick polyimide film filling the middle as a fourth insulating material 10.

[0090] 3. Manufacturing process of poles and connecting pieces:

[0091] The positive electrode connector is laser-welded to the positive electrode post 1 onto the battery top cover 11 with a welding power of 2500W. The negative electrode connector is laser-welded to the negative electrode post 2 onto the battery top cover 11 with a welding power of 5100W. The battery top cover 11 is also equipped with an explosion-proof valve 4, a lower plastic insert 8, and a liquid injection hole 3.

[0092] 4. Cell 12 connection: Two 50Ah NCM811 wound cells are used, with a total capacity of 100Ah.

[0093] The tab 14 of the positive electrode (made of aluminum) is welded to the connecting piece of the positive electrode by YAG laser, and the tab 14 of the negative electrode (made of copper) is welded to the connecting piece of the negative electrode by fiber laser; the distance between the welding positions of the positive tabs of the two battery cells is 6.0 mm, and the distance between the welding positions of the negative tabs of the two battery cells is 7.5 mm (both > 5 mm safety distance).

[0094] After welding the battery top cover 11 to the battery cell 12, electrolyte is injected into the battery case 13 through the liquid injection hole 3 on the battery top cover 11. The electrolyte is a mixed solvent of 1M LiPF6 dissolved in a volume ratio of 1:1:1 of EC:EMC:DMC.

[0095] Pinprick test:

[0096] Take 30 battery samples. Charge all the batteries fully, and then use a high-temperature resistant steel needle with a diameter of 5 mm to penetrate from the direction perpendicular to the battery plate at a speed of 25 mm / s. The penetration position should be close to the geometric center of the pierced surface, and the steel needle stays in the battery. After observing for 1 hour, if the battery does not catch fire or explode, it is considered qualified.

[0097] The passing rate of the pinprick test is 100%.

[0098] Comparative example:

[0099] The battery structure of the comparative example is basically the same as that of the embodiment, except that in the comparative example, the positive electrode column, negative electrode column, positive electrode connecting piece, and negative electrode connecting piece do not have a partition structure.

[0100] Pinprick test:

[0101] Take 30 battery samples. Charge all the batteries fully, and then use a high-temperature resistant steel needle with a diameter of 5 mm to penetrate from the direction perpendicular to the battery plate at a speed of 25 mm / s. The penetration position should be close to the geometric center of the pierced surface, and the steel needle stays in the battery. After observing for 1 hour, if the battery does not catch fire or explode, it is considered qualified.

[0102] The passing rate of the pinprick test is 49%.

[0103] Comparing the embodiment and the comparative example, it can be seen that when the steel needle penetrates from one long side of the square shell battery prepared by the present invention, it penetrates through two battery cells. The short-circuit current of each battery cell only flows through its corresponding electrode column partition (due to the阻隔 of the intermediate insulating material), and there is no current cross between the two battery cells, forming two independent short-circuit loops. Therefore, the energy is only released by a single battery cell, significantly reducing the total thermal runaway energy, avoiding overall deflagration, and making it easier to pass the pinprick test.

[0104] It should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A battery, characterized by, The battery top cover, at least two battery cells, and a pole assembly and a connecting plate assembly arranged on the battery top cover; The pole assembly comprises: a positive pole, which is separated by a first insulating material into a positive pole first subarea and a positive pole second subarea that are insulated from each other; a negative pole, which is separated by a second insulating material into a negative pole first subarea and a negative pole second subarea that are insulated from each other; The connecting plate assembly comprises: a positive connecting plate, which is separated by a third insulating material into a positive connecting plate first subarea and a positive connecting plate second subarea that are insulated from each other; a negative connecting plate, which is separated by a fourth insulating material into a negative connecting plate first subarea and a negative connecting plate second subarea that are insulated from each other; The at least two battery cells comprise: a first battery cell, which is connected to the positive pole first subarea through the positive connecting plate first subarea and to the negative pole first subarea through the negative connecting plate first subarea; a second battery cell, which is connected to the positive pole second subarea through the positive connecting plate second subarea and to the negative pole second subarea through the negative connecting plate second subarea; The first battery cell and the second battery cell form two parallel and circuit-independent loops inside the battery.

2. The battery of claim 1, wherein, The distance between the positive pole first subarea and the positive pole second subarea is 0.5-5 mm, and the distance between the negative pole first subarea and the negative pole second subarea is 0.5-5 mm.

3. The battery of claim 1, wherein, The first, second, third, and fourth insulating materials are independently selected from at least one of polyimide, polytetrafluoroethylene, polyether ether ketone, silicone rubber, fluororubber, epoxy resin, and alumina ceramic.

4. A method of producing a battery, characterized by The method comprises the following steps: S1. Providing a positive pole and a negative pole, separating the positive pole into a positive pole first subarea and a positive pole second subarea through a first insulating space, separating the negative pole into a negative pole first subarea and a negative pole second subarea through a second insulating space, and assembling the shaped positive pole and negative pole to corresponding mounting positions of a battery top cover; S2. Filling the first insulating space with a first insulating material, fixing with high-temperature glue, and curing in a protective atmosphere; filling the second insulating space with a second insulating material, fixing with high-temperature glue, and curing in a protective atmosphere; S3. Processing a positive connecting plate into a positive connecting plate first subarea and a positive connecting plate second subarea, processing a negative connecting plate into a negative connecting plate first subarea and a negative connecting plate second subarea, isolating the positive connecting plate first subarea and the positive connecting plate second subarea with a third insulating material, isolating the negative connecting plate first subarea and the negative connecting plate second subarea with a fourth insulating material, and then correspondingly welding the positive connecting plate to the positive pole and the negative connecting plate to the negative pole; S4. Welding the tab of one of the two battery cells to the positive connecting plate first subarea and the negative connecting plate first subarea and the tab of the other battery cell to the positive connecting plate second subarea and the negative connecting plate second subarea; S5. Encasing, packaging, drying, and injecting liquid to form a battery with a double-battery-cell parallel structure.

5. The method of claim 4, wherein, The high-temperature adhesive comprises at least one of silicone-based adhesive, epoxy-based adhesive, special polymer-based adhesive or inorganic-based adhesive.

6. The method of claim 4, wherein, In step S2, the coating of the high-temperature adhesive is performed by one of automatic dispensing machine coating, ultrasonic / electrostatic spraying, micro-contact printing, aerosol jet printing or laser-assisted deposition.

7. The method of claim 4, wherein, In step S2, the gap between the first insulating material and the positive pole column is ≤0.1 mm; and the gap between the second insulating material and the negative pole column is ≤0.1 mm.

8. The method of claim 4, wherein, In step S4, the physical separation distance between the welding positions of the positive or negative tabs of the two battery cells is ≥5 mm.

9. A battery module, characterized by The battery comprises the battery as claimed in any one of claims 1-3, or is prepared by the preparation method as claimed in any one of claims 4-8.

10. An electrical device, characterized by The battery module comprises the battery as claimed in claim 9.

Images