Novel battery module and battery pack thereof

Abstract

The utility model discloses a novel battery module and a battery pack, and relates to a novel battery module consisting of soft package battery cells. When a soft package battery cell works, a tab part of the battery cell is easy to be unglued due to temperature, so that the interior of the battery cell is communicated with the outside, and humid air enters the battery cell, so that the battery cell fails in advance. The battery module has the main advantages that the inner cavity of the battery module shell is isolated from the external air through the sealant by virtue of the battery module shell and the battery module end cover, so that even if the tab of the soft package battery cell in the battery module shell is unglued or the sealant is cracked, the soft package battery cell can still work, and the battery module is safe and reliable. Therefore, the service lives of the soft package battery cell, the battery module and the battery pack are prolonged.

Description

Technical Field

[0001] The technical field involved in this patent is a new type of battery module and battery pack in the lithium-ion soft-pack battery grouping technology. Background Art

[0002] As a device with good safety performance, high mass energy density and flexible size design, soft-pack batteries have been widely used in mobile phones, notebooks, electric vehicles, energy storage, electric ships, power tools, wearable devices and other fields.

[0003] In the prior art, a soft-pack battery generally includes a bare core formed by stacking battery cell pole pieces, a tab assembly connected to the bare core, and a packaging bag (aluminum-plastic film or steel-plastic film) that encapsulates the bare core. The tab assembly includes a tab sheet made of metal material and a tab film made of non-metal material that can be bonded to metal parts and non-metal parts after hot melting. The tab film is used to connect the tab sheet and the packaging bag to ensure that the soft-pack battery does not leak and prevent the tab sheet and the packaging bag from short-circuiting.

[0004] However, as the demand for the charge and discharge rates of soft-pack batteries continues to increase, the temperature rise of the tab assembly is relatively large. After a period of use, the soft-pack batteries in the related art are prone to poor sealing such as debonding or cracking at the tab assembly. Utility Model Content

[0005] In view of the shortcomings and problems of the prior art, the technical problem to be solved by the utility model is to provide a new type of battery module, including a battery core, wherein the battery core is a soft-pack battery core, and the soft-pack battery core at least includes a bare core formed by stacking the positive and negative pole pieces of the battery and the battery separator, a pole ear, a pole ear film and a stacked packaging structure bonded by an aluminum-plastic film;

[0006] The shell comprises an integrally formed or welded main body with an opening at at least one end, matching the shape of the battery core, and the average thickness of the inner cavity of the main body is at least a positive integer multiple greater than the thickness of the battery core;

[0007] The end cover comprises a main body made of an insulating material or a composite of an insulating material and a metal material, the end cover is provided with a strip-shaped narrow hole through which the battery cell tab can pass, and the surface of the strip-shaped narrow hole and the area where the battery cell tab contacts have an insulating structure;

[0008] The tab connection sheet is made of a conductive metal material and is provided with a narrow strip hole through which the tab of the battery cell can pass; the thickness and width of the tab connection sheet meet the current carrying capacity of the battery cells after being connected in parallel or in series;

[0009] The battery cells are stacked to form a battery cell stack block, and the tabs are connected to each other;

[0010] The tabs of the battery cell pass through the narrow strip holes on the end cover, and then pass through the narrow strip holes of the tab connecting piece; the tab connecting piece fits with the end cover, and the end cover fits with the shell; the tabs of the battery cell are welded to the tab connecting piece, that is, the battery cells are electrically connected in parallel or in series;

[0011] The shell or the end cover is provided with a glue injection hole, and the insulating sealant is injected through the glue injection hole, the insulating sealant fills the strip-shaped narrow hole on the end cover, and the insulating sealant fills the gap between the shell and the end cover; the shell and the end cover are welded or glued;

[0012] The insulating sealant is selected from insulating structural adhesive or insulating and flame-retardant structural adhesive

[0013] The shell includes an integrally formed or welded main body with an opening at least at one end, which matches the appearance of the battery cell, but the average thickness of the inner cavity of the main body is at least a positive integer multiple greater than the thickness of the battery cell, so that several battery cells can be accommodated in the main body at the same time, thereby improving the overall volume energy density.

[0014] The end cover is provided with a strip-shaped narrow hole through which the battery cell tab can pass, and the surface of the strip-shaped narrow hole and the area in contact with the battery cell tab have an insulating structure; the battery cell tab is fixed by passing through the strip-shaped narrow hole, and the part in contact with the battery cell tab is an insulating structure, so it has good fixing performance while maintaining strong insulation ability.

[0015] The tab connecting piece is made of a conductive metal material and is provided with a narrow strip hole through which the tab of the battery cell can pass; the thickness and width of the tab connecting piece meet the current carrying capacity of the battery cells after being connected in parallel or in series; a tab connecting piece with a certain thickness can have a better current carrying capacity.

[0016] The tabs of the battery cell pass through the narrow strip holes on the end cover, and then pass through the narrow strip holes of the tab connecting piece; the tab connecting piece fits with the end cover, and the end cover fits with the shell; the tabs of the battery cell are welded to the tab connecting piece to achieve parallel or series electrical connection between the battery cells;

[0017] The shell or the end cover is provided with a glue injection hole, and the insulating sealant is injected through the glue injection hole, the insulating sealant fills the strip-shaped narrow hole on the end cover, and the insulating sealant fills the gap between the shell and the end cover; the shell and the end cover can be welded;

[0018] The insulating sealant is selected from insulating structural adhesive or insulating and flame-retardant structural adhesive.

[0019] By passing the tab of the battery cell through the narrow hole on the end cover and then through the narrow hole of the tab connecting plate, the battery cell and the connecting plate can be effectively connected, while minimizing the volume of the component and making more efficient use of space.

[0020] The fitting of the tab connector and the end cap, as well as the fitting of the end cap and the housing, can enhance the stability and sealing of the connection, thereby effectively preventing the battery assembly from loosening or leaking during use, and improving the reliability of the battery assembly. At the same time, by adopting the welding connection between the tabs and the tab connectors and the parallel or series electrical connection between the cells, the manufacturing process can be simplified, the production cost can be reduced, and the production efficiency can be improved.

[0021] By setting a glue injection hole at a certain position of the end cover or the shell near the end cover and injecting insulating sealant, the pole ear position of the battery module is sealed as a whole, and even if the battery module is subjected to severe vibration during use, the pole ear position will not loosen; and the narrow hole on the end cover and the gap between the shell and the end cover can be effectively filled, thereby improving the sealing performance of the battery assembly, effectively preventing the leakage of electrolyte inside the battery or the entry of the external environment, and enhancing the safety and stability of the battery.

[0022] At the same time, the injection of insulating sealant can effectively improve the insulation performance of battery components, reduce the risk of possible short circuits, and extend the service life of the battery.

[0023] In one embodiment of the utility model, the housing is a single chamber, and one or more insulated battery cell stack blocks are installed in the chamber. By placing the battery cell stack blocks in a single chamber, the space can be used more effectively, the overall volume of the battery assembly can be reduced, making it more compact, and the volume energy density of the battery pack can be improved. Since the battery cell stack blocks are insulated from each other in the chamber, the risk of short circuit between the battery cells can be effectively reduced, and the safety and stability of the battery assembly can be improved.

[0024] In one embodiment of the utility model, the shell includes a plurality of chambers, and the chambers are divided; wherein one or more insulated battery cell stack blocks are installed in each of the divided chambers. By providing a plurality of divided chambers in the shell, and installing insulated battery cell stack blocks in each chamber, the risk of short circuit between battery cells can be effectively reduced, and the safety and stability of the battery assembly can be improved. Installing the battery cell stack blocks in each of the divided chambers is conducive to optimizing the layout of the battery cells, reducing the spatial conflict between the battery cells, and improving the overall compactness and volume utilization of the battery assembly.

[0025] In one embodiment of the utility model, the insulating sealant wraps the area where the tabs of all the cells in the battery module are stacked and packaged and connected to the aluminum-plastic film. The wrapping of the insulating sealant can effectively protect the tabs of all the cells in the battery module, prevent short circuits and electrical failures, thereby improving the safety and stability of the battery module. The wrapping of the sealant can effectively prevent the internal tab area of ​​the battery from corrosion and oxidation due to contact with air or the external environment, extend the service life of the battery, and help prevent leakage and circuit failures.

[0026] At the same time, the layer formed by the sealant can provide additional mechanical protection to prevent the battery cell's ears from being damaged by external impact or extrusion, further enhancing the durability of the battery.

[0027] In one embodiment of the utility model, the insulating adhesive is selected from at least one of epoxy resin adhesive, acrylate adhesive, polyurethane adhesive, urethane adhesive, silicone adhesive, amino formaldehyde resin adhesive, polyether ketone adhesive and polyimide adhesive. They all have good insulation properties, can effectively isolate the cells in the battery module, and prevent circuit short circuits and electrical failures. They also have good temperature resistance, can remain stable in a wide temperature range, and are suitable for various working environments and usage conditions.

[0028] The utility model also provides a battery pack, including a new battery module, a battery management system and a battery box, wherein the new battery module is arranged in the battery box, adjacent new battery modules are connected in parallel or in series through metal connecting pieces, a total positive terminal and a total negative terminal are arranged on the new battery module, and the battery box includes a total positive connector, a total negative connector and a battery management system data signal line connector. This technical solution combines the new battery module with the battery management system and the battery box, realizes parallel or series connection between modules through efficient connecting pieces, and is equipped with a total positive terminal, a total negative terminal and a connector to achieve reliable electrical connection and convenient battery management, optimizes the structural design of the battery pack, and improves the overall performance and ease of use.

[0029] In one embodiment of the utility model, the battery management system harness is selected from one of a harness consisting of multiple wires, a wiring harness, and a flexible printed circuit board harness. By selecting a harness consisting of multiple wires, a wiring harness, or a flexible printed circuit board harness, the design and layout of the battery management system can be flexibly implemented according to specific needs and application scenarios, thereby improving the overall reliability, stability, and flexibility of the battery pack, while reducing the manufacturing cost and maintenance difficulty of the harness, and providing better protection for the performance and efficiency of the battery system.

[0030] In one embodiment of the utility model, the battery box is selected from a bottom box and a box cover formed by one piece or welding, and a sealing ring is arranged between the bottom box and the box cover. The battery bottom box and the box cover formed by one piece or welding are used, and the sealing ring is arranged in cooperation to achieve different levels of dustproof and waterproof requirements, effectively protect the battery module and the battery management system from the influence of the external environment, improve the stability and reliability of the battery system, extend the service life of the battery, simplify the manufacturing process, and reduce the maintenance cost and difficulty of repair.

[0031] In one embodiment of the utility model, the bottom of the battery box or the side of the box body is selected from an integrally formed or welded liquid heat exchange plate, and the liquid heat exchange plate introduces a low-temperature liquid to cool the battery module, and introduces a high-temperature liquid to heat the battery module. By using an integrally formed or welded liquid heat exchange plate as the bottom or side of the battery box, effective cooling and heating control of the battery module can be achieved. The introduction of low-temperature liquid can effectively reduce the operating temperature of the battery module and improve the safety and cycle life of the battery system, while the introduction of high-temperature liquid can quickly heat the battery module in a cold environment, improving the starting performance and energy output. This design not only ensures the stability and reliability of the battery system in various environments, but also improves the working efficiency and performance of the battery, so that applications such as electric vehicles or energy storage systems have more outstanding performance and reliability.

[0032] In one embodiment of the utility model, the battery box cover is selected from a metal material or a non-metal material. Metal or non-metal material can be selected as the battery box cover according to specific needs and application scenarios. The metal box cover has higher strength and durability, and can provide better mechanical protection and impact resistance; while the non-metal box cover usually has lighter weight and better insulation performance, which helps to reduce the overall weight of the battery box. Therefore, this design can flexibly meet the needs of different users, while providing a variety of options to optimize the structural design and performance of the battery box.

[0033] In one embodiment of the utility model, the heat exchange liquid of the battery box is selected from at least one of water, ethylene glycol, propylene glycol, silicone oil, transformer oil, fluoropolyether, a mixed liquid of water and ethylene glycol, and a mixed liquid of water and propylene glycol.

[0034] By selecting different heat exchange liquids, effective thermal management of the battery case can be achieved according to the specific working environment and requirements. Mixed liquids such as a mixture of pure water and ethylene glycol or a mixture of pure water and propylene glycol have good thermal conductivity and antifreeze properties, and are suitable for providing stable heating and cooling effects in cold environments; silicone oil and transformer oil have good insulation properties and thermal stability, and are suitable for stable heating or cooling control of battery modules; and fluoropolyether heat transfer fluids have excellent thermal conductivity and chemical stability, and are suitable for efficient heat conduction and heat dissipation of battery modules. Therefore, this technical solution can select appropriate heat exchange liquids according to actual needs, achieve effective thermal management of the battery case, and improve the performance and reliability of the battery system. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of a soft-pack battery cell disclosed in the utility model;

[0036] Figure 2 It is a schematic diagram of a tab and a tab film combined with each other disclosed in the utility model;

[0037] Figure 3 It is a schematic diagram of a novel battery module disclosed by the utility model;

[0038] Figure 4 It is a schematic diagram of the combination of an end cover and a tab connecting piece disclosed in the utility model;

[0039] Figure 5 It is a schematic diagram of a main body and an end cover combined with each other disclosed in the utility model;

[0040] Figure 6 It is a schematic diagram of a battery cell stacking block disclosed in the utility model;

[0041] Figure 7 It is a schematic diagram of a housing disclosed in the utility model;

[0042] Figure 8 It is a schematic diagram of a battery pack disclosed in the utility model;

[0043] Among them, 1. soft-pack battery cell, 11. pole ear, 12. pole ear film, 13. aluminum-plastic film, 2. shell, 21. main body, 3. end cover, 31. glue injection hole, 4. pole ear connecting piece, 5. strip narrow hole, 6. packaging structure of battery cell stack, 7. battery box, 71. total positive connector, 72. total negative connector, 74. battery management system data signal line connector, 73. manual maintenance switch MSD, 8. new battery module. Implementation

[0044] Example 1

[0045] like Figure 1 to Figure 6 As shown, this embodiment discloses a new type of battery module 8, including:

[0046] The soft-pack battery cell 1 at least comprises a bare core (in an aluminum-plastic film, not shown in the figure) formed by stacking a battery electrode and a battery separator, a tab 11, a tab film 12 and a laminated packaging structure bonded by an aluminum-plastic film 13;

[0047] The housing 2 includes an integrally formed or welded main body 21 with an opening at at least one end, which matches the shape of the battery cell, but the average thickness of the inner cavity of the main body 21 is at least a positive integer multiple greater than the thickness of the battery cell;

[0048] The end cover 3 is made of an insulating material or a composite of an insulating material and a metal material. The end cover 3 is provided with a strip-shaped narrow hole 5 through which the battery cell tab 11 can pass. The surface of the strip-shaped narrow hole 5 and the area where the battery cell tab 11 contacts have an insulating structure.

[0049] The tab connecting sheet 4 is made of a metal material with excellent conductive properties and is provided with a strip-shaped narrow hole 5 through which the tab 11 of the battery cell can pass; a plurality of soft-pack battery cells are stacked to form a battery cell stacking block, and the tabs 11 are connected to each other;

[0050] The cell tab 11 passes through the narrow strip hole 5 on the end cover 3, and then passes through the narrow strip hole 5 of the tab connecting piece 4; the tab connecting piece 4 fits with the end cover 3, and the end cover 3 fits with the housing 2; the cell tab 11 is welded to the tab connecting piece 4 to achieve parallel or series electrical connection between the cells;

[0051] A glue injection hole 31 is provided on the end cover 3 or at a position of the shell 2 near the end cover 3, and insulating sealant is injected through the glue injection hole 31, so that the insulating sealant fills the strip narrow hole 5 on the end cover 3, and the insulating sealant fills the gap between the shell 2 and the end cover 3; the shell 2 and the end cover 3 are welded or glued; the insulating sealant is an insulating and flame-retardant structural adhesive.

[0052] Example 2

[0053] like Figure 1-Figure 7 As shown, this embodiment discloses a new type of battery module 8, including:

[0054] The soft-pack battery cell 1 at least comprises a bare core (in an aluminum-plastic film, not shown in the figure) formed by stacking a battery pole piece and a battery separator, a pole ear 11, a pole ear film 12 and a laminated packaging structure bonded by the aluminum-plastic film;

[0055] The housing 2 includes an integrally formed main body 21 with an opening at at least one end, which matches the shape of the battery cell, but the average thickness of the inner cavity of the main body 21 is at least a positive integer multiple greater than the thickness of the battery cell;

[0056] The end cover 3 is made of an insulating material or a composite of an insulating material and a metal material. The end cover 3 is provided with a strip-shaped narrow hole 5 through which the battery cell tab 11 can pass. The surface of the strip-shaped narrow hole 5 and the area where the battery cell tab 11 contacts have an insulating structure.

[0057] The tab connecting sheet 4 is made of a metal material with excellent conductive properties and is provided with a strip-shaped narrow hole 5 through which the tab 11 of the battery cell can pass; the battery cells are stacked to form a battery cell stacking block, and the tabs 11 are connected to each other;

[0058] The cell tab 11 passes through the narrow strip hole 5 on the end cover 3, and then passes through the narrow strip hole 5 of the tab connecting piece 4; the tab connecting piece 4 fits with the end cover 3, and the end cover 3 fits with the housing 2; the cell tab 11 is welded to the tab connecting piece 4 to achieve parallel or series electrical connection between the cells;

[0059] A glue injection hole 31 is provided on the end cover 3 or at a position of the shell 2 near the end cover 3, and insulating sealant is injected through the glue injection hole 31, so that the insulating sealant fills the strip narrow hole 5 on the end cover 3, and the insulating sealant fills the packaging structure 6 of the battery cell stack and the gap between the shell 2 and the end cover 3; the shell 2 and the end cover 3 are welded or glued; the insulating sealant is an insulating structural glue.

[0060] The main body 21 includes two chambers, and the chambers are divided; a battery cell stacking block is installed in each of the divided chambers.

[0061] Example 3

[0062] like Figure 8 As shown, this embodiment discloses a battery pack, including a new battery module 8 of any one of Embodiments 1-2, a battery management system wiring harness (not shown in the figure) and a battery box 7, the new battery module 8 is arranged in the battery box 7, adjacent new battery modules 8 are connected in parallel or in series through connecting plates, a total positive terminal and a total negative terminal are arranged on the new battery module 8, and the battery box 7 includes a total positive connector 71, a total negative connector 72 and a battery management system data signal line connector 74, and a manual maintenance switch MSD73.

[0063] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0064] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the first premise of the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A new type of battery module, characterized in that: include, A battery cell, wherein the battery cell is a soft-pack battery cell, and the soft-pack battery cell at least comprises a bare core formed by stacking positive and negative electrode sheets of a battery and a battery separator, a tab, a tab film and a laminated packaging structure bonded by an aluminum-plastic film; The shell comprises an integrally formed or welded main body with an opening at at least one end, matching the shape of the battery core, and the average thickness of the inner cavity of the main body is at least a positive integer multiple greater than the thickness of the battery core; The end cover comprises a main body made of insulating material or a composite of insulating material and metal material, the end cover is provided with a strip-shaped narrow hole through which the tab of the battery cell can pass, and the surface of the strip-shaped narrow hole and the area where the tab of the battery cell contacts have an insulating structure; The tab connecting sheet is made of a conductive metal material and is provided with a strip-shaped narrow hole through which the tab of the battery cell can pass; The battery cells are stacked to form a battery cell stack block, and the tabs are connected to each other; The tabs of the battery cell pass through the narrow strip holes on the end cover, and then pass through the narrow strip holes of the tab connecting piece; the tab connecting piece fits with the end cover, and the end cover fits with the shell; the tabs of the battery cell are welded to the tab connecting piece, that is, the battery cells are electrically connected in parallel or in series; A glue injection hole is arranged on the end cover or the shell near the end cover, and an insulating sealant is injected through the glue injection hole. The insulating sealant fills the narrow strip hole on the end cover, and the insulating sealant fills the gap between the shell and the end cover; the shell and the end cover are connected by welding or gluing; The insulating sealant is selected from insulating structural adhesive or insulating and flame-retardant structural adhesive.

2. The battery module according to claim 1, characterized in that: The shell includes a plurality of chambers, and the chambers are divided; wherein one or more battery cell stacking blocks insulated from each other are installed in each of the divided chambers.

3. The novel battery module as claimed in claim 2, characterized in that: The insulating sealant wraps the tab stacking packaging area of ​​all the cells in the battery module.

4. The novel battery module according to any one of claims 1 to 3, characterized in that: The outer surface of the main body of the shell is a fin or a light plane with a self-heating function.

5. A battery pack, characterized in that: It comprises the novel battery module, battery management system and battery box as described in any one of claims 1 to 4, wherein the novel battery module is arranged in the battery box, adjacent novel battery modules are connected in parallel or in series through connecting plates, a total positive terminal and a total negative terminal are arranged on the novel battery module, and the battery box comprises a total positive connector, a total negative connector and a battery management system data signal line connector.

6. The battery pack according to claim 5, wherein: The battery management system wiring harness is selected from one of a wiring harness consisting of multiple wires, a wiring harness and a flexible printed circuit board wiring harness.

7. The battery pack according to claim 5, wherein: The battery box is selected from a bottom box and a box cover that are integrally formed or welded, and a sealing ring is arranged between the bottom box and the box cover.

8. The battery pack according to claim 5, wherein: The bottom or side of the battery box is selected from a liquid heat exchange plate formed in one piece or welded.

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