Power nickel-metal hydride battery

Abstract

The utility model discloses a power nickel-metal hydride battery which comprises an outer shell, the outer shell comprises a shell body with at least one face open and a sealing cover, a plurality of mutually independent cavities are formed in the outer shell through partition plates, and a battery cell is placed in each cavity. A positive collector plate and a negative collector plate of the battery cell penetrate out of the shell through a through hole in the sealing cover and form an electric connection structure outside, a glue injection groove is formed in the periphery of the electric connection structure of the sealing cover, and sealant is poured into the glue injection groove to seal the whole electric connection structure. The positive collector plate and the negative collector plate are led out of the shell to form an electric connection structure, each cavity is only provided with the through hole to be communicated with the outside, all the cavities are not communicated at all, the through holes are sealed in a sealant pouring mode, the connection and sealing technology is simple, special equipment is not needed, the input cost is low, connection is reliable, and the service life is long. The utility model has the characteristics of simple structure, high sealing performance, low failure rate and easiness in maintenance, and overcomes the technical problems of high process difficulty and low yield in the prior art.

Description

A type of nickel-metal hydride battery Technical Field

[0001] This utility model belongs to the field of power nickel-metal hydride battery manufacturing technology, and specifically relates to a power nickel-metal hydride battery. Background Technology

[0002] Nickel-metal hydride batteries are one of the more mature power batteries used in hybrid vehicles. They have advantages such as excellent low-temperature performance, good power performance, resistance to overcharge and over-discharge, resistance to high-temperature use, and low risk of thermal runaway. However, they also have disadvantages such as low nominal voltage and low specific energy. Therefore, improving volumetric energy density within the limited vehicle frame space is the main research direction in this field.

[0003] Currently, one of the main directions for improving volumetric energy density is the fabrication of large-volume, high-capacity nickel-metal hydride batteries. This involves dividing the same casing into multiple independent small chambers, each containing a single battery cell. These cells are then connected in series to form an integrated battery with a higher voltage, effectively increasing the overall energy density. The most mature fabrication process for this type of battery involves creating through-holes in the separators separating adjacent small chambers, embedding sealing rings within these through-holes, and then bonding the positive and negative current collectors of adjacent cells together with the sealing rings to form a sealed and electrically connected structure.

[0004] However, due to the small size of each independent small chamber, typically only 2-3 cm in width (i.e., the welding operation surface), the equipment cost and process control difficulty of this process are extremely high. During the series welding of battery cells, it is required to ensure that the positive and negative current collectors can tightly compress the sealing ring, while the reaction force of the sealing ring must be much lower than the welding tensile strength to ensure both welding and sealing effects. Firstly, this process requires welding equipment and tooling that are small in size but can provide sufficient clamping force to compact the sealing ring and ensure welding effect. It also requires welding operations within a confined space, placing extremely high demands on equipment performance. Often, specialized equipment is required, resulting in high investment costs, and resistance welding is generally the only method for connection. Secondly, due to the limited operating space, welding defects are difficult to detect in a timely manner, easily leading to batch defects and affecting production efficiency and quality stability. Thirdly, the sealing ring is obscured by the current collector, making it difficult to check its proper installation. The process control precision and stability requirements are extremely high. Even minor defects can easily lead to alkaline creep in adjacent chambers during later use, causing internal short circuits and affecting battery safety and lifespan. Currently, only Toyota has mastered this process and applies it to its hybrid vehicles, making it difficult for other companies to replicate, thus limiting the application and promotion of nickel-metal hydride batteries in the electric vehicle sector. Therefore, overcoming this technological bottleneck and developing a more efficient and lower-cost manufacturing process is crucial to promoting the widespread use of nickel-metal hydride batteries.

[0005] Patent CN201310720841.5 attempts to provide an alternative process by directly embedding conductive posts into the separator, and welding the positive and negative current collectors of adjacent cells to the two ends of the conductive posts respectively. This reduces the performance requirements of the welding equipment and lowers equipment costs and operational difficulty. However, because the outer shell is made of plastic and the conductive posts are made of metal, the contact surfaces of the two cannot be completely fused, and small gaps cannot be avoided. Furthermore, the difference in the coefficient of expansion during long-term use can lead to poor sealing of adjacent chambers, resulting in alkali creep and posing a risk of internal short circuits.

[0006] Furthermore, the aforementioned structure of nickel-metal hydride batteries also presents several drawbacks: because the electrical connection structure is located within an internal chamber, maintenance and inspection are extremely inconvenient. If a defect occurs during manufacturing or during use, the location of the faulty cell cannot be accurately pinpointed, necessitating disassembly or disposal of the entire battery, increasing repair costs and time. Therefore, further optimizing the electrical connection structure and sealing process to improve reliability and ease of maintenance is a key technological challenge for nickel-metal hydride batteries. Summary of the Invention

[0007] (I) Technical Issues

[0008] The technical problem to be solved by this utility model is that the existing multi-chamber power nickel-metal hydride battery structure has problems such as high manufacturing process difficulty, high equipment investment cost, difficulty in ensuring process accuracy, high product defect rate, high internal short circuit failure rate, and poor maintainability when defects or faults occur.

[0009] (II) Technical Solution

[0010] This utility model is achieved through the following technical solution:

[0011] This utility model proposes a power nickel-metal hydride battery, including a shell, the shell being divided into multiple independent chambers by a separator, each chamber containing a battery cell, the battery cell being composed of a positive electrode, a separator, and a negative electrode, a positive current collector and a negative current collector are respectively provided on both sides of the width direction of the battery cell, the positive current collector and the negative current collector are electrically connected to the positive electrode or the negative electrode, and the positive current collector and / or negative current collector of adjacent battery cells are respectively located on both sides of the separator;

[0012] The outer casing includes a housing and a cover. The housing is a cavity structure with at least one opening. The partition is disposed inside the housing and divides the interior of the housing into multiple chambers. The two side walls of the housing are provided with terminal posts as output electrodes. The cover is used to close the opening of the housing.

[0013] The outer side of the cover is provided with a glue injection groove, which corresponds to the partition or the side wall of the shell. Each glue injection groove has two through holes penetrating the cover. The through holes correspond one-to-one with the positive current collector or the negative current collector. The positive current collector and the negative current collector extend through the through holes into the glue injection groove. The positive current collector and / or the negative current collector form an electrical connection structure in the glue injection groove. The positive current collector or the negative current collector of the battery cell located at the end forms an electrical connection structure with the terminal post in the glue injection groove. After the electrical connection structure is formed, the glue injection groove is filled with sealant higher than the electrical connection structure. After the positive current collector and the negative current collector of the battery cell pass through the cover, the cover is sealed to the shell, so that multiple independent sealed chambers are formed inside the shell.

[0014] Based on the above technical solutions, by extending the positive and negative current collectors of each cell to the outside of the casing and forming an electrical connection there, and by using a method of filling the injection tank with sealant, the problems of inconvenient maintenance and poor sealing of the internal cavity electrical connection structure are effectively solved. This significantly improves the overall reliability and maintainability of the battery, and reduces the failure rate and maintenance costs. At the same time, this design adopts a pre-welding and post-sealing manufacturing process, which simplifies the electrical connection process, reduces equipment investment, and makes it easy to observe the welding and sealing quality in real time, improving process accuracy, reducing product defect rate, and ensuring the stability and safety of the battery in long-term use. Furthermore, the method of extending the positive and negative current collectors to the outside of the casing is more conducive to dissipating the heat generated by the cell to the outside, avoiding heat accumulation in the cavity, thereby improving the safety and stability of the battery.

[0015] Furthermore, the terminal posts are located inside the two side walls of the housing and are integrally injection molded with the housing. Each terminal post includes an external positive or negative terminal post and an extension piece electrically connected to it. The cover has through holes that match the extension pieces. The extension pieces extend through the through holes into the injection groove and form an electrical connection with the positive or negative current collector of the end cell. This structure, by integrally injection molding the terminal posts into the housing, can effectively prevent the terminal posts from directly communicating with the chamber and contacting the electrolyte inside the chamber. No additional sealing structure design is required at the terminal posts, resulting in high sealing performance, preventing alkali creep, and also preventing corrosion of the terminal posts.

[0016] Preferably, the shell and the partition are integrally injection molded, forming multiple chambers with only the upper opening. There is one cap for closing the opening of the chambers. The cap is provided with a safety valve corresponding to each chamber. This design only requires one sealing to complete the sealing of the entire shell, and the process is simpler.

[0017] Preferably, the shell and the partition are integrally injection molded, forming multiple chambers with openings at both ends inside. The cover includes a top cover and a bottom cover for closing the chamber openings. The top cover is provided with a safety valve port corresponding to each chamber. Both the top cover and the bottom cover are provided with through holes and injection grooves. The positive current collector and negative current collector of the battery cell pass through the corresponding through holes on the top cover and the bottom cover, and form electrical connection structures in the injection grooves of the top cover and the bottom cover respectively. The purpose of this design is to form electrical connections at the top and bottom of the shell at the same time, shorten the current-carrying path inside the battery cell, reduce internal resistance, improve the uniformity of current distribution inside the battery cell, and help improve the overall performance of the battery.

[0018] More preferably, the bottom cover has an upwardly protruding cell support plate, which extends into each chamber and contacts the bottom of the cell. The support plate is used to support the cell and is distributed in a grid pattern on the bottom cover. This design aims to provide additional support for the cell and avoid damage caused by insufficient support at the bottom of the cell, such as cell deformation or electrode misalignment.

[0019] Furthermore, the glue injection groove is provided with an electrode plate, and the positive current collector and / or negative current collector in the same glue injection groove are respectively connected to both sides of the electrode plate. The positive current collector and / or negative current collector together with the electrode plate form an electrical connection structure. This design eliminates the need for bending operations on the positive and negative current collectors, and avoids the tension between the current collector and the electrode plate caused by bending operations, which would reduce the connection reliability. At the same time, the connection method also facilitates the use of positive and negative current collectors with larger thicknesses.

[0020] Furthermore, the thickness of the positive current collector and the negative current collector is not less than 0.4mm. This design helps to give the positive current collector and the negative current collector a certain rigidity, making them less prone to deformation when passing through holes, which helps to reduce the difficulty of the process. At the same time, it can also improve the current carrying capacity of the current collector, reduce the current resistance and heat generation of the cells in each chamber, thereby improving the overall charging and discharging efficiency of the battery.

[0021] Preferably, after the positive current collector and / or negative current collector pass through the through hole, the positive current collector and negative current collector in the same glue injection groove form a bending structure towards the center of the glue injection groove, and the bending structures overlap and are welded to form the electrical connection structure. This design can reduce the number of welding operations and thus simplify the welding process. This design is suitable for current collectors and extension sheets with relatively soft materials and small thickness.

[0022] Furthermore, when the cover and the housing need to be sealed together, the cover and the housing are fused together into a single structure by hot plate welding. This design helps to improve the overall sealing performance of the battery and enhance the overall structural strength of the battery.

[0023] Furthermore, a sealing element is provided at the through hole. The sealing element is T-shaped or I-shaped. The purpose of this design is to allow the positive current collector, negative current collector, or extension plate to easily pass through the through hole and form an elastic seal between them, thereby preventing the sealant from flowing into the cavity from the contact gap between the two when the sealant is poured into the injection tank.

[0024] Furthermore, after the sealant cures, a reserved hole communicating with the electrical connection structure is formed in the injection groove. The reserved hole is used to detect the electrical connection status of different sections. The purpose of this design is to quickly locate the fault point through the reserved hole, which facilitates maintenance, repair and anomaly analysis, improves the maintainability of the battery and helps reduce maintenance costs.

[0025] (III) Beneficial Effects

[0026] At least one technical solution of this utility model has the following advantages or beneficial effects:

[0027] 1) By extending the positive and negative current collectors of each cell to the outside of the casing and forming an electrical connection on the outside, each chamber is connected to the outside only through a through-hole, while the chambers are completely isolated from each other. The through-holes are sealed by filling a sealant injection tank, effectively solving the processing difficulties caused by space constraints when placing the cell's electrical connection structure inside the casing, as well as quality issues such as poor welding and sealing. On the one hand, it achieves highly reliable electrical connections and absolute sealing and relative independence between chambers without the need for expensive specialized equipment, greatly reducing production costs. This approach reduces costs and eliminates the risk of internal short circuits such as alkali creep and electrolyte interconnection between chambers, improving the overall reliability and safety of the battery cell. Furthermore, it simplifies the manufacturing process of multi-chamber, high-capacity nickel-metal hydride power batteries, making process quality monitoring easier and more observable. It effectively solves the problems of poor sealing and undetectable sealing status when the battery cell's electrical connection structure is located inside the casing, thus effectively reducing the failure rate during use. It also increases the selectivity of the electrical connection process, ensuring overall battery reliability and controllable production costs, and overcoming technical difficulties that are difficult to achieve or have low yield rates with existing technologies.

[0028] 2) By adopting an electrical connection on the outside of the casing, it is easier to quickly locate and detect the fault point when a fault occurs, which facilitates subsequent maintenance and quality anomaly analysis. It also facilitates the targeted recycling of non-faulty parts, improves the secondary utilization rate of resources, and is more environmentally friendly.

[0029] 3) By extending the positive and negative current collectors of each cell to the outside of the casing, and considering the thickness and material of the current collectors, it is easier to quickly dissipate the heat generated by the cell to the outside, avoid heat accumulation in the cavity, and improve the safety and stability of the battery.

[0030] 4) By making each cell form an external electrical connection at both the top and bottom of the casing, the current path inside the cell is effectively shortened, which can effectively improve the uniformity of current distribution inside the cell and thus improve the overall performance of the battery. Attached Figure Description

[0031] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0032] Figure 1 is a schematic diagram of the exploded structure of Embodiment 1 of the present invention;

[0033] Figure 2 is a cross-sectional structural diagram of Embodiment 1 of the present invention;

[0034] Figure 3 is a top view of the capping diagram of Embodiment 1 of the present invention;

[0035] Figure 4 is a cross-sectional structural diagram of Embodiment 2 of the present invention;

[0036] Figure 5 is a schematic diagram of the bottom cover support plate of Embodiment 2 of the present invention;

[0037] Figure 6 is a schematic diagram of the electrode connection structure in Embodiment 3 of the present invention;

[0038] In the diagram: Chamber 101; Outer shell 1; Shell 11; Cover 12; Top cover 121; Bottom cover 122; Cell support plate 123; Separator 13; Cover plate 14; Cell 2; Positive current collector 21; Negative current collector 22; Glue injection groove 3; Through hole 4; Safety valve 5; Electrical connection structure 6; Electrode 61; Bending structure 62; Terminal post 7; Positive post 71; Negative post 72; Extension plate 73. Detailed Implementation

[0039] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In some embodiments, certain technical features well-known in the art have not been described to avoid confusion with the present invention.

[0040] The present invention will be further described in detail below with reference to embodiments, but the implementation of the present invention is not limited thereto.

[0041] Example 1

[0042] This invention provides a power nickel-metal hydride battery: it includes a shell 1, a housing 11 with at least one opening, and a cover 12. The shell 1 has a plurality of independent chambers 101, and each chamber 101 contains a battery cell 2. The positive current collector 21 and the negative current collector 22 of the battery cell 2 extend out of the shell 1 and form an electrical connection structure 6 on the outside. The outer periphery of the electrical connection structure 6 is provided with a glue injection groove 3 to accommodate the electrical connection structure 6. After the electrical connection structure 6 is formed, the glue injection groove 3 is filled with sealant to seal the entire electrical connection structure 6, forming an absolute seal for each chamber 101.

[0043] As shown in Figures 1 and 2, the specific structure of the power nickel-metal hydride battery in this embodiment includes:

[0044] The outer casing 1 includes a housing 11 and a cover 12. The housing 11 is a cavity structure with an opening only at the top. An integrally injection-molded partition 13 is provided inside the housing 11, dividing the interior of the housing 11 into multiple independent chambers 101, each with an opening only at the top. The cover 12 is a single unit. When the battery cell 2 is placed inside the chamber, the cover 12 is fused to the housing 11 and the partition 13 using hot-plate welding to seal the openings of the housing 11 and each chamber 101, creating independent spaces for each chamber and improving the overall sealing of the battery. Both the outer casing 1 and the partition 13 are made of injection-molded material.

[0045] Each independent chamber 101 contains a battery cell 2, which is composed of positive and negative electrode plates stacked sequentially with a diaphragm separating them. A positive current collector 21 and a negative current collector 22 are respectively located on both sides of the battery cell 2 in the width direction. The positive current collector 21 is connected to the tab of the positive electrode plate by ultrasonic welding, resistance welding, or other welding methods. The negative current collector 22 is welded to the tab of the negative electrode plate. The lower ends of the positive current collector 21 and the negative current collector 22 are in contact with the bottom of the housing 11, and their upper ends are positioned above the upper surface of the cover 12.

[0046] Depending on the series or parallel connection requirements, the positive current collector 21 and / or negative current collector 22 of adjacent cells 2 are respectively arranged on both sides of the separator 13. Specifically, when cells 2 need to be connected in series, the positive current collector 21 of the left cell 2 is adjacent to the left side of the separator 13, and the negative current collector 22 of the right cell 2 is adjacent to the right side of the separator 13. When cells 2 need to be connected in parallel, the positive current collector 21 of the left cell 2 is adjacent to the left side of the separator 13, and the positive current collector 21 of the right cell 2 is adjacent to the right side of the separator 13, or the negative current collector 22 of the left cell 2 is adjacent to the left side of the separator 13, and the negative current collector 22 of the right cell 2 is adjacent to the right side of the separator 13. When cells 2 need to be combined in series or parallel, they can be arranged according to the aforementioned series or parallel connection methods. In this embodiment, as shown in FIG1, the battery cells 2 in each chamber 101 are arranged in series with each other, that is, the positive current collector 21 and negative current collector 22 of adjacent battery cells 2 are close to each other and distributed adjacent to the same partition 13. The following scheme is further developed based on this.

[0047] The housing 11 has integrally injection-molded terminal posts 7 on both sides. Each terminal post 7 includes an external positive terminal post 71 or a negative terminal post 72, and an extension piece 73 electrically connected to it. The upper end of the extension piece 73 passes through the cover 12 and is exposed on the outer side of the cover 12. The extension piece 73 electrically connected to the external positive terminal post 71 is electrically connected to the positive current collector 21 of its adjacent cell 2, and the extension piece 73 electrically connected to the external negative terminal post 72 is electrically connected to the negative current collector 22 of its adjacent cell 2.

[0048] The outer side of the cover 12 is provided with a glue injection groove 3, which corresponds to the side wall of the partition 13 or the housing 11. Each glue injection groove 3 has two through holes 4 penetrating the cover 12. The through holes 4 correspond one-to-one with the positive current collector 21, the negative current collector 22, or the extension piece 73. When the cover 12 is fastened to the housing 11, the positive current collector 21, the negative current collector 22, and the extension piece 73 pass through the corresponding through holes 4 and extend into the glue injection groove 3. The positive current collector 21 and the negative current collector 22, or the positive current collector 21 and the extension piece 73, or the negative current collector 22 and the extension piece 73 located in the same glue injection groove 3 form an electrical connection structure 6 by welding, locking, or other means. After the electrical connection structure 6 is formed, the glue injection groove 3 is filled with sealant higher than the electrical connection structure 6. After the sealant cures, it forms a complete seal for the through holes 4.

[0049] Preferably, as shown in Figure 3, the glue injection groove 3 is provided with an electrode plate 61. The positive electrode current collector 21 and the negative electrode current collector 22, or the positive electrode current collector 21 and the extension piece 73, or the negative electrode current collector 22 and the extension piece 73, in the same glue injection groove 3 are respectively welded or locked to the electrode plate 61 to form an electrical connection, so as to avoid bending the positive electrode current collector 21 and the negative electrode current collector 22, and the tension between the current collector and the electrode plate caused by bending, thereby reducing the connection reliability; at the same time, the connection method also facilitates the use of a larger thickness of the positive electrode current collector 21 and the negative electrode current collector 22.

[0050] Furthermore, the thickness of the positive current collector 21 and the negative current collector 22 is not less than 0.4 mm. More preferably, stainless steel plates or nickel-plated stainless steel plates with a thickness of 1 to 1.5 mm are selected as the positive current collector 21 and the negative current collector 22 to ensure that the positive current collector 21 and the negative current collector 22 have a certain rigidity and are not easily deformed during the process of passing through the through hole 4. This helps to reduce the difficulty of the process and also improves the current carrying capacity of the current collector, reduces the current resistance and heat generation of the cells 2 in each chamber 101, thereby improving the overall charging and discharging efficiency of the battery.

[0051] As a standard configuration for batteries, the cover 12 is also provided with a safety valve port and a temperature sensor port corresponding to each chamber 101. A safety valve 5 (not shown in the attached figure) is installed in each safety valve port, and a temperature sensor (not shown in the attached figure) is installed in each temperature sensor port.

[0052] Preferably, a sealing element (not shown in the figure) is provided at the through hole 4. The sealing element is T-shaped or I-shaped, so that the positive current collector 21, the negative current collector 22 or the extension piece 73 can easily pass through the through hole 4 and form an elastic seal between them, thereby preventing the sealant from flowing into the chamber 101 from the contact gap between the two when the sealant is poured into the injection groove 3.

[0053] Preferably, after the sealant is cured, a reserved hole (not shown in the figure) communicating with the electrical connection structure 6 is formed in the injection groove 3. The reserved hole is used to detect the electrical connection status of different sections so that the fault point can be quickly located when a fault occurs during preparation or use, which facilitates later maintenance, repair and anomaly analysis.

[0054] Preferably, a cover plate 14 is also provided above the cover 12 to protect the cover 12 and support the temperature sensing probe, etc.

[0055] The advantages of this embodiment are as follows: By extending the positive and negative current collectors of each cell 2 to the outside of the outer casing 1 to form an electrical connection, and by filling the injection groove 3 with sealant to form a seal, a highly sealed structure is formed where each chamber 101 is completely isolated from the others. Furthermore, a pre-welding and post-sealing manufacturing process can be used, simplifying the electrical connection and sealing processes. This eliminates the need for expensive additional equipment, and the welding and sealing quality is easily observed in real time. This effectively solves problems such as the difficulty in processing electrical connection structures within internal chambers, the uncontrollable sealing state, and maintenance difficulties, significantly improving the overall reliability and maintainability of the battery, and reducing the failure rate and maintenance costs. Simultaneously, designing the outer casing 1 as a combination of a single-sided open, integrally molded casing 11 and a cover 12 simplifies the assembly process and further reduces the difficulty of process control.

[0056] Example 2

[0057] This embodiment provides a power nickel-metal hydride battery, which differs from Embodiment 1 in that:

[0058] The housing 11 and the internal partition 13 form multiple chambers 101 with openings at both the top and bottom. There are two covers 12, including a top cover 121 and a bottom cover 122. When the battery cell 2 is placed inside the chamber 101, the top cover 121 and the bottom cover 122 are fused together with the housing 11 and the partition 13 via hot plate welding to seal the openings of the housing 11 and each chamber 101. The outer side of the top cover 121 has a glue injection groove 3, through which a through hole 4 and a safety valve port for accommodating a safety valve 5 are provided. The outer side of the bottom cover 122 also has a glue injection groove 3, through which a through hole 4 is provided.

[0059] As shown in Figure 4, the positive current collector 21 and the negative current collector 22 extend upward or downward respectively, passing through the corresponding through holes 4 on the top cover 121 and the bottom cover 122 and extending into the glue injection groove 3 that extends out of the outer side of the top cover 121 and the bottom cover 122. The positive current collector 21 and the negative current collector 22 of the adjacent cells 2 simultaneously form an electrical connection structure 6 in the glue injection groove 3 on the top cover 121 and the bottom cover 122.

[0060] Similarly, the extension piece 73 of the terminal post 7 extends upward or downward within the side wall of the housing 11 and extends into the glue injection groove 3 on the outer side of the top cover 121 and the bottom cover 122. The extension piece 73 and the positive current collector 21 or negative current collector 22 of the adjacent cell 2 also form an electrical connection structure 6 in the glue injection groove 3 on the top cover 121 and the bottom cover 122.

[0061] The electrical connection structure 6 can be formed by using the electrode plate 61 as in Embodiment 1, and by using a positive current collector 21 and a negative current collector 22 with a larger thickness to support the battery cell 2.

[0062] Preferably, as shown in Figures 4 and 5, the bottom cover 122 has an upwardly protruding cell support plate 123. The cell support plate 123 extends into each chamber 101 and contacts the bottom of the cell 2 to support the cell 2. The cell support plate 123 is generally grid-shaped, and strip-shaped clearance holes are formed between the cell support plates 123 to allow the partition plate 13, the positive current collector plate 21 and the negative current collector plate 22 to pass through.

[0063] It should be understood that the downward extension lengths of the positive current collector 21 and the negative current collector 22 are as small as possible to facilitate assembly and form a stable electrical connection, so as to reduce the amount of electrolyte used.

[0064] The advantage of this embodiment is that electrical connections are formed at the top and bottom of the outer casing 1 at the same time, shortening the current-carrying path at the lower end of the positive and negative electrode plates, reducing the overcurrent internal resistance, improving the uniformity of current distribution inside the cell 2, and thus improving the overall performance of the battery.

[0065] Example 3

[0066] This embodiment provides a power nickel-metal hydride battery, which differs from Embodiment 1 or 2 in that:

[0067] As shown in Figure 6, after the positive current collector 21, negative current collector 22 or extension piece 73 pass through the through hole 4, the positive current collector 21, negative current collector 22 or extension piece 73 in the same glue injection groove 3 respectively form a bending structure 62 towards the center of the glue injection groove 3. The bending structures 62 overlap each other and are welded to form the electrical connection structure 6.

[0068] The key feature of this embodiment is that by directly bending and welding the positive current collector 21, negative current collector 22, or extension piece 73, the number of welding operations can be reduced, thereby simplifying the connection process and lowering the defect rate caused by the process. The electrical connection structure of this embodiment is suitable for thin and easily bendable positive and negative current collectors.

[0069] In the description of this invention, it should be noted that the terms "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0070] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the technical scope of the present utility model. Therefore, any minor modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present utility model shall still fall within the protection scope of the present utility model.

Claims

1. A power nickel-metal hydride battery, comprising a casing, the casing being divided into multiple independent chambers by a separator, each chamber containing a battery cell, the battery cell being composed of a positive electrode, a separator, and a negative electrode, a positive current collector and a negative current collector being respectively provided on both sides of the battery cell in the width direction, the positive current collector and the negative current collector being electrically connected to the positive electrode or the negative electrode, the positive current collector and / or negative current collector of adjacent battery cells being respectively disposed on both sides of the separator, characterized in that: The outer casing includes a housing and a cover. The housing is a cavity structure with at least one opening. A partition is disposed inside the housing and divides the interior of the housing into multiple chambers. Terminal posts serving as output electrodes are provided on both side walls of the housing. The cover is sealed to the housing to close the opening of the housing. An adhesive injection groove is provided on the outer side of the cover, corresponding to the partition or the side wall of the housing. Each adhesive injection groove has two through holes penetrating the cover. The through holes correspond one-to-one with a positive current collector or a negative current collector. The positive current collector and / or negative current collector extend through the through holes into the adhesive injection groove. The positive current collector and / or negative current collector form an electrical connection structure in the adhesive injection groove. The positive current collector or negative current collector of the battery cell located at the end forms an electrical connection structure with the terminal post in the adhesive injection groove. The adhesive injection groove is filled with sealant higher than the electrical connection structure to seal the through holes.

2. The power nickel-metal hydride battery according to claim 1, characterized in that: The terminal post is integrally injection molded with the housing. The terminal post includes an external positive or negative terminal post and an extension piece electrically connected to it. The cover is provided with a through hole that matches the extension piece. The extension piece extends through the through hole into the injection groove and forms an electrical connection with the positive or negative current collector of the end cell.

3. A power nickel-metal hydride battery according to claim 1, characterized in that: The housing and the partition are integrally injection molded, forming multiple chambers with only the upper end open. There is one cover for closing the chamber openings, and the cover is provided with a safety valve corresponding to each chamber.

4. A power nickel-metal hydride battery according to claim 1, characterized in that: The housing and the partition are integrally injection molded, forming multiple chambers with openings at both ends inside. The cover includes a top cover and a bottom cover for sealing the chamber openings. The top cover is provided with a safety valve port corresponding to each chamber. Both the top cover and the bottom cover are provided with through holes and injection grooves. The positive current collector and negative current collector of the battery cell pass through the corresponding through holes on the top cover and the bottom cover, and form electrical connection structures in the injection grooves of the top cover and the bottom cover respectively.

5. A power nickel-metal hydride battery according to claim 4, characterized in that: The bottom cover has an upward protrusion with a cell support plate. The cell support plate extends into each chamber and contacts the bottom of the cell. The support plate is used to support the cell and is distributed in a grid pattern on the bottom cover.

6. A power nickel-metal hydride battery according to claim 3 or 4, characterized in that: The glue injection tank is provided with an electrode plate. The positive electrode current collector and / or negative electrode current collector in the same glue injection tank are respectively connected to both sides of the electrode plate. The positive electrode current collector and / or negative electrode current collector together with the electrode plate form an electrical connection structure.

7. A power nickel-metal hydride battery according to claim 6, characterized in that: The thickness of the positive current collector and the negative current collector is not less than 0.4 mm.

8. A power nickel-metal hydride battery according to claim 3 or 4, characterized in that: After the positive current collector and / or negative current collector pass through the through hole, the positive current collector and negative current collector in the same glue injection groove form a bending structure towards the center of the glue injection groove, and the bending structures overlap and are welded to form the electrical connection structure.

9. A power nickel-metal hydride battery according to claim 1, characterized in that: When the cover is sealed to the housing, the cover and the housing are fused together into a single structure by hot plate welding.

10. A power nickel-metal hydride battery according to claim 1, characterized in that: A sealing element is provided at the through hole, and the sealing element is T-shaped or I-shaped.

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