An electrolyte distribution system for a backup battery

Abstract

This invention discloses an electrolyte distribution system for a reserve battery, comprising a reservoir, a gas generator, a sealing assembly, an electrolyte buffer device, a common flow channel, and injection branch pipes. This invention significantly eliminates eddies generated by high-voltage electrolyte jets, appropriately reduces electrolyte flow velocity to decrease radial pulsation, and simultaneously alters the fluid flow rate within each branch pipe by adjusting the fluid resistance, thereby ensuring a substantially uniform electrolyte distribution in each cell, thus improving the injection uniformity between cells. This invention solves the problem of large injection volume deviations between cells in existing technologies, effectively guaranteeing the battery pack's electrical performance; reducing excess electrolyte in the reservoir, improving the battery pack's specific characteristics; and reducing free electrolyte in the common flow channel, lowering the battery pack's leakage current.

Description

Technical Field

[0001] This invention belongs to the field of reserve battery technology, specifically relating to a highly uniform electrolyte distribution system for reserve batteries. Background Technology

[0002] Before use, the electrolyte of the reserve battery is isolated from the battery body and sealed in a reservoir. When activated, it receives an external electrical signal to detonate a gas generator to generate high-pressure gas, which pushes the electrolyte through the electrolyte distribution system into the cavity of each individual battery cell.

[0003] The electrolyte should be injected into the individual cells within a specified time, and the amount of electrolyte injected into each cell should be substantially the same. In the prior art, the uniformity of electrolyte distribution between cells is ±10% to ±25%, with a maximum difference of 20% to 50%.

[0004] A battery pack consists of multiple cells connected in series. Similar to the "weakest link" effect, the cell with the least amount of electrolyte has poor performance and may even affect the performance of the entire battery pack. In order to ensure that the amount of electrolyte injected into the cell with the least amount of electrolyte meets the usage requirements, the total amount of electrolyte in the reservoir needs to be increased. This results in the electrolyte being excessive in most of the other cells, which increases the weight of the battery pack and reduces its specific characteristics.

[0005] Furthermore, the increase in free electrolyte and the amount of electrolyte remaining in the common flow channel lead to an increase in the leakage current of the battery pack. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings and defects mentioned in the background art and to design a novel high-uniformity electrolyte distribution system for storage batteries.

[0007] To achieve the above objectives, the technical solution adopted by the present invention to solve its technical problem is as follows: an electrolyte distribution system for a storage battery, comprising a reservoir containing KOH electrolyte and a gas generator connected to the reservoir, thereby forming an electrolyte storage system. The gas generator consists of a propellant charge and an igniter. A sealing assembly composed of one or more layers of PTFE, PE, or PVC film with a thickness of 0.05–0.30 mm is provided at the bottom opening of the reservoir. The sealing assembly is connected to a common flow channel via an electrolyte buffer device. Below the common flow channel, which is composed of a common flow channel cover and a battery casing, are multiple injection branch pipes corresponding to individual batteries. After the propellant in the gas generator is detonated, high-pressure gas is generated, which acts on the electrolyte and simultaneously squeezes the sealing assembly. After the membrane of the sealing assembly ruptures, the electrolyte enters the electrolyte buffer device and fills the common flow channel composed of the common flow channel cover and the battery casing. Then, it is injected into each individual battery again through injection branch pipes with regional fluid resistance adjustment, completing the electrolyte distribution process.

[0008] The electrolyte distribution system for a storage battery has a sealing component consisting of two PTFE membranes with a thickness of 0.15 to 0.18 mm, which are punched and fixed to the outlet of the reservoir by a compression screw.

[0009] The electrolyte distribution system for a backup battery is described above, wherein the reservoir is made of stainless steel, titanium alloy or other metal-resistant materials that are resistant to strong alkali corrosion and is formed by welding.

[0010] The electrolyte distribution system for a storage battery has an electrolyte buffer device installed directly below the sealing assembly, with the distance between its upper end face and the lower end face of the sealing assembly being ≥5mm.

[0011] The electrolyte distribution system for a storage battery has an injection branch pipe with a circular cross-section hole, a flared hole, or a blood hole, and the end face of the hole has a rounded or chamfered transition.

[0012] The electrolyte distribution system for a storage battery is described above, wherein the electrolyte buffer device is made of non-metallic materials such as nylon, polyvinyl chloride, polytetrafluoroethylene, polyethylene, or polypropylene.

[0013] Compared with the prior art, the advantages of the present invention are:

[0014] 1. The present invention provides an electrolyte buffer device at the outlet of the reservoir. By adjusting the orientation of the circular hole or horn hole on this device to change the flow direction of the electrolyte, the eddy current generated by the high-voltage electrolyte jet can be eliminated, the electrolyte flow rate can be appropriately reduced to reduce the radial pulsation of the electrolyte, thereby improving the uniformity of electrolyte injection between individual cells, reducing the amount of electrolyte carried in the reservoir, and improving the specific characteristics of the battery pack.

[0015] 2. This invention groups the electrolyte injection branch pipes of individual cells and changes the flow velocity of the fluid in the branch pipes by adjusting the fluid resistance of each group of branch pipes, thereby improving the uniformity of electrolyte injection between cells, reducing the free electrolyte in the common flow channel, and reducing the leakage current of the battery pack. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention;

[0017] Figure 2 This is a schematic diagram of the branch flow channel within the electrolyte buffer device of the present invention;

[0018] Figure 3 A schematic diagram of a branch pipeline for regulating fluid resistance in different areas;

[0019] Figure 4 for Figure 3 The left view;

[0020] Figure 5The figure shows the results of the simulated electrolyte distribution test of the system of the present invention.

[0021] The reference numerals in the attached figures are as follows: 1—Gas generator, 2—Liquid reservoir, 3—Electrolyte, 4—Sealing assembly, 5—Electrolyte buffer device, 6—Battery body shell, 7—Injection branch pipe, 8—Common flow channel, 9—Common flow channel cover plate, 10—Single cell bottom cover, 11—Single cell. Detailed Implementation

[0022] To further illustrate the content, features, and effects of this invention, the invention will be described in detail below with reference to the accompanying drawings and examples.

[0023] like Figures 1 to 5 As shown, this invention discloses an electrolyte distribution system for a storage battery, comprising a reservoir 2 for holding electrolyte 3 and a gas generator 1 connected to the reservoir 2, thus forming an electrolyte 3 storage system. A sealing assembly 4 is provided at the bottom opening of the reservoir 2. Below the sealing assembly 4, a common flow channel 8 is connected via an electrolyte buffer device 5. The electrolyte buffer device 5 is installed directly below the sealing assembly 4, and the distance between its upper end face and the lower end face of the sealing assembly 4 is determined according to the size of the sealing assembly 4, and should ideally be ≥5mm. The common flow channel 8... One end is connected to the outlet of the reservoir 2 to allow the electrolyte 3 to flow in, and the other end is connected to the individual battery 11 by a liquid injection branch pipe 7 according to the number of individual batteries. Multiple liquid injection branch pipes 7 are connected below the common flow channel 8. The gas generator 1 consists of a gunpowder pack and an electric igniter. It is preferably a zinc-silver reserve battery product that has been finalized. The gas pressure generated in the 200ml cavity is greater than 0.8MPa and less than 1.5MPa. The type and dosage of gunpowder are determined according to the hydrodynamic characteristics of the electrolyte, especially the pressure head loss and the opening pressure of the sealing component.

[0024] Before the battery pack is activated, the electrolyte 3 can be stored in the reservoir 2 without leakage through the sealing component 4. When the battery pack receives an external electrical activation signal, the propellant in the detonation gas generator 1 generates high-pressure gas. This high-pressure gas acts on the electrolyte 3 and simultaneously squeezes the sealing component 4. When the pressure exceeds the rupture pressure of the sealing component 4, the sealing component 4 opens, and the electrolyte 3 smoothly enters the buffer device 5. After being redistributed by the buffer device 5, the electrolyte 3 fills the common flow channel 8, which is composed of the common flow channel cover plate 9, the battery body shell 6, and the individual cell bottom cover 10. Then, it is injected into each individual cell 11 again through the injection branch pipe 7 with regional fluid resistance adjustment, completing the electrolyte distribution process.

[0025] The liquid reservoir 2 is made of stainless steel, titanium alloy and other resistant metal materials and is welded together. It has good sealing performance and meets the mechanical strength requirements. Moreover, the metal materials used have strong alkali corrosion resistance. The preferred liquid reservoir 2 is made of 1mm thick titanium alloy plate with local reinforcement and is laser welded together. It does not crack or deform under 3.0MPa pressure. After KOH electrolyte 3 is stored in it for 48 hours, there are no traces of leakage.

[0026] The sealing assembly 4 is made of PTFE, PE, or PVC film, and includes one or more layers of the above-mentioned film, wherein the thickness of the film is 0.05 to 0.30 mm. Preferably, the sealing assembly 4 is made of PTFE film with a thickness of 0.15 to 0.18 mm by punching, and each sealing assembly includes two layers of film, which are fixed to the outlet of the reservoir 2 by compression screws.

[0027] The electrolyte buffer device 5 is equipped with an electrolyte injection branch pipe 7, such as... Figure 2 As shown, the cross-section of the electrolyte channel is a circular hole or a flared hole, and the end face of the hole has a rounded or chamfered transition; the flow channel can be... Figure 2 The circular flow channel in (a) can also be Figure 2 (b) The funnel-shaped flow channel can also be Figure 2 (c) The electrolyte flow channels with different orientations can be adjusted according to the electrolyte flow direction; the orifice diameter and number of electrolyte channels are determined based on the cross-sectional area of ​​the buffer device. The electrolyte injection branch pipes 7 of a single cell can be grouped, with each group having a different orifice diameter and different fluid resistance within the branch pipes; for example... Figure 3 As shown, the number of groups is determined based on the number of individual cell pairs in the battery pack. Each group contains 3 to 5 individual cells. The fluid resistance of the branch pipes within a group is the same. The resistance between the areas of the electrolyte injection branch pipe 7 should be h1 < h2 < h3 ... < hn (1, 2 ... n are group numbers, with the area below the reservoir outlet as the starting point for numbering). By grouping the electrolyte injection branch pipes 7, the resistance of each group of branch pipes can be adjusted according to specific needs. The flow direction of the electrolyte 3 in the individual cell 11 is as follows. Figure 4 As shown.

[0028] The electrolyte buffer device 5 can be made of non-metallic materials such as nylon, polyvinyl chloride, polytetrafluoroethylene, polyethylene, or polypropylene. Preferably, the electrolyte buffer device 5 is made of nylon 1010 material and has eight evenly distributed flared holes, with the flared holes facing vertically. The average equivalent cross-sectional area of ​​the flared holes is equal to the area of ​​the outlet of the reservoir 2. The distance between the upper end face of the buffer device 5 and the lower end face of the sealing component 4 is 6.5 mm.

[0029] The battery casing 6 contains 30 individual cell cavities, arranged in two rows, 15 cells on each side; each cell cavity corresponds to one electrolyte injection branch pipe. The 15 injection branch pipes are divided into 5 groups, with each group containing branch pipes of the same diameter: φ2.1mm, φ2.0mm, φ1.8mm, φ1.6mm, and φ1.4mm. After assembling these components, an electrolyte distribution simulation test was conducted. The test results are shown below. Figure 5 The average deviation of electrolyte injection volume in a single cell is 3.4%, and the deviation between the maximum and minimum injection volume is 13.2%. The uniformity of electrolyte distribution has been greatly improved, which can meet the electrolyte requirements of battery discharge.

[0030] The above embodiments are merely illustrative of the principles and effects of the present invention, as well as some of the application examples. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of the present invention, and these all fall within the protection scope of the present invention.

Claims

1. An electrolyte distribution system for a reserve battery, characterized in that: The device includes a reservoir (2) for holding electrolyte (3) and a gas generator (1) connected to the reservoir (2). The gas generator (1) consists of a gunpowder pack and an igniter. A sealing assembly (4) consisting of one or more layers of PTFE, PE, or PVC film with a thickness of 0.05 to 0.30 mm is provided at the bottom opening of the reservoir (2). The sealing assembly (4) is connected to a common flow channel (8) below through an electrolyte buffer device (5). The common flow channel (8), which is composed of a common flow channel cover plate (9) and a battery body shell (6), is connected to multiple liquid injection branch pipes (7) corresponding to individual cells (11). The liquid injection branch pipes (7) are connected according to the individual cells (11) 11) The numbers are grouped into groups, each containing 3 to 5 individual cells (11). The fluid resistance of the branch pipes (7) within the group is the same. The resistance between the regions of the injection branch pipes (7) is h1 < h2 < h3 ... < hn, where 1, 2 ... n are group numbers, with the number starting below the outlet of the reservoir (2). After the gunpowder in the gas generator (1) is detonated, high-pressure gas is generated, which acts on the electrolyte (3) and squeezes the sealing assembly (4). After the membrane of the sealing assembly (4) is broken, the electrolyte (3) enters the electrolyte buffer device (5) and fills the common flow channel (8). Then, it is injected into each individual cell (11) through the injection branch pipe (7) to complete the distribution of electrolyte (3).

2. The electrolyte distribution system for a reserve battery according to claim 1, characterized in that, The sealing assembly (4) uses two layers of PTFE membrane with a thickness of 0.15 to 0.18 mm, which are fixed to the outlet of the reservoir (2) by a compression screw.

3. The electrolyte distribution system for a reserve battery according to claim 1, characterized in that, The liquid reservoir (2) is made of stainless steel or titanium alloy by welding.

4. The electrolyte distribution system for a reserve battery according to claim 1, characterized in that, The electrolyte buffer device (5) is installed directly below the sealing assembly (4), and the distance between the upper end face and the lower end face of the sealing assembly (4) is ≥5mm.

5. An electrolyte distribution system for a storage battery according to claim 1, 2, 3, or 4, characterized in that, The injection branch pipe (7) is a circular cross-section hole, a trumpet hole, or a blood hole, and the end face of the hole has a rounded or chamfered transition.

6. The electrolyte distribution system for a reserve battery according to claim 5, characterized in that, The electrolyte buffer device (5) is made of nylon, polyvinyl chloride, polytetrafluoroethylene, polyethylene or polypropylene.

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