Pressure control mechanism for solid-state battery cycle expansion performance testing

Abstract

This utility model discloses a pressure control mechanism for testing the cyclic expansion performance of solid-state batteries, which can provide controllable and precise environmental parameter control for battery expansion detection. It includes an oil tank, a hydraulic cylinder, a drive device, and a static pressure container. The oil tank stores hydraulic oil. The hydraulic cylinder includes a cylinder body and a piston rod dynamically sealed within the cylinder body. The cylinder body has a first inlet and a first outlet, with the first inlet connected to the oil tank. The drive device is connected to the piston rod and drives the piston rod to reciprocate within the cylinder body to draw hydraulic oil into the first inlet and pump it out of the first outlet. The static pressure container includes a sealed container shell and a battery detection probe and a pressure gauge mounted thereon. The container shell holds the battery under test and has a second inlet and a second outlet whose opening and closing states are controllable. The second inlet connects to the first outlet, and the second outlet connects to the oil tank. The inner and outer ends of the battery detection probe are respectively connected to the tabs of the battery under test and a charge / discharge meter.

Description

Technical Field

[0001] This utility model belongs to the field of battery expansion detection technology, and specifically refers to a pressure control mechanism for testing the cyclic expansion performance of solid-state batteries. Background Technology

[0002] In existing technologies, some batteries, such as lithium-ion batteries, expand to a certain extent during charging and discharging due to changes in their internal active materials. This expansion exerts a certain expansion force on the battery casing, causing changes in its thickness. In existing technologies, as the compaction density of battery materials increases, their expansion rate also increases, leading to significant thickness changes after a certain period of use. This negatively impacts battery life and the parallel assembly of multiple batteries. Therefore, to optimize battery module design, it is necessary to continuously charge and discharge the battery to monitor its expansion data throughout its entire lifespan.

[0003] Currently, battery expansion detection typically involves using a pressure plate with a pressure sensor in the equipment or tooling to press the battery onto a support plate, then powering on the battery and reading the changes in the pressure sensor values ​​to detect expansion. When experiments require high precision, this detection method is no longer sufficient because: (1) Batteries are usually flat, and when they expand, they exert expansion force on a large area of ​​the pressure plate, while the pressure sensor and the pressure plate are connected at a single point with a small contact area, so the expansion force of the battery cannot be accurately fed back to the pressure sensor; (2) The battery and the pressure sensor are separated by the pressure plate, which is usually made of hard material, so some of the expansion force is dissipated by the pressure plate during the expansion process, resulting in errors; (3) The detection function is limited. Specifically, this method can only detect changes in expansion force under charging and discharging conditions, and cannot be used to detect changes in battery parameters under different conditions such as constant pressure, holding pressure, and variable pressure. Utility Model Content

[0004] The main purpose of this invention is to provide a pressure control mechanism for testing the cyclic expansion performance of solid-state batteries, which solves the problems existing in the prior art. It can provide controllable and accurate environmental parameter control for battery expansion detection, and finally obtain more accurate test results. It has good adaptability and flexibility.

[0005] To achieve the above objectives, the solution of this utility model is: A pressure control mechanism for testing the cyclic expansion performance of solid-state batteries includes an oil reservoir, at least one set of hydraulic cylinders, a drive device, and a hydrostatic container. The oil reservoir stores hydraulic oil. Each hydraulic cylinder includes a cylinder body and a piston rod dynamically sealed within the cylinder body. The cylinder body has a first inlet and a first outlet, with the first inlet communicating with the oil reservoir. The drive device is kinetically connected to the piston rod and drives the piston rod to reciprocate within the cylinder body at a preset frequency and stroke, thereby drawing hydraulic oil into the first inlet and pumping it out of the first outlet. The hydrostatic container includes a sealed container shell and a battery detection probe and a pressure gauge mounted on the container shell. The container shell houses the battery under test and has a second inlet and a second outlet with controllable opening and closing states. The second inlet communicates with the first outlet, and the second outlet communicates with the oil reservoir. The inner end of the battery detection probe connects to the tab of the battery under test, and its outer end connects to a charge / discharge instrument. The pressure gauge detects the liquid pressure within the container shell.

[0006] A first solenoid valve and a first flow meter are provided between the first outlet and the second inlet. The first solenoid valve is used to control the opening and closing of the pipeline between the first outlet and the second inlet, and the first flow meter is used to detect the flow rate of hydraulic oil flowing into the static pressure vessel.

[0007] A second solenoid valve and a second flow meter are provided between the second outlet and the oil storage tank. The second solenoid valve is used to control the opening and closing of the pipeline between the second outlet and the oil storage tank, and the second flow meter is used to detect the flow rate of hydraulic oil discharged from the static pressure vessel.

[0008] The oil storage tank is equipped with an exhaust valve and a return oil pump; the return oil pump is connected to the second outlet.

[0009] The static pressure vessel also includes at least one heating rod disposed on the vessel shell.

[0010] The static pressure vessel also includes a pressure relief valve located on the top of the vessel shell.

[0011] The second inlet is located on the side of the container shell and near its bottom, and the second outlet is located on the top surface of the container shell.

[0012] The driving device is a servo motor, which is connected to the piston rod via a lead screw drive.

[0013] The container shell includes a sealed body and a cover; the battery detection probe and pressure gauge are both mounted on the cover; a pair of pull rods are vertically connected to both ends of the lower surface of the cover, a support plate is connected between the lower ends of the pull rods, and a fixing clamp can be installed between the two ends of each pull rod; the support plate is used to support the lower surface of the battery under test, and the fixing clamp is used to clamp and fix the upper surface or side of the battery under test.

[0014] After adopting the above technical solution, the present invention has the following technical effects: This invention uses a drive device to drive a piston rod, which pumps hydraulic oil from the reservoir into a static pressure vessel according to a preset frequency and stroke. By adjusting the number of piston rod movements and the stroke range, a certain amount of hydraulic oil can be precisely pumped in, thus controlling the hydraulic pressure within the static pressure vessel. During battery testing, the battery under test is fully immersed in the hydraulic oil, making comprehensive and seamless contact with it. The expansion force generated by the battery's expansion is directly reflected in the change in hydraulic pressure, which can then be accurately detected by a pressure gauge, thereby improving testing accuracy. When other types of testing require constant pressure or variable pressure modes, the second inlet and outlet can be flexibly opened and closed to perform pressurization and depressurization operations, flexibly controlling the internal hydraulic pressure changes of the static pressure vessel to meet various testing needs. Attached Figure Description

[0015] Figure 1 This is a structural block diagram of a specific embodiment of the present utility model.

[0016] Figure 2 The overall three-dimensional representation of a specific embodiment of this utility model Figure 1 .

[0017] Figure 3 The overall three-dimensional representation of a specific embodiment of this utility model Figure 2 .

[0018] Figure 4 This is an overall front view of a specific embodiment of the present utility model.

[0019] Figure 5 This is an overall side view of a specific embodiment of the present utility model.

[0020] Figure 6 This is an overall top view of a specific embodiment of the present utility model.

[0021] Figure 7 This is an exploded view of the static pressure vessel according to a specific embodiment of the present invention.

[0022] Explanation of icon numbers: 1-Oil reservoir; 2-Hydraulic cylinder; 21-Cylinder body; 211-First inlet; 212-First outlet; 22-Piston rod; 3-Drive device; 4-Hydraulic pressure vessel; 41-Container shell; 41a-Body; 41b-Cover; 411-Second inlet; 412-Second outlet; 42-Battery detection probe; 43-Pressure gauge; 44-Heating rod; 45-Pressure relief valve; 46-Pull rod; 47-Support plate; 48-Fixing clamp; 5-Charge / discharge instrument; 6-First solenoid valve; 7-First flow meter; 8-Second solenoid valve; 9-Second flow meter; 10-Exhaust valve; 20-Return oil pump; 30-Frame; a-Battery under test; b-Taper. Detailed Implementation

[0023] To further explain the technical solution of this utility model, the following detailed description is provided through specific embodiments.

[0024] refer to Figures 1 to 7 As shown, this utility model discloses a pressure control mechanism for testing the cyclic expansion performance of solid-state batteries, including an oil tank 1, and at least one set of hydraulic cylinders 2, a drive device 3, and a static pressure container 4. Oil reservoir 1 is used to store hydraulic oil; The hydraulic cylinder 2 includes a cylinder body 21 and a piston rod 22 that is dynamically sealed within the cylinder body 21; the cylinder body 21 is provided with a first inlet 211 and a first outlet 212, and the first inlet 211 is connected to the oil reservoir 1; The drive unit 3 is connected to the piston rod 22 for driving the piston rod 22 to reciprocate within the cylinder 21 according to a preset frequency and stroke, so as to draw hydraulic oil into the first inlet 211 and pump it out of the first outlet 212. The static pressure vessel 4 includes a sealed container shell 41, and a battery detection probe 42 and a pressure gauge 43 mounted on the container shell 41. The container shell 41 is used to house the battery to be tested a and is provided with a second inlet 411 and a second outlet 412 whose opening and closing states can be controlled. The second inlet 411 is connected to the first outlet 212, and the second outlet 412 is connected to the oil tank 1. The inner end of the battery detection probe 42 is used to connect to the tab b of the battery to be tested a, and its outer end is used to connect to the charge / discharge instrument 5, so as to realize the charging and discharging of the battery a and detect its relevant parameters (such as voltage, current, etc.). The pressure gauge 43 is used to detect the liquid pressure inside the container shell 41.

[0025] Through the above scheme, this utility model drives the piston rod 22 via the drive device 3, which can pump the hydraulic oil in the oil tank 1 into the static pressure container 4 according to a preset frequency and stroke. By adjusting the number of strokes and the stroke range of the piston rod 22, a certain amount of hydraulic oil can be precisely pumped in, thereby controlling the hydraulic pressure inside the static pressure container 4. During the battery testing process, the battery under test a is fully immersed in the hydraulic oil, making all-round and no dead angle contact with the hydraulic oil. The expansion force generated by its expansion can also be directly reflected as a change in hydraulic pressure, which can be accurately detected by the pressure gauge 43, thereby improving the testing accuracy. When other types of testing are required and constant pressure, variable pressure, or other modes are needed, pressurization and depressurization operations can be performed by flexibly opening and closing the second inlet 411 and the second outlet 412, flexibly controlling the internal hydraulic pressure changes of the static pressure container 4 to meet various testing needs.

[0026] The following are specific embodiments of the present invention.

[0027] A first solenoid valve 6 and a first flow meter 7 are provided between the first outlet 212 and the second inlet 411. The first solenoid valve 6 is used to control the opening and closing of the pipeline between the first outlet 212 and the second inlet 411, that is, to control the opening and closing of the second inlet 411. The first flow meter 7 can detect the flow rate of hydraulic oil flowing into the static pressure vessel 4.

[0028] A second solenoid valve 8 and a second flow meter 9 are provided between the second outlet 412 and the oil storage tank 1. The second solenoid valve 8 is used to control the opening and closing of the pipeline between the second outlet 412 and the oil storage tank 1, that is, to control the opening and closing of the second outlet 412. The second flow meter 9 can detect the flow rate of hydraulic oil discharged from the static pressure vessel 4.

[0029] The aforementioned oil storage tank 1 is equipped with an exhaust valve 10 and a return oil pump 20. When the exhaust valve 10 is opened, it can be used to discharge the gas in the oil storage tank 1 to ensure that the hydraulic oil can flow smoothly. The return oil pump 20 is connected to the second outlet 412 through a pipeline (the aforementioned second solenoid valve 8 and second flow meter 9 may also be installed between the two) to provide the power for the hydraulic oil to flow back to the oil storage tank 1.

[0030] The aforementioned hydrostatic vessel 4 also includes at least one heating rod 44 disposed on the vessel shell 41. The heating rod 44 is used to heat the hydraulic oil inside the vessel shell 41 to provide a temperature environment that meets the testing requirements. The heating rod 44 is preferably disposed at the bottom of the vessel shell 41.

[0031] The aforementioned static pressure vessel 4 also includes a pressure relief valve 45 disposed on the top of the vessel shell 41. When the internal pressure of the static pressure vessel 4 exceeds a preset value or other conditions require pressure relief, the pressure relief valve 45 can be automatically or manually opened to relieve pressure, depending on the type of pressure relief valve 45.

[0032] The second inlet 411 is located on the side of the container housing 41 near its bottom, and the second outlet 412 is located on the top surface of the container housing 41. Therefore, when oil is introduced into the hydrostatic container 4, the hydraulic oil flows from bottom to top, which can expel air from inside the container housing 21 and reduce interference factors in battery detection.

[0033] The aforementioned drive device 3 is a servo motor, which is connected to the piston rod 22 via a lead screw drive. By employing a servo motor, its high precision, high speed, and high reliability can be utilized to programmatically control the reciprocating motion of the piston rod 22 according to a preset frequency and stroke, thereby precisely controlling the pumping and discharging of hydraulic oil to meet the requirements of battery expansion detection.

[0034] The aforementioned container shell 41 includes a sealed body 41a and a cover 41b. The battery testing probe 42, pressure gauge 43, and pressure relief valve 45 are all mounted on the cover 41b. A pair of pull rods 46 are vertically connected to both ends of the lower surface of the cover 41b. A support plate 47 is connected between the lower ends of the pull rods 46, and a fixing clip 48 can be installed between the two ends of each pull rod 46 in a lifting manner. The support plate 47 supports the lower surface of the battery a under test, and the fixing clip 48 clamps and fixes the upper surface or side of the battery a under test, such as clamping it onto the thin film jacket of the battery a under test. This provides a limiting effect on the battery a under test, preventing it from violently shaking within the container shell 41 during testing. The contact surface between the body 41a and the cover 41b can be sealed using a sealing ring or similar method and locked with several bolts, ensuring the connection strength between the cover 41b and the body 41a and meeting the high-pressure requirements of the container body 41 during testing.

[0035] This utility model also includes a frame 30, with multiple static pressure vessels 4 arranged at equal intervals on the front side of the upper surface of the frame 30; multiple hydraulic cylinders 2 arranged at equal intervals on the rear side of the upper surface of the frame 30, and one to one opposite the static pressure vessels 4; the oil storage tank 1 and the drive device 3 are both installed inside the frame 30.

[0036] The above embodiments and figures are not intended to limit the product form and style of this utility model. Any appropriate changes or modifications made by those skilled in the art should be considered as not departing from the patent scope of this utility model.

Claims

1. A pressure control mechanism for testing the cyclic expansion performance of solid-state batteries, characterized in that: It includes an oil reservoir, as well as at least one set of hydraulic cylinders, a drive unit, and a hydrostatic container; The oil tank is used to store hydraulic oil; The hydraulic cylinder includes a cylinder body and a piston rod that is dynamically sealed within the cylinder body; the cylinder body is provided with a first inlet and a first outlet, and the first inlet is connected to the oil reservoir; The drive device is connected to the piston rod for driving the piston rod to reciprocate within the cylinder to draw hydraulic oil into the first inlet and pump it out of the first outlet. The hydrostatic container includes a sealed container shell, and a battery testing probe and a pressure gauge mounted on the container shell. The container shell is used to house the battery under test and is provided with a second inlet and a second outlet whose opening and closing states are controllable. The second inlet is connected to the first outlet, and the second outlet is connected to the oil tank. The inner end of the battery testing probe is used to connect to the tab of the battery under test, and its outer end is used to connect to a charge / discharge instrument. The pressure gauge is used to detect the liquid pressure inside the container shell.

2. The pressure control mechanism for solid-state battery cycle expansion performance testing as described in claim 1, characterized in that: A first solenoid valve and a first flow meter are provided between the first outlet and the second inlet. The first solenoid valve is used to control the opening and closing of the pipeline between the first outlet and the second inlet, and the first flow meter is used to detect the flow rate of hydraulic oil flowing into the static pressure vessel.

3. The pressure control mechanism for testing the cyclic expansion performance of solid-state batteries as described in claim 1, characterized in that: A second solenoid valve and a second flow meter are provided between the second outlet and the oil storage tank. The second solenoid valve is used to control the opening and closing of the pipeline between the second outlet and the oil storage tank, and the second flow meter is used to detect the flow rate of hydraulic oil discharged from the static pressure vessel.

4. The pressure control mechanism for solid-state battery cycle expansion performance testing as described in claim 1, characterized in that: The oil storage tank is equipped with an exhaust valve and a return oil pump; the return oil pump is connected to the second outlet.

5. The pressure control mechanism for solid-state battery cycle expansion performance testing as described in claim 1, characterized in that: The static pressure vessel also includes at least one heating rod disposed on the vessel shell.

6. The pressure control mechanism for testing the cyclic expansion performance of solid-state batteries as described in claim 1, characterized in that: The static pressure vessel also includes a pressure relief valve located on the top of the vessel shell.

7. The pressure control mechanism for testing the cyclic expansion performance of solid-state batteries as described in claim 1, characterized in that: The second inlet is located on the side of the container shell and near its bottom, and the second outlet is located on the top surface of the container shell.

8. The pressure control mechanism for testing the cyclic expansion performance of solid-state batteries as described in claim 1, characterized in that: The driving device is a servo motor, which is connected to the piston rod via a lead screw drive.

9. The pressure control mechanism for testing the cyclic expansion performance of solid-state batteries as described in claim 1, characterized in that: The container shell includes a sealed body and a cover; the battery detection probe and pressure gauge are both mounted on the cover; a pair of pull rods are vertically connected to both ends of the lower surface of the cover, a support plate is connected between the lower ends of the pull rods, and a fixing clamp can be installed between the two ends of each pull rod; the support plate is used to support the lower surface of the battery under test, and the fixing clamp is used to clamp and fix the upper surface or side of the battery under test.

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