A device for rapid measurement of pouch cell volume in the laboratory

Abstract

This utility model relates to the field of battery testing technology and provides a device for rapidly measuring the volume of a pouch battery in a laboratory. The device includes a basket, a constant-temperature ultrasonic water bath, and an electronic balance. The basket comprises a frame for holding the test battery, which is located inside the constant-temperature ultrasonic water bath. The constant-temperature ultrasonic water bath contains a buoyancy medium that submerges the basket. The constant-temperature ultrasonic water bath is placed on the electronic balance. Based on Archimedes' principle of buoyancy, this device calculates the battery volume by measuring the ratio of mass to the buoyancy medium, providing better accuracy than the conventional method of observing volume changes through water displacement.

Description

Technical Field

[0001] This utility model relates to the field of battery testing technology, and more specifically, to a device for rapidly measuring the volume of a pouch battery in a laboratory. Background Technology

[0002] Currently, lithium-ion battery volume measurement mainly relies on the following technologies:

[0003] 1. Drainage method: The volume is calculated by measuring the change in water level before and after the battery is submerged, but it requires wrapping the battery with a waterproof membrane, which is cumbersome and prone to errors due to air bubbles.

[0004] 2. Automated liquid level monitoring device: such as patent CN215811075U, which uses a water pressure sensor to monitor the liquid level, but it relies on a riser pipe with a fixed inner diameter, and the accuracy of the test liquid (water) is easily affected by surface tension.

[0005] 3. Measurement of porous box: The drainage volume is indirectly calculated by electronic scale, but the device has a complex structure and poor adaptability to battery shape.

[0006] The above technology has the following problems:

[0007] 1. Liquid selection (such as water) is easily affected by temperature and air bubbles, resulting in significant errors;

[0008] 2. Insufficient control over the levitation attitude of the pouch battery affects measurement repeatability.

[0009] 3. Because the packaging material of pouch batteries is soft and easily deformed, traditional geometric measurement methods have large errors (more than ±5%).

[0010] 4. When using water or ethanol in the conventional drainage method, the liquid can easily seep into the battery, causing short circuits or corrosion. Problems such as air bubble adhesion and liquid evaporation affect measurement accuracy.

[0011] In view of this, this utility model is proposed. Utility Model Content

[0012] The purpose of this invention is to provide a device for rapidly measuring the volume of pouch batteries in a laboratory, which aims to improve at least one of the problems pointed out in the background art.

[0013] The embodiments of this utility model can be implemented as follows:

[0014] In the first aspect, this utility model provides a device for rapidly measuring the volume of a soft-pack battery in the laboratory, including a basket, a constant temperature ultrasonic water bath, and an electronic balance;

[0015] The basket includes a basket for placing the test battery. The basket is located inside the constant temperature ultrasonic water bath, which contains a buoyancy medium that submerges the basket. The constant temperature ultrasonic water bath is placed on the electronic balance.

[0016] In an optional embodiment, the buoyancy medium is dimethyl silicone oil.

[0017] In an optional embodiment, the basket has mesh openings that facilitate the flow of the buoyancy medium, the diameter of which is ≤2mm.

[0018] In an optional embodiment, the basket is a PP basket or a PE basket.

[0019] In an optional embodiment, the device further includes a support frame, the support frame including a cantilever, the basket including the basket body and a connector, one end of the connector being connected to the basket body and the other end being connected to the cantilever.

[0020] In an optional embodiment, the support includes the cantilever and the vertical rod, the cantilever and the vertical rod being perpendicular to each other, and the cantilever and the vertical rod being connected by an adjustable connecting mechanism;

[0021] The adjustable connection mechanism includes a connecting body and a first fastening bolt and a second fastening bolt;

[0022] The connector is provided with a first mounting groove for the cantilever to pass through and a second mounting groove for the vertical rod to pass through;

[0023] The connector is provided with a first screw hole for the first fastening bolt to pass through and communicating with the first mounting groove, and a second screw hole for the second fastening bolt to pass through and communicating with the second mounting groove.

[0024] The first fastening bolt is used to fasten the cantilever into the first mounting groove by passing through the first screw hole, and the second fastening bolt is used to fasten the cantilever into the second mounting groove by passing through the second screw hole.

[0025] In an optional embodiment, the connector is a plurality of suspending wires, one end of each suspending wire being connected to the basket and the other end being connected to the cantilever.

[0026] In an optional embodiment, the device further includes a base, the bracket is connected to the base, and the electronic balance is placed on the base.

[0027] In an optional implementation, the electronic balance is a high-precision electronic balance with a resolution of 0.1 mg.

[0028] The beneficial effects provided by the embodiments of this utility model include:

[0029] The device provided in this embodiment controls the test process to maintain a constant temperature, eliminating the influence of ambient temperature on buoyancy calculation. It also eliminates the influence of air bubbles in the medium on the test results through ultrasound. Based on Archimedes' principle of buoyancy, the battery volume is calculated by measuring the ratio of mass to buoyancy medium. Compared with the conventional method of observing volume changes by displacement, the volume measurement is more accurate. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the apparatus for rapidly measuring the volume of a pouch battery in the laboratory provided in this embodiment;

[0032] Figure 2 This is a top view of the adjustable connecting mechanism assembled with the vertical rod and cantilever.

[0033] Icons: 100 - Device for quickly measuring the volume of a pouch battery; 110 - Basket; 111 - Connector; 112 - Basket body; 120 - Constant temperature ultrasonic water bath; 130 - Electronic balance; 140 - Buoyancy medium; 150 - Bracket; 151 - Cantilever; 152 - Vertical rod; 160 - Base; 180 - Adjustable connection mechanism; 181 - First mounting slot; 182 - Second mounting slot; 183 - First fastening bolt; 184 - Second fastening bolt; 185 - Connector; 186 - First screw hole; 187 - Second screw hole; 2 - Pouch battery. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0035] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0036] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0037] In the description of this utility model, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed during use, they are only for the convenience of describing this utility model 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, and therefore should not be construed as a limitation of this utility model.

[0038] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0039] It should be noted that, where there is no conflict, the features in the embodiments of this utility model can be combined with each other.

[0040] like Figure 1 and Figure 2 As shown, this utility model embodiment provides a device 100 for rapid laboratory measurement of the volume of a soft-pack battery, including a basket 110, a constant temperature ultrasonic water bath 120, and an electronic balance 130.

[0041] The basket 110 includes a basket 112 for placing test batteries. The basket 112 is located inside a constant temperature ultrasonic water bath 120. The constant temperature ultrasonic water bath 120 contains a buoyancy medium 140, which submerges the basket 112. The constant temperature ultrasonic water bath 120 is placed on an electronic balance 130.

[0042] The corresponding test method for this device is as follows:

[0043] Step (1): Volume measurement

[0044] 1. Set up the device.

[0045] 2. Immerse the basket 110 in the buoyancy medium 140, eliminate air bubbles by using the ultrasonic function of the constant temperature ultrasonic water bath, and then operate the electronic balance 130 to weigh the container, basket 110 and dimethyl silicone oil.

[0046] 3. Place the battery in the basket 110 to completely submerge it, turn on the ultrasonic cleaner to eliminate air bubbles, and measure the apparent mass (i.e. the mass reflected by the electronic balance 130) m.

[0047] 3. Calculate the battery volume Vbattery:

[0048] V 电池 =m / ρ 介质 .

[0049] During the measurement, the battery was suspended in the liquid. 电池 g = F 浮 +F 支撑 The supporting force (F) on the solution (buoyancy medium) in the water bath. 支 ) equals the buoyancy reaction force (F) 浮反 ) and solution gravity (m 溶液 The sum of g), because F 支 =m 天 g is the product of the reading displayed by the electronic balance and the gravitational coefficient, so m 天 g = F 浮反 +m 溶液 g, after zeroing the balance before the test, yields m. 天 g = F 浮反 According to Archimedes' principle of buoyancy, F 浮反 =ρ 介质 V 排 g, therefore ρ 介质 V 排 g = m 天 g, In conclusion, V 电池 =m 天 / ρ medium.

[0050] Step 2: Error Correction

[0051] The liquid density and environmental fluctuations are calibrated using standard volume blocks (such as glass spheres of known volume).

[0052] The device provided in this embodiment controls the test process to maintain a constant temperature, eliminating the influence of ambient temperature on buoyancy calculation. It also eliminates the influence of air bubbles in the medium on the test results through ultrasound. Based on Archimedes' principle of buoyancy, the battery volume is calculated by measuring the ratio of the mass to the buoyancy medium (140). Compared with the conventional method of observing volume changes by displacement, the volume measurement is more accurate.

[0053] Specifically, the constant temperature ultrasonic water bath has an ultrasonic transducer built in. When removing air bubbles, the ultrasonic transducer is turned on (frequency 40kHz, time 10s) to eliminate the air bubbles.

[0054] Optionally, the buoyancy medium 140 is dimethyl silicone oil.

[0055] Dimethyl silicone oil possesses chemical inertness, low volatility, and insulating properties. Its low volatility and high density (0.965 g / cm³) contribute to its superior performance. 3 This can reduce bubble adhesion and improve measurement stability.

[0056] Optionally, the basket 112 has mesh openings that facilitate the flow of the buoyancy medium 140, with the mesh opening diameter ≤ 2 mm.

[0057] Optionally, the basket 112 is a PP basket 112 or a PE basket 112.

[0058] Optionally, the device further includes a support 150, which includes a cantilever 151. The basket 110 includes a basket body 112 and a connector 111, with one end of the connector 111 connected to the basket body 112 and the other end connected to the cantilever 151.

[0059] Optionally, the bracket 150 includes a cantilever 151 and a vertical rod 152, the cantilever 151 and the vertical rod 152 are perpendicular to each other, and the cantilever 151 and the vertical rod 152 are connected by an adjustable connecting mechanism 180.

[0060] The adjustable connection mechanism 180 includes a connector 185 and a first fastening bolt 183 and a second fastening bolt 184;

[0061] The connector 185 is provided with a first mounting groove 181 for the cantilever 151 to pass through and a second mounting groove 182 for the vertical rod 152 to pass through;

[0062] The connector 185 is provided with a first screw hole 186 for the first fastening bolt 183 to pass through and communicate with the first mounting groove 181, and a second screw hole 187 for the second fastening bolt 184 to pass through and communicate with the second mounting groove 182.

[0063] The first fastening bolt 183 is used to fasten the cantilever 151 into the first mounting groove 181 by passing through the first screw hole 186, and the second fastening bolt 184 is used to fasten the cantilever 151 into the second mounting groove 182 by passing through the second screw hole 187.

[0064] During the experiment, the vertical rod 152 is inserted into the second mounting groove 182, the sliding connector 185 is slid to a suitable height, the second fastening bolt 184 is passed through the second screw hole 187, and the second fastening bolt 184 is pressed against the vertical rod 152; the cantilever 151 with the basket 110 is inserted into the first mounting groove 181, the angle and extension length of the cantilever 151 are adjusted, the first fastening bolt 183 is passed through the first screw hole 186, and the first fastening bolt 183 is pressed against the cantilever 151, thus completing the installation of the cantilever 151 and ensuring that the basket 112 is at a suitable height.

[0065] The specific configuration of the adjustable connecting mechanism 180, cantilever 151, and vertical rod 152 enables the horizontal length and angle of cantilever 151 to be adjusted, and the vertical height and angle of cantilever 151 to be adjusted, thereby ensuring that the basket 110 connected to the connector 111 can be vertically suspended in the constant temperature and humidity water bath, thereby ensuring that the tested soft-pack battery 2 is vertically suspended, and thus ensuring the accuracy of the test results.

[0066] The connector 111 consists of multiple suspension wires, with one end of each wire connected to the basket 112 and the other end connected to the cantilever 151.

[0067] Optionally, the device also includes a base 160, a bracket 150 connected to the base 160, and an electronic balance 130 placed on the base 160.

[0068] Optionally, to improve the accuracy of the test results, the electronic balance 130 is a high-precision electronic balance 130 with a resolution of 0.1 mg.

[0069] In summary, the device provided by this utility model embodiment has the following advantages:

[0070] 1. Based on Archimedes' principle of buoyancy, the battery volume is calculated by the ratio of mass to 140 of the buoyant medium. This method is more accurate than the conventional method of observing volume changes by displacement.

[0071] 2. Maintaining a constant temperature during the testing process and eliminating the influence of ambient temperature on buoyancy calculations can further improve the accuracy of test results.

[0072] 3. By using ultrasound to eliminate the influence of air bubbles in the medium on the test results, the accuracy can be significantly improved.

[0073] 4. In a preferred embodiment, dimethyl silicone oil is used as the buoyancy medium 140 instead of conventional water or ethanol, possessing both chemical inertness, low volatility, and insulating properties. Its low volatility and high density (0.965 g / cm³) are advantageous. 3 This can reduce bubble adhesion and improve measurement stability.

[0074] 5. The adjustable connection mechanism is set at 180 degrees to ensure that the battery is completely submerged and in a vertical position, with a repeatability error of ≤ ±0.2%.

[0075] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model.

Claims

1. A device for rapidly measuring the volume of a pouch battery in a laboratory, characterized by, Includes a suspended platform, a constant-temperature ultrasonic water bath, and an electronic balance; The basket includes a basket for placing the test battery. The basket is located inside the constant temperature ultrasonic water bath, which contains a buoyancy medium that submerges the basket. The constant temperature ultrasonic water bath is placed on the electronic balance.

2. The apparatus of claim 1, wherein, The buoyancy medium is dimethyl silicone oil.

3. The apparatus of claim 1, wherein, The basket has mesh openings that facilitate the flow of the buoyancy medium, and the diameter of the mesh openings is ≤2mm.

4. The apparatus of claim 1, wherein, The basket is a PP basket or a PE basket.

5. The apparatus of claim 1, wherein, The device also includes a support frame, which includes a cantilever. The basket includes the basket body and a connector, one end of which is connected to the basket body and the other end of which is connected to the cantilever.

6. The apparatus of claim 5, wherein, The bracket includes the cantilever and the vertical rod, the cantilever and the vertical rod are perpendicular to each other, and the cantilever and the vertical rod are connected by an adjustable connecting mechanism; The adjustable connection mechanism includes a connecting body and a first fastening bolt and a second fastening bolt; The connector is provided with a first mounting groove for the cantilever to pass through and a second mounting groove for the vertical rod to pass through; The connector is provided with a first screw hole for the first fastening bolt to pass through and communicating with the first mounting groove, and a second screw hole for the second fastening bolt to pass through and communicating with the second mounting groove. The first fastening bolt is used to fasten the cantilever into the first mounting groove by passing through the first screw hole, and the second fastening bolt is used to fasten the cantilever into the second mounting groove by passing through the second screw hole.

7. The apparatus of claim 6, wherein, The connector consists of multiple suspension wires, with one end of each wire connected to the basket and the other end connected to the cantilever.

8. The apparatus of claim 6, wherein, The device also includes a base, the bracket is connected to the base, and the electronic balance is placed on the base.

9. The apparatus of claim 1, wherein, The electronic balance is a high-precision electronic balance with a resolution of 0.1 mg.

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