CN116164869A - Method for uniformly applying initial pretightening force to battery cell - Google Patents
Method for uniformly applying initial pretightening force to battery cell Download PDFInfo
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- CN116164869A CN116164869A CN202310151335.2A CN202310151335A CN116164869A CN 116164869 A CN116164869 A CN 116164869A CN 202310151335 A CN202310151335 A CN 202310151335A CN 116164869 A CN116164869 A CN 116164869A
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- pressure sensor
- film type
- type pressure
- battery cell
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
- G01L5/0028—Force sensors associated with force applying means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L25/00—Testing or calibrating of apparatus for measuring force, torque, work, mechanical power, or mechanical efficiency
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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Abstract
The invention discloses a method for uniformly applying initial pretightening force to a battery cell, which comprises a bottom plate, a plurality of guide posts vertically connected to the bottom plate, a pressing plate sleeved on the guide posts in a lifting manner, a fastening piece arranged above the pressing plate and in threaded connection with the guide posts, and a pressurizing device arranged above the pressing plate, wherein the pressing plate is provided with a plurality of guide posts; and comprises the steps of: placing the film type pressure sensor and the battery cell to be tested in a center position between the pressing plate and the bottom plate in a lamination mode; the pressurizing device is used for applying pressure required by an experiment to the pressing plate, wherein the pressure value is N, the pressure value is M, and the fastening piece is locked; calibrating the film type pressure sensor on software to enable the display value of the film type pressure sensor to be N; and removing the pressurizing device, and performing fine adjustment on each fastener according to the distribution condition of the force on the film type pressure sensor, so that the pressure values of all the positions on the film type pressure sensor are equal, and the pressure values of all the positions are M. The invention can apply uniform and accurate initial pretightening force to the battery cell to be tested, and meets the requirement of specific experiments.
Description
Technical Field
The invention relates to the technical field of battery safety detection, in particular to a method for uniformly applying initial pretightening force to a battery cell.
Background
At present, new energy automobiles are in a strong development period, a power battery serving as a power source of the new energy automobiles is always an important research object in the field of the new energy automobiles, and consumer batteries are also continuously improving energy density. In the charge and discharge process of the battery cell, the battery cell can expand and contract along with the intercalation and deintercalation of lithium ions in the negative electrode. The expansion performance of the battery cell is evaluated by using two parameters, namely expansion force and expansion thickness, and most companies adopt a common bolt or guide post type three-piece steel clamp to carry out cyclic expansion force test. Particularly, the module battery has initial pretightening force design requirements on a single battery cell, so that the expansion behavior of the battery cell under a certain initial pretightening force can be accurately and effectively evaluated, the installation design of a battery cell module can be effectively guided, and the space utilization rate of the module can be improved on the premise of ensuring safety.
Referring to fig. 1, patent CN214426874U discloses a "battery cell cyclic expansion force testing fixture", which comprises a bottom plate 1 'for holding a battery cell 8' to be tested, a plurality of guide posts 3 'connected to the bottom plate 1', and a top plate 2 arranged opposite to the bottom plate 1 'and slidably arranged on the guide posts 3'; the cell cyclic expansion force testing tool further comprises a plurality of sleeve assemblies 6 'respectively sleeved on the guide posts 3', a plurality of fastening assemblies 4 'respectively screwed on the tops of the guide posts 3', a gasket 5 'arranged between the fastening assemblies 4' and the top plate 2', and a gasket 7' arranged on the top of the bottom supporting plate 1 'and/or the bottom of the top plate 2'. Wherein the sleeve assembly 6' comprises a telescopically engaged lower sleeve 601' and upper sleeve 602'; the fastening component 4 'is a nut screwed on the guide post 3'. In the practical use process of the tool, the following problems exist:
(1) when an initial pre-tightening force is applied to the battery cell, the top plate 2 'needs to be pressurized by using a pressurizing device, the four nuts are locked in a pressurized state and then withdrawn from the pressurizing device, and the connection part (namely threads) between the nuts and the guide post 3' can deform and release force in the withdrawal process, so that the actual initial pre-tightening force applied to the battery cell after the nuts are locked cannot be determined;
(2) in the nut locking process, the locking degrees of the four nuts are different, and the force applied to the surface of the battery cell cannot be uniformly distributed.
Disclosure of Invention
The invention aims to provide a method for uniformly applying initial pre-tightening force to a battery cell, which can apply uniform and accurate-value initial pre-tightening force to the battery cell to be tested and meet the requirements of specific experiments.
In order to achieve the above object, the solution of the present invention is:
the method for uniformly applying the initial pretightening force to the battery cell comprises a bottom plate, a plurality of guide posts vertically connected to the bottom plate, a pressing plate sleeved on the guide posts in a lifting manner, a fastening piece arranged above the pressing plate and in threaded connection with the guide posts, and a pressurizing device arranged above the pressing plate; and comprises the following steps:
step one, placing a film type pressure sensor and a cell to be tested in a center position between the pressing plate and the bottom plate in a lamination mode;
step two, applying pressure required by an experiment to the pressing plate through the pressurizing device, wherein the pressure value is N, the pressure value is M, and the fastening piece is locked;
step three, calibrating the film type pressure sensor on the software to enable the total display number of the film type pressure sensor to be N;
and step four, removing the pressurizing device, and performing fine adjustment on each fastener according to the distribution condition of the force on the film type pressure sensor, so that the pressure values of all the positions on the film type pressure sensor are equal and the pressure values of all the positions are M.
In the first step, the film type pressure sensor is placed on the bottom plate, and then the battery cell to be tested is placed on the film type pressure sensor; or, firstly placing the to-be-tested battery cell on the bottom plate, and then covering the film type pressure sensor on the to-be-tested battery cell.
Preferably, the number of the film type pressure sensors is multiple, and the film type pressure sensors are arranged on the upper surface of the base plate or the to-be-tested battery cell in an array mode.
The film type pressure sensor is a piezoelectric film type pressure sensor or a piezoresistance type packet mode pressure sensor.
The area of the film type pressure sensor is larger than the areas of the upper surface and the lower surface of the battery cell to be measured.
And a lead of the film type pressure sensor is led out from an uncovered part of the battery cell to be tested, and a pressure signal is transmitted to a pressure detection instrument through the lead.
The periphery of the guide post is provided with threads, and the fastening piece is a nut.
The pressurizing device is a pressurizing device with pressure display.
The battery cell to be tested is a rectangular soft package or square shell battery.
After the technical scheme is adopted, the invention has the following technical effects:
(1) the thin film pressure sensor is calibrated on software, so that the display of the thin film pressure sensor is truly and credible, and the problem of numerical drift of a pressure film is solved;
(2) the method can acquire the initial pretightening force value of the detection tool after the pressurizing device is removed, and improve the problem that the real pretightening force is unknown after the pressurizing device is locked;
(3) the problem of uneven pressure on the surface of the battery cell to be tested caused by different locking degrees due to separate locking of the fasteners can be solved, and the initial force distribution on the surface of the battery cell to be tested is obtained through the calibrated film type pressure sensor, so that the uniformity of the initial pretightening force on the surface of the battery cell to be tested is ensured by fine tuning of each fastener;
(4) the method is simple to use, can be directly used on the traditional detection tool, and does not need to improve the original detection tool.
Drawings
Fig. 1 is a schematic structural diagram of CN 214426874U;
FIG. 2 is a schematic diagram of an embodiment of the present invention;
reference numerals illustrate:
1- - -a bottom plate; 2- - -a guide post; 3- - -a pressing plate; 4- - -a fastener; 5- -a pressurizing device; 6- -a thin film pressure sensor; 7- -the cell to be tested.
Description of the embodiments
In order to further explain the technical scheme of the invention, the invention is explained in detail by specific examples.
For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments of the present invention. The components of the embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Accordingly, the following detailed description of the embodiments of the invention, as presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.
In the description of the embodiments of the present invention, it should be understood that the indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship conventionally put in place when the inventive product is used, or the orientation or positional relationship conventionally understood by those skilled in the art, is merely for convenience in describing the embodiments of the present invention, and is not intended to indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.
In the description of the embodiments of the present invention, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically connected, electrically connected or can be communicated with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
In the present invention, unless expressly stated or limited otherwise, a first feature "above" or "below" a second feature may include both the first and second features being in direct contact, as well as the first and second features not being in direct contact but being in contact with each other through additional features therebetween. Moreover, a first feature being "above," "over" and "on" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature is higher in level than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly under and obliquely below the second feature, or simply means that the first feature is less level than the second feature.
The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. In order to simplify the present disclosure, components and arrangements of specific examples are described below. They are, of course, merely examples and are not intended to limit the invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, which are for the purpose of brevity and clarity, and which do not themselves indicate the relationship between the various embodiments and/or arrangements discussed.
In addition, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the application of other processes and/or the use of other materials.
Referring to fig. 2, the conventional expansion detecting structure includes a base plate 1, a plurality of guide posts 2 vertically connected to the base plate 1, a pressing plate 3 liftably sleeved on the guide posts 2, a fastening member 4 disposed above the pressing plate 3 and screwed with the guide posts 2, and a pressurizing device 5 disposed above the pressing plate 3; the invention discloses a method for uniformly applying initial pretightening force to a battery cell, which comprises the following steps:
step one, placing a film type pressure sensor 6 and a cell 7 to be tested in a center position between a pressing plate 3 and a bottom plate 1 in a lamination mode;
step two, applying pressure (namely initial pretightening force) required by an experiment to the pressing plate 3 through the pressurizing device 5, wherein the pressure value is N, the pressure value is M, and locking the fastening piece 4;
step three, calibrating the film type pressure sensor 6 on software of the film type pressure sensor 6 to enable the total display number to be N;
and step four, removing the pressurizing device 5, and finely adjusting each fastener 4 according to the distribution condition of the force on the film type pressure sensor 6, so that the pressure values of all the positions on the film type pressure sensor 6 are equal and the pressure values of all the positions are M, and further, uniform initial pretightening force is applied to the surface of the battery cell 7 to be tested.
Specific embodiments of the invention are shown below.
The periphery of the guide post 2 is provided with threads, the fastening piece 4 is a nut, and the initial pretightening force can be kept to be applied to the battery cell by tightening the nut after pressurization is completed.
The pressurizing device 5 is a pressurizing device with pressure display, and can rapidly, real-timely and accurately acquire the pressure condition applied to the detection tool.
The above-mentioned film pressure sensor 6 is a piezoelectric film pressure sensor or a piezoresistive packet mode pressure sensor, and the area of the film pressure sensor 6 is larger than the area of the upper/lower surface of the cell 7 to be tested, so as to obtain more comprehensive and accurate test data. Meanwhile, the lead of the film type pressure sensor 6 is led out from the uncovered part of the battery cell 7 to be tested, and the pressure signal is transmitted to a pressure detecting instrument through the lead.
The above-mentioned lamination mode of the film-type pressure sensor 6 and the cell 7 to be measured may be that the film-type pressure sensor 6 is on the upper side, the cell 7 to be measured is under, or the film-type pressure sensor 6 is under, the cell 7 to be measured is on the upper side, that is, the film-type pressure sensor 6 is disposed on the upper surface of the base plate 1 or the lower surface of the pressing plate 3.
Further, when the film-type pressure sensor 6 is a strip-type, it is formed by a plurality of single pressure sensors, and the single pressure sensors are arranged on the surface of the to-be-measured cell 7 in an array form.
The battery cell 7 to be tested is a rectangular soft package or square shell battery, and the size and specification parameters of the shell are consistent with those of the battery model to be tested, so that the battery cell to be tested can be matched with the conventional clamp for the original practical use of the battery to be tested.
Through the scheme, after the pressing plate 3 is pressed by the pressing device 5, the thin film type pressure sensor 6 is calibrated to solve the problem of numerical drift, then the pressing device 5 is removed, fine adjustment of the fastening piece 4 is performed, the uniform distribution of the applied initial pretightening force is ensured, and the method has the following technical effects:
(1) the thin film type pressure sensor 6 is calibrated on software, so that the display of the thin film type pressure sensor 6 is truly and credible, and the problem of numerical drift of a pressure film is solved;
(2) the method can acquire the initial pretightening force value of the detection tool after the pressurizing device 5 is removed, and the problem that the real pretightening force is unknown after the locking is improved;
(3) the problem of uneven surface pressure of the battery cell 7 to be tested caused by different locking degrees due to separate locking of the fasteners 4 can be solved, and the initial force distribution of the surface of the battery cell 7 to be tested is obtained through the calibrated film type pressure sensor 6, so that the uniformity of the initial pretightening force of the surface of the battery cell 7 to be tested is ensured by fine adjustment of each fastener 4;
(4) the method is simple to use, can be directly used on the traditional detection tool, and does not need to improve the original detection tool.
The above examples and drawings are not intended to limit the form or form of the present invention, and any suitable variations or modifications thereof by those skilled in the art should be construed as not departing from the scope of the present invention.
Claims (10)
1. The method for uniformly applying the initial pretightening force to the battery cell comprises a bottom plate, a plurality of guide posts vertically connected to the bottom plate, a pressing plate sleeved on the guide posts in a lifting manner, a fastening piece arranged above the pressing plate and in threaded connection with the guide posts, and a pressurizing device arranged above the pressing plate; the method is characterized by comprising the following steps of:
step one, placing a film type pressure sensor and a cell to be tested in a center position between the pressing plate and the bottom plate in a lamination mode;
step two, applying pressure required by an experiment to the pressing plate through the pressurizing device, wherein the pressure value is N, the pressure value is M, and the fastening piece is locked;
step three, calibrating the film type pressure sensor on the software to enable the total display number of the film type pressure sensor to be N;
and step four, removing the pressurizing device, and performing fine adjustment on each fastener according to the distribution condition of the force on the film type pressure sensor, so that the pressure values of all the positions on the film type pressure sensor are equal and the pressure values of all the positions are M.
2. A method of uniformly applying an initial preload force to a cell as defined in claim 1, wherein:
in the first step, the thin film type pressure sensor is placed on the bottom plate, and then the battery cell to be tested is placed on the thin film type pressure sensor.
3. A method of uniformly applying an initial preload force to a cell as defined in claim 1, wherein:
in the first step, the battery cell to be measured is placed on the bottom plate, and then the film type pressure sensor is covered on the battery cell to be measured.
4. A method of uniformly applying an initial preload force to a cell as defined in claim 2 or 3, wherein:
the number of the film type pressure sensors is multiple, and the film type pressure sensors are arranged on the upper surface of the base plate or the upper surface of the battery cell to be tested in an array mode.
5. A method of uniformly applying an initial preload force to a cell as defined in claim 1, wherein:
the film type pressure sensor is a piezoelectric film type pressure sensor or a piezoresistance type packet mode pressure sensor.
6. A method of uniformly applying an initial preload force to a cell as defined in claim 1, wherein:
the area of the film type pressure sensor is larger than the areas of the upper surface and the lower surface of the battery cell to be measured.
7. A method of uniformly applying an initial preload force to a cell as defined in claim 1, wherein:
and a lead of the film type pressure sensor is led out from an uncovered part of the battery cell to be tested, and a pressure signal is transmitted to a pressure detection instrument through the lead.
8. A method of uniformly applying an initial preload force to a cell as defined in claim 1, wherein:
the periphery of the guide post is provided with threads, and the fastening piece is a nut.
9. A method of uniformly applying an initial preload force to a cell as defined in claim 1, wherein:
the pressurizing device is a pressurizing device with pressure display.
10. A method of uniformly applying an initial preload force to a cell as defined in claim 1, wherein:
the battery cell to be tested is a rectangular soft package or square shell battery.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310151335.2A CN116164869A (en) | 2023-02-22 | 2023-02-22 | Method for uniformly applying initial pretightening force to battery cell |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310151335.2A CN116164869A (en) | 2023-02-22 | 2023-02-22 | Method for uniformly applying initial pretightening force to battery cell |
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| CN116164869A true CN116164869A (en) | 2023-05-26 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202310151335.2A Pending CN116164869A (en) | 2023-02-22 | 2023-02-22 | Method for uniformly applying initial pretightening force to battery cell |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2011010571A1 (en) * | 2009-07-24 | 2011-01-27 | ローム株式会社 | Semiconductor pressure sensor, pressure sensor device, electronic apparatus, and method for manufacturing semiconductor pressure sensor |
| CN111122036A (en) * | 2019-12-17 | 2020-05-08 | 桑德新能源技术开发有限公司 | Cell cycle expansion detection method and detection device |
| CN111537126A (en) * | 2020-04-28 | 2020-08-14 | 苏州清陶新能源科技有限公司 | Tool for determining pretightening force of soft package battery, method for determining pretightening force of soft package battery and method for assembling module |
| CN211700459U (en) * | 2020-04-26 | 2020-10-16 | 苏州清陶新能源科技有限公司 | Battery module assembly fixture |
| CN214407841U (en) * | 2021-02-26 | 2021-10-15 | 蜂巢能源科技有限公司 | Cell cycle expansion force test tool |
| CN214426874U (en) * | 2021-03-30 | 2021-10-19 | 蜂巢能源科技有限公司 | Battery cell cyclic expansion force testing tool |
| CN217689045U (en) * | 2022-03-19 | 2022-10-28 | 联动天翼新能源有限公司 | Battery cell initial force applying device |
| CN218512594U (en) * | 2022-06-21 | 2023-02-21 | 北京车和家汽车科技有限公司 | Battery expansion testing device |
-
2023
- 2023-02-22 CN CN202310151335.2A patent/CN116164869A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011010571A1 (en) * | 2009-07-24 | 2011-01-27 | ローム株式会社 | Semiconductor pressure sensor, pressure sensor device, electronic apparatus, and method for manufacturing semiconductor pressure sensor |
| CN111122036A (en) * | 2019-12-17 | 2020-05-08 | 桑德新能源技术开发有限公司 | Cell cycle expansion detection method and detection device |
| CN211700459U (en) * | 2020-04-26 | 2020-10-16 | 苏州清陶新能源科技有限公司 | Battery module assembly fixture |
| CN111537126A (en) * | 2020-04-28 | 2020-08-14 | 苏州清陶新能源科技有限公司 | Tool for determining pretightening force of soft package battery, method for determining pretightening force of soft package battery and method for assembling module |
| CN214407841U (en) * | 2021-02-26 | 2021-10-15 | 蜂巢能源科技有限公司 | Cell cycle expansion force test tool |
| CN214426874U (en) * | 2021-03-30 | 2021-10-19 | 蜂巢能源科技有限公司 | Battery cell cyclic expansion force testing tool |
| CN217689045U (en) * | 2022-03-19 | 2022-10-28 | 联动天翼新能源有限公司 | Battery cell initial force applying device |
| CN218512594U (en) * | 2022-06-21 | 2023-02-21 | 北京车和家汽车科技有限公司 | Battery expansion testing device |
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