Hot-pressing short circuit detection device suitable for lithium ion battery

Abstract

The hot-pressing short circuit detection device comprises an upper hot-pressing table and a lower hot-pressing table, and the lower surface of the upper hot-pressing table and the upper surface of the lower hot-pressing table are respectively provided with a temperature sensor and a pressure sensor. Short-circuit detection probes are arranged at the two ends of the upper hot-pressing table, and ports of the short-circuit detection probes are cylindrical smooth ports. The short-circuit detection probe is installed on the upper hot-pressing table through a spring scaling mechanism, and limiting blocks are arranged at the two ends of the lower hot-pressing table and used for positioning a to-be-detected battery cell. According to the utility model, temperature and pressure changes during hot pressing of the battery cell can be monitored in real time, fine adjustment compensation is carried out according to actual values, and hot pressing consistency is ensured; according to the invention, the short-circuit detection probe can be prevented from generating contact indentations on the foil to the greatest extent, the battery cells with different thicknesses can be detected in a compatible manner, the contact effect is good, the detection precision is high, and the quality and the safety of the battery cells are ensured.

Description

Technical Field

[0001] The utility model belongs to the technical field of lithium ion batteries, and in particular relates to a thermal pressure short circuit detection device suitable for lithium ion batteries. Background Art

[0002] Lithium-ion battery is a secondary battery (rechargeable battery) that mainly relies on the movement of lithium ions between the positive and negative electrodes to work. + Insertion and deinsertion back and forth between the two electrodes: During charging, Li + It is deintercalated from the positive electrode and intercalated into the negative electrode through the electrolyte, and the negative electrode is in a lithium-rich state; the opposite is true during discharge.

[0003] When short circuit is detected at the end of stacking, existing battery cells will place hot pressing and short circuit at the same workstation and carry out them simultaneously. However, it is impossible to know the temperature and pressure conditions on the hot pressing table during the operation, and it is impossible to judge the stress and temperature change trends of the stacked cores. There may be stacked cores with poor hot pressing. Secondly, many probes of existing equipment are block-type, which will produce indentations on the tab foil of the stacked core, resulting in great risks in the subsequent tab welding. Moreover, the block-type probes are fixed and cannot be compatible with different battery cell thicknesses. Utility Model Content

[0004] The purpose of the utility model is to provide a thermal compression short circuit detection device suitable for lithium ion batteries to solve one or more problems raised in the above background technology.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A hot pressing short circuit detection device suitable for lithium ion batteries comprises an upper hot pressing platform and a lower hot pressing platform, wherein the lower surface of the upper hot pressing platform and the upper surface of the lower hot pressing platform are both installed with a temperature sensor and a pressure sensor, wherein the temperature sensor is used to monitor the temperature change trend of the upper hot pressing platform and the lower hot pressing platform in real time, and the pressure sensor is used to monitor the pressure change trend of the upper hot pressing platform and the lower hot pressing platform in real time.

[0007] Furthermore, short-circuit detection probes are provided at both ends of the upper hot-pressing platform, and the ports of the short-circuit detection probes are cylindrical smooth ports.

[0008] Furthermore, mounting end plates are provided at both ends of the upper hot pressing platform, and the short circuit detection probe is mounted on the mounting end plates.

[0009] Furthermore, the short-circuit detection probe is mounted on the mounting end plate via a spring-scaling mechanism, and the spring-scaling mechanism is used to expand and contract as the contact distance between the upper hot pressing platform and the battery cell to be tested changes.

[0010] Furthermore, limit blocks are provided at both ends of the lower hot pressing platform for positioning the battery cell to be tested.

[0011] Furthermore, support rods are provided on both sides of the lower hot press platform, a connecting plate is provided above the upper hot press platform, the upper hot press platform is fixedly connected to the connecting plate, guide sleeves are provided on both sides of the connecting plate, the support rods pass through the guide sleeves and are movably connected to the guide sleeves through clearance fit, and a cylinder is fixedly connected above the connecting plate.

[0012] Furthermore, the hot pressing short circuit detection device suitable for lithium ion batteries further includes a base, and the lower hot pressing platform and the support rod are both mounted on the base.

[0013] Furthermore, an upper mounting plate is provided above the cylinder, the upper end of the support rod is fixedly connected to the upper mounting plate, and the cylinder is mounted on the upper mounting plate.

[0014] Compared with the prior art, the utility model has the following beneficial effects:

[0015] The utility model can monitor the changes of pressure and temperature in real time during hot pressing, and make fine adjustments and compensations according to the actual values ​​monitored to ensure the consistency of hot pressing; at the same time, the utility model uses a short-circuit detection probe with a cylindrical smooth port to test the short circuit of the battery cell, which can avoid the probe from causing contact indentation on the battery cell tab foil to the greatest extent, thereby ensuring the quality and safety of the battery cell. In addition, the short-circuit detection probe of the utility model adopts a spring-scaling mechanism, which is compatible with the detection of batteries of different thicknesses, has stronger tolerance and higher stability, and the contact effect between the probe and the battery cell tab is good, and the detection accuracy is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the utility model.

[0017] In the figure: 11, upper hot pressing platform; 12, lower hot pressing platform; 13, temperature sensor; 14, pressure sensor; 15, limit block; 2, battery cell to be tested; 31, cylinder; 32, upper mounting plate; 33, support rod; 34, guide sleeve; 35, connecting plate; 36, connecting shaft; 41, spring telescopic mechanism; 42, short circuit detection probe; 43, mounting end plate; 5, base. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments, and cannot be used to limit the protection scope of the present invention.

[0019] like Figure 1As shown, a hot pressing short circuit detection device suitable for lithium ion batteries includes a hot pressing system and a short circuit detection system.

[0020] The hot pressing system includes an upper hot pressing platform 11 and a lower hot pressing platform 12 .

[0021] The lower hot pressing platform 12 is arranged on the base 5 .

[0022] A connecting plate 35 is disposed above the upper hot pressing platform 11 , and the upper hot pressing platform 11 is fixedly connected to the connecting plate 35 via a connecting shaft 36 .

[0023] An upper mounting plate 32 is disposed above the connecting plate 35, a cylinder 31 is disposed between the upper mounting plate 32 and the connecting plate 35, the cylinder 31 is mounted on the upper mounting plate 32, and the output shaft of the cylinder 31 is connected to the connecting plate 35. The hot press table applies pressure to the battery cell through the cylinder 31 as a driving device.

[0024] Support rods 33 are arranged on both sides of the lower hot pressing platform 12 .

[0025] The upper end of the support rod 33 is connected to the upper mounting plate 32 , and the lower end is connected to the base 5 .

[0026] Guide sleeves 34 are installed at both ends of the connecting plate 35 , and the guide sleeves 34 can be fixed on the connecting plate 35 by snap-fitting or other connection methods.

[0027] The support rod 33 passes through the guide sleeve 34 and is movably connected to the guide sleeve 34 through clearance fit, ensuring that the connecting plate 35 can move up and down along the support rod 33 under the drive of the cylinder 31, thereby driving the upper hot pressing table 11 to perform hot pressing reciprocating motion.

[0028] like Figure 1 As shown, a temperature sensor 13 and a pressure sensor 14 are installed on the lower surface of the upper hot pressing platform 11, which are respectively used to monitor the temperature change trend and the pressure change trend of the upper hot pressing platform 11 in real time during the hot pressing process.

[0029] A temperature sensor 13 and a pressure sensor 14 are also installed on the upper surface of the lower hot pressing platform 12, which are used to monitor the temperature change trend and the pressure change trend of the lower hot pressing platform 12 in real time during the hot pressing process.

[0030] The temperature sensor 13 and the pressure sensor 14 are both connected to the controller. The controller is used to fine-tune and compensate the temperature and / or pressure of the upper hot pressing platform 11 and the lower hot pressing platform 12 according to the temperature and pressure values ​​monitored by the temperature sensor 13 and the pressure sensor 14.

[0031] After placing the core stack on the lower hot press table 12 and turning on the hot press function, the temperature sensor 13 and the pressure sensor 14 on the hot press table start working to monitor the temperature and pressure changes of the hot press table in real time. When the pressure or temperature exceeds the range, the system will fine-tune the parameters to compensate so that the pressure or temperature returns to the set process range.

[0032] By real-time monitoring of the temperature and pressure changes of the upper hot pressing platform 11 and the lower hot pressing platform 12 during the hot pressing process, and performing fine-tuning compensation processing according to the actual monitored temperature and pressure values, the hot pressing temperature and pressure of the upper hot pressing platform 11 and the lower hot pressing platform 12 can be ensured to be consistent, thereby avoiding the occurrence of poorly hot-pressed core stacks.

[0033] like Figure 1 As shown, mounting end plates 43 are provided on both sides of the upper hot pressing platform 11, and short circuit detection probes 42 are installed on the mounting end plates 43. The ports of the short circuit detection probes 42 are cylindrical smooth ports. The short circuit detection probes 42 use cylindrical smooth ports to avoid indentations on the surface of the cell tab foil during short circuit detection.

[0034] In a further embodiment, the short circuit detection probe 42 is mounted on the mounting end plate 43 via a spring-scaling mechanism 41. One end of the spring-scaling mechanism 41 is fixed on the mounting end plate 43, and the other end is connected to the short circuit detection probe 42.

[0035] The spring-scaling mechanism 41 can expand and contract as the contact distance between the hot pressing platform and the battery cell changes when the hot pressing platform contacts the battery cell, thereby ensuring that the top of the short-circuit detection probe 42 can adaptively contact the battery cell tab foil, thereby achieving compatibility detection of battery cells of different thicknesses.

[0036] like Figure 1 As shown, limit blocks 15 are also provided at both ends of the lower hot pressing platform 12, and the battery cell 2 to be tested is placed between the two limit blocks 15. The limit blocks 15 are used to position the battery cell 2 to be tested to prevent the battery cell 2 to be tested from shifting during the hot pressing process.

[0037] The working principle of the utility model is as follows:

[0038] The battery cell to be tested is placed on the lower hot pressing platform 12, and the limit blocks 15 at both ends of the lower hot pressing platform 12 are used to preliminarily position the battery cell. The cylinder 31 is used as a driving device to apply pressure to the battery cell. At the same time, the upper and lower hot pressing platforms 11 and 12 heat the battery cell to complete the hot pressing process. During the hot pressing process, the temperature sensor 13 and the pressure sensor 14 monitor the temperature and pressure changes of the upper and lower hot pressing platforms 11 and 12 in real time, and adjust the real-time value of the compensation parameter in time. While the hot pressing platform is pressed down, the short-circuit detection probe 42 automatically adjusts the distance from the battery cell tab according to the thickness of the battery cell through the spring telescopic mechanism 41, so that the top of the short-circuit detection probe 42 can adaptively contact the battery cell tab foil, and the short-circuit detection is performed at the end of the hot pressing.

[0039] The utility model can monitor the changes of pressure and temperature in real time during hot pressing, and make fine adjustments and compensations according to the actual values ​​monitored to ensure the consistency of hot pressing; at the same time, the utility model uses a short-circuit detection probe with a cylindrical smooth port to test the short circuit of the battery cell, which can avoid the probe from causing contact indentation on the battery cell tab foil to the greatest extent, thereby ensuring the quality and safety of the battery cell. In addition, the short-circuit detection probe of the utility model adopts a spring-scaling mechanism, which is compatible with the detection of batteries of different thicknesses, has stronger tolerance and higher stability, and the contact effect between the probe and the battery cell tab is good, and the detection accuracy is higher.

[0040] The present invention has been disclosed as a preferred embodiment above, but it is not intended to limit the present invention. Any technical solution obtained by adopting equivalent replacement or equivalent transformation solutions falls within the protection scope of the present invention.

Claims

1. A thermal pressure short circuit detection device suitable for lithium ion batteries, characterized in that: The invention comprises an upper hot pressing platform (11) and a lower hot pressing platform (12), wherein a temperature sensor (13) and a pressure sensor (14) are installed on the lower surface of the upper hot pressing platform (11) and the upper surface of the lower hot pressing platform (12), respectively; the temperature sensor (13) is used for real-time monitoring of the temperature change trend of the upper hot pressing platform (11) and the lower hot pressing platform (12), and the pressure sensor (14) is used for real-time monitoring of the pressure change trend of the upper hot pressing platform (11) and the lower hot pressing platform (12).

2. The thermal pressure short circuit detection device suitable for lithium ion batteries according to claim 1, characterized in that: Short circuit detection probes (42) are arranged at both ends of the upper hot pressing platform (11), and the ports of the short circuit detection probes (42) are cylindrical smooth ports.

3. The thermal pressure short circuit detection device suitable for lithium ion batteries according to claim 2, characterized in that: Mounting end plates (43) are provided at both ends of the upper hot pressing platform (11), and the short circuit detection probe (42) is mounted on the mounting end plates (43).

4. The thermal pressure short circuit detection device suitable for lithium ion batteries according to claim 3, characterized in that: The short circuit detection probe (42) is mounted on the mounting end plate (43) via a spring-scaling mechanism (41), and the spring-scaling mechanism (41) is used to expand and contract as the contact distance between the upper hot pressing platform (11) and the battery cell (2) to be tested changes.

5. The thermal pressure short circuit detection device for lithium ion batteries according to any one of claims 1 to 4, characterized in that: Limiting blocks (15) are provided at both ends of the lower hot pressing platform (12) for positioning the battery cell (2) to be tested.

6. The thermal pressure short circuit detection device for lithium ion batteries according to any one of claims 1 to 4, characterized in that: Support rods (33) are arranged on both sides of the lower hot pressing platform (12), a connecting plate (35) is arranged above the upper hot pressing platform (11), the upper hot pressing platform (11) is fixedly connected to the connecting plate (35), guide sleeves (34) are arranged on both sides of the connecting plate (35), the support rods (33) pass through the guide sleeves (34) and are movably connected to the guide sleeves (34) through clearance fit, and a cylinder (31) is fixedly connected above the connecting plate (35).

7. The thermal pressure short circuit detection device for lithium ion batteries according to claim 6, characterized in that: It also includes a base (5), and the lower hot pressing platform (12) and the support rod (33) are both installed on the base (5).

8. The thermal pressure short circuit detection device for lithium ion batteries according to claim 6, characterized in that: An upper mounting plate (32) is arranged above the cylinder (31), the upper end of the support rod (33) is fixedly connected to the upper mounting plate (32), and the cylinder (31) is mounted on the upper mounting plate (32).

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