Lithium battery needling positioning tool

Abstract

The utility model provides a lithium battery needling positioning tool. The tool comprises an electric wire, a metal needle, an acquisition instrument, an upper computer and a lithium battery to be tested, the upper computer is connected with the acquisition instrument, two sides of the acquisition instrument are respectively connected with the metal needle and the lithium battery to be tested through the electric wires, and the metal needle is used for needling the lithium battery to be tested. According to the lithium battery needling positioning tool, other measuring tools do not need to be introduced, a voltage jump signal generated between the metal needle and the lithium battery to be measured is directly used as a feedback signal of a needling zero point, the error is small, and the operation is simple. According to the lithium battery needling positioning tool disclosed by the utility model, equipment does not need to be started and the tool does not need to be disassembled for many times, and after the tool is assembled, the equipment is directly started to perform needling on the lithium battery to be tested; the process is continuously carried out, no potential safety hazard exists, and the testing efficiency is high.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium battery testing, in particular to a lithium battery needle puncture positioning tool. Background Art

[0002] With the continuous expansion of the application of lithium batteries in electric vehicles, energy storage and other fields, the efficiency and service life of batteries are constantly being improved. The requirements for the energy density, fast charging and discharging of lithium batteries are also constantly increasing. The safety performance of lithium batteries has attracted the attention of the industry. As we all know, the attenuation of lithium batteries in normal use cycles and the abuse under abnormal use conditions may cause internal and external short circuits, thereby causing the self-generation of heat in lithium batteries. When the heat generation is greater than the heat dissipation, thermal runaway will occur, and even worse, it will cause battery exhaust, fire, and explosion, causing personal injury and property safety. In order to study and evaluate the safety performance of lithium batteries, acupuncture is usually used to simulate the problem of internal short circuit caused by lithium batteries under mechanical destruction. The possible severity of internal short circuit is controlled by controlling the depth, speed, and diameter of the steel needle. Many research reports have shown that the deeper the penetration depth, the more layers of the pole piece short circuit, and the more severe the internal short circuit. In order to study the situation of internal short circuits of different degrees, different penetration depths are used for adjustment. The thickness of the pole piece is at the um level, so higher requirements are put forward for the control accuracy of the penetration depth.

[0003] The existing technologies include visual zero point calibration, combined measurement techniques or conductive plates with tooling. All three methods have large measurement errors and complex operations.

[0004] 1) The specific operation of visual calibration of zero point is to start the movement at a lower speed after the sample is assembled. When the steel needle just touches the surface of the battery, stop the equipment and mark this position as the zero point. At least two people are required to cooperate during the test, one to check the position of the steel needle and the other to operate the equipment; visual judgment of whether the steel needle just touches the surface of the battery is subjective and the error is large; there are high safety hazards, and if the communication between personnel is not timely or the equipment fails, it is very easy to cause the steel needle to pierce the battery. Therefore, visual calibration of zero point is complicated, with large errors and safety hazards.

[0005] 2) The specific operation of the combined measurement method is to use a vernier caliper to measure the distance between the tip of the steel needle and the surface of the battery. Because the caliper and the steel needle are not on the same concentric axis, eccentric measurement will cause a large measurement error.

[0006] 3) The conductive plate is combined with a tooling to operate in such a way that after it is detected that the steel needle contacts the conductive plate and generates an electrical signal, the steel needle is retracted, the circuit board and the tooling are removed, and then the needle is continued to be inserted and retracted by a distance equal to the thickness of the processing device plus the actual insertion depth. This method introduces measurement errors and requires repeated disassembly of the stand, which is complicated to operate and inefficient. The name of the prior art Chinese patent is "A high-precision acupuncture test device and method for lithium-ion batteries based on electrical signals" (application number CN115656852A), which uses a conductive plate with a tooling (thickness L1), stops after detecting the electrical signal, the steel needle is retracted to L2, and then the tooling is removed, and then the travel displacement is reset to L1+L2+X before acupuncture is performed. Utility Model Content

[0007] The technical problem to be solved by the utility model is how to reduce measurement errors and simplify operation steps.

[0008] The utility model solves the above technical problems through the following technical means:

[0009] The utility model provides a lithium battery needle puncture positioning tool, which comprises a host computer, a collector, a metal needle and an electric wire; the host computer is connected to the collector, and the two sides of the collector are respectively connected to the metal needle and the lithium battery to be tested through the electric wire, and the metal needle punctures the lithium battery to be tested.

[0010] Beneficial effect: The lithium battery puncture positioning tool of the utility model does not need to introduce other measuring tools. It directly uses the voltage mutation signal generated between the metal puncture and the lithium battery to be tested as the feedback signal of the puncture zero point, with small error and simple operation.

[0011] The lithium battery needle puncture positioning tooling of the utility model does not need to open the equipment and disassemble the tooling many times. After the tooling is equipped, the equipment is directly turned on to needle-puncture the lithium battery to be tested. This process is carried out continuously without any safety hazards and has a high test efficiency.

[0012] Preferably, the collector is connected to the positive electrode of the lithium battery to be tested.

[0013] Preferably, the metal needle is located above the lithium battery to be tested.

[0014] Preferably, the metal needle punctures the lithium battery to be tested at a set puncture speed and depth.

[0015] Preferably, the penetration speed is 0.01-1 mm / s; and the depth is 0-30 mm.

[0016] Preferably, the metal needle pierces the insulating film, the aluminum shell, the mylar, and the diaphragm in sequence, and contacts with the negative electrode to generate a sudden voltage signal.

[0017] Preferably, the metal needles are steel needles, aluminum needles or copper needles.

[0018] Preferably, the lithium battery to be tested is a square-shell hard-shell battery.

[0019] Preferably, the data collector is Hioki's new data collector LR8450 model or Ganna's Q.station model.

[0020] Preferably, the metal needle puncture is performed on the lithium battery to be tested by a needle puncture tester.

[0021] The advantages of the utility model are:

[0022] The lithium battery needle puncture positioning tool of the utility model does not need to introduce other measuring tools, and directly uses the voltage signal generated between the metal needle and the lithium battery to be measured as the feedback signal of the needle puncture zero point, with small error and simple operation.

[0023] The lithium battery needle puncture positioning tooling of the utility model does not need to open the equipment and disassemble the tooling many times. After the tooling is equipped, the equipment is directly turned on to needle-puncture the lithium battery to be tested. This process is carried out continuously without any safety hazards and has a high test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic diagram of the lithium battery acupuncture positioning tooling of Example 1;

[0025] Figure 2 This is a schematic diagram of the interior of a lithium battery to be tested during the acupuncture process of Example 1;

[0026] Figure 3 is a schematic diagram of an equivalent circuit of Example 1;

[0027] Figure numerals: 1-host computer; 2-collector; 3-metal puncture; 4-lithium battery to be tested; 5-electric wire; the direction of the arrow indicates the puncture direction. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the utility model clearer, the technical solution in the embodiments of the utility model will be clearly and completely described below in combination with the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] If no specific techniques or conditions are specified in the examples, they can be carried out according to the techniques or conditions described in the literature in the art or according to the product instructions.

[0030] Example 1

[0031] As attached Figure 1-3 As shown, this embodiment provides a lithium battery needle puncture positioning tool, which includes a host computer 1, a collector 2, a metal needle puncture 3, a lithium battery to be tested 4 and an electric wire 5. The host computer 1 is connected to the collector 2, and the two sides of the collector 2 are respectively connected to the metal needle puncture 3 and the lithium battery to be tested 4 through the electric wire 5. The metal needle puncture 3 is located above the lithium battery to be tested 4, and the lithium battery to be tested 4 is needled.

[0032] The host computer 1 is a computer that issues control commands, which can be an industrial computer or a touch screen; the host computer 1 is connected to the data collector 2 through a wire 5. The data collector 2 generally uses the Hioki new data collector LR8450 model, including two modules U8552 and U8550. The data collector 2 in this embodiment uses the Ganna Q.station model, including three modules A104, A107, and A108; those skilled in the art can select modules according to their needs.

[0033] The collector 2 is connected to the metal needle 3 through the wire 5, and the metal needle 3 is a steel needle, an aluminum needle or a copper needle.

[0034] The collector 2 is connected to the lithium battery 4 to be tested through the wire 5. The collector 2 is connected to the positive electrode of the lithium battery 4 to be tested. When the metal needle 3 pierces the negative electrode of the lithium battery 4 to be tested, a complete circuit is formed. The metal needle 3 pierces the insulating film, aluminum shell, mylar, and diaphragm of the lithium battery 4 to be tested in turn, and contacts with the negative electrode to generate a sudden voltage signal.

[0035] The collector 2 is used to collect the voltage change of the circuit. The host computer 1 monitors the voltage change collected by the collector 2. If the voltage suddenly changes, it means that the metal needle 5 penetrates the negative electrode of the lithium battery 4 to reach the zero point of the needle.

[0036] The host computer 1 knows that the metal needle puncture 3 reaches the puncture zero point through the voltage signal collected by the collector 2. At this time, the metal needle puncture 3 continues to puncture the lithium battery 4 to be tested according to the puncture speed and depth set by the host computer 1. The metal needle puncture 3 is driven by the motor of the puncture tester to puncture the lithium battery 4 to be tested.

[0037] The operation method of the lithium battery needle puncture positioning tool in this embodiment has the following specific steps:

[0038] (1) According to the attached Figure 1 As shown, the lithium battery needle puncture positioning tool is assembled, and the upper computer 1, the collector 2, the metal needle puncture 3, and the lithium battery to be tested 4 are connected in sequence using the wire 5.

[0039] (2) The host computer 1 sets the parameters of the penetration speed and depth of the metal needle 3 according to the test requirements.

[0040] (3) Open the tooling and conduct the test, as shown in the attached Figure 2 As shown, it is a schematic diagram of the metal needle 3 piercing into the interior of the lithium battery 4 to be tested during the puncture process. The metal needle 3 pierces the insulating film, the aluminum shell, the mylar, and the separator in sequence, and contacts the negative electrode.

[0041] (4) Then Figure 3 As shown in the equivalent circuit diagram, a voltage mutation occurs after the metal needle 3 contacts the negative electrode of the lithium battery 4 to be tested. After this signal is fed back to the host computer 1, this moment can be located as the puncture zero point, and then the metal needle 3 continues to puncture at the set puncture speed and depth.

[0042] The utility model forms a complete circuit among the metal needle puncture, the collector and the lithium battery to be tested. Only by observing the voltage change in the collector, it is possible to know when the metal needle punctures the zero point. This can achieve the goal of not introducing additional measurement errors. According to the research and development requirements and the thickness of the battery electrode, the number of electrode layers to be punctured is calculated, and the penetration depth is set, with high test accuracy.

[0043] The utility model can realize program zero point positioning and continuous acupuncture battery action by receiving a voltage mutation as the acupuncture zero point in the upper computer and then continuing to puncture the set depth according to the set program, without pausing the test step or the operation of tooling disassembly, and the test efficiency is high.

[0044] The utility model uses the voltage signal generated between the metal needle and the lithium battery to be tested as the feedback needle zero point model. When the lithium battery needle positioning tooling is assembled, the explosion-proof box and the test area door are closed, and the program can automatically complete the zero point positioning and needle test. Personnel do not need to approach the test area for visual observation throughout the process, and the test safety is relatively high.

[0045] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A lithium battery acupuncture positioning tool, characterized in that: It includes a host computer (1), a collector (2), a metal needle (3) and an electric wire (5); The host computer (1) is connected to a collector (2), and the two sides of the collector (2) are respectively connected to the metal needle puncture (3) and the lithium battery to be tested (4) through the electric wire (5), and the metal needle puncture (3) punctures the lithium battery to be tested (4).

2. The lithium battery acupuncture positioning tool according to claim 1, characterized in that: The collector (2) is connected to the positive electrode of the lithium battery (4) to be tested.

3. The lithium battery acupuncture positioning tool according to claim 1, characterized in that: The metal needle (3) is located above the lithium battery (4) to be tested.

4. The lithium battery acupuncture positioning tool according to claim 3, characterized in that: The metal needle puncture (3) punctures the lithium battery (4) to be tested according to a set puncture speed and depth.

5. The lithium battery acupuncture positioning tool according to claim 1, characterized in that: The metal needle (3) sequentially pierces the insulating film, aluminum shell, mylar, and separator of the lithium battery (4) to be tested, and contacts the negative electrode.

6. The lithium battery acupuncture positioning tool according to claim 1, characterized in that: The metal needle (3) is a steel needle, an aluminum needle or a copper needle.

7. The lithium battery acupuncture positioning tool according to claim 1, characterized in that: The lithium battery (4) to be tested is a square-shell hard-shell battery.

8. The lithium battery acupuncture positioning tool according to claim 3, characterized in that: The insertion speed is 0.01 to 1 mm / s; the insertion depth is 0 to 30 mm.

9. The lithium battery acupuncture positioning tool according to claim 1, characterized in that: The data collector (2) is a Hioki new data collector LR8450 model or a Ganna Q.station model.

10. The lithium battery acupuncture positioning tool according to claim 1, characterized in that: The metal needle puncture (3) is performed on the lithium battery (4) to be tested by using a needle puncture test machine.

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