Method for measuring contact impedance of formation and capacity grading battery cabinet
Through the combination of MCU control units and measurement units, the core contact impedance is detected, the problem that the existing battery cabinet cannot detect the core contact status of the battery cabinet, and improves the quality and measurement accuracy of the battery cell.
Patent Information
- Application Number
- CN202411471486.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-22
- Publication Date
- 2025-01-24
AI Technical Summary
The existing battery cabinet cannot detect the contact state of the battery cell before the battery cell is transformed into or separated, resulting in abnormal contact between the battery cell and the power supply, increasing the risk of battery cell damage and production quality problems.
The combination of the MCU control unit, the constant current source, the measurement unit, and the measurement channel control unit, through measurement current and voltage, calculating contact impedance to achieve the detection and calibration of the battery contact state.
The quality of battery cell production is improved, the testing process is more professional, the impedance measurement is more accurate, and the cost is low. It can detect the contact status before the battery core is formed or divided into capacitances to ensure that it meets the requirements for formation and capacitance.
Smart Images
Figure CN119355381A_ABST
Abstract
Description
Technical Field
[0001] The present invention is applied to the technical field of capacity division, and in particular relates to a method for measuring the contact impedance of a capacity division battery cabinet. Background Art
[0002] The cell capacitation needs to ensure good contact between the power supply and the cell tabs, otherwise there may be test misjudgments during production, cell tabs overheating and damage, and other abnormalities, which will reduce the production qualification rate of the product. Especially for unformed cells, if the cell tabs are in abnormal contact with the formation power supply, and then the formation operation is performed, the cell will be damaged, and then the cell will be scrapped. Conventional battery cabinets only have the battery pressing function, but do not have the pressing state detection function. As a result, in actual application, the risk of damage to unformed cells and cell tabs is increased. Especially for soft-pack cells, the method of flat pressing on flat surfaces is adopted; the phenomenon of poor contact is particularly obvious, and poor pressing occurs, resulting in poor testing, and troubleshooting is particularly difficult. However, after the existing battery cabinet presses the battery, it does not perform the pressing detection function, but only performs the pressing action; the existing battery cabinet does not have the battery pressing impedance measurement function; the battery pressing state detection is performed by the power cabinet, but the power cabinet cannot complete the pressing impedance measurement before the test. Therefore, it is necessary to provide a method for measuring the contact impedance of a battery cabinet for capacity division, which has the advantages of low cost, more accurate impedance measurement, improved production quality of battery cells, and detection of whether the contact state of the battery cells meets the requirements of capacity division before the battery cells are formed or divided. Summary of the invention
[0003] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a method for measuring the contact impedance of a battery cabinet for capacity division, which has the advantages of low cost, more accurate impedance measurement, improved production quality of battery cells, and detection of whether the contact state of the battery cells meets the requirements of capacity division before the battery cells are formed or divided.
[0004] The technical solution adopted by the present invention is: the present invention comprises an MCU control unit, a constant current source, a measuring unit, and a measuring path control unit, wherein the MCU control unit is connected to an external host computer through communication, the MCU control unit is connected to the measuring path control unit via the constant current source and the measuring unit, the measuring path control unit is connected to the electrode plate, the electrode ear of the battery cell to be measured is connected to the electrode plate, and the measuring path control unit is connected to the electrode plate through a current line, a current feedback line, and a voltage line; the measuring method comprises the following steps: Step S1, the MCU control unit receives a measurement instruction from an external host computer; Step S2, the MCU control unit parses the test instruction; Step S3, controlling the measurement path control unit to connect to a corresponding physical link; Step S4, controlling the constant current source to output a fixed current; Step S5, the measuring unit accurately measures the actual current I and voltage U; Step S6: The MCU control unit calculates the contact impedance (R=U / I) of the link according to the actual data of the measuring unit.
[0005] It can be seen from the above scheme that the present application can detect whether the contact state of the battery cell meets the requirements of the formation or capacity division before the battery cell is formed or divided. At the same time, before the calibration of the capacity division power supply system, it can detect whether the battery cell pressing of the entire system meets the calibration requirements, which is beneficial to improving the production quality of the battery cell; the pressing detection process is more professional, the impedance measurement is more accurate and more targeted, and the measurement cost is low.
[0006] A preferred solution is that the measurement method includes the following subdivision steps: Step A, the measurement path control unit connects the current line and the voltage line, assuming that the current of the current line and the voltage line is I1, assuming that the voltage of the current line and the voltage line is U1, and the contact resistance of the current line and the voltage line is R1, R1=U1 / I1; Step B, the measurement path control unit connects the current line and the current feedback line, assuming that the current of the current line and the current feedback line is I2, assuming that the voltage of the current line and the current feedback line is U2, and the contact resistance of the current line and the current feedback line is R2, R2=U2 / I2; Step C, the measurement path control unit connects the voltage line and the current feedback line, assuming that the current of the voltage line and the current feedback line is I3, assuming that the voltage of the voltage line and the current feedback line is U3, and the contact resistance of the voltage line and the current feedback line is R3, R3=U3 / I3; Step D: From step A to step C, we know: The contact impedance of the voltage line: (R1+R3-R2) / 2 The contact impedance of the current line: (R1+R2-R3) / 2 The contact impedance of the current feedback line is: (R2+R3-R1) / 2.
[0007] A preferred solution is that the electrode plate includes a first resistor and a second resistor, the current line and the current feedback line are respectively connected to the two ends of the first resistor, the current line and the voltage line are respectively connected to the two ends of the second resistor, and the second resistor is connected to the pole ear of the battery cell to be tested; wherein the first resistor serves as the contact resistance of the current line and the current feedback line, and the second resistor serves as the contact resistance of the current line and the voltage line.
[0008] A preferred solution is that the MCU control unit is connected to an external communication unit, the MCU control unit is connected to an external host computer via the external communication unit, the MCU control unit receives the test requirements of the external host computer, and sends the measurement results to the external host computer. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 is a system block diagram of the present invention; Figure 2 It is a system test flow chart of the present invention; Figure 3 is a contact impedance measurement block diagram of the present invention; Figure 4 It is a flowchart of the impedance measurement process of the present invention; Figure 5 It is a block diagram of the contact resistance measurement principle of the present invention. DETAILED DESCRIPTION
[0010] like Figures 1 to 5 As shown, in this embodiment, the present invention includes an MCU control unit 1, a constant current source 2, a measuring unit 3, and a measuring path control unit 4. The MCU control unit 1 is connected to an external host computer for communication. The MCU control unit 1 is connected to the measuring path control unit 4 via the constant current source 2 and the measuring unit 3. The measuring path control unit 4 is connected to the plate 5. The pole ear of the battery cell to be measured is connected to the plate 5. The measuring path control unit 4 is connected to the plate 5 through a current line, a current feedback line, and a voltage line; wherein the current feedback line is referred to as a current feeder. The measuring method includes the following steps: Step S1, the MCU control unit 1 receives a measurement instruction from an external host computer; Step S2, the MCU control unit 1 parses the test instruction; Step S3, controlling the measurement path control unit 4 to connect to the corresponding physical link; Step S4, controlling the constant current source 2 to output a fixed current; Step S5, the measuring unit 3 accurately measures the actual current I and voltage U; Step S6: The MCU control unit 1 calculates the contact impedance (R=U / I) of the link according to the actual data of the measuring unit 3.
[0011] In this embodiment, the MCU control unit 1 is used to parse the test requirements sent by the master control system of the external host computer, and control the constant current source 2, the measurement unit 3 and the measurement path control unit 4 to complete the contact impedance measurement of the corresponding physical link according to the test requirements; and send the measurement results to the master control system; The constant current source 2 is used to output a fixed current through the physical path, generating a voltage at the input and output ends of the physical path. Different resistances of the physical path will generate different voltages; the current and voltage passing through the physical path are used as the basis for calculating the contact resistance.
[0012] The measuring unit 3 is used to measure the actual current and voltage generated by the current source in the physical path, and then calculate the contact impedance according to Ohm's law; The measurement path control unit 4 connects the constant current source 2 of the measuring device, the measuring unit 3 and the corresponding physical link of the battery cabinet according to the control signal of the MCU control unit 1 to prepare for the contact impedance measurement.
[0013] like Figures 1 to 5 As shown, in this embodiment, the measurement method includes the following subdivision steps: Step A, the measurement path control unit 4 connects the current line and the voltage line, assuming that the current of the current line and the voltage line is I1, assuming that the voltage of the current line and the voltage line is U1, and the contact resistance of the current line and the voltage line is R1, R1=U1 / I1; Step B, the measurement path control unit 4 connects the current line and the current feedback line, assuming that the current of the current line and the current feedback line is I2, assuming that the voltage of the current line and the current feedback line is U2, and the contact resistance of the current line and the current feedback line is R2, R2=U2 / I2; Step C, the measurement path control unit 4 connects the voltage line and the current feedback line, assuming that the current of the voltage line and the current feedback line is I3, assuming that the voltage of the voltage line and the current feedback line is U3, and the contact resistance of the voltage line and the current feedback line is R3, R3=U3 / I3; Step D: From step A to step C, we know: The contact impedance of the voltage line: (R1+R3-R2) / 2 The contact impedance of the current line: (R1+R2-R3) / 2 The contact impedance of the current feedback line is: (R2+R3-R1) / 2.
[0014] like Figures 1 to 5 As shown, in this embodiment, the electrode plate 5 includes a first resistor RA and a second resistor RB, the current line and the current feedback line are respectively connected to the two ends of the first resistor RA, the current line and the voltage line are respectively connected to the two ends of the second resistor RB, and the second resistor RB is connected to the pole ear of the battery cell to be tested; wherein, the first resistor RA serves as the contact resistance of the current line and the current feedback line, and the second resistor RB serves as the contact resistance of the current line and the voltage line.
[0015] like Figures 1 to 5 As shown, in this embodiment, the MCU control unit 1 is connected to an external communication unit 6, and the MCU control unit 1 is connected to an external host computer through the external communication unit 6. The MCU control unit 1 receives the test requirements of the external host computer and sends the measurement results to the external host computer. Although the embodiments of the present invention are described in terms of practical solutions, they do not constitute a limitation on the meaning of the present invention. For those skilled in the art, the modification of the implementation scheme and the combination with other schemes according to this specification are obvious.
Claims
1. A method for measuring the contact impedance of a battery cabinet with a capacity of 100% or more, characterized in that: The device comprises an MCU control unit (1), a constant current source (2), a measuring unit (3), and a measuring path control unit (4); the MCU control unit (1) is connected to an external host computer for communication; the MCU control unit (1) is connected to the measuring path control unit (4) via the constant current source (2) and the measuring unit (3); the measuring path control unit (4) is connected to a plate (5); the pole ear of the battery cell to be measured is connected to the plate (5); the measuring path control unit (4) is connected to the plate (5) via a current line, a current feedback line, and a voltage line; the measuring method comprises the following steps: Step S1, the MCU control unit (1) receives a measurement instruction from an external host computer; Step S2, the MCU control unit (1) parses the test instruction; Step S3, controlling the measurement path control unit (4) to connect to a corresponding physical link; Step S4, controlling the constant current source (2) to output a fixed current; Step S5, the measuring unit (3) accurately measures the actual current I and the voltage U; Step S6: The MCU control unit (1) calculates the contact impedance (R=U / I) of the link according to the actual data of the measuring unit (3).
2. The method for measuring contact impedance of a battery cabinet with a different capacity according to claim 1, characterized in that: The measurement method includes the following sub-steps: Step A, the measurement path control unit (4) connects the current line and the voltage line, assuming that the current of the current line and the voltage line is I1, assuming that the voltage of the current line and the voltage line is U1, and the contact resistance of the current line and the voltage line is R1, R1=U1 / I1; Step B, the measurement path control unit (4) connects the current line and the current feedback line, assuming that the current of the current line and the current feedback line is I2, assuming that the voltage of the current line and the current feedback line is U2, and the contact resistance of the current line and the current feedback line is R2, R2=U2 / I2; Step C, the measurement path control unit (4) connects the voltage line and the current feedback line, assuming that the current of the voltage line and the current feedback line is I3, assuming that the voltage of the voltage line and the current feedback line is U3, and the contact resistance of the voltage line and the current feedback line is R3, R3=U3 / I3; Step D: From step A to step C, we know: The contact impedance of the voltage line: (R1+R3-R2) / 2 The contact impedance of the current line: (R1+R2-R3) / 2 The contact impedance of the current feedback line is: (R2+R3-R1) / 2.
3. The method for measuring contact impedance of a battery cabinet with a different capacity according to claim 1, characterized in that: The electrode plate (5) comprises a first resistor (RA) and a second resistor (RB), the current line and the current feedback line are respectively connected to the two ends of the first resistor (RA), the current line and the voltage line are respectively connected to the two ends of the second resistor (RB), and the second resistor (RB) is connected to the tab of the battery cell to be tested; wherein the first resistor (RA) serves as a contact resistor for the current line and the current feedback line, and the second resistor (RB) serves as a contact resistor for the current line and the voltage line.
4. The method for measuring contact impedance of a battery cabinet with a different capacity according to claim 1, characterized in that: The MCU control unit (1) is connected to an external communication unit (6), and the MCU control unit (1) is connected to an external host computer via the external communication unit (6). The MCU control unit (1) receives a test request from the external host computer and sends a measurement result to the external host computer.