CN113125974B - Method and device for detecting lithium precipitation of battery - Google Patents
Method and device for detecting lithium precipitation of battery Download PDFInfo
- Publication number
- CN113125974B CN113125974B CN202110438295.0A CN202110438295A CN113125974B CN 113125974 B CN113125974 B CN 113125974B CN 202110438295 A CN202110438295 A CN 202110438295A CN 113125974 B CN113125974 B CN 113125974B
- Authority
- CN
- China
- Prior art keywords
- negative electrode
- potential
- current
- battery
- charge
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R31/385—Arrangements for measuring battery or accumulator variables
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R31/378—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC] specially adapted for the type of battery or accumulator
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/36—Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
- G01R31/385—Arrangements for measuring battery or accumulator variables
- G01R31/387—Determining ampere-hour charge capacity or SoC
- G01R31/388—Determining ampere-hour charge capacity or SoC involving voltage measurements
-
- 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
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Secondary Cells (AREA)
Abstract
The embodiment of the invention discloses a method and a device for detecting lithium precipitation of a battery, wherein the method comprises the following steps: charging the three-electrode battery by adopting a preset first current to obtain a first charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential; charging the three-electrode battery by adopting a preset second current to obtain a second charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential; determining a first negative electrode potential and a second negative electrode potential corresponding to the first state of charge and the second state of charge respectively based on the corresponding relation between the states of charge and the negative electrode potentials; and determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential, so as to determine lithium precipitation windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the charge state and the negative electrode potential. The method and the device for detecting the lithium separation of the battery can improve the efficiency and the convenience of detecting the lithium separation of the battery.
Description
Technical Field
The embodiment of the invention relates to a battery detection technology, in particular to a method and a device for detecting lithium precipitation of a battery.
Background
In recent years, with the rapid development of electric vehicles, mileage anxiety becomes a key factor limiting large-scale popularization of the electric vehicles, and two directions of solving the continuous voyage of the electric vehicles are mainly to improve the energy density of batteries and shorten the charging time of the batteries. The key risk point of shortening the battery charging time, i.e. fast charging, is that lithium is extracted from the negative electrode, and the state of charge that can be achieved by the battery under different current charging conditions needs to be obtained.
At present, the existing battery lithium precipitation detection method is generally used for testing lithium precipitation windows under different currents, and when the lithium precipitation windows under different currents are tested, the charge states of batteries corresponding to the currents are required to be tested one by one, so that the workload is large, and the detection efficiency and convenience are affected.
Disclosure of Invention
The embodiment of the invention provides a method and a device for detecting lithium separation of a battery, which are used for improving the efficiency and convenience of lithium separation detection of the battery.
In a first aspect, an embodiment of the present invention provides a method for detecting lithium precipitation of a battery, including:
acquiring a corresponding relation between a charge state and a negative electrode potential of the three-electrode battery in a charging process;
charging the three-electrode battery by adopting a preset first current to obtain a first charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential;
charging the three-electrode battery by adopting a preset second current to obtain a second charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential;
determining a first negative electrode potential and a second negative electrode potential corresponding to the first state of charge and the second state of charge respectively based on the corresponding relation between the states of charge and the negative electrode potentials; wherein the negative potential is positively correlated with the logarithm of the current;
and determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential, so as to determine lithium precipitation windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the charge state and the negative electrode potential.
Optionally, determining the first negative electrode potential and the second negative electrode potential corresponding to the first state of charge and the second state of charge respectively based on the correspondence between the states of charge and the negative electrode potentials includes:
drawing a relationship curve of the state of charge and the negative electrode potential based on the obtained corresponding relationship of the state of charge and the negative electrode potential;
and determining a first negative electrode potential and a second negative electrode potential respectively corresponding to the first charge state and the second charge state according to the relation curve of the charge state and the negative electrode potential.
Optionally, determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential includes:
will preset a first current I 1 And a first negative electrode potential OCV Negative 1 Substituting OCV Negative pole =a+blgi, and will preset a second current I 2 And a second negative electrode potential OCV Negative 2 Substituting OCV Negative pole =a+blgi, resulting in values of a and b;
determining the relation between the potential of the negative electrode and the current according to the values of a and b; wherein, the negative electrode potential OCV of the three-electrode battery Negative pole =a+blgi, I is current, and a and b are both coefficients.
Optionally, determining the lithium precipitation window corresponding to different currents based on the relationship between the anode potential and the current and the corresponding relationship between the state of charge and the anode potential includes:
determining the corresponding relation between the current and the state of charge based on the relation between the potential of the negative electrode and the current and the corresponding relation between the state of charge and the potential of the negative electrode;
and determining lithium precipitation windows corresponding to different currents according to the corresponding relation between the currents and the states of charge.
Optionally, before obtaining the corresponding relationship between the charge state and the negative electrode potential of the three-electrode battery in the charging process, the method includes:
and charging the three-electrode battery with a preset multiplying power of the capacity of the three-electrode battery, and determining the corresponding relation between the charge state of the three-electrode battery in the charging process and the negative electrode potential.
Optionally, the three-electrode battery is charged with the C1 multiplying power of the three-electrode battery capacity C, and the value range of C1 is 0.01-0.1C.
Optionally, the preset first current and the preset second current are respectively a minimum current and a maximum current corresponding to the target lithium precipitation window.
Alternatively, the negative cutoff potential phi of a three-electrode battery Negative pole ＝E Li+/Li -η Li+/Li ,E Li+/Li Is 0V, eta Li+/Li 0-200mV.
In a second aspect, an embodiment of the present invention further provides a device for detecting lithium precipitation of a battery, including:
the potential acquisition module is used for acquiring the corresponding relation between the charge state of the three-electrode battery in the charging process and the potential of the negative electrode;
the first charge state acquisition module is used for charging the three-electrode battery by adopting a preset first current to acquire a first charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential;
the second charge state acquisition module is used for charging the three-electrode battery by adopting a preset second current to acquire a second charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential;
the potential determining module is used for determining a first negative electrode potential and a second negative electrode potential which correspond to the first charge state and the second charge state respectively based on the corresponding relation between the charge state and the negative electrode potential; wherein the negative potential is positively correlated with the logarithm of the current;
the window determining module is used for determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential so as to determine lithium precipitation windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the charge state and the negative electrode potential.
Optionally, the potential determining module includes:
the curve drawing unit is used for drawing a relation curve of the charge state and the negative electrode potential based on the obtained corresponding relation of the charge state and the negative electrode potential;
and the potential determining unit is used for determining a first negative electrode potential and a second negative electrode potential which respectively correspond to the first charge state and the second charge state according to the relation curve of the charge state and the negative electrode potential.
According to the battery lithium precipitation detection method and device provided by the embodiment of the invention, the corresponding relation between the charge state and the negative electrode potential of the three-electrode battery in the charging process is obtained; charging the three-electrode battery by adopting a preset first current to obtain a first charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential; charging the three-electrode battery by adopting a preset second current to obtain a second charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential; determining a first negative electrode potential and a second negative electrode potential corresponding to the first state of charge and the second state of charge respectively based on the corresponding relation between the states of charge and the negative electrode potentials; wherein the negative potential is positively correlated with the logarithm of the current; and determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential, so as to determine lithium precipitation windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the charge state and the negative electrode potential. Compared with the existing battery lithium-ion detection method, the battery lithium-ion detection method and device provided by the embodiment of the invention can determine the lithium-ion windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the state of charge and the negative electrode potential, and the state of charge of the battery corresponding to each current is not required to be tested one by one, so that the efficiency and convenience of battery lithium-ion detection are improved.
Drawings
Fig. 1 is a flowchart of a method for detecting lithium precipitation of a battery according to an embodiment of the present invention;
fig. 2 is a flowchart of a method for detecting lithium precipitation of a battery according to a second embodiment of the present invention;
FIG. 3 is a schematic diagram showing the change of the potential and the state of charge of the negative electrode when the battery is charged with different currents according to the second embodiment of the present invention;
fig. 4 is a schematic diagram of a correspondence relationship between a charge state and a negative electrode potential according to a second embodiment of the present invention;
fig. 5 is a schematic diagram of a correspondence relationship between a current and a negative electrode potential according to a second embodiment of the present invention;
fig. 6 is a block diagram of a battery lithium analysis detection device according to a third embodiment of the present invention.
Detailed Description
The invention is described in further detail below with reference to the drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting thereof. It should be further noted that, for convenience of description, only some, but not all of the structures related to the present invention are shown in the drawings.
Example 1
Fig. 1 is a flowchart of a method for detecting lithium precipitation of a battery according to a first embodiment of the present invention, where the method is applicable to aspects of lithium precipitation detection of a battery, such as a three-electrode battery, and the method may be performed by a device for detecting lithium precipitation of a battery, where the device may be implemented in software and/or hardware, and where the device may be integrated into an electronic device, such as a computer, having a function of detecting lithium precipitation of a battery, and the method specifically includes the following steps:
and 110, acquiring the corresponding relation between the charge state of the three-electrode battery in the charging process and the negative electrode potential.
The three-electrode battery comprises a positive electrode, a negative electrode and a reference electrode, wherein the reference electrode is arranged between the positive electrode and the negative electrode. The three-electrode battery can be assembled in advance through an assembly process, and the specific assembly process can refer to the existing assembly method of the three-electrode battery, and is not described herein. The charge state of the three-electrode battery reflects the residual capacity of the three-electrode battery, and the voltage and the capacity of the battery are in a nonlinear relationship, so that the corresponding relationship between the charge state of the three-electrode battery and the potential of the negative electrode in the charging process is a nonlinear relationship, the three-electrode battery can be charged through a battery test system, for example, a charging power supply is arranged in the battery test system, and the charging power supply can be electrically connected with the positive electrode, the negative electrode and the reference electrode of the three-electrode battery to charge the three-electrode battery. The battery lithium separation detection device can obtain the capacity, positive and negative electrode potentials, battery voltage and other parameters of the three-electrode battery in the charging process through an input port electrically connected with the three-electrode battery, wherein the difference between the positive electrode potential and the negative electrode potential is the battery voltage, the obtained capacity is the residual capacity of the three-electrode battery, the ratio of the residual capacity to the total capacity is the value of the state of charge, and therefore the state of charge and the negative electrode potential of the three-electrode battery in the charging process can be obtained, namely the corresponding relation between the state of charge and the negative electrode potential of the three-electrode battery in the charging process is obtained.
And 120, charging the three-electrode battery by adopting a preset first current to obtain a first charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential.
The preset first current may be the minimum current in the target lithium-precipitation window, the value range of the state of charge in the target lithium-precipitation window is the preset target range, and the minimum current in the target lithium-precipitation window is the current corresponding to the maximum value of the state of charge in the target lithium-precipitation window. The battery test system can charge the three-electrode battery, in the process that the three-electrode battery adopts a preset first current charging process, the battery lithium precipitation detection device can obtain parameters such as capacity, voltage and the like of the three-electrode battery in the charging process through an input port electrically connected with the three-electrode battery, when the obtained negative electrode potential is negative electrode cutoff potential, the obtained capacity is the capacity when the obtained negative electrode potential of the three-electrode battery is negative electrode cutoff potential, and the ratio of the obtained capacity to the total capacity of the three-electrode battery is the value of the state of charge, so that the first state of charge when the negative electrode potential of the three-electrode battery is negative electrode cutoff potential can be obtained.
And 130, charging the three-electrode battery by adopting a preset second current to obtain a second charge state when the negative electrode potential of the three-electrode battery is the negative electrode cut-off potential.
The preset second current may be the maximum current in the target lithium-separating window, the value range of the state of charge in the target lithium-separating window is the preset target range, and the maximum current in the target lithium-separating window is the current corresponding to the state of charge in the target lithium-separating window when the value of the state of charge is minimum. The battery lithium separation detection device can obtain parameters such as capacity, voltage and the like of the three-electrode battery in the charging process by adopting a preset second current charging process of the three-electrode battery through an input port electrically connected with the three-electrode battery, when the obtained negative electrode potential is the negative electrode cutoff potential, the obtained capacity is the capacity when the obtained negative electrode potential of the three-electrode battery is the negative electrode cutoff potential, and the ratio of the obtained capacity to the total capacity of the three-electrode battery is the value of the state of charge, so that the second state of charge when the negative electrode potential of the three-electrode battery is the negative electrode cutoff potential can be obtained.
The specific value of the negative electrode cutoff potential may be set according to the specification and model number of the three-electrode battery and the performance parameter during actual detection, and is not limited herein.
And 140, determining a first negative electrode potential and a second negative electrode potential corresponding to the first charge state and the second charge state respectively based on the corresponding relation between the charge states and the negative electrode potentials.
And determining a first negative electrode potential and a second negative electrode potential corresponding to the first state of charge and the second state of charge respectively according to the corresponding relation curve.
And 150, determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential, so as to determine lithium precipitation windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the charge state and the negative electrode potential.
Specifically, the relationship between the negative electrode potential and the current is a linear function of the logarithm of the current, one point corresponding to the linear function in the plane rectangular coordinate system can be determined according to the preset logarithm of the first current and the first negative electrode potential, the other point corresponding to the linear function in the plane rectangular coordinate system can be determined according to the preset logarithm of the second current and the second negative electrode potential, and as a straight line can be determined between the two points, the image of the linear function in the plane rectangular coordinate system can be determined by the two points, so that the relationship between the negative electrode potential and the current is determined, and the corresponding relationship between the current and the charge state can be determined by combining the corresponding relationship between the charge state and the negative electrode potential, so that the lithium precipitation window corresponding to different currents is determined.
According to the battery lithium precipitation detection method, based on the obtained corresponding relation between the charge state and the negative electrode potential, the first negative electrode potential and the second negative electrode potential corresponding to the obtained first charge state and the second charge state are determined, and the relation between the negative electrode potential and the current is determined according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential, so that lithium precipitation windows corresponding to different currents are determined based on the relation between the negative electrode potential and the current and the corresponding relation between the charge state and the negative electrode potential. Compared with the existing battery lithium-ion detection method, the battery lithium-ion detection method provided by the embodiment can determine lithium-ion windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the state of charge and the negative electrode potential, and does not need to perform one-to-one test on the state of charge of the battery corresponding to each current, so that the efficiency and convenience of battery lithium-ion detection are improved.
Example two
Fig. 2 is a flowchart of a method for detecting lithium precipitation of a battery according to a second embodiment of the present invention, where the method is applicable to aspects of lithium precipitation detection of a battery, such as a three-electrode battery, and the method may be performed by a device for detecting lithium precipitation of a battery, where the device may be implemented in software and/or hardware, and where the device may be integrated into an electronic device having a function of detecting lithium precipitation of a battery, such as a computer, and the method specifically includes the following steps:
Specifically, the battery test system can charge the three-electrode battery with a preset multiplying power of the three-electrode battery capacity, for example, the three-electrode battery is charged with a C1 multiplying power of the three-electrode battery capacity C, and the value range of C1 is 0.01-0.1C. The battery lithium separation detection device can obtain the capacity and positive and negative electrode potentials of the three-electrode battery in the charging process, the battery voltage and other parameters of the three-electrode battery through a port electrically connected with the three-electrode battery, the difference between the positive electrode potential and the negative electrode potential is the battery voltage, the obtained capacity is the residual capacity of the three-electrode battery, the ratio of the residual capacity to the total capacity is the value of the state of charge, and therefore the state of charge and the negative electrode potential of the three-electrode battery in the charging process can be obtained, and the corresponding relation between the state of charge and the negative electrode potential of the three-electrode battery in the charging process is determined.
And 220, charging the three-electrode battery by adopting a preset first current, and obtaining a first charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential.
The method comprises the steps of presetting a first current as the minimum current in a target lithium precipitation window, presetting a value range of a state of charge in the target lithium precipitation window as a preset target range, and setting the minimum current in the target lithium precipitation window as the current corresponding to the maximum state of charge in the target lithium precipitation window. Negative electrode cut-off potential of three-electrode battery
Is 0V, eta Li+/Li 0-200mV. The battery lithium separation detection device can acquire parameters such as capacity, voltage and the like of the three-electrode battery in the charging process by adopting a preset second current charging process of the three-electrode battery through an input port electrically connected with the three-electrode battery, when the acquired negative electrode potential is the negative electrode cutoff potential, the acquired capacity is the capacity when the acquired negative electrode potential of the three-electrode battery is the negative electrode cutoff potential, and the ratio of the acquired capacity to the total capacity of the three-electrode battery is the value of the state of charge, so that the first state of charge when the negative electrode potential of the three-electrode battery is the negative electrode cutoff potential can be acquired.
And 230, charging the three-electrode battery by adopting a preset second current to obtain a second charge state when the negative electrode potential of the three-electrode battery is the negative electrode cut-off potential.
The second current is preset as the maximum current in the target lithium precipitation window. The value range of the state of charge in the target lithium precipitation window is a preset target range, and the maximum current in the target lithium precipitation window is the current corresponding to the state of charge in the target lithium precipitation window when the value of the state of charge is minimum. The battery lithium separation detection device can obtain parameters such as capacity, voltage and the like of the three-electrode battery in the charging process by adopting a preset second current charging process of the three-electrode battery through an input port electrically connected with the three-electrode battery, when the obtained negative electrode potential is the negative electrode cutoff potential, the obtained capacity is the capacity when the obtained negative electrode potential of the three-electrode battery is the negative electrode cutoff potential, and the ratio of the obtained capacity to the total capacity of the three-electrode battery is the value of the state of charge, so that the second state of charge when the negative electrode potential of the three-electrode battery is the negative electrode cutoff potential can be obtained.
Specifically, fig. 3 is a schematic diagram of the change of the potential and the state of charge of the negative electrode when the battery is charged with different currents according to the second embodiment of the present invention, as shown in fig. 3, a preset first current I is adopted 1 Charging the three-electrode battery, wherein the negative electrode potential of the three-electrode battery is negative electrode cut-off potential
When corresponding to the first charge state, a preset second current I is adopted 2 Charging the three-electrode battery, wherein the negative electrode potential of the three-electrode battery is negative electrode cutoff potential +.>
When corresponding to the second charge state, presetting a first current I 1 And presetting a second current I 2 The respective first and second states of charge are different.
And 240, drawing a relationship curve of the charge state and the negative electrode potential based on the obtained corresponding relationship of the charge state and the negative electrode potential.
Specifically, fig. 4 is a schematic diagram of a correspondence relationship between a state of charge and a negative electrode potential according to a second embodiment of the present invention, and as shown in fig. 4, in a process of SOC value from 0% to 100%, the negative electrode potential OCV of the three-electrode battery Negative pole Gradually decreasing and approaching 0V. The value of SOC of the state of charge, for example, 50%, is taken as the abscissa of a point in the rectangular plane coordinate system, the corresponding negative electrode potential is taken as the ordinate of the point, the position of the point in the rectangular plane coordinate system can be determined, then the relationship curve between the state of charge and the negative electrode potential can be drawn by a plurality of different points, the curve in fig. 4 is the relationship curve between the state of charge and the negative electrode potential, and the negative electrode potential corresponding to any state of charge and the state of charge corresponding to any negative electrode potential can be determined by the drawn curve.
Specifically, referring to fig. 4, when the battery lithium-separating detection device obtains the first state of charge and the second state of charge, the first negative electrode potential corresponding to the first state of charge and the second negative electrode potential corresponding to the second state of charge may be determined according to the relationship curve between the state of charge and the negative electrode potential as shown in fig. 4.
Wherein, the negative electrode potential OCV of the three-electrode battery Negative pole The values of a and b can be determined from the values of the two sets of current and negative potential, if a is-226.08 and b is 123.31.
Specifically, FIG. 5 is a schematic diagram showing the correspondence between current and negative potential according to the second embodiment of the present invention, when the values of a and b are determined, for example, a is-226.08 and b is 123.31, the negative potential OCV of the three-electrode battery can be determined Negative pole = 123.31lgI-226.08, i.e. the log of the current and the negative potential can be plotted as shown in fig. 5.
Step 280, determining a corresponding relation between the current and the state of charge based on the relation between the potential of the negative electrode and the current and the corresponding relation between the state of charge and the potential of the negative electrode.
Specifically, with reference to fig. 4 and fig. 5, the negative electrode potential corresponding to the current may be determined according to the correspondence shown in fig. 5, and the state of charge corresponding to the negative electrode potential may be determined according to the relationship shown in fig. 4, so that the correspondence between the current and the state of charge may be determined.
And 290, determining lithium precipitation windows corresponding to different currents according to the corresponding relation between the currents and the states of charge.
Specifically, when the current is 120A, the potential of the negative electrode corresponding to fig. 5 is 52.0mV, and the state of charge SOC corresponding to fig. 4 is 65%, and the state of charge SOC value corresponding to the current I is shown in table 1.
TABLE 1 lithium precipitation windows for different currents
| I/A | OCV/ | SOC | |
| 130 | 56.3 | 61％ | |
| 120 | 52.0 | 65％ | |
| 110 | 47.4 | 69％ | |
| 100 | 42.3 | 73％ | |
| 90 | 36.6 | 76％ | |
| 80 | 30.3 | 80％ |
According to the battery lithium precipitation detection method, based on the obtained corresponding relation between the state of charge and the negative electrode potential, a relation curve between the state of charge and the negative electrode potential is drawn, a first negative electrode potential and a second negative electrode potential corresponding to the first state of charge and the second state of charge respectively are determined according to the relation curve between the state of charge and the negative electrode potential, the relation between the negative electrode potential and the current is determined according to a preset first current, a preset second current, the first negative electrode potential and the second negative electrode potential, and the corresponding relation between the current and the state of charge is determined based on the relation between the negative electrode potential and the current and the corresponding relation between the state of charge and the negative electrode potential, so that lithium precipitation windows corresponding to different currents are determined according to the corresponding relation between the current and the state of charge. Compared with the existing battery lithium-ion detection method, the battery lithium-ion detection method provided by the embodiment can determine lithium-ion windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the state of charge and the negative electrode potential, and does not need to perform one-to-one test on the state of charge of the battery corresponding to each current, so that the efficiency and convenience of battery lithium-ion detection are improved.
Example III
Fig. 6 is a block diagram of a battery lithium-ion detection device according to a third embodiment of the present invention, where the battery lithium-ion detection device includes: a potential acquisition module 310, a first state of charge acquisition module 320, a second state of charge acquisition module 330, a potential determination module 340, and a window determination module 350; the potential obtaining module 310 is configured to obtain a corresponding relationship between a charge state of the three-electrode battery and a negative electrode potential in a charging process; the first state of charge obtaining module 320 is configured to charge the three-electrode battery with a preset first current, and obtain a first state of charge when a negative electrode potential of the three-electrode battery is a negative electrode cutoff potential; the second state of charge obtaining module 330 is configured to charge the three-electrode battery with a preset second current, and obtain a second state of charge when the negative electrode potential of the three-electrode battery is a negative electrode cutoff potential; the potential determining module 340 is configured to determine a first negative potential and a second negative potential corresponding to the first state of charge and the second state of charge, respectively, based on a correspondence between the state of charge and the negative potential; wherein the negative potential is positively correlated with the logarithm of the current; the window determining module 350 is configured to determine a relationship between the negative electrode potential and the current according to a preset first current, a preset second current, a first negative electrode potential and a second negative electrode potential, so as to determine lithium precipitation windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the state of charge and the negative electrode potential.
Optionally, the potential determining module 340 includes a curve drawing unit and a potential determining unit; the curve drawing unit is used for drawing a relation curve of the charge state and the negative electrode potential based on the obtained corresponding relation of the charge state and the negative electrode potential; the potential determining unit is used for determining a first negative electrode potential and a second negative electrode potential which respectively correspond to the first charge state and the second charge state according to a relation curve of the charge state and the negative electrode potential.
In one embodiment, window determination module 350 includes a value determination unit and a relationship determination unit; wherein the value determining unit is used for presetting a first current I 1 And a first negative electrode potential OCV Negative 1 Substituting OCV Negative pole =a+blgi, and will preset a second current I 2 And a second negative electrode potential OCV Negative 2 Substituting OCV Negative pole =a+blgi, resulting in values of a and b; the relation determining unit is used for determining the relation between the potential of the negative electrode and the current according to the values of a and b; wherein, the negative electrode potential OCV of the three-electrode battery Negative pole =a+blgi, I is current, and a and b are both coefficients.
Preferably, the window determining module 350 includes a correspondence determining unit and a window determining unit; the corresponding relation determining unit is used for determining the corresponding relation between the current and the state of charge based on the relation between the potential of the negative electrode and the current and the corresponding relation between the state of charge and the potential of the negative electrode; the window determining unit is used for determining lithium precipitation windows corresponding to different currents according to the corresponding relation between the currents and the charge states.
Preferably, the battery lithium separation detection device further comprises a corresponding relation determination module, wherein the corresponding relation determination module is used for charging the three-electrode battery with a preset multiplying power of the capacity of the three-electrode battery and determining a corresponding relation between the charge state of the three-electrode battery in the charging process and the negative electrode potential. Wherein, the three-electrode battery is charged with C1 multiplying power of the three-electrode battery capacity C, and the value range of C1 is 0.01C-0.1C.
The battery lithium-ion detection device provided by the embodiment and the battery lithium-ion detection method provided by any embodiment of the invention belong to the same invention conception, have corresponding beneficial effects, and the detailed technical details of the embodiment are not shown in the battery lithium-ion detection method provided by any embodiment of the invention.
Note that the above is only a preferred embodiment of the present invention and the technical principle applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, and that various obvious changes, rearrangements, combinations, and substitutions can be made by those skilled in the art without departing from the scope of the invention. Therefore, while the invention has been described in connection with the above embodiments, the invention is not limited to the embodiments, but may be embodied in many other equivalent forms without departing from the spirit or scope of the invention, which is set forth in the following claims.
Claims (9)
1. A method for detecting lithium precipitation of a battery, comprising:
acquiring a corresponding relation between a charge state and a negative electrode potential of the three-electrode battery in a charging process;
charging the three-electrode battery by adopting a preset first current to obtain a first charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential, wherein the preset first current is the minimum current in a target lithium precipitation window, and the minimum current in the target lithium precipitation window is the current corresponding to the maximum value of the charge state in the target lithium precipitation window;
charging the three-electrode battery by adopting a preset second current to obtain a second charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential, wherein the preset second current is the maximum current in the target lithium-precipitation window, and the maximum current in the target lithium-precipitation window is the current corresponding to the state of charge in the target lithium-precipitation window with the minimum value;
determining a first negative electrode potential and a second negative electrode potential corresponding to the first state of charge and the second state of charge respectively based on the corresponding relation between the states of charge and the negative electrode potentials;
determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential, so as to determine lithium precipitation windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the state of charge and the negative electrode potential;
the determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential comprises:
substituting the preset first current and the first negative electrode potential into OCV Negative pole =a+blgi, and substituting the preset second current and the second negative electrode potential into OCV Negative pole =a+blgi, resulting in values of a and b;
determining the relation between the potential of the negative electrode and the current according to the values of a and b; wherein, the negative electrode potential OCV of the three-electrode battery Negative pole =a+blgi, I is current, and a and b are both coefficients.
2. The method according to claim 1, wherein determining the first negative electrode potential and the second negative electrode potential, which correspond to the first state of charge and the second state of charge, respectively, based on the correspondence between the state of charge and the negative electrode potential, comprises:
drawing a relationship curve of the state of charge and the negative electrode potential based on the obtained corresponding relationship of the state of charge and the negative electrode potential;
and determining a first negative electrode potential and a second negative electrode potential respectively corresponding to the first charge state and the second charge state according to the relation curve of the charge state and the negative electrode potential.
3. The method according to claim 1, wherein determining the lithium precipitation window corresponding to different currents based on the relationship between the negative electrode potential and the current and the correspondence between the state of charge and the negative electrode potential, comprises:
determining the corresponding relation between the current and the state of charge based on the relation between the potential of the negative electrode and the current and the corresponding relation between the state of charge and the potential of the negative electrode;
and determining lithium precipitation windows corresponding to different currents according to the corresponding relation between the currents and the states of charge.
4. The method for detecting the lithium precipitation of the battery according to claim 1, wherein before obtaining the correspondence between the charge state and the negative electrode potential of the three-electrode battery in the charging process, the method comprises:
and charging the three-electrode battery with a preset multiplying power of the capacity of the three-electrode battery, and determining the corresponding relation between the charge state of the three-electrode battery in the charging process and the negative electrode potential.
5. The method according to claim 4, wherein the three-electrode battery is charged at a C1 rate of a three-electrode battery capacity C, and the value of C1 is in the range of 0.01C to 0.1C.
6. The method according to claim 1, wherein the preset first current and the preset second current are respectively a minimum current and a maximum current corresponding to a target lithium precipitation window.
7. The method for detecting lithium deposition from a battery according to claim 1, wherein a negative electrode cutoff potential Φ of the three-electrode battery Negative pole ＝E Li+/Li -η Li+/Li ，E Li+/Li Is 0V, eta Li+/Li 0-200mV.
8. A battery lithium analysis detection device, characterized by comprising:
the potential acquisition module is used for acquiring the corresponding relation between the charge state of the three-electrode battery in the charging process and the potential of the negative electrode;
the first charge state acquisition module is used for charging the three-electrode battery by adopting a preset first current to acquire a first charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential;
the second charge state acquisition module is used for charging the three-electrode battery by adopting a preset second current to acquire a second charge state when the negative electrode potential of the three-electrode battery is a negative electrode cut-off potential;
the potential determining module is used for determining a first negative electrode potential and a second negative electrode potential which correspond to the first charge state and the second charge state respectively based on the corresponding relation between the charge state and the negative electrode potential; wherein the negative potential is positively correlated with the logarithm of the current;
the window determining module is used for determining the relationship between the negative electrode potential and the current according to the preset first current, the preset second current, the first negative electrode potential and the second negative electrode potential so as to determine lithium precipitation windows corresponding to different currents based on the relationship between the negative electrode potential and the current and the corresponding relationship between the charge state and the negative electrode potential;
the window determining module comprises a numerical value determining unit and a relation determining unit; wherein the numerical value determining unit is used for substituting the preset first current and the first negative electrode potential into OCV Negative pole =a+blgi, and substituting the preset second current and the second negative electrode potential into OCV Negative pole =a+blgi, resulting in values of a and b; the relation determining unit is used for determining the relation between the potential of the negative electrode and the current according to the values of a and b; wherein, the negative electrode potential OCV of the three-electrode battery Negative pole =a+blgi, I is current, and a and b are both coefficients.
9. The battery lithium analysis detection apparatus according to claim 8, wherein the potential determination module includes:
the curve drawing unit is used for drawing a relation curve of the charge state and the negative electrode potential based on the obtained corresponding relation of the charge state and the negative electrode potential;
and the potential determining unit is used for determining a first negative electrode potential and a second negative electrode potential which respectively correspond to the first charge state and the second charge state according to the relation curve of the charge state and the negative electrode potential.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110438295.0A CN113125974B (en) | 2021-04-22 | 2021-04-22 | Method and device for detecting lithium precipitation of battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110438295.0A CN113125974B (en) | 2021-04-22 | 2021-04-22 | Method and device for detecting lithium precipitation of battery |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113125974A CN113125974A (en) | 2021-07-16 |
| CN113125974B true CN113125974B (en) | 2023-06-16 |
Family
ID=76779324
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110438295.0A Active CN113125974B (en) | 2021-04-22 | 2021-04-22 | Method and device for detecting lithium precipitation of battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113125974B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116559757B (en) * | 2023-07-04 | 2023-10-27 | 江苏天合储能有限公司 | Verification method and device for battery lithium-precipitation potential prediction accuracy and electronic equipment |
Family Cites Families (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2088842A5 (en) * | 1970-04-27 | 1972-01-07 | Manuf Accum Objets Moule | |
| IL239852A (en) * | 2015-07-08 | 2016-12-29 | Algolion Ltd | Lithium-ion battery safety monitoring |
| WO2017185181A1 (en) * | 2016-04-27 | 2017-11-02 | Charged Engineering Inc. | Systems and methods for determining state-of-charge using tafel slope |
| CN105870525B (en) * | 2016-06-20 | 2018-08-24 | 宁德新能源科技有限公司 | The method and device of battery charging |
| CN106099230B (en) * | 2016-08-09 | 2019-02-05 | 清华大学 | A kind of lithium ion battery fast charge method for preventing to analyse lithium |
| CN108761344A (en) * | 2018-06-06 | 2018-11-06 | 江苏塔菲尔新能源科技股份有限公司 | A kind of detection method and system of lithium ion battery analysis lithium |
| CN108931736B (en) * | 2018-07-13 | 2021-05-07 | 江苏塔菲尔新能源科技股份有限公司 | Method for judging lithium ion battery lithium separation critical condition |
| CN109031141B (en) * | 2018-07-13 | 2021-06-04 | 江苏塔菲尔新能源科技股份有限公司 | Lithium ion battery lithium analysis prediction method |
| CN110061315A (en) * | 2019-03-29 | 2019-07-26 | 欣旺达电动汽车电池有限公司 | A kind of lithium ion battery fast charge method |
| US11750012B2 (en) * | 2019-09-29 | 2023-09-05 | Ningde Amperex Technology Limited | Electronic device and method for charging a battery |
| CN110940920B (en) * | 2019-11-22 | 2021-10-01 | 上海理工大学 | Method for acquiring maximum charging current of lithium battery without lithium precipitation under preset SOC (state of charge) |
| CN112673266B (en) * | 2020-04-30 | 2022-01-14 | 华为技术有限公司 | Lithium analysis detection method and device, and polarization ratio acquisition method and device |
| CN112366375B (en) * | 2020-09-03 | 2022-03-18 | 万向一二三股份公司 | Quick charging method for lithium ion power battery |
| CN112180261B (en) * | 2020-09-16 | 2022-04-12 | 合肥国轩高科动力能源有限公司 | Lithium analysis detection method for lithium iron phosphate power battery |
| CN112180260A (en) * | 2020-09-24 | 2021-01-05 | 欣旺达电动汽车电池有限公司 | Battery lithium analysis window analysis method, lithium analysis detection method, device and storage medium |
-
2021
- 2021-04-22 CN CN202110438295.0A patent/CN113125974B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN113125974A (en) | 2021-07-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108445406B (en) | Power battery state of health estimation method | |
| CN103675702B (en) | A kind of method of real-time assessment cell health state | |
| CN111736085B (en) | Lithium ion battery health state estimation method based on electrochemical impedance spectrum | |
| CN110940920B (en) | Method for acquiring maximum charging current of lithium battery without lithium precipitation under preset SOC (state of charge) | |
| CN110333463B (en) | Battery cell consistency screening method and system | |
| CN108732508B (en) | Real-time estimation method for lithium ion battery capacity | |
| CN109596993B (en) | Method for detecting charge state of lithium ion battery | |
| CN112834945A (en) | Evaluation model establishing method, battery health state evaluation method and related product | |
| CN111948546A (en) | Lithium battery health degree evaluation method and system | |
| CN108445422B (en) | Battery state of charge estimation method based on polarization voltage recovery characteristics | |
| CN104076293A (en) | Quantitative analysis method for observer-based SOC estimation errors of lithium batteries | |
| CN110888057A (en) | Power lithium ion battery electrochemical parameter identification method and system | |
| CN112526352B (en) | SOH estimation method for retired lithium ion battery | |
| CN102818998A (en) | Method for detecting analyzed lithium of lithium ion power battery | |
| CN113238157A (en) | Method for screening through AI detection on retired batteries of electric vehicles | |
| CN112067999B (en) | Nondestructive acquisition system and method for open circuit potential curve of lithium ion battery anode | |
| CN109613446A (en) | A kind of aging of lithium battery detection method based on time series analysis | |
| CN110661040A (en) | Sorting method and device for retired lithium iron phosphate power battery | |
| CN103683427A (en) | Improved storage battery pack charging system and SOC (State of Charge) estimation method thereof | |
| CN113125974B (en) | Method and device for detecting lithium precipitation of battery | |
| CN109269967B (en) | Method for testing corrosion of lithium ion battery shell | |
| CN114865117A (en) | Lithium ion battery electrode lithium embedding amount detection method and device and battery management system | |
| CN114062950A (en) | Method and device for determining SOC of series-parallel battery, electronic equipment and storage medium | |
| CN102814292A (en) | Lithium ion battery consistency matching method and system | |
| CN113406520A (en) | Battery health state estimation method for real new energy automobile |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |