Battery material testing method and electronic equipment

Abstract

The invention discloses a battery material testing method and electronic equipment, and relates to the technical field of batteries. The method comprises the steps that a single-layer soft package battery is prepared, the single-layer soft package battery comprises an aluminum plastic film and a positive electrode current collector, a positive electrode material, a diaphragm, a negative electrode current collector and a negative electrode material which are wrapped in the aluminum plastic film, the positive electrode material is arranged on one side of the diaphragm, the negative electrode material is arranged on the other side of the diaphragm, and the positive electrode current collector is arranged on the side, away from the diaphragm, of the positive electrode material; the negative current collector is arranged on one side of the negative material away from the diaphragm; when the single-layer soft package battery is charged and discharged, X-rays are used for irradiating the single-layer soft package battery, and an X-ray absorption spectrum is obtained according to the X-rays penetrating through the single-layer soft package battery; the test result of the target test element is obtained according to the X-ray absorption spectrum, and the test result comprises metal element valence state change and structure change of the target test element in the charging and discharging process.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a method for testing battery materials and an electronic device. Background Art

[0002] As a high-energy density and environmentally friendly energy storage device, lithium-ion batteries are widely used in the fields of consumer electronics, electric vehicles, and energy storage systems. Their performance core depends on the structural stability and electrochemical activity of the cathode material (such as lithium cobaltate, NCM ternary lithium material, lithium iron phosphate, etc.). During the charge and discharge process of the cathode material, lithium-ion deintercalation, crystal structure phase change, and transition metal valence change will occur, and these dynamic behaviors directly affect the battery capacity, cycle life, and safety.

[0003] However, in the related art, for the test of the battery cathode material, it is difficult to realize the test of the metal element valence change and structure change of the battery cathode material in real time during the charge and discharge process. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems in the related art to some extent. For this reason, the first object of the present invention is to propose a method for testing battery materials to realize the real-time test of the metal element valence change and structure change of the battery materials during the charge and discharge process.

[0005] The second object of the present invention is to propose an electronic device.

[0006] To achieve the above object, an embodiment of the first aspect of the present invention proposes a method for testing battery materials, the method includes: preparing a single-layer soft-pack battery, wherein the single-layer soft-pack battery includes an aluminum-plastic film and a positive current collector, a positive electrode material, a separator, a negative current collector, and a negative electrode material wrapped in the aluminum-plastic film, the separator has the positive electrode material on one side and the negative electrode material on the other side, the positive current collector is arranged on the side of the positive electrode material away from the separator, and the negative current collector is arranged on the side of the negative electrode material away from the separator; when the single-layer soft-pack battery is charged and discharged, irradiate the single-layer soft-pack battery with X-rays, and obtain an X-ray absorption spectrum according to the X-rays passing through the single-layer soft-pack battery; obtain the test result of the target test element according to the X-ray absorption spectrum, wherein the test result includes the metal element valence change and structure change of the target test element in the positive electrode material during the charge and discharge process.

[0007] In addition, according to the method for testing battery materials of the embodiment of the present invention, the following additional technical features may also be provided: According to an embodiment of the present invention, the coating amount of the positive electrode material in terms of the target test element ranges from 3 to 6 mg / cm 2 .

[0008] According to an embodiment of the present invention, the material of the positive current collector is aluminum foil with a thickness less than 10 μm.

[0009] According to an embodiment of the present invention, the negative current collector is copper foil with a thickness less than 5 μm.

[0010] According to an embodiment of the present invention, the thickness of the separator is less than 25 μm.

[0011] According to an embodiment of the present invention, the thickness of the aluminum-plastic film is less than 40 μm.

[0012] According to an embodiment of the present invention, irradiating the single-layer soft-pack battery with X-rays includes: irradiating a monochromator with X-rays so that the X-rays are diffracted by the monochromator and then directed to the single-layer soft-pack battery, wherein the crystal material of the monochromator and the diffraction plane index of the monochromator are determined according to the target test element in the positive electrode material.

[0013] According to an embodiment of the present invention, obtaining an X-ray absorption spectrum based on the X-rays transmitted through the single-layer soft-pack battery includes: obtaining an X-ray transmission intensity curve based on the X-rays transmitted through the single-layer soft-pack battery; and obtaining an X-ray absorption spectrum based on the X-ray transmission intensity curve and a reference intensity curve.

[0014] According to an embodiment of the present invention, the method for determining the crystal material and the diffraction plane index includes: determining the X-ray photon energy according to the target test element; and determining the crystal material and the diffraction plane index according to the X-ray photon energy.

[0015] An embodiment of the second aspect of the present invention provides an electronic device, including a memory, a processor, and a computer program stored on the memory and running on the processor. When the computer program is executed by the processor, the above battery material testing method is implemented.

[0016] A battery material testing method and an electronic device according to an embodiment of the present invention. The method includes: preparing a single-layer soft-pack battery, where the single-layer soft-pack battery includes an aluminum-plastic film and a positive current collector, a positive electrode material, a separator, a negative current collector, and a negative electrode material wrapped in the aluminum-plastic film. The separator has the positive electrode material on one side and the negative electrode material on the other side. The positive current collector is disposed on the side of the positive electrode material away from the separator, and the negative current collector is disposed on the side of the negative electrode material away from the separator. When the single-layer soft-pack battery is charged and discharged, the single-layer soft-pack battery is irradiated with X-rays, and an X-ray absorption spectrum is obtained based on the X-rays passing through the single-layer soft-pack battery. A test result of a target test element is obtained based on the X-ray absorption spectrum, where the test result includes the change in the valence state of the metal element and the structural change of the target test element during the charge and discharge process. Thus, by preparing a single-layer soft-pack battery with a special structure and testing the single-layer soft-pack battery with the special structure, it is possible to simultaneously test the change in the valence state of the metal element and the structural change of the target test element in real time during the charge and discharge process.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a flowchart of the battery material testing method according to an embodiment of the present invention; Figure 2 is a schematic structural diagram of the single-layer soft-pack battery according to an embodiment of the present invention; Figure 3 is a schematic diagram of the battery material testing according to an embodiment of the present invention; Figure 4 is a schematic structural diagram of the soft-pack battery clamp according to an embodiment of the present invention; Figure 5 is a flowchart of the battery material testing method according to an example of the present invention; Figure 6 is a schematic diagram of the result of the battery material testing method according to an example of the present invention; Figure 7 is a schematic diagram of the result of the battery material testing method according to another example of the present invention; Figure 8 is a schematic diagram of the result of the battery material testing method according to yet another example of the present invention; Figure 9 is a structural block diagram of the electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The battery material testing method and electronic device according to the embodiments of the present invention will be described below with reference to the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described with reference to the accompanying drawings are exemplary and should not be construed as limiting the present invention.

[0020] Figure 1 is a flowchart of the battery material testing method according to the embodiments of the present invention.

[0021] As Figure 1 shown, the battery material testing method includes: S11, preparing a single-layer soft-pack battery, where the single-layer soft-pack battery includes an aluminum-plastic film and a positive current collector, a positive electrode material, a separator, a negative current collector, and a negative electrode material wrapped in the aluminum-plastic film. The positive electrode material is disposed on one side of the separator, the negative electrode material is disposed on the other side of the separator, the positive current collector is disposed on the side of the positive electrode material away from the separator, and the negative current collector is disposed on the side of the negative electrode material away from the separator.

[0022] Specifically, in order to support the simultaneous testing of the valence state change and structural change of metal elements in the battery positive electrode material, a single-layer soft-pack battery is designed. The layered structure of this single-layer soft-pack battery is shown in Figure 2 , including five layers, namely a positive current collector 21, a positive electrode material 22, a separator 31, a negative electrode material 42, and a negative current collector 41. And the specific layered structure of this single-layer soft-pack battery is in the order of the positive current collector 21, the positive electrode material 22, the separator 31, the negative electrode material 42, and the negative current collector 41. Moreover, an aluminum-plastic film 11 is also provided, and the above positive current collector 21, positive electrode material 22, separator 31, negative current collector 41, and negative electrode material 42 are wrapped by this aluminum-plastic film 11.

[0023] The above positive electrode material 22 can be lithium iron phosphate, lithium iron manganese phosphate, lithium cobaltate, lithium nickel cobalt manganate, etc., and the above target test elements are elements such as manganese, iron, nickel, and cobalt in the positive electrode material 22.

[0024] The thicknesses of the above positive current collector 21, negative current collector 41, negative electrode material 42, separator 31, and aluminum-plastic film 11 should preferably use the thinnest materials that do not affect the functions of the soft-pack battery.

[0025] Thus, by setting the single-layer soft-pack battery with the above special structure, a battery that can support the simultaneous testing of the valence state change and structural change of the target test elements in the positive electrode material 22 in the single-layer soft-pack battery is obtained.

[0026] S12, when the single-layer soft-pack battery is charged and discharged, irradiate the single-layer soft-pack battery with X-rays, and obtain an X-ray absorption spectrum according to the X-rays passing through the single-layer soft-pack battery.

[0027] Specifically, after preparing the above-mentioned single-layer soft-pack battery with a special structure, irradiate the single-layer soft-pack battery with a special structure using X-rays to obtain X-rays that penetrate the single-layer soft-pack battery, and then an X-ray absorption spectrum can be obtained based on the X-rays that penetrate the single-layer soft-pack battery.

[0028] S13. Obtain the test results of the target test element in the positive electrode material according to the X-ray absorption spectrum, where the test results include the valence state change and structural change of the metal element of the target test element during charge and discharge.

[0029] Thus, it is possible to test the valence state change and structural change of the metal element of the battery material.

[0030] In some embodiments of the present invention, the coating amount of the positive electrode material 22 is determined according to the elemental composition of the positive electrode material 22 and the target test element.

[0031] In some embodiments of the present invention, the coating amount of the positive electrode material 22 in terms of the target test element ranges from 3 to 6 mg / cm 2 . That is, the coating amount of the positive electrode material 22 is based on the elemental mass, rather than the mass of the positive electrode material 22.

[0032] In some embodiments of the present invention, the material of the positive electrode current collector 21 is aluminum foil with a thickness less than 10 μm.

[0033] In some embodiments of the present invention, the negative electrode current collector 41 is copper foil with a thickness less than 5 μm.

[0034] In some embodiments of the present invention, the thickness of the separator 31 is less than 25 μm. The separator 31 preferably uses organic polymer materials such as polypropylene and polyethylene.

[0035] In some embodiments of the present invention, the thickness of the aluminum-plastic film 11 is less than 40 μm.

[0036] In some embodiments of the present invention, the negative electrode material 42 uses a carbon-based material or lithium metal. The negative electrode material 42 cannot use lithium titanate or other alloy materials.

[0037] It should be noted that for the above-mentioned single-layer soft-pack battery with a special structure, its special structure also includes that the coating amount of the positive electrode material 22 in terms of the target test element ranges from 3 to 6 mg / cm 2That is, the coating amount of the positive electrode material 22 is based on the elemental mass, rather than the mass of the positive electrode material 22. The material of the positive electrode current collector 21 is aluminum foil with a thickness less than 10 μm. The negative electrode current collector 41 is copper foil with a thickness less than 5 μm. The thickness of the separator 31 is less than 25 μm. The separator 31 preferably uses organic polymer materials such as polypropylene and polyethylene. The thickness of the aluminum-plastic film 11 is less than 40 μm. The negative electrode material 42 uses carbon-based materials or lithium metal.

[0038] In some embodiments of the present invention, irradiating a single-layer soft-pack battery with X-rays includes: irradiating a monochromator with X-rays so that the X-rays are diffracted by the monochromator and then directed towards the single-layer soft-pack battery, wherein the crystal material of the monochromator and the diffraction plane index of the monochromator are determined according to the target test element in the positive electrode material 22.

[0039] In some embodiments of the present invention, obtaining an X-ray absorption spectrum based on the X-rays transmitted through the single-layer soft-pack battery includes: obtaining an X-ray transmission intensity curve based on the X-rays transmitted through the single-layer soft-pack battery; obtaining an X-ray absorption spectrum based on the X-ray transmission intensity curve and a reference intensity curve.

[0040] Specifically, when obtaining the X-ray transmission intensity curve of the single-layer soft-pack battery based on the X-rays transmitted through the single-layer soft-pack battery, it is also necessary to know the reference intensity curve, and obtain the X-ray absorption spectrum of the single-layer soft-pack battery based on the X-ray transmission intensity curve and the reference intensity curve.

[0041] To obtain the above reference intensity curve, the single-layer soft-pack battery can be irradiated with X-rays again. The difference is that the single-layer soft-pack battery is removed, that is, the X-rays do not penetrate the single-layer soft-pack battery and directly reach the X-ray detection position. Then, the reference intensity curve can be obtained based on the X-rays reaching the X-ray detection position. This reference intensity curve can reflect the influence of the environment on the X-rays.

[0042] Thus, through the reference intensity curve, the influence of the environment on the battery material test can be excluded, thereby achieving accurate battery material testing.

[0043] In some embodiments of the present invention, the method for determining the crystal material and the diffraction plane index includes: determining the X-ray photon energy according to the target test element; determining the crystal material and the diffraction plane index according to the X-ray photon energy.

[0044] Specifically, after the X-rays depart from the light source and reach the monochromator, they are diffracted and then reach the single-layer soft-pack battery. The X-ray diffraction process satisfies Bragg's equation: .

[0045] Among them, is the spacing of the crystal diffraction plane, is the Bragg angle, is the diffraction order, is the X-ray wavelength. Also, since the X-ray absorption fine structure spectrometer is an energy spectrum scanner, expressing in terms of X-ray energy is more convenient for use, that is: .

[0046] To ensure the diffraction efficiency, the diffraction order is set to 1, and based on this, the Bragg equation is rewritten as: .

[0047] Where is the Planck constant, 4.1356676969×10^-15 eV·s, is the speed of light in vacuum, 299792458 m / s, and E is the X-ray photon energy.

[0048] Therefore, after determining the target test element, the X-ray photon energy E can be determined according to the target test element, and then the Bragg angle and the lattice plane spacing of the crystal can be matched according to the X-ray photon energy E. Thus, according to the lattice plane spacing of the crystal, the specific crystal material and diffraction plane index used can be matched.

[0049] For the monochromator used to diffract X-rays, the material is usually single-crystalline silicon or single-crystalline germanium. The relationship between the lattice plane spacing d of the crystal and the diffraction plane index of single-crystalline silicon or single-crystalline germanium is: .

[0050] Where is the lattice constant of single-crystalline silicon or single-crystalline germanium, which are 5.431 Å and 5.658 Å respectively, and H, K, L are the diffraction plane indices of single-crystalline silicon or single-crystalline germanium. Among them, since single-crystalline silicon or single-crystalline germanium has a diamond-type structure, when the values of all three are all odd, or all even and is divisible by 4, the corresponding crystal lattice plane can achieve X-ray diffraction.

[0051] The following is illustrated with a specific embodiment.

[0052] In this specific embodiment, referring to Figure 3 , in Figure 3Among them, 10 is an X-ray absorption fine structure spectrometer, 16 is an X-ray source, 12 is a monochromator, 13 is a silicon drift detector, 14 is a slit, 15 is a single-layer soft-pack battery, 20 is a battery performance detection system, and 30 is a computer. A is a Rowland circle. The centers of the above-mentioned X-ray source 11 and monochromator 12 and the slit 14 need to be located on the Rowland circle A. B is the incident angle of the light emitted by the X-ray source 11 on the center of the monochromator, and the incident angle B = 90° - Bragg angle. The coating amount of the positive electrode material 22 in terms of the target test element ranges from 3 to 6 mg / cm 2 . That is, the coating amount of the positive electrode material 22 is in terms of the element mass, rather than the mass of the positive electrode material 22. The material of the positive electrode current collector 21 is aluminum foil with a thickness less than 10 μm. The negative electrode current collector 41 is copper foil with a thickness less than 5 μm. The thickness of the separator 31 is less than 25 μm. The separator 31 should preferably use organic polymer materials such as polypropylene and polyethylene. The thickness of the aluminum-plastic film 11 is less than 40 μm. The negative electrode material 42 uses a carbon-based material or lithium metal.

[0053] The above-mentioned computer 30 is connected to the X-ray absorption fine structure spectrometer 10, specifically, it can be connected to the silicon drift detector 13 in the X-ray absorption fine structure spectrometer 10.

[0054] The above-mentioned single-layer soft-pack battery is fixed by a soft-pack battery clamp. The soft-pack battery clamp can be referred to Figure 4 , including a soft-pack battery tab 17, a fixture backplane 23, a fixture cover plate 24, and a light passing hole C.

[0055] The X-ray absorption fine structure spectrometer 10 has a radiation-proof leakage housing. Therefore, the electrode connection wires of the battery performance detection system 20 need to be pre-connected to the single-layer soft-pack battery 15 through the through-board interface of the housing of the X-ray absorption fine structure spectrometer 10. The computer 30 can be connected to and control the X-ray absorption fine structure spectrometer 10 and the battery performance detection system 20 through communication cables.

[0056] Place the single-layer soft-pack battery 15 between the fixture backplane 23 and the fixture cover plate 24 of the soft-pack battery clamp, and then use screws to fasten the backplane and the cover plate. In addition, it is necessary to ensure that the inner layer of the soft-pack battery corresponding to the position of the light passing hole C contains the positive electrode current collector 21 (including the positive electrode material 22), the separator 31, and the negative electrode current collector 41 (including the negative electrode material 42) at the same time, so as to ensure that the soft-pack battery in the test area can be in a normal charge and discharge state. After installation, place the soft-pack battery fixture at Figure 3 the position of the single-layer soft-pack battery 15 shown, and then connect the electrode connection wires of the battery performance detection system 20 to the soft-pack battery tab 17.

[0057] In the in-situ test of the single-layer soft-pack battery 15, the battery performance detection system 20 is used to implement functions such as charging and discharging for the single-layer soft-pack battery 15, and can collect basic information of the single-layer soft-pack battery 15 such as voltage, current, and resistance in real time.

[0058] In the in-situ test of the single-layer soft-pack battery 15, the X-ray absorption fine structure spectrometer 10 is used to measure the K-edge X-ray absorption spectra of the target test metals in the positive electrode material 22 of the single-layer soft-pack battery 15, usually manganese, iron, cobalt, and nickel, and the corresponding energy range of the X-ray is 6500 - 9000 eV. To smoothly perform the in-situ test, the X-ray absorption fine structure spectrometer 10 has the following requirements: It is usually a focusing-type bent-crystal spectrometer with a scanning mechanism, and a monochromator 12 is applied. In this specific embodiment, a bent-crystal monochromator 12 is applied. The bent-crystal monochromator 12 is an optical component whose crystal diffraction surface is bent into a spherical surface with a curvature radius of 2R. The spherical vertex of the bent-crystal monochromator 12 is tangent to the Rowland circle A with a radius of R. The light source is located on the Rowland circle A, and the X-ray spot is diffracted by the bent-crystal monochromator 12 and refocused on the Rowland circle A.

[0059] To measure the K-edge absorption spectra of manganese, iron, cobalt, and nickel, the spectrometer is equipped with different bent-crystal monochromators 12 to cover the energy test ranges of common target test elements. That is to say, the crystal material and diffraction plane index of the monochromator 12 are determined according to the target test element.

[0060] Energy resolution In the XANES (X-ray Absorption Near-Edge Structure) test range, it should be greater than 4000, and in the EXAFS (Extended X-ray Absorption Fine Structure) test range, it should be greater than 1000.

[0061] In the tested energy range, the monochromatized X-ray photon flux reaching the single-layer soft-pack battery 15 should be greater than 5×10^5 photons / s.

[0062] The parameters of the silicon drift detector 13 should be set so that when the input count rate is 100 kcps, the dead time is less than 10%.

[0063] It is required to have a helium gas cavity to increase the X-ray transmission efficiency, and it is required that the transmission distance of the X-ray in the helium gas is not less than the radius R of the Rowland circle A to ensure the normal test of manganese and iron.

[0064] It can realize continuous cyclic testing of the sample, and set the time, energy range, and energy interval for a single test of the sample.

[0065] Set parameters such as the charge-discharge process and the number of cycles for the single-layer soft-pack battery 15 in the battery performance detection system 20, and formulate an operation plan for the battery. Then, set the target test element in the X-ray absorption fine structure spectrometer 10. For example, if focusing on the iron element in the battery cathode material 22, assemble the bent crystal monochromator 12, set the test parameters, and set the test time and the number of tests that match the battery operation plan. Subsequently, execute the battery operation plan and the X-ray absorption spectrum test plan simultaneously.

[0066] For different target test elements, the corresponding K-edge energy threshold, energy range, X-ray tube power, and test time need to be set.

[0067] After the test plan is completed, the charge-discharge curve of the single-layer soft-pack battery 15 and the X-ray photon flux-scanning energy curve of m single-layer soft-pack batteries 15 will be obtained in the computer 30, and this X-ray photon flux-scanning energy curve will be used as the X-ray transmission intensity curve. The X-ray transmission intensity curve of the m-th single-layer soft-pack battery 15 is denoted as .

[0068] Take out the single-layer soft-pack battery 15 from the fixture of the single-layer soft-pack battery 15, then keep the fixture of the single-layer soft-pack battery 15 in the X-ray absorption fine structure spectrometer 10, and then place different attenuation sheets at the light-passing port of the fixture to attenuate the X-ray photon flux to about 1 / 10 to 1 / 20 of the original, ensuring that the signal intensity collected by the silicon drift detector 13 is between 30 and 90 kcps.

[0069] After that, the single-layer soft-pack battery 15 needs to be removed, and the attenuation sheet is set, and the attenuation sheet can be made of aluminum foil. That is to say, after removing the single-layer soft-pack battery 15, for different target detection elements, the corresponding peak signal intensity, attenuation sheet thickness, and transmittance, as well as the K-edge energy threshold, energy range, and X-ray tube power, need to be set. Then, execute the same X-ray absorption spectrum test parameters as the above steps to obtain the X-ray photon flux-scanning energy curve under the condition of no single-layer soft-pack battery 15, denoted as I0. The X-ray photon flux-scanning energy curve under the condition of no single-layer soft-pack battery 15 is the reference intensity curve.

[0070] According to Lambert-Beer's law, obtain m X-ray absorption spectrum curves during the charge-discharge process of the single-layer soft-pack battery 15: , is the m-th X-ray absorption spectrum curve.

[0071] Then, perform operations such as energy correction, normalization, background subtraction, and Fourier transform on the X-ray absorption spectrum curve in data processing software to obtain the normalized X-ray absorption spectrum curve and the R-space radial distribution function curve, which can identify the valence state changes and local structure changes of the target test element in the cathode material of the battery during charge and discharge.

[0072] Specific working procedures can be referred to Figure 5 for examples, including the following steps: S01, fabricate a single-layer soft-pack battery that meets the test conditions.

[0073] S02, prepare the X-ray absorption fine structure spectrometer, battery performance detection system, and computer properly connected as in-situ test equipment.

[0074] Specifically, the connection relationship of the X-ray absorption fine structure spectrometer 10, battery performance detection system 20, and computer 30 can be referred to Figure 2 .

[0075] S03, place the fabricated single-layer soft-pack battery properly in the test position of the X-ray absorption fine structure spectrometer, and then connect the tabs of the soft-pack battery to the battery performance detection system.

[0076] S04, use the battery performance detection system to set the charge and discharge settings and parameters of the soft-pack battery.

[0077] S05, confirm whether the X-ray absorption fine structure spectrometer meets the test usage requirements.

[0078] S06, use the X-ray absorption fine structure spectrometer to set the test parameters of the target test element, ensure that the test plan matches the charge and discharge process, and then perform the charge and discharge and X-ray absorption spectrum test calculations simultaneously.

[0079] S07, after the test, obtain the charge and discharge curve and the It curve of the target test element of the soft-pack battery.

[0080] This It curve is the above-mentioned X-ray transmission intensity curve.

[0081] S08, take out the soft-pack battery, perform the X-ray absorption spectrum test again, and obtain the I0 curve of the target test element when there is no soft-pack battery in the optical path.

[0082] This I0 curve is the above-mentioned reference intensity curve.

[0083] S09, use the It curve and I0 curve to obtain the X-ray absorption spectrum of the single-layer soft-pack battery during charge and discharge, and analyze the valence state changes and local structure changes of the target test element during the charge and discharge of the battery.

[0084] The lithium iron manganese phosphate cathode material 22 was measured according to the above steps, and the Figure 6 charge-discharge curves of the single-layer soft-pack battery 15 made of the lithium iron manganese phosphate cathode material 22 during charge and discharge, Figure 7 X-ray absorption spectrum curve of manganese shown in Figure 8 and the R-space radial distribution function curve shown in

[0085] were obtained. Among them, Figure 6 the numbers 1 to 15 in represent the sequence numbers of the X-ray absorption spectrum curves synchronously tested during the charge-discharge process. 2 to 8 are related to the charging process, and 9 to 14 are related to the discharging process, showing the voltage of the single-layer soft-pack battery 15 during the charge-discharge process.

[0086] Figure 7 is the X-ray absorption spectrum of the single-layer soft-pack battery 15 using the lithium iron manganese phosphate cathode material 22 during multiple experiments.

[0087] Figure 8 is the R-space radial distribution function curve obtained from the X-ray absorption spectrum shown in Figure 7 . In Figure 8 , the abscissa of this curve is the radial distance between atoms, and the ordinate is the radial distribution function value.

[0088] Based on this, it can be identified that there is a phenomenon of stage oxidation of Mn2+ during the charging process. At the same time, the structural disorder around the Mn atom decreases and the oxygen vacancies increase during the charging process. It can be seen that through the single-layer soft-pack battery 15 with the above special structure, it is possible to realize a battery that can simultaneously test the valence state change and structural change of the target test element in the cathode material 22 of the single-layer soft-pack battery 15. Moreover, by setting the crystal plane spacing and bending radius of the monochromator 12 according to the target test element, more accurate testing can be achieved.

[0089] In summary, the battery material testing method according to the embodiments of the present invention includes: preparing a single-layer soft-pack battery, where the single-layer soft-pack battery includes an aluminum-plastic film and a positive current collector, a positive electrode material, a separator, a negative current collector, and a negative electrode material wrapped in the aluminum-plastic film. The positive electrode material is disposed on one side of the separator, the negative electrode material is disposed on the other side of the separator, the positive current collector is disposed on the side of the positive electrode material away from the separator, and the negative current collector is disposed on the side of the negative electrode material away from the separator; when the single-layer soft-pack battery is charged and discharged, the single-layer soft-pack battery is irradiated with X-rays, and an X-ray absorption spectrum is obtained based on the X-rays passing through the single-layer soft-pack battery; a test result of a target test element is obtained based on the X-ray absorption spectrum, where the test result includes the change in the valence state and structure of the metal element of the target test element during the charge and discharge process. Thus, by preparing a single-layer soft-pack battery with a special structure and testing the single-layer soft-pack battery with the special structure, it is possible to simultaneously test the change in the valence state and structure of the metal element of the target test element. Moreover, by determining the crystal material and diffraction plane index of the monochromator based on the target test element in the positive electrode material, an accurate selection of the monochromator can be achieved, thereby improving the test accuracy. Moreover, by setting the diffraction order to 1, the diffraction efficiency is ensured.

[0090] Further, the present invention proposes an electronic device.

[0091] Figure 9 It is a structural block diagram of the electronic device according to the embodiments of the present invention.

[0092] As Figure 9 shown, the electronic device 500 includes: a processor 501 and a memory 503. Among them, the processor 501 and the memory 503 are connected, such as connected through a bus 502. Optionally, the electronic device 500 may further include a transceiver 504. It should be noted that in practical applications, the transceiver 504 is not limited to one, and the structure of the electronic device 500 does not constitute a limitation to the embodiments of the present invention.

[0093] The processor 501 can be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute various exemplary logical blocks, modules, and circuits described in connection with the disclosure of the present invention. The processor 501 can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0094] The bus 502 can include a path for transmitting information between the above components. The bus 502 can be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The bus 502 can be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 9 only a thick line is shown herein, but it does not mean that there is only one bus or one type of bus.

[0095] The memory 503 is used to store a computer program corresponding to the battery material testing method of the foregoing embodiments of the present invention, and this computer program is controlled and executed by the processor 501. The processor 501 is used to execute the computer program stored in the memory 503 to implement the content shown in the foregoing method embodiments.

[0096] Among them, Figure 9 the illustrated electronic device 500 is only an example and should not impose any limitation on the functions and usage scope of the embodiments of the present invention.

[0097] The electronic device of the embodiments of the present invention implements the battery material testing method of the foregoing embodiments. By preparing a single-layer soft-pack battery with a special structure and testing the single-layer soft-pack battery with the special structure, it is possible to simultaneously test the valence state change and structure change of the metal elements of the target test elements.

[0098] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein can be considered as a definite sequence list of executable instructions for implementing logical functions, which can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in combination with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or other appropriate processing as necessary, and then stored in a computer memory.

[0099] It should be understood that various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, any one or a combination of the following techniques known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0100] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0101] In the description of this specification, the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as a limitation on the present invention.

[0102] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0103] In the description of this specification, unless otherwise stated, the terms "mounted", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0104] In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0105] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as a limitation on the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A battery material testing method, characterized in that: The method comprises: Prepare a single-layer soft-pack battery, wherein the single-layer soft-pack battery comprises an aluminum-plastic film and a positive electrode current collector, a positive electrode material, a separator, a negative electrode current collector, and a negative electrode material wrapped in the aluminum-plastic film, the positive electrode material is arranged on one side of the separator, the negative electrode material is arranged on the other side of the separator, the positive electrode current collector is arranged on the side of the positive electrode material away from the separator, and the negative electrode current collector is arranged on the side of the negative electrode material away from the separator; When the single-layer soft-pack battery is charged and discharged, the single-layer soft-pack battery is irradiated with X-rays, and an X-ray absorption spectrum is obtained according to the X-rays that pass through the single-layer soft-pack battery; A test result of a target test element in the positive electrode material is obtained according to the X-ray absorption spectrum, wherein the test result includes a metal element valence change and a structural change of the target test element during the charge and discharge process.

2. The battery material testing method according to claim 1, characterized in that: The coating amount of the target test element in the positive electrode material ranges from 3 to 6 mg / cm 2 .

3. The battery material testing method according to claim 1, characterized in that: The positive electrode current collector is made of aluminum foil with a thickness of less than 10 μm.

4. The battery material testing method according to claim 1, characterized in that: The negative electrode current collector is copper foil with a thickness of less than 5 μm.

5. The battery material testing method according to claim 1, characterized in that: The thickness of the separator is less than 25 μm.

6. The battery material testing method according to claim 1, characterized in that: The thickness of the aluminum-plastic film is less than 40 μm.

7. The battery material testing method according to claim 1, characterized in that: The method of irradiating the single-layer soft-pack battery with X-rays comprises: A monochromator is irradiated with X-rays so that the X-rays are directed toward the single-layer soft-pack battery after being diffracted by the monochromator, wherein the crystal material of the monochromator and the diffraction surface index of the monochromator are determined according to the target test element in the positive electrode material.

8. The battery material testing method according to claim 1, characterized in that: The method of obtaining an X-ray absorption spectrum according to X-rays transmitted through the single-layer soft-pack battery comprises: Obtaining an X-ray transmission intensity curve according to the X-rays transmitted through the single-layer soft-pack battery; An X-ray absorption spectrum is obtained according to the X-ray transmission intensity curve and the reference intensity curve.

9. The battery material testing method according to claim 7, characterized in that: The method for determining the crystal material and the diffraction surface index comprises: determining X-ray photon energy according to the target test element; The crystal material and the diffraction surface index are determined according to the X-ray photon energy.

10. An electronic device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory and running on the processor, wherein when the computer program is executed by the processor, the battery material testing method according to any one of claims 1 to 9 is implemented.

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