CN112909368A - Battery cell for three-electrode test and test method thereof - Google Patents
Battery cell for three-electrode test and test method thereof Download PDFInfo
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- 238000010998 test method Methods 0.000 title claims description 8
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- 238000004804 winding Methods 0.000 claims abstract description 45
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- 229910052744 lithium Inorganic materials 0.000 claims description 29
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 claims description 24
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 17
- 239000011149 active material Substances 0.000 claims description 17
- 229910002804 graphite Inorganic materials 0.000 claims description 16
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- GELKBWJHTRAYNV-UHFFFAOYSA-K lithium iron phosphate Chemical compound [Li+].[Fe+2].[O-]P([O-])([O-])=O GELKBWJHTRAYNV-UHFFFAOYSA-K 0.000 claims description 8
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- 238000000034 method Methods 0.000 abstract description 3
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- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 3
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- HFCVPDYCRZVZDF-UHFFFAOYSA-N [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O Chemical compound [Li+].[Co+2].[Ni+2].[O-][Mn]([O-])(=O)=O HFCVPDYCRZVZDF-UHFFFAOYSA-N 0.000 description 2
- DPXJVFZANSGRMM-UHFFFAOYSA-N acetic acid;2,3,4,5,6-pentahydroxyhexanal;sodium Chemical compound [Na].CC(O)=O.OCC(O)C(O)C(O)C(O)C=O DPXJVFZANSGRMM-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
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- QHGJSLXSVXVKHZ-UHFFFAOYSA-N dilithium;dioxido(dioxo)manganese Chemical compound [Li+].[Li+].[O-][Mn]([O-])(=O)=O QHGJSLXSVXVKHZ-UHFFFAOYSA-N 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
- H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/403—Cells and electrode assemblies
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/052—Li-accumulators
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M10/00—Secondary cells; Manufacture thereof
- H01M10/05—Accumulators with non-aqueous electrolyte
- H01M10/058—Construction or manufacture
- H01M10/0587—Construction or manufacture of accumulators having only wound construction elements, i.e. wound positive electrodes, wound negative electrodes and wound separators
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- 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
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- 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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
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Abstract
The invention discloses a battery cell for three-electrode testing, which is formed by packaging a basic winding core and a third electrode unit together through an aluminum-plastic packaging film; after the third electrode unit is activated, the reference electrode lug led out from the third electrode unit has an obvious potential platform, and the reference electrode lug led out from the third electrode unit can be used as a reference electrode. The electric core for three-electrode testing adopts one tab of the third electrode unit with a single-layer structure as the third electrode, and the third electrode can keep the stability of the electric potential in the testing process. The electric core adopts the positive and negative electrode active material electrodes containing good charge and discharge potential platforms as reference electrodes in a three-electrode test system, can bear certain current in a proper charge state and maintain the stability of potential in continuous test, and can well monitor the potential change condition of the positive electrode and the negative electrode in the basic roll core in real time when the current passes.
Description
Technical Field
The invention relates to the field of lithium ion batteries, in particular to a battery cell for three-electrode testing and a testing method thereof.
Background
Since the introduction of the lithium ion battery by the company SONY of japan in 1990, the lithium ion battery has been widely used in the fields of digital code, energy storage, new energy vehicles, and the like due to its advantages in energy density, power density, cycle life, and safety, and the market scale has rapidly expanded, and has become the most widely used storage battery system.
A conventional lithium battery is composed of a positive electrode and a negative electrode, and the battery voltage is the difference between the positive electrode potential and the negative electrode potential. The voltage change of the lithium battery under the condition of passing current is tested, the potential difference of the positive electrode and the negative electrode when the point is taken is obtained, and the real-time potential change condition of the positive electrode and the negative electrode cannot be obtained. In order to monitor the real-time change of the positive electrode and the negative electrode potential of the lithium battery under the condition of passing current so as to deepen the understanding of the performance characteristics and the performance change of the lithium battery, a third electrode needs to be introduced into the lithium battery.
Currently, common third electrodes are lithium metal sheets and copper wires. The lithium metal sheet needs to lead out a tab, and is inconvenient to manufacture. The copper wire used as the third electrode is thin, and needs to be short-circuited with a charged negative electrode before use so as to plate a layer of lithium on the surface of the copper wire. When the lithium-plated copper wire used as the third electrode is connected to a circuit to monitor the potentials of the positive electrode and the negative electrode, the lithium-plated copper wire is thin, the lithium plating amount is limited, lithium is consumed in the test process, and even the complete copper surface is completely consumed and exposed, so that the measured potential data is inaccurate. It can be seen that it is critical that the third electrode maintain a stable potential state during testing.
After the existing third electrode is used for a period of time, unexpected errors can be generated along with the consumption of surface lithium, the consumption of the lithium cannot be detected by an effective means before the test, and the potential is unstable and is not suitable for long-term continuous operation.
Disclosure of Invention
In order to solve the problems, the invention aims to provide the electric core for the three-electrode test and the test method thereof, wherein the electric core is stable in potential platform and can be accurately monitored in real time.
In order to realize the technical purpose, the scheme of the invention is as follows: a battery core for three-electrode testing comprises a basic winding core, an isolation film and a third electrode unit, wherein the basic winding core and the third electrode unit are packaged together through an aluminum-plastic packaging film;
after the third electrode unit is activated, one electrode with an obvious charge-discharge platform in the third electrode unit is selected as a third electrode, and the third electrode can be used as a reference battery after the charge state is adjusted.
Preferably, the basic winding core comprises a positive plate and a negative plate, a diaphragm is arranged between the positive plate and the negative plate, a positive tab is welded on the positive plate, a negative tab is welded on the negative plate, and the positive tab and the negative tab are led out from the top end of the aluminum plastic packaging film;
the isolating film is of a sheet structure and is arranged between the basic roll core and the third electrode unit.
Preferably, the third electrode unit is formed by combining a single-layer positive electrode coated on one side, a single-layer negative electrode coated on one side and a composite film, wherein the composite film is positioned between the coating surfaces of the single-layer positive electrode and the single-layer negative electrode;
the single-layer positive electrode is provided with a first tab, the single-layer negative electrode is provided with a second tab, and the first tab and the second tab are led out from the top end, the bottom end or the side end of the aluminum-plastic packaging film.
Preferably, the basic winding core comprises at least one layer of positive plate and one layer of negative plate, and the basic winding core is formed by processing the positive plate, the negative plate and the diaphragm in a winding or laminating mode.
Preferably, the separator has a thickness of not less than 25 μm and a porosity of not more than 40%.
A preparation method of a battery cell for three-electrode testing comprises the following specific steps of:
s1, preparing a basic core: manufacturing a basic winding core according to the steps of slurry mixing, coating, rolling, slitting, tab setting and winding core assembling;
s2, preparing a third electrode unit: manufacturing a third electrode unit according to the steps of slurry mixing, coating, rolling, slitting, tab setting and laminating, wherein the single-layer positive electrode and the single-layer negative electrode are of single-side coating structures, and the back surfaces of the single-layer positive electrode and the single-layer negative electrode are not coated with adhesive paper;
s3, assembling into a shell: sequentially placing the basic winding core, the isolation film and the third electrode unit into a punched aluminum-plastic packaging film, adjusting the position directions of a positive lug and a negative lug of the basic winding core and the first lug and the second lug of the third electrode unit to avoid direct superposition contact, then packaging the aluminum-plastic packaging film, reserving an opening at one side, and then placing the packaging film into a vacuum oven for dewatering to obtain a dry cell;
s4, injection: and after the moisture of the dry battery cell in the vacuum oven is qualified, performing liquid injection and sealing operation to obtain the battery cell for the three-electrode test.
Preferably, at least one of the single-layer positive electrode and the single-layer negative electrode of the third electrode unit is coated with an electrode active material having an obvious charge-discharge plateau potential, and the electrode active material having an obvious charge-discharge plateau potential is one of graphite, lithium titanate, and lithium iron phosphate.
A test method is used for three-electrode test, and comprises the following specific steps:
performing charging and discharging operation on a third electrode unit for 1-5 times by using a current of 0.33C, so that the surface state of positive and negative electrodes of the third electrode unit tends to be stable, and then adjusting the charge state of the third electrode unit according to the type of an active material corresponding to a selected third electrode;
the testing is carried out, the selected third electrode is used as a reference electrode, and the potential change condition of the anode/cathode of the basic winding core under the condition of passing current is tested according to the wiring mode of the three electrodes.
Preferably, when the third electrode corresponds to the single-layer negative electrode and the active material coated on the third electrode is graphite, the charge state of the third electrode unit is adjusted to 70-90% when the third electrode is used as a reference electrode;
the third electrode corresponds to the single-layer negative electrode, when the active material coated on the third electrode is lithium titanate, the charge state of the third electrode unit is adjusted to be 25-75% when the third electrode is used as a reference electrode;
and when the third electrode corresponds to the single-layer anode and the active material coated on the third electrode is lithium iron phosphate, the charge state of the third electrode unit serving as a reference electrode is adjusted to be 20-80%.
The battery cell has the beneficial effects that the charge state of the third electrode unit can be adjusted through charging and discharging, so that the reference electrode selected in the third electrode unit is in a stable state; the electric core for the three-electrode test adopts the electrodes of the positive and negative active materials containing good charge-discharge potential platforms as the reference electrodes in the three-electrode test system, can bear certain current in a proper charge state and maintain the stability of the potential in the continuous test, and can well monitor the potential change condition of the positive electrode and the negative electrode in the basic winding core in real time when the current passes; when the active material of the reference electrode in the third electrode unit is selected to be graphite, the lithium separation process of the carbon material cathode in the basic winding core can be better monitored, and better data support is provided for improving the performance of the electric core.
Drawings
FIG. 1 is a layered structure of the present invention;
FIG. 2 is a schematic view of a third electrode unit tab of the present invention positioned adjacent to a base jellyroll tab;
FIG. 3 is a schematic view of the third electrode unit tab and the base core tab being located on the same side in accordance with the present invention;
fig. 4 is a schematic structural view of the third electrode unit tab of the present invention disposed opposite to the base jellyroll tab.
Detailed Description
The invention is described in further detail below with reference to the figures and specific embodiments.
As shown in fig. 1-4, a specific embodiment of the present invention is an electrical core for three-electrode testing, including a basic winding core 1, an isolation film 2, and a third electrode unit 3, where the basic winding core 1 and the third electrode unit 3 are packaged together by an aluminum-plastic packaging film 4;
after the third electrode unit 3 is activated, the reference tab led out from the third electrode unit 3 has an obvious potential platform, and the reference tab led out from the third electrode unit 3 can be used as a reference electrode.
The basic winding core 1 comprises a positive plate 101 and a negative plate 102, a diaphragm 103 is arranged between the positive plate 101 and the negative plate 102, a positive tab 104 is welded on the positive plate 101, a negative tab 105 is welded on the negative plate 102, and the negative tab 104 and the positive tab 105 are led out from one side of the aluminum-plastic packaging film 4. Common anode and cathode materials can be adopted as the anode and cathode materials of the basic winding core 1, and the anode material includes but is not limited to lithium cobaltate (conventional voltage and high voltage), lithium manganate, lithium iron phosphate, nickel cobalt manganese ternary material and nickel cobalt aluminum; negative electrode materials include, but are not limited to, graphite (artificial graphite, natural graphite, mesocarbon microbeads, composite graphite), soft carbon, hard carbon, lithium titanate, silicon-containing materials, and the like.
The isolation film 2 is of a sheet structure, and the isolation film 2 is arranged between the basic roll core 1 and the third electrode unit 3.
The third electrode unit 3 is formed by combining a single-layer anode 301 coated on one side, a single-layer cathode 302 coated on one side and a composite film 303, wherein the composite film 303 is positioned between the coating surfaces of the single-layer anode 301 and the single-layer cathode 302;
the third electrode unit includes a first tab 304 welded to the single-layer positive electrode 301 and a second tab 305 welded to the single-layer negative electrode 302.
The basic winding core 1 comprises at least one layer of positive plate 101 and at least one layer of negative plate 102, and the basic winding core 1 is formed by processing the positive plate 101, the negative plate 102 and a diaphragm 103 in a winding or lamination mode.
The thickness of the isolation film 2 is not less than 25 μm, and the porosity is not more than 40%.
A preparation method of a battery cell for three-electrode testing comprises the following specific steps of:
s1, preparing a basic core: manufacturing a basic winding core according to the steps of slurry mixing, coating, rolling, slitting, tab setting and winding core assembling;
s2, preparing a third electrode unit: manufacturing a third electrode unit according to the steps of slurry mixing, coating, rolling, slitting, tab setting and laminating, wherein the single-layer positive electrode and the single-layer negative electrode are of single-side coating structures, and the back surfaces of the single-layer positive electrode and the single-layer negative electrode are not coated with adhesive paper;
s3, assembling into a shell: sequentially placing the basic winding core, the isolation film and the third electrode unit into a punched aluminum-plastic packaging film, adjusting the position directions of a positive lug and a negative lug of the basic winding core and the first lug and the second lug of the third electrode unit to avoid direct superposition contact, then packaging the aluminum-plastic packaging film, reserving an opening at one side, and then placing the packaging film into a vacuum oven for dewatering to obtain a dry cell;
s4, injection: and after the moisture of the dry battery cell in the vacuum oven is qualified, performing liquid injection and sealing operation to obtain the battery cell for the three-electrode test.
At least one electrode of the single-layer positive electrode and the single-layer negative electrode of the third electrode unit is coated with an electrode active material with an obvious charge-discharge platform potential, and the electrode active material with the obvious charge-discharge platform potential is one of graphite, lithium titanate and lithium iron phosphate.
A test method is used for three-electrode test, and comprises the following specific steps:
performing charging and discharging operation on a third electrode unit for 1-5 times by using a current of 0.33C, so that the surface state of positive and negative electrodes of the third electrode unit tends to be stable, and then adjusting the charge state of the third electrode unit according to the type of an active material corresponding to a selected third electrode;
the testing is carried out, the selected third electrode is used as a reference electrode, and the potential change condition of the anode/cathode of the basic winding core under the condition of passing current is tested according to the wiring mode of the three electrodes
When the third electrode corresponds to the single-layer negative electrode and the active material coated on the third electrode is graphite, the charge state of the third electrode is 70-90% when the third electrode is used as a reference electrode, and the electrode potential is stabilized at about 0.1V (relative to a lithium metal electrode);
the third electrode corresponds to the single-layer negative electrode, when the active material coated on the third electrode is lithium titanate, the charge state of the third electrode is 25% -75% when the third electrode is used as a reference electrode, and the electrode potential is stabilized at about 1.5V (relative lithium metal electrode);
when the third electrode corresponds to the single-layer anode and the active material coated on the third electrode is lithium iron phosphate, the charge state of the third electrode is 20-80% when the third electrode is used as a reference electrode, and the electrode potential is about 3.5V (relative to a lithium metal electrode).
Specific example 1 is as follows:
preparing a basic winding core, wherein the formula of the positive plate is that a positive active material (lithium cobaltate) is as follows: conductive agent (carbon black): binder (polyvinylidene fluoride) ═ 97:1.5:1.5, the formula of the negative plate is a negative active material (mesocarbon microbeads): conductive agent (graphite): CMC (sodium carboxymethylcellulose, thickener): SBR (styrene butadiene rubber, binder) 95:1:2: 2.
Firstly, preparing anode slurry and cathode slurry by stirring and mixing according to the proportion, wherein the anode adopts an oily system, and the cathode adopts a water-based system. And during stirring and mixing, preparing slurry by adopting double-planet stirring equipment under the condition of controlling the temperature and the vacuum degree, and transferring the slurry to a coating machine head for coating after testing that the viscosity, the solid content and the fineness meet the requirements.
The current collector of the positive plate is made of aluminum foil and has the thickness of 12-20 microns, and the current collector of the negative plate is made of copper foil and has the thickness of 6-10 microns. And rolling the coated positive and negative plates according to a set thickness. And cutting the rolled large roll into small rolls. And then, arranging a tab, welding at least one positive tab on the positive plate, and welding at least one negative tab on the negative plate. The positive and negative electrode tabs can be led out by welding on the foil or by the foil. And then stacking or winding the positive plate, the diaphragm and the negative plate into a winding core to obtain the basic winding core.
Preparing a third electrode unit, wherein the third electrode unit is of a single-layer coiled core structure, a single-layer anode and a single-layer cathode of the third electrode unit are coated on single surfaces, and adhesive paper is pasted on blank surfaces of the single-layer anode and the single-layer cathode (the materials of the single-layer anode and the single-layer cathode at least contain one of graphite, lithium titanate and lithium iron phosphate). The active material contained in the third electrode (reference electrode) in the third electrode unit is selected to be graphite.
The positive electrode slurry is prepared from an oil system, and when the active ingredient is the nickel cobalt lithium manganate ternary material, the component proportion of the positive electrode slurry is that of the positive electrode active material (the nickel cobalt lithium manganate ternary material): conductive agent: binder 97:1.5: 1.5. The cathode slurry is prepared from a water system, and the cathode slurry comprises the following components in percentage by weight: thickener (sodium carboxymethylcellulose): binder (styrene butadiene rubber) 97:1:1.5: 1.5. And (3) preparing anode and cathode slurry according to the mode in the previous section, coating a single surface to obtain a single-layer anode and a single-layer cathode, rolling and cutting according to a set thickness, correspondingly welding a first lug on the single-layer anode, and correspondingly welding a second lug on the single-layer cathode. And stacking the single-layer positive electrode, the diaphragm and the single-layer negative electrode to obtain a third electrode unit.
Aligning and stacking the basic roll core unit, the isolation film (inert sheet) and the third electrode unit according to a given tab outlet mode, putting the basic roll core unit, the isolation film and the third electrode unit into an aluminum-plastic packaging film formed by punching, and carrying out top sealing and side sealing (as shown in figure 2, the top ends of the positive tab and the negative tab extend out, and the reference tab extends out from the side surface). And baking the packaged battery cell in a vacuum oven, and injecting and standing the battery cell after the water content is qualified.
When the battery cell is used, the third electrode (single-layer negative electrode, corresponding to the active material being graphite) of the third electrode unit is activated: and (3) circulating charge-discharge by 0.33C current for 3 times to make the positive and negative electrode surfaces of the third electrode unit reach a stable state, wherein the second electrode ear corresponding to the single-layer negative electrode is selected as the third electrode, the active material of the third electrode ear is graphite, and the SOC state (charge state) of the third electrode unit is controlled to be 80% by charge-discharge operation. And then, a third electrode (a second tab corresponding to the single-layer negative electrode) is taken as a reference electrode and is connected with the positive electrode and the negative electrode of the basic winding core according to a three-electrode test method so as to monitor the voltage change condition of the positive electrode and the negative electrode of the basic winding core when current flows, and because the third electrode is graphite, the lithium precipitation process of the negative electrode of the carbon material in the basic winding core can be monitored, and better data support is provided for improving the performance of the cell. The battery cell is used for carrying out battery cycle performance test, 300 times of charge-discharge cycle and 40 days multiplied by 24 hours of continuous cycle test, the potential of the third electrode can be continuously stable, and correction is not needed in the midway; when the traditional three-electrode battery is circulated for about ten times, the potential of the reference electrode can be greatly changed due to the loss of lithium on the surface of the copper wire, and the test can be continued after correction.
The electric core can adjust the charge state of the third electrode unit through charge and discharge, so that the reference electrode selected in the third electrode unit is in a stable state; the battery core adopts the electrodes of the positive and negative active materials containing good charge-discharge potential platforms as reference electrodes in a three-electrode test system, can bear certain current in a proper charge state and maintain the stability of potential in continuous test, and can well monitor the potential change condition of the positive electrode and the negative electrode in the basic winding core in real time when the current passes; when the active material of the reference electrode in the third electrode unit is selected to be graphite, the lithium separation process of the carbon material cathode in the basic winding core can be better monitored, and better data support is provided for improving the performance of the electric core.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and any minor modifications, equivalent replacements and improvements made to the above embodiment according to the technical spirit of the present invention should be included in the protection scope of the technical solution of the present invention.
Claims (9)
1. An electricity core for three electrode test which characterized in that: the device comprises a basic winding core, an isolation film and a third electrode unit, wherein the basic winding core and the third electrode unit are packaged together through an aluminum-plastic packaging film;
after the third electrode unit is activated, one electrode with an obvious charge-discharge platform in the third electrode unit is selected as a third electrode, and the third electrode can be used as a reference battery after the charge state is adjusted.
2. The cell for three-electrode testing of claim 1, wherein: the basic winding core comprises a positive plate and a negative plate, a diaphragm is arranged between the positive plate and the negative plate, a positive lug is welded on the positive plate, a negative lug is welded on the negative plate, and the positive lug and the negative lug are led out from the top end of the aluminum-plastic packaging film;
the isolating film is of a sheet structure and is arranged between the basic roll core and the third electrode unit.
3. The cell for three-electrode testing of claim 1, wherein: the third electrode unit is formed by combining a single-layer anode coated on one side, a single-layer cathode coated on one side and a composite film, and the composite film is positioned between the coating surfaces of the single-layer anode and the single-layer cathode;
the single-layer positive electrode is provided with a first tab, the single-layer negative electrode is provided with a second tab, and the first tab and the second tab are led out from the top end, the bottom end or the side end of the aluminum-plastic film.
4. The cell for three-electrode testing of claim 2, wherein: the basic winding core comprises at least one layer of positive plate and one layer of negative plate, and is formed by processing the positive plate, the negative plate and the diaphragm in a winding or laminating mode.
5. The cell for three-electrode testing of claim 1, wherein: the thickness of the isolating film is not less than 25 μm, and the porosity is not more than 40%.
6. A preparation method of a battery cell for three-electrode testing is characterized by comprising the following steps: the electrical core for a three-electrode test according to any of claims 1 to 5, comprising the following specific steps:
s1, preparing a basic core: manufacturing a basic winding core according to the steps of slurry mixing, coating, rolling, slitting, tab setting and winding core assembling;
s2, preparing a third electrode unit: manufacturing a third electrode unit according to the steps of slurry mixing, coating, rolling, slitting, tab setting and laminating, wherein the single-layer positive electrode and the single-layer negative electrode are of single-side coating structures, and the back surfaces of the single-layer positive electrode and the single-layer negative electrode are not coated with adhesive paper;
s3, assembling into a shell: sequentially placing the basic winding core, the isolation film and the third electrode unit into a punched aluminum-plastic packaging film, adjusting the position directions of a positive lug and a negative lug of the basic winding core and the first lug and the second lug of the third electrode unit to avoid direct superposition contact, then packaging the aluminum-plastic packaging film, reserving an opening at one side, and then placing the packaging film into a vacuum oven for dewatering to obtain a dry cell;
s4, injection: and after the moisture of the dry battery cell in the vacuum oven is qualified, performing liquid injection and sealing operation to obtain the battery cell for the three-electrode test.
7. The cell preparation method of claim 6, wherein: at least one electrode of the single-layer positive electrode and the single-layer negative electrode of the third electrode unit is coated with an electrode active material with an obvious charge-discharge platform potential, and the electrode active material with the obvious charge-discharge platform potential is one of graphite, lithium titanate and lithium iron phosphate.
8. A method of testing, characterized by: the electrical core for a three-electrode test according to any of claims 1 to 6, comprising the following specific steps:
performing charging and discharging operation on a third electrode unit for 1-5 times by using a current of 0.33C, so that the surface state of positive and negative electrodes of the third electrode unit tends to be stable, and then adjusting the charge state of the third electrode unit according to the type of an active material corresponding to a selected third electrode;
the testing is carried out, the selected third electrode is used as a reference electrode, and the potential change condition of the anode/cathode of the basic winding core under the condition of passing current is tested according to the wiring mode of the three electrodes.
9. The test method of claim 8, wherein: when the third electrode corresponds to the single-layer negative electrode and the active material coated on the third electrode is graphite, the charge state of the third electrode unit is adjusted to 70-90% when the third electrode is used as a reference electrode;
the third electrode corresponds to the single-layer negative electrode, when the active material coated on the third electrode is lithium titanate, the charge state of the third electrode unit is adjusted to be 25-75% when the third electrode is used as a reference electrode;
and when the third electrode corresponds to the single-layer anode and the active material coated on the third electrode is lithium iron phosphate, the charge state of the third electrode unit serving as a reference electrode is adjusted to be 20-80%.
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113422115A (en) * | 2021-07-02 | 2021-09-21 | 广州小鹏汽车科技有限公司 | Lithium ion battery cell, preparation method of lithium ion battery cell and lithium analysis detection method |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0807826A2 (en) * | 1996-05-14 | 1997-11-19 | Intra Development A/S | Pilot cell for a battery |
| CN102593539A (en) * | 2012-02-13 | 2012-07-18 | 东莞新能源科技有限公司 | Method for monitoring potentials of anode and cathode of lithium-ion battery |
| WO2015049778A1 (en) * | 2013-10-04 | 2015-04-09 | 株式会社日立製作所 | Lithium ion secondary battery, lithium ion secondary battery system, method for detecting potential in lithium ion secondary battery, and method for controlling lithium ion secondary battery |
| CN105206867A (en) * | 2015-10-09 | 2015-12-30 | 天津市捷威动力工业有限公司 | Three-electrode system for lithium ion battery and preparation method thereof |
-
2021
- 2021-03-25 CN CN202110319243.1A patent/CN112909368A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0807826A2 (en) * | 1996-05-14 | 1997-11-19 | Intra Development A/S | Pilot cell for a battery |
| CN102593539A (en) * | 2012-02-13 | 2012-07-18 | 东莞新能源科技有限公司 | Method for monitoring potentials of anode and cathode of lithium-ion battery |
| WO2015049778A1 (en) * | 2013-10-04 | 2015-04-09 | 株式会社日立製作所 | Lithium ion secondary battery, lithium ion secondary battery system, method for detecting potential in lithium ion secondary battery, and method for controlling lithium ion secondary battery |
| CN105206867A (en) * | 2015-10-09 | 2015-12-30 | 天津市捷威动力工业有限公司 | Three-electrode system for lithium ion battery and preparation method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113422115A (en) * | 2021-07-02 | 2021-09-21 | 广州小鹏汽车科技有限公司 | Lithium ion battery cell, preparation method of lithium ion battery cell and lithium analysis detection method |
| CN113422115B (en) * | 2021-07-02 | 2023-08-25 | 广州小鹏汽车科技有限公司 | Lithium ion battery cell, lithium ion battery cell preparation method and lithium analysis detection method |
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