A secondary battery

Abstract

The present application provides a kind of secondary battery, especially alkali metal secondary battery, it includes positive pole, negative pole and electrolyte layer, wherein: the electrolyte layer is made of non-alkali metal monovalent ion conductor;The secondary battery is sodium secondary battery or lithium secondary battery.The secondary battery of the present application, such as alkali metal secondary battery, is more stable under environmental conditions and easy to prepare, low in price, and the cycle life of the battery is greatly improved.

Description

Technical Field

[0001] This invention belongs to the field of energy storage technology. Specifically, this invention relates to a secondary battery. More specifically, this invention relates to an alkali metal secondary battery. Background Technology

[0002] Lithium / sodium alkali metal secondary batteries, as a form of chemical energy storage, are characterized by high energy density and long lifespan. With industry development, solid-state electrolytes and high specific capacity anodes have become the future directions for secondary batteries.

[0003] Sulfide and halide solid electrolytes have excellent properties such as high ionic conductivity and are considered to be the preferred materials for future solid-state battery electrolytes. However, alkaline ionic sulfide and halide electrolytes are prone to react with water and require a harsh manufacturing environment.

[0004] Currently, inorganic solid-state electrolytes can be further classified into lithium superionic conductors (LISICON), sodium superionic conductors (NASICON), argyrodite, perovskite, antiperovskite, and garnet types. Sulfide solid-state electrolytes have attracted significant attention due to their high ionic conductivity, such as Li... + Ionic conductors: LiPS5Cl, Li3PS4, LiSnS4, Li3BO3, Li4SiO4, Li7P3S 11 Sodium ion conductor Na3PS 4、 Na3SbS4, Na 11 Sn2SbS 12 .

[0005] Cu + and Ag + Early ionic conductor materials were primarily solid electrolytes that were extensively studied, commonly using Cu6PS5X and Ag6PS5X (X = Cl, Br, I), constructing related Cu structures through homogeneous ion transport. + and Ag + Secondary batteries. See JP49007169-A, CN104851473-A, and Journal of Non-Crystalline Solids, 2019, 521, 119476; Journal of Physics and Chemistry of Solids, 2003, 64, 1261; or Research progress on sodium ion sulfide solid electrolytes, Energy Storage Science and Technology, 2020, 9, 1266.

[0006] Therefore, there is an urgent need for a solid electrolyte that can be used in alkali metal secondary batteries, which is more stable and easier to prepare under environmental conditions, and can significantly improve the cycle life of alkali metal secondary batteries. Summary of the Invention

[0007] The purpose of this invention is to provide a secondary battery, especially an alkali metal secondary battery, which is more stable and easier to manufacture under environmental conditions, inexpensive, and has a significantly improved cycle life.

[0008] The above-mentioned objective of the present invention is achieved through the following technical solution.

[0009] This invention provides a secondary battery comprising a positive electrode, a negative electrode, and an electrolyte layer, wherein:

[0010] The electrolyte layer is composed of a non-alkali metal monovalent ion conductor;

[0011] The secondary battery is a sodium secondary battery or a lithium secondary battery.

[0012] The inventors of this application unexpectedly discovered that when a battery is prepared using non-alkali metal copper and / or silver ion conductors as the initial electrolyte, copper and / or silver ions can be replaced by alkali metal ions during the battery formation process to form a lithium / sodium ion-conducting solid electrolyte in situ. The copper and / or silver layer formed at the electrolyte / anode interface during the formation process can homogenize interfacial ion transport, inhibit the growth of lithium / sodium dendrites, and increase the critical current density for alkali metal secondary batteries.

[0013] Preferably, in the secondary battery of the present invention, the non-alkali metal monovalent ion conductor is capable of ionizing Cu. + Compounds of ions and / or capable of ionizing Ag + Compounds containing ions.

[0014] Preferably, in the secondary battery of the present invention, the non-alkali metal monovalent ion conductor is selected from Cu6PS5Cl, Cu6PS5Br, Cu6PS5I, Cu3PS4, and Cu7P3S. 11 , CuCl, Ag6PS5Cl, Ag6PS5Br, Ag6PS5I, Ag3PS4, Ag7P3S 11 One or more of AgCl.

[0015] Preferably, in the secondary battery of the present invention, when the secondary battery is a sodium secondary battery, the positive electrode comprises one or more of the following positive electrode active materials: sodium cobaltate, sodium manganate, sodium ferrite, sodium vanadium phosphate, and Prussian white.

[0016] Preferably, in the secondary battery of the present invention, when the secondary battery is a lithium secondary battery, the positive electrode comprises one or more of the following positive electrode active materials: NCM ternary positive electrode material, NCA ternary positive electrode material, LFP lithium iron phosphate and LMO lithium manganese oxide, LNMO lithium nickel manganese oxide, lithium-rich manganese-based positive electrode material and lithium sulfide.

[0017] Preferably, in the secondary battery of the present invention, the negative electrode includes a conductive current collector.

[0018] Preferably, in the secondary battery of the present invention, the negative electrode includes a conductive current collector and an inactive conductive coating located on the conductive current collector.

[0019] Preferably, in the secondary battery of the present invention, the inactive conductive coating is composed of carbon-based materials, metals, or alloys.

[0020] Preferably, in the secondary battery of the present invention, the negative electrode includes a conductive current collector and a negative electrode active material located on the conductive current collector;

[0021] Preferably, in the secondary battery of the present invention, when the secondary battery is a sodium secondary battery, the negative electrode active material includes, but is not limited to, one or more of the following materials: hard carbon, soft carbon and antimony oxide.

[0022] Preferably, in the secondary battery of the present invention, when the secondary battery is a lithium secondary battery, the negative electrode active material includes, but is not limited to, one or more of the following materials: graphite, hard carbon, soft carbon, silicon-carbon and silicon-tin based materials.

[0023] Preferably, in the secondary battery of the present invention, when the secondary battery is a sodium secondary battery, the conductive current collector includes, but is not limited to, aluminum foil or carbon-coated aluminum foil.

[0024] Preferably, in the secondary battery of the present invention, when the secondary battery is a lithium secondary battery, the conductive current collector includes, but is not limited to, copper foil or carbon-coated copper foil.

[0025] In some specific embodiments of the present invention, the non-alkali metal electrolyte layer of the present invention is prepared and composited on the positive electrode surface by methods such as powder pressing, coating, dry film formation, chemical and physical deposition, etc., and there are no particular limitations.

[0026] The working principle of the secondary battery of the present invention is as follows:

[0027] 1) After stacking and pressing the positive electrode / non-alkali metal electrolyte layer / negative electrode, charging is performed. Non-alkali metal copper and / or silver ions in the electrolyte are replaced by alkali metal lithium and / or sodium ions. Copper and / or silver ions are deposited at the electrolyte / negative electrode interface, while lithium and / or sodium ions continue to react with the negative electrode active material; or

[0028] 2) After the positive electrode / non-alkali metal electrolyte layer / negative electrode is stacked and pressed together, it is charged. In the electrolyte, non-alkali metal copper and / or silver ions are replaced by alkali metal lithium and / or sodium ions. Copper and / or silver ions are deposited at the electrolyte / negative electrode interface, and lithium and / or sodium ions continue to be deposited in the metal lithium / sodium battery without active materials through the electrolyte.

[0029] The present invention has the following beneficial effects:

[0030] The secondary battery of this invention exhibits higher stability under atmospheric conditions and significantly improves the cycle life of secondary batteries, especially alkali metal secondary batteries with no active material in the negative electrode. This is mainly attributed to the Li released from the lithium / sodium positive electrode through an electrochemical process. + and / or Na + Substitution of Cu in copper and / or silver ion conductors + and / or Ag + This process induces Cu and / or Ag to deposit at the electrolyte / anode interface, forming a functional interface layer that inhibits lithium / sodium dendrite formation. The aforementioned technical effects of this invention are even more pronounced in secondary batteries that initially lack anode active material and are assembled using only anode current collectors. Attached Figure Description

[0031] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings, wherein:

[0032] Figure 1 The image shows a scanning electron microscope (SEM) image of the negative electrode interface constructed by the electrochemical method in Example 3 of the present invention.

[0033] Figure 2 A scanning electron microscope image of the negative electrode interface constructed in Comparative Example 1 is shown.

[0034] Figure 3 The secondary battery prepared according to Example 3 of the present invention is shown to have a performance of 2 mA / cm². 2 Charging curves at current density;

[0035] Figure 4 The secondary cell prepared in Comparative Example 1 is shown at 2 mA / cm 2 Charging curves at current density. Detailed Implementation

[0036] The present invention will be further described in detail below with reference to specific embodiments. The embodiments given are only for illustrating the present invention and are not intended to limit the scope of the present invention.

[0037] Example 1

[0038] In a dry environment with a dew point of -40℃, 10 mg of Cu6PS5Br was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. LiNi 0.8 Co 0.1 Mn 0.1 O2 and Li6PS5Cl were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was placed on one side of the electrolyte sheet and kept under a pressure of 360 MPa for 10 min. Graphite and Li6PS5Cl were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite negative electrode. 20 mg of this mixture was placed on the other side of the electrolyte sheet, and a Cu current collector was then attached to the surface. The mixture was kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a1.

[0039] Example 2

[0040] In a dry environment with a dew point of -40℃, 10 mg of Cu3PS4 was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. LiNi 0.8 Co 0.1 Mn 0.1 O2 and Li6PS5Cl were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was placed on one side of the electrolyte sheet and kept under a pressure of 360 MPa for 10 min. Graphite and Li3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite negative electrode. 20 mg of this mixture was placed on the other side of the electrolyte sheet, and a Cu current collector was then attached to the surface. The mixture was kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a2.

[0041] Example 3

[0042] In a dry environment with a dew point of -40℃, 10 mg of Ag6PS5Cl was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. LiNi 0.8 Co 0.1 Mn 0.1O2 and Li6PS5Cl were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of the mixture was weighed and placed on one side of the electrolyte sheet and kept under a pressure of 360 MPa for 10 min. A carbon-coated copper foil was cut into a circular piece with a diameter of 9.5 mm and placed on the other side of the electrolyte sheet. The mixture was kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a3.

[0043] Figure 1 This image shows a scanning electron microscope (SEM) photograph of the negative electrode interface constructed by the electrochemical method in Example 3 of the present invention. EDS spectroscopy reveals that, due to the Li on the positive electrode side... + The Ag in Ag6PS5Cl at the critical negative electrode interface migrates towards the negative electrode side. + Leaving the S-containing electrolyte portion, an Ag-rich layer forms at the interface through reduction. The Ag at the interface then induces subsequently migrating Li to form a uniform lithium deposition at the interface. Therefore, in batteries using carbon-coated copper foil current collectors, at 2 mA / cm²... 2 No dendrites formed even under high current density deposition.

[0044] Figure 3 The secondary battery prepared according to Example 3 of the present invention is shown to have a performance of 2 mA / cm². 2 The charging curve at current density shows that the battery charging curve is smooth and normal, with no short circuit observed.

[0045] Example 4

[0046] In a dry environment with a dew point of -40℃, 10 mg of CuCl was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. LiNi 0.8 Co 0.1 Mn 0.1 O2 and Li6PS5Cl were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of the mixture was weighed and placed on one side of the electrolyte sheet and kept under a pressure of 360 MPa for 10 min. A carbon-coated copper foil was cut into a circular piece with a diameter of 9.5 mm and placed on the other side of the electrolyte sheet. The mixture was kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a4.

[0047] Example 5

[0048] In a dry environment with a dew point of -40℃, 10 mg of Ag6PS5Cl was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. NaCoO2 and Na3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was weighed and placed on one side of the electrolyte sheet, and kept under a pressure of 360 MPa for 10 min. Carbon-coated aluminum foil, cut into 9.5 mm diameter discs, was placed on the other side of the electrolyte sheet and kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a5.

[0049] Example 6

[0050] In a dry environment with a dew point of -40℃, 10 mg of Ag6PS5Br was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. NaCoO2 and Na3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was weighed and placed on one side of the electrolyte sheet, and kept under a pressure of 360 MPa for 10 min. Sb2O3 and Na3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite negative electrode. 30 mg of this mixture was weighed and placed on the other side of the electrolyte sheet, and kept under a pressure of 360 MPa for 10 min. Then, an Al current collector was attached to the surface, and the mixture was kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a6.

[0051] Example 7

[0052] In a dry environment with a dew point of -40℃, 10 mg of Ag6PS5I was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. NaCoO2 and Na3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was weighed and placed on one side of the electrolyte sheet, and kept under a pressure of 360 MPa for 10 min. Hard carbon and Na6PS5I were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite negative electrode. 20 mg of this mixture was weighed and placed on the other side of the electrolyte sheet. An Al current collector was then attached to the surface, and the mixture was kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a7.

[0053] Example 8

[0054] In a dry environment with a dew point of -40℃, 10 mg of Ag3PS4 was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. NaCoO2 and Na3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was weighed and placed on one side of the electrolyte sheet, and kept under a pressure of 360 MPa for 10 min. Carbon-coated aluminum foil, cut into 9.5 mm diameter discs, was placed on the other side of the electrolyte sheet and kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a8.

[0055] Example 9

[0056] Weigh 10 mg of Ag7P3S in a dry environment with a dew point of -40°C. 11 A solid electrolyte sheet was obtained by placing the electrolyte in a 10 mm diameter PTFE sleeve and maintaining it at 360 MPa for 10 min. NaCoO2 and Na3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was placed on one side of the electrolyte sheet and maintained at 360 MPa for 10 min. A carbon-coated aluminum foil, cut into 9.5 mm diameter circles, was placed on the other side of the electrolyte sheet and maintained at 10 MPa for 5 min. The resulting secondary battery is denoted as a9.

[0057] Example 10

[0058] In a dry environment with a dew point of -40℃, 10 mg of AgCl was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. NaCoO2 and Na3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was weighed and placed on one side of the electrolyte sheet, and kept under a pressure of 360 MPa for 10 min. Carbon-coated aluminum foil, cut into 9.5 mm diameter discs, was placed on the other side of the electrolyte sheet and kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as a10.

[0059] Comparative Example 1

[0060] In a dry environment with a dew point of -40℃, 10 mg of Li6PS5Cl was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. LiNi 0.8 Co 0.1 Mn 0.1O2 and Li6PS5Cl were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of the mixture was weighed and placed on one side of the electrolyte sheet and kept under a pressure of 360 MPa for 10 min. A carbon-coated copper-aluminum foil was cut into a circular piece with a diameter of 9.5 mm and placed on the other side of the electrolyte sheet. The mixture was kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as b1.

[0061] Figure 2 A scanning electron microscope (SEM) image of the negative electrode interface constructed in Comparative Example 1 is shown. EDS spectroscopy reveals that, due to the absence of interface-induced deposition, at 2 mA / cm²... 2 Lithium dendrites grow under current density deposition, and their entry into the electrolyte can be clearly observed, triggering a battery short circuit.

[0062] Figure 4 The secondary cell prepared in Comparative Example 1 is shown at 2 mA / cm 2 The charging curve at current density reveals abnormal voltage fluctuations during battery charging. A rapid voltage drop occurs in the initial stages of charging, and the battery fails to reach the 4.2V plateau, exhibiting abnormal capacity changes.

[0063] Comparative Example 2

[0064] In a dry environment with a dew point of -40℃, 10 mg of Na3PS4 was weighed and placed in a 10 mm diameter PTFE sleeve, and kept under a pressure of 360 MPa for 10 min to obtain a solid electrolyte sheet. NaCoO2 and Na3PS4 were mixed evenly in a mortar at a mass ratio of 7:3 to form a composite positive electrode. 30 mg of this mixture was weighed and placed on one side of the electrolyte sheet, and kept under a pressure of 360 MPa for 10 min. Carbon-coated aluminum foil, cut into 9.5 mm diameter discs, was placed on the other side of the electrolyte sheet and kept under a pressure of 10 MPa for 5 min. The resulting secondary battery is denoted as b2.

[0065] Secondary battery short circuit test

[0066] The secondary batteries of Examples 1-11 and Comparative Examples 1-2 were subjected to constant current charging at a current density of 2 mA / cm² in dry environments with a dew point of 25°C and -40°C. 2 After charging for one hour, observe the voltage of the secondary battery. If the voltage is 0V, it is determined to be in a short-circuit state.

[0067] Air stability test

[0068] The electrolyte material was placed in a dry environment with an ambient dew point of -40°C, and then stored at 25°C for 24 h. After that, 100 mg of the environmentally exposed and unexposed electrolytes were cold-pressed at 360 MPa for 10 min. The ionic conductivity of the electrolyte sheet was then tested by AC impedance method, and the retention rate was calculated using the ratio between the two tests.

[0069] 100-cycle capacity retention test

[0070] In a dry environment with a dew point of -40℃, the secondary battery was first pre-charged and discharged at a rate of 0.1C under a test pressure of 10 MPa and a temperature of 60℃. Subsequently, it was subjected to a low-rate charge-discharge cycle of 0.2C. Based on the ratio of the discharge capacity of the first 0.2C cycle to that of the 100th cycle, the capacity retention rate of the 100th cycle was calculated.

[0071] Table 1. Short-circuit conditions and ionic conductivity retention of secondary batteries in the examples and comparative examples.

[0072] Serial Number Electrolyte types Positive electrode active material negative electrode Secondary battery short circuit Electrolyte ionic conductivity retention rate (%) a1 <![CDATA[Cu6PS5Br]]> NCM Graphite anode No short circuit 92 a2 <![CDATA[Cu3PS4]]> NCM Graphite anode No short circuit 86 a3 <![CDATA[Ag6PS5Cl]]> NCM Carbon-coated copper foil No short circuit 96 a4 CuCl NCM Carbon-coated copper foil No short circuit 91 a5 <![CDATA[Ag6PS5Cl]]> Sodium cobaltate Carbon-coated aluminum foil No short circuit 89 a6 <![CDATA[Ag6PS5Br]]> Sodium cobaltate Antimony oxide anode No short circuit 76 a7 <![CDATA[Ag6PS5I]]> Sodium cobaltate Hard carbon anode No short circuit 79 a8 <![CDATA[Ag3PS4]]> Sodium cobaltate Carbon-coated aluminum foil No short circuit 80 a9 <![CDATA[Ag7P3S 11 ]]> Sodium cobaltate Carbon-coated aluminum foil No short circuit 67 a10 AgCl Sodium cobaltate Carbon-coated aluminum foil No short circuit 77 b1 <![CDATA[Li6PS5Cl]]> NCM Carbon-coated copper foil Short circuit 34 b2 <![CDATA[Na3PS4]]> Sodium cobaltate Carbon-coated aluminum foil Short circuit 17

[0073] Table 1 shows that the alkali metal secondary battery of the present invention has higher stability under atmospheric conditions, and the uniformity of alkali metal ion transport to the negative electrode is greatly improved, overcoming the problem of easy short circuit of the battery.

[0074] Table 2 Cyclic capacity retention rates of the examples and comparative examples

[0075] Serial Number Electrolyte types Positive electrode active material negative electrode Capacity retention rate after 100 cycles (%) a3 <![CDATA[Ag6PS5Cl]]> NCM Carbon-coated copper foil 88 a4 CuCl NCM Carbon-coated copper foil 63 a5 <![CDATA[Ag6PS5Cl]]> Sodium cobaltate Carbon-coated aluminum foil 73 a8 <![CDATA[Ag3PS4]]> Sodium cobaltate Carbon-coated aluminum foil 72 a10 AgCl Sodium cobaltate Carbon-coated aluminum foil 75 b1 <![CDATA[Li6PS5Cl]]> NCM Carbon-coated copper foil 19 b2 <![CDATA[Na3PS4]]> Sodium cobaltate Carbon-coated aluminum foil 12

[0076] Table 3 shows that the alkali metal secondary battery of the present invention has a significant improvement in cycle performance, which is reflected in the substantial increase in the recycling rate of lithium metal and sodium metal.

Claims

1. A secondary battery comprising a positive electrode, a negative electrode, and an electrolyte layer, wherein: The electrolyte layer is composed of a non-alkali metal monovalent ion conductor; The secondary battery is a sodium secondary battery or a lithium secondary battery.

2. The secondary battery according to claim 1, wherein, The non-alkali metal monovalent ion conductor is capable of ionizing Cu. + Compounds of ions and / or capable of ionizing Ag + Compounds containing ions.

3. The secondary battery according to claim 1, wherein, The non-alkali metal monovalent ionic conductor is selected from Cu6PS5Cl, Cu6PS5Br, Cu6PS5I, Cu3PS4, and Cu7P3S. 11 , CuCl, Ag6PS5Cl, Ag6PS5Br, Ag6PS5I, Ag3PS4, Ag7P3S 11 And one or more of AgCl.

4. The secondary battery according to claim 1, wherein, When the secondary battery is a sodium secondary battery, the positive electrode contains one or more of the following positive electrode active materials: sodium cobaltate, sodium manganate, sodium ferrite, sodium vanadium phosphate, and Prussian white.

5. The secondary battery according to claim 1, wherein, When the secondary battery is a lithium secondary battery, the positive electrode comprises one or more of the following positive electrode active materials: NCM ternary positive electrode material, NCA ternary positive electrode material, LFP lithium iron phosphate, LMO lithium manganese oxide, LNMO lithium nickel manganese oxide, lithium-rich manganese-based positive electrode material, and lithium sulfide.

6. The secondary battery according to claim 1, wherein, The negative electrode includes a conductive current collector.

7. The secondary battery according to claim 1, wherein, The negative electrode includes a conductive current collector and an inactive conductive coating located on the conductive current collector; Preferably, the inactive conductive coating is composed of carbon-based materials, metals, or alloys.

8. The secondary battery according to claim 1, wherein, The negative electrode includes a conductive current collector and a negative electrode active material located on the conductive current collector; Preferably, when the secondary battery is a sodium secondary battery, the negative electrode active material includes one or more of the following materials: hard carbon, soft carbon, and antimony oxide; Preferably, when the secondary battery is a lithium secondary battery, the negative electrode active material includes one or more of the following materials: graphite, hard carbon, soft carbon, silicon-carbon, and silicon-tin based materials.

9. The secondary battery according to any one of claims 6-8, wherein, When the secondary battery is a sodium secondary battery, the conductive current collector includes aluminum foil or carbon-coated aluminum foil; Preferably, when the secondary battery is a lithium secondary battery, the conductive current collector includes copper foil or carbon-coated copper foil.

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