Porous high-nickel ternary positive electrode material and preparation method and application thereof

Abstract

The invention provides a porous high-nickel ternary positive electrode material and a preparation method and application thereof, the porous high-nickel ternary positive electrode material comprises a matrix and a coating layer on the surface of the matrix, and the matrix and the coating layer are both of a porous structure; the matrix comprises LiNiaCobMn1-a-b-cO2, a is more than or equal to 0.9 and less than 1, and b is more than 0 and less than or equal to 0.07; and coating elements in the coating layer comprise any one or a combination of at least two of B, P, W, Nb, Ta, Mo or Sb. The pores in the porous high-nickel ternary positive electrode material not only can accelerate the de-intercalation speed of lithium ions and improve the specific capacity, but also can relieve the mechanical stress caused by phase change in the charging and discharging process so as to improve the cycle performance, and the coating layer can further improve the ionic conductivity of the material, so that the performance of the material is improved. Therefore, the capacity and the cycle performance of the positive electrode material are simultaneously improved.

Description

Technical Field

[0001] This invention belongs to the field of battery technology and relates to a porous high-nickel ternary cathode material, its preparation method, and its application. Background Technology

[0002] In recent years, with the rapid development of the new energy vehicle industry, people have increasingly higher requirements for the driving range of new energy vehicles, leading to a rapid increase in demand for high-energy-density lithium-ion batteries. High-nickel ternary cathode materials, due to their high theoretical specific capacity, are considered the most promising candidates for next-generation lithium-ion battery cathode materials.

[0003] To meet the demand for higher energy density, one approach is to increase the specific capacity of the cathode material by increasing the Ni content. However, as the Ni content gradually approaches 100%, the capacity improvement effect weakens significantly. Furthermore, the higher the Ni content, the more severe the Li / Ni mixing occurs, affecting cycle performance and increasing DCR. On the other hand, another approach is to improve capacity by coating the surface of the cathode material with substances that have good ionic and electronic conductivity. Although a small amount of coating can improve capacity to some extent, the improvement is limited. Moreover, if the coating amount is too large, the specific capacity will actually decrease because the coating layer is inert.

[0004] Based on the above research, there is a need to provide a cathode material that can improve both capacity and cycle performance. Summary of the Invention

[0005] The purpose of this invention is to provide a porous high-nickel ternary cathode material, its preparation method and application. The pores in the porous high-nickel ternary cathode material can not only accelerate the lithium-ion insertion / extraction rate and improve the specific capacity, but also alleviate the mechanical stress caused by phase transition during charging and discharging, thereby improving the cycle performance. Furthermore, the coating layer can further improve the ionic conductivity of the material, thus simultaneously improving the capacity and cycle performance of the cathode material.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a porous high-nickel ternary cathode material, the porous high-nickel ternary cathode material comprising a substrate and a coating layer on the surface of the substrate, wherein both the substrate and the coating layer are porous structures;

[0008] The matrix includes LiNi a Co b Mn 1-a-b-cO2, where 0.9 ≤ a < 1, for example, it can be 0.9, 0.91, 0.92, 0.93, 0.94, 0.95 or 0.96, and 0 < b ≤ 0.07, for example, it can be 0.01, 0.02, 0.03, 0.04, 0.05, 0.06 or 0.07;

[0009] The coating layer includes any one or a combination of at least two of B, P, W, Nb, Ta, Mo, or Sb.

[0010] The porous high-nickel ternary cathode material of the present invention includes a substrate and a coating layer, both of which are porous structures with pores uniformly distributed within the material. This not only enhances the Li-Nickel content but also... + The diffusion rate is increased, the specific capacity is improved, and the porous structure can alleviate the mechanical stress caused by phase transition during charging and discharging, thereby improving the cycle performance of the porous high-nickel ternary cathode material; furthermore, the coating elements in the coating layer can further improve the ionic conductivity of the material, thereby further improving the electrochemical performance of the material.

[0011] Preferably, the pore size of the porous high-nickel ternary cathode material is 1 to 13 nm, for example, it can be 1 nm, 3 nm, 5 nm, 7 nm, 9 nm, 11 nm or 13 nm, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 2 to 4 nm.

[0012] The porous high-nickel ternary cathode material of this invention has a small pore size. Small pores are more conducive to accelerating the lithium ion insertion / extraction rate and alleviating the mechanical stress caused by phase transition. In other words, small pores are more conducive to simultaneously improving the capacity and cycle performance of the material. If the pore size is too large, the structure will be unstable and will easily collapse during charging and discharging, resulting in poor cycle performance. However, if the pore size is too small, it will affect the lithium ion insertion / extraction rate and ultimately affect the capacity.

[0013] Preferably, the porosity of the porous high-nickel ternary cathode material is 30% to 90%, for example, it can be 30%, 40%, 50%, 60%, 70%, 80% or 90%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 40% to 60%.

[0014] Preferably, in the porous high-nickel ternary cathode material, the content of the coating layer is within 9.0 wt%, for example, it can be 9.0 wt%, 8.0 wt%, 7.0 wt%, 6.0 wt%, 5.0 wt%, 4.0 wt%, 3.0 wt%, 2.0 wt%, 1.0 wt%, or 0.1 wt%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 0.02 to 5.6 wt%.

[0015] Preferably, the matrix further includes a doping element, which includes any one or a combination of at least two of P, S, or Al.

[0016] The porous structure of the present invention is obtained by creating pores with a first pore-forming agent. The first pore-forming agent can not only create pores but also remain in the matrix to achieve element doping.

[0017] Preferably, the coating elements in the coating layer include B and / or P.

[0018] The coating element in the coating layer of the present invention is preferably B and / or P, because the corresponding coating material itself has a low melting point and can be uniformly coated on the surface of the substrate compared with other coating elements.

[0019] Preferably, the coating layer comprises lithium borate and / or lithium phosphate.

[0020] Preferably, the porous high-nickel ternary cathode material further includes an outer shell layer, which is located on the surface of the coating layer away from the substrate.

[0021] The present invention can be further modified by coating, but no matter what coating method or coating material is used, the porous structure inside the material will not be changed. After coating modification, the material performance will be further improved. The capacity after coating is the same as that before coating, but the cycle life and DCR will be improved.

[0022] Preferably, the outer shell layer comprises any one or a combination of at least two of the following: oxides (e.g., B2O3, Al2O3, TiO2, Y2O3, CeO2, MgO, etc.), fluorides (e.g., AlF3, LiF, CeF3, MgF2, etc.), or phosphates (e.g., Li3PO4, AlPO4, etc.).

[0023] Preferably, in the porous high-nickel ternary cathode material, the content of the outer shell layer is within 0.5 wt%, for example, it can be 0.5 wt%, 0.4 wt%, 0.3 wt%, 0.2 wt%, 0.1 wt%, or 0.05 wt%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 0.05% to 0.5%.

[0024] Secondly, the present invention provides a method for preparing a porous high-nickel ternary cathode material as described in the first aspect, the method comprising the following steps:

[0025] The precursor material, lithium source, first pore-forming agent and second pore-forming agent are mixed and calcined to obtain the porous high-nickel ternary cathode material;

[0026] The second pore-forming agent includes any one or a combination of at least two of boric acid, boron oxide, phosphoric acid, oxide of M, sulfide of M, or acid salt of M, wherein M includes any one or a combination of at least two of W, Nb, Ta, Mo, or Sb.

[0027] In this invention, a first pore-forming agent and a second pore-forming agent are added simultaneously during firing. The first pore-forming agent is easily decomposed to generate gas or is easily volatile, thereby achieving pore formation. The second pore-forming agent has low solubility in the precursor material and can only accumulate on the surface, which can inhibit particle growth and coalescence. Due to the volatilization of the gas generated by the first pore-forming agent, the second pore-forming agent will not block the pores and will inherit the porous morphology formed by the first pore-forming agent. At the same time, the second pore-forming agent can form a substance with good ionic conductivity with the material, further improving the ionic conductivity of the material, and finally accumulating on the surface of the matrix to form the porous coating layer.

[0028] If the second pore-forming agent is added during the second calcination but not during the first calcination, on the one hand, some of the pores created by the first pore-forming agent will close during the calcination process; on the other hand, if the second pore-forming agent is added during the second calcination, it will block the pores created by the first pore-forming agent, ultimately preventing both the matrix and the coating layer from having a porous structure.

[0029] Preferably, the second pore-forming agent comprises any one or a combination of at least two of boric acid, boron oxide, or phosphoric acid.

[0030] The second pore-forming agent of the present invention is preferably any one or a combination of at least two of boric acid, boron oxide, or phosphoric acid. Compared with other second pore-forming agents, it not only has lower solubility in the precursor material, but also has a lower melting point. It is easy to uniformly fuse and coat the material surface during sintering. Although other second pore-forming agents can inhibit particle growth and coalescence and inherit porous morphology, their effect is not as good as any one or a combination of at least two of boric acid, boron oxide, or phosphoric acid. Moreover, their melting point is not low, and they cannot guarantee uniform coating on the material surface.

[0031] Preferably, the first pore-forming agent comprises any one or a combination of at least two of ammonium dihydrogen phosphate, aluminum sulfate, or lithium sulfate.

[0032] Preferably, the total molar amount of the first pore-forming agent and the second pore-forming agent is less than 10 mol% of the precursor material, for example, it can be 10 mol%, 9 mol%, 8 mol%, 7 mol%, 6 mol%, 5 mol%, 4 mol%, 3 mol%, 2 mol%, or 1 mol%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable, preferably 0.2 to 10 mol%.

[0033] The total amount of the first pore-forming agent and the second pore-forming agent in this invention is preferably below 10 mol%. If it is too much, it will produce large pores and cause poor circulation performance. If it is too little, the pore-forming and coating effects will decrease.

[0034] Preferably, the molar ratio of the first pore-forming agent to the second pore-forming agent is (1-5):(1-5), for example, it can be 1:1, 1:3, 3:1, 1:5 or 5:1, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0035] The first pore-forming agent and the second pore-forming agent of the present invention can be combined in any proportion, preferably in the above molar ratio. If the first pore-forming agent is too little and the second pore-forming agent is relatively too much, the amount of pores formed will be insufficient, resulting in a low capacity. If the first pore-forming agent is too much and the second pore-forming agent is relatively too little, the pores formed will close, thereby affecting the capacity.

[0036] Preferably, the calcination temperature is 500-800℃, for example, 500℃, 600℃, 700℃ or 800℃, but not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0037] Preferably, the calcination time is 3 to 25 hours, for example, 3 hours, 5 hours, 10 hours, 15 hours, 20 hours or 25 hours, but not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0038] Preferably, the calcination is carried out in an oxygen atmosphere.

[0039] Preferably, the calcination process does not involve washing.

[0040] The present invention allows for elemental doping of the residual first pore-forming agent without washing after calcination.

[0041] Preferably, the calcination process is further followed by an outer shell coating treatment.

[0042] Preferably, the temperature for the outer shell coating treatment is 200–800°C, for example, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C, or 800°C, and the time is 3–15 hours, for example, 3 hours, 5 hours, 10 hours, or 15 hours, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0043] Preferably, the ratio of the molar amount of lithium ions in the lithium source to the total metal ions in the precursor material is (0.9 to 1.5):1, for example, it can be 0.9:1, 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1 or 1.5:1, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0044] Preferably, the precursor material includes Ni. a Co b Mn 1-a-b (OH)2, where 0.9 ≤ a < 1, for example, it can be 0.9, 0.91, 0.92, 0.93, 0.94, 0.95 or 0.96, and 0 < b ≤ 0.05, for example, it can be 0.01, 0.02, 0.03, 0.04 or 0.05, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0045] Thirdly, the present invention provides a lithium-ion battery comprising the porous high-nickel ternary cathode material as described in the first aspect.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] The porous high-nickel ternary cathode material of the present invention includes a substrate and a coating layer, both of which are porous structures with pores uniformly distributed within the material. This not only enhances the Li-Nickel content but also... + The diffusion rate is increased, the specific capacity is improved, and the porous structure can alleviate the mechanical stress caused by phase transition during charging and discharging, thereby improving the cycle performance of the porous high-nickel ternary cathode material; furthermore, the coating elements in the coating layer can further improve the ionic conductivity of the material, thereby further improving the electrochemical performance of the material. Detailed Implementation

[0048] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0049] Example 1

[0050] This embodiment provides a porous high-nickel ternary cathode material, which includes a substrate and a coating layer on the surface of the substrate, both of which have porous structures;

[0051] The matrix includes LiNi 0.92 Co 0.025 Mn 0.055 O2, wherein the coating layer comprises lithium phosphate, and the content of the coating layer is 2 wt%;

[0052] The preparation method of the porous high-nickel ternary cathode material includes the following steps:

[0053] The precursor material, lithium hydroxide, first pore-forming agent and second pore-forming agent are mixed and then calcined at 650°C for 15 hours in an oxygen atmosphere to obtain the porous high-nickel ternary cathode material.

[0054] The precursor material is Ni. 0.92 Co 0.025 Mn 0.055 (OH)2, wherein the molar ratio of lithium ions in the lithium hydroxide to the total metal ions in the precursor material is 1.1:1;

[0055] The first pore-forming agent is lithium sulfate, the second pore-forming agent is phosphoric acid, the total molar amount of the first pore-forming agent and the second pore-forming agent is 6 mol% of the precursor material, and the molar ratio of the first pore-forming agent and the second pore-forming agent is 1:1.

[0056] Example 2

[0057] This embodiment provides a porous high-nickel ternary cathode material. Except for the preparation method in which the molar ratio of the first pore-forming agent and the second pore-forming agent is 1:2, so that the porous high-nickel ternary cathode material can adapt to changes, the rest of the porous high-nickel ternary cathode material is the same as in Embodiment 1.

[0058] Example 3

[0059] This embodiment provides a porous high-nickel ternary cathode material. Except for the preparation method in which the second pore-forming agent is boric acid and the molar ratio of the first pore-forming agent to the second pore-forming agent is 1:2, so that the obtained porous high-nickel ternary cathode material adapts to changes, the rest is the same as in Embodiment 1.

[0060] Example 4

[0061] This embodiment provides a porous high-nickel ternary cathode material. Except for the preparation method in which the second pore-forming agent is tungsten oxide and the molar ratio of the first pore-forming agent to the second pore-forming agent is 1:2, so that the obtained porous high-nickel ternary cathode material adapts to changes, the rest is the same as in Embodiment 1.

[0062] Example 5

[0063] This embodiment provides a porous high-nickel ternary cathode material. Except for the preparation method in which the calcined material is mixed with boric acid after calcination and then calcined at 300°C for 8 hours in an oxygen atmosphere to change the adaptability of the obtained porous high-nickel ternary cathode material, the rest is the same as in Example 1.

[0064] Example 6

[0065] This embodiment provides a porous high-nickel ternary cathode material, which includes a substrate and a coating layer on the surface of the substrate, both of which have porous structures;

[0066] The matrix includes LiNi 0.9 Co 0.05 Mn 0.05 O2, wherein the coating layer comprises lithium phosphate, and the content of the coating layer is 0.02 wt%;

[0067] The preparation method of the porous high-nickel ternary cathode material includes the following steps:

[0068] The precursor material, lithium hydroxide, first pore-forming agent and second pore-forming agent are mixed and then calcined at 500°C for 25 hours in an oxygen atmosphere to obtain the porous high-nickel ternary cathode material.

[0069] The precursor material is Ni. 0.9 Co 0.05 Mn 0.05 (OH)2, wherein the molar ratio of lithium ions in the lithium hydroxide to the total metal ions in the precursor material is 1.5:1;

[0070] The first pore-forming agent is lithium sulfate, the second pore-forming agent is phosphoric acid, the total molar amount of the first pore-forming agent and the second pore-forming agent is 0.2 mol% of the precursor material, and the molar ratio of the first pore-forming agent and the second pore-forming agent is 5:1.

[0071] Example 7

[0072] This embodiment provides a porous high-nickel ternary cathode material, which includes a substrate and a coating layer on the surface of the substrate, both of which have porous structures;

[0073] The matrix includes LiNi 0.92 Co 0.025 Mn 0.055 O2, wherein the coating layer comprises lithium phosphate, and the content of the coating layer is 5.6 wt%;

[0074] The preparation method of the porous high-nickel ternary cathode material includes the following steps:

[0075] The precursor material, lithium hydroxide, first pore-forming agent and second pore-forming agent are mixed and then calcined at 800°C for 3 hours in an oxygen atmosphere to obtain the porous high-nickel ternary cathode material.

[0076] The precursor material is Ni. 0.92 Co 0.025 Mn 0.055(OH)2, wherein the molar ratio of lithium ions in the lithium hydroxide to the total metal ions in the precursor material is 1:1;

[0077] The first pore-forming agent is lithium sulfate, the second pore-forming agent is phosphoric acid, the total molar amount of the first pore-forming agent and the second pore-forming agent is 10 mol% of the precursor material, and the molar ratio of the first pore-forming agent and the second pore-forming agent is 1:5.

[0078] Example 8

[0079] This embodiment provides a porous high-nickel ternary cathode material. Except for the preparation method in which the total molar amount of the first pore-forming agent and the second pore-forming agent is 13 mol% of the precursor material, so that the obtained porous high-nickel ternary cathode material can adapt to changes, the rest is the same as in Example 1.

[0080] Example 9

[0081] This embodiment provides a porous high-nickel ternary cathode material. Except for the preparation method in which the total molar amount of the first pore-forming agent and the second pore-forming agent is 0.01 mol% of the precursor material, so that the obtained porous high-nickel ternary cathode material adapts to changes, the rest is the same as in Example 1.

[0082] Example 10

[0083] This embodiment provides a porous high-nickel ternary cathode material. Except for the preparation method in which the molar ratio of the first pore-forming agent and the second pore-forming agent is 1:8, so that the porous high-nickel ternary cathode material can adapt to changes, the rest of the porous high-nickel ternary cathode material is the same as in Embodiment 1.

[0084] Example 11

[0085] This embodiment provides a porous high-nickel ternary cathode material. Except for the preparation method in which the molar ratio of the first pore-forming agent and the second pore-forming agent is 8:1, so that the porous high-nickel ternary cathode material can adapt to changes, the rest of the porous high-nickel ternary cathode material is the same as in Embodiment 1.

[0086] Comparative Example 1

[0087] This comparative example provides a high-nickel ternary cathode material. Except for the fact that the first and second pore-forming agents are not added in the preparation method, which causes the porous high-nickel ternary cathode material to change its adaptability, the high-nickel ternary cathode material is otherwise the same as in Example 1.

[0088] Comparative Example 2

[0089] This comparative example provides a high-nickel ternary cathode material. Except for the fact that no second pore-forming agent is added in its preparation method, which results in a porous high-nickel ternary cathode material with adaptability changes, the high-nickel ternary cathode material is otherwise the same as in Example 1.

[0090] Comparative Example 3

[0091] This comparative example provides a high-nickel ternary cathode material. Except for the fact that the first pore-forming agent was not added in its preparation method, which resulted in a porous high-nickel ternary cathode material with adaptability changes, the high-nickel ternary cathode material is otherwise the same as in Example 1.

[0092] Comparative Example 4

[0093] This comparative example provides a high-nickel ternary cathode material. Except for the fact that no second pore-forming agent is added in its preparation method, but the calcined material and the second pore-forming agent are calcined again at 300°C for 8 hours in an oxygen atmosphere to change the adaptability of the resulting porous high-nickel ternary cathode material, the rest is the same as in Example 1.

[0094] The pore size and porosity of the cathode materials in the above embodiments and comparative examples are shown in Table 1. The cathode materials in the above embodiments and comparative examples are used to prepare cathode plates, which are then used with lithium plates, polypropylene separators, and lithium hexafluorophosphate electrolyte to prepare lithium-ion batteries. The prepared lithium-ion batteries are subjected to electrochemical performance testing under the following conditions: voltage range of 2.8-4.3V, 0.1C. The test results are shown in Table 1.

[0095] Table 1

[0096]

[0097]

[0098] As can be seen from Table 1:

[0099] As can be seen from Examples 1 and Comparative Examples 1-3, the cathode material of Comparative Example 1 is not porous and has no surface coating, resulting in a significant decrease in performance compared to Example 1. Even with the addition of the first or second pore-forming agent in Comparative Examples 2-3, although the material performance is improved compared to Comparative Example 1, it is still significantly lower than that of Example 1. As can be seen from Examples 1 and Comparative Example 4, both the matrix and the coating layer of the present invention have porous structures. If the second pore-forming agent is added only during the second calcination, the structure of the material of the present invention cannot be obtained, and the performance of the obtained material is lower than that of Example 1. As can be seen from Examples 1-3 and Example 4, the coating layer in the cathode material of Example 4 of the present invention is tungsten oxide. Tungsten oxide has a relatively high melting point compared to... Boric acid, boron oxide, or phosphoric acid cannot uniformly coat the material surface; therefore, the performance of Example 4 is lower than that of Examples 1-3. As can be seen from Examples 1 and 5, the present invention further coats the material with boric acid after one firing, which can further improve the cycling performance of the material. As can be seen from Examples 1 and Examples 8-9, the total amount of the first pore-forming agent and the second pore-forming agent added will affect the pore size, porosity, and coating content of the material, and it is preferable to add them within a reasonable range. As can be seen from Examples 1 and Examples 10-11, the molar ratio of the first pore-forming agent and the second pore-forming agent will also affect the pore size, porosity, and coating content of the material, and it is preferable that the two are within a suitable molar ratio.

[0100] The above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A porous high-nickel ternary cathode material, characterized in that, The porous high-nickel ternary cathode material includes a substrate and a coating layer on the surface of the substrate, both of which are porous structures; The matrix includes LiNi a Co b Mn 1-a-b-c O2, where 0.9 ≤ a < 1, 0 < b ≤ 0.07; The coating element in the coating layer includes any one or a combination of at least two of B, P, W, Nb, Ta, Mo, or Sb.

2. The porous high-nickel ternary cathode material according to claim 1, characterized in that, The porous high-nickel ternary cathode material has a pore size of 1–13 nm, preferably 2–4 nm; Preferably, the porosity of the porous high-nickel ternary cathode material is 30% to 90%, and more preferably 40% to 60%. Preferably, in the porous high-nickel ternary cathode material, the content of the coating layer is within 9.0 wt%, and more preferably 0.02 to 5.6 wt%.

3. The porous high-nickel ternary cathode material according to claim 1 or 2, characterized in that, The matrix also includes doping elements, which include any one or a combination of at least two of P, S or Al. Preferably, the coating elements in the coating layer include B and / or P; Preferably, the coating layer comprises lithium borate and / or lithium phosphate.

4. The porous high-nickel ternary cathode material according to any one of claims 1-3, characterized in that, The porous high-nickel ternary cathode material also includes an outer shell layer, which is located on the surface of the coating layer away from the substrate. Preferably, the outer shell layer comprises any one or a combination of at least two of oxides, fluorides, or phosphates; Preferably, the oxide comprises any one or a combination of at least two of B2O3, Al2O3, TiO2, Y2O3, CeO2, or MgO; Preferably, the fluoride comprises any one or a combination of at least two of AlF3, LiF, CeF3, or MgF2; Preferably, the phosphate comprises Li3PO4 and / or AlPO4; Preferably, in the porous high-nickel ternary cathode material, the content of the outer shell layer is less than 0.5 wt%.

5. A method for preparing a porous high-nickel ternary cathode material as described in any one of claims 1-4, characterized in that, The preparation method includes the following steps: The precursor material, lithium source, first pore-forming agent and second pore-forming agent are mixed and calcined to obtain the porous high-nickel ternary cathode material; The second pore-forming agent includes any one or a combination of at least two of boric acid, boron oxide, phosphoric acid, oxide of M, sulfide of M, or acid salt of M, wherein M includes any one or a combination of at least two of W, Nb, Ta, Mo, or Sb.

6. The preparation method according to claim 5, characterized in that, The second pore-forming agent includes any one or a combination of at least two of boric acid, boron oxide, or phosphoric acid; Preferably, the first pore-forming agent comprises any one or a combination of at least two of ammonium dihydrogen phosphate, aluminum sulfate, or lithium sulfate; Preferably, the total molar amount of the first pore-forming agent and the second pore-forming agent is less than 10 mol% of the precursor material, and more preferably 0.2 to 10 mol%. Preferably, the molar ratio of the first pore-forming agent to the second pore-forming agent is (1-5):(1-5).

7. The preparation method according to claim 5 or 6, characterized in that, The calcination temperature is 500–800℃; Preferably, the calcination time is 3 to 25 hours; Preferably, the calcination is carried out in an oxygen atmosphere.

8. The preparation method according to any one of claims 5-7, characterized in that, No washing is performed after calcination; Preferably, the calcination process is further followed by an outer shell coating treatment; Preferably, the temperature for the outer shell coating treatment is 200–800°C, and the time is 3–15 hours.

9. The preparation method according to any one of claims 5-8, characterized in that, The molar ratio of lithium ions in the lithium source to the total metal ions in the precursor material is (0.9–1.5):1; Preferably, the precursor material includes Ni. a Co b Mn 1-a-b (OH)2, where 0.9≤a<1, 0<b≤0.

05.

10. A lithium-ion battery, characterized in that, The lithium-ion battery includes the porous high-nickel ternary cathode material as described in any one of claims 1-4.

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