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DE-202026101372-U1 - Cathode foil, lithium-ion battery and power-consuming device

DE202026101372U1DE 202026101372 U1DE202026101372 U1DE 202026101372U1DE-202026101372-U1

Abstract

Cathode foil, characterized in that it comprises a cathode collector and a cathode material applied to the cathode collector, wherein the cathode material comprises an active cathode material, the active cathode material comprising a lithium manganese iron phosphate agglomerate and a ternary material, wherein the cathode foil fulfills the following: 0,004 ≤ a × b × c < 0,230, where a is a dimensionless peak area ratio of diffraction peaks of a (211) crystal plane to a (131) crystal plane in an XRD spectrum of the active cathode material; where b is a dimensionless mass fraction of Ni element in the active cathode material; and where c is a dimensionless mass ratio of the lithium-manganese-iron-phosphate agglomerate to the ternary material; where a chemical formula of the lithium manganese iron phosphate agglomerate LiMn x Fe 1-x PO 4 where 0 < x < 1.

Assignees

  • CALB GROUP CO LTD

Dates

Publication Date
20260513
Application Date
20260311
Priority Date
20250428

Claims (20)

  1. Cathode foil, characterized in that it comprises a cathode collector and a cathode material applied to the cathode collector, wherein the cathode material comprises an active cathode material, the active cathode material comprising a lithium manganese iron phosphate agglomerate and a ternary material, wherein the cathode foil fulfills the following: 0,004 ≤ a × b × c < 0,230, where a is a dimensionless peak area ratio of diffraction peaks of a (211) crystal plane to a (131) crystal plane in an XRD spectrum of the active cathode material; where b is a dimensionless mass fraction of Ni element in the active cathode material; and where c is a dimensionless mass ratio of the lithium manganese iron phosphate agglomerate to the ternary material; where a chemical formula of the lithium manganese iron phosphate agglomerate LiMn₂X₁Fe₁ -X₂PO₄ where 0 < x < 1.
  2. cathode foil according to Claim 1 , characterized in that the cathode foil satisfies the following: 0.044 ≤ a×b×c < 0.110.
  3. cathode foil according to Claim 1 , characterized in that a lies in a range from 0.04 to 0.99.
  4. cathode foil according to Claim 3 , characterized in that a lies in a range from 0.32 to 0.99.
  5. cathode foil according to Claim 1 , characterized in that b lies in a range from 0.004 to 0.440.
  6. cathode foil according to Claim 5 , characterized in that b lies in a range from 0.015 to 0.350.
  7. cathode foil according to Claim 1 , characterized in that c lies in a range from 0.010 to 99.000.
  8. cathode foil according to Claim 7 , characterized in that c lies in a range from 0.428 to 32.000.
  9. cathode foil according to Claim 1 , characterized in that the ternary material is selected from at least one of lithium nickel cobalt manganese oxide and lithium nickel cobalt aluminum oxide.
  10. cathode foil according to Claim 1 , characterized in that the lithium manganese iron phosphate agglomerate comprises a coating material, wherein the coating material comprises at least one of carbon, silicide and metal oxide.
  11. cathode foil according to Claim 10 , characterized in that the percentage mass content of the coating material in the lithium manganese iron phosphate agglomerate is 0 to 1%.
  12. cathode foil according to Claim 1 , characterized in that a particle size Dv50 of the lithium manganese iron phosphate agglomerate is 3 to 15 µm.
  13. cathode foil according to Claim 1 , characterized in that the chemical formula of the ternary material LiNi y Co z M (1-yz) O 2 is, where M is at least one of Mn, Al, where y is 0.2 to 0.95, where z is 0.01 to 0.25.
  14. cathode foil according to Claim 1 , characterized in that the ternary material comprises a coating material, wherein the coating material comprises at least one element of aluminium, titanium, tungsten, boron, phosphorus, cobalt, yttrium and silicon.
  15. cathode foil according to Claim 14 , characterized in that the percentage mass content of the coating material in the ternary material is 0 to 1%.
  16. cathode foil according to Claim 1 , characterized in that a particle size Dv50 of the ternary material is 1 to 20 µm.
  17. cathode foil according to Claim 1 , characterized in that the percentage mass content of the active cathode material in the cathode material is 80% to 98%.
  18. cathode foil according to Claim 1 , characterized in that the cathode material comprises a conductive agent and a binder, wherein the percentage by mass of the conductive agent in the cathode material is 0.1 to 5%, and wherein the percentage by mass of the binder in the cathode material is 0.1 to 5%.
  19. Lithium-ion battery, characterized in that it has a cathode foil according to one of the Claims 1 until 18 includes.
  20. Power-consuming device, characterized in that it uses a lithium-ion battery according to Claim 19 includes.

Description

Technical field The present invention relates to the technical field of batteries, in particular a cathode foil, a lithium-ion battery and a power-consuming device. Technical background Lithium manganese iron phosphate (LMFP) is an improved lithium iron phosphate material characterized by a high operating voltage range, large theoretical specific capacity, good thermal and chemical stability, broad availability, and low cost, making it one of the most important active cathode materials in research. LMFP agglomerates are secondary particles aggregated from a set of two or more primary particles and exhibiting an agglomerated state. Compared to non-agglomerated LMFP primary particles, the use of LMFP agglomerates can improve the solid-state transfer capacity of a cathode system, reduce battery impedance, and enhance kinetic performance. However, manganese dissolves in the LMFP agglomerates during charging and discharging, especially when the manganese content in the active cathode material is high. This leads to an increase in defects in the cathode material and oxidation of the electrolyte solution. This, in turn, makes the battery susceptible to gas production, which impairs its performance and safety. Therefore, it is necessary to develop a technology that reduces gas production from the LMFP agglomerate system. Content of the invention The purpose of the present invention is to provide a cathode foil, a lithium-ion battery and a power-consuming device by overcoming the above shortcomings in the prior art, so that a battery comprising the cathode foil has both low gas production and high safety performance. To achieve the above purpose, the present invention, according to a first aspect, provides a cathode foil comprising a cathode collector and a cathode material applied to the cathode collector, wherein the cathode material comprises an active cathode material, the active cathode material comprising a lithium manganese iron phosphate agglomerate and a ternary material, wherein the cathode foil fulfills the following: 0,004≤a×b×c<0,230, where a is a dimensionless peak area ratio of the diffraction peaks of a (211) crystal plane to a (131) crystal plane in an XRD spectrum of the active cathode material; where b is a dimensionless mass fraction of Ni element in the active cathode material; where c is a dimensionless mass ratio of the lithium-manganese-iron-phosphate agglomerate to the ternary material. According to a second aspect, the present invention provides a lithium-ion battery comprising a cathode foil as described above. According to a third aspect, the present invention provides a power-consuming device comprising a lithium-ion battery as described above. In comparison to the prior art, the present invention has the following effects: In the present invention, the LMFP agglomerate is mixed with the ternary material and the peak area ratio of the diffraction peaks of the (211) crystal plane to the (131) crystal plane in the XRD spectrum of the active cathode material, the mass fraction of the Ni element in the active cathode material and the mass ratio of the lithium manganese iron phosphate agglomerate to the ternary material are controlled such that they satisfy a certain relationship, so that the cathode foil can significantly reduce gas production after application in a battery, thereby simultaneously ensuring that the battery has a high safety performance. Description of embodiments The technical solution in the embodiments of the present invention is explained clearly and completely below, so that the purpose, the technical solutions, and the advantages of the embodiments of the present invention become clearer. Obviously, the described embodiments do not represent all embodiments, but only a subset of the embodiments of the present invention. All other embodiments that a person skilled in the art in this field could obtain from the embodiments in the present invention without any creative work should be considered to be covered by the scope of protection of the present invention. The present invention includes, among the technical features described in an open manner, a closed technical solution with the listed features, and also an open technical solution with the listed features. Within the scope of the present invention, a numerical interval is considered continuous within said numerical interval unless otherwise specified, and includes a minimum and a maximum value of the range, as well as each value between these minimum and maximum values. If the range refers to an integer, every integer between the minimum and maximum values of the range is included. If several ranges are specified to describe a feature or property, the ranges may also be combined. In other words, unless otherwise specified, all ranges disclosed herein are to be understood as encompassing all subranges contained therein. The specific dispersion and mixing treatments are not specifically limited within the scope of the