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CN-122025436-A - Carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor and preparation method thereof

CN122025436ACN 122025436 ACN122025436 ACN 122025436ACN-122025436-A

Abstract

The invention provides a carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor and a preparation method thereof, and belongs to the technical field of lithium ion capacitors. The capacitor comprises a positive pole piece, a negative pole piece, a current collector, a diaphragm and electrolyte, wherein the positive pole adopts a high-nickel monocrystal material and active carbon composite system and is internally provided with a pre-lithiation material, and the negative pole adopts carbon-coated titanium niobium oxide. The energy density reaches 30-130 Wh/kg, the power density reaches 3-10 kW/kg, the performance blank of the traditional super capacitor and the lithium ion battery is filled, the working voltage is 1.5-2.8V, the storage and transportation can be carried out after the discharge is carried out to 0V, the lengthy formation process is omitted, and the production period is shortened to 15 days. The invention realizes multiple breakthroughs of energy, power, safety and production efficiency, is suitable for high-requirement hybrid energy storage scenes, and has high practical value and industrialization prospect.

Inventors

  • ZHANG ZHIWEI
  • HUANG HUA
  • DONG FEIFEI

Assignees

  • 深圳市华科领晨电子科技有限公司

Dates

Publication Date
20260512
Application Date
20260213

Claims (10)

  1. 1. The carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor is characterized by comprising a positive electrode plate, a negative electrode plate, a current collector, a diaphragm and electrolyte; The positive electrode material of the positive electrode plate comprises, by weight, 80-90% of a high-nickel monocrystal material, 5-15% of active carbon, 1-5% of a solid electrolyte coating layer, 1-2% of a positive electrode conductive agent, 1.5-2.5% of a binder and 3-5% of a pre-lithiated material; The negative electrode material of the negative electrode plate comprises, by weight, 92-97wt% of carbon-coated titanium-niobium oxide, 1-3wt% of a negative electrode conductive agent and 1-2wt% of a negative electrode binder; the current collector is aluminum foil or corrosion aluminum foil; The membrane is a cellulose membrane or a cellulose composite membrane; The electrolyte comprises a solute LiPF 6 , a solvent and an additive, wherein in the electrolyte, the concentration of LiPF 6 is 1.2-1.5M, and the additive is 1-5wt%.
  2. 2. The carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor of claim 1, wherein the high-nickel single crystal material in the positive electrode material comprises LiNi 0.8 Co 0.1 Mn 0.1 O 2 , and the specific surface area of the activated carbon is more than or equal to 2000m 2 /g; The solid electrolyte coating layer is formed by coating precursors, the coating precursors are Li 3 PO 4 or LiAlO 2 , the conductive agent is acetylene black or single-walled carbon nanotubes, and the binder comprises polyvinylidene fluoride; The pre-lithiated material includes Li 5 FeO 4 or Li 2 Cu 2 O 4 .
  3. 3. The carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor of claim 1, wherein the particle size of the carbon-coated titanium-niobium oxide in the negative electrode material is 50-200 nm, the negative electrode conductive agent comprises acetylene black, and the negative electrode binder comprises sodium alginate; The titanium niobium oxide includes TiNb 2 O 7 .
  4. 4. The carbon-coated titanium niobium oxide negative electrode lithium ion capacitor of claim 1, wherein the electrolyte is one or more of dimethyl carbonate, ethylene carbonate and ethylmethyl carbonate, and the additive comprises LiBF 4 , liBOB, tris (trimethylsilyl) phosphite and lidaob.
  5. 5. The method for manufacturing a carbon-coated titanium niobium oxide negative electrode lithium ion capacitor according to any one of claims 1 to 4, comprising the steps of: Step 1), under the stirring condition, mixing and dispersing a high-nickel monocrystal material, active carbon, a pre-lithiation material and N-methyl pyrrolidone, mixing the mixture with a coating precursor dispersion liquid, and sequentially drying, heat treatment and crushing to obtain a coating composite anode material; Step 2), mixing the obtained coated composite anode material, an anode conductive agent, a binder and N-methyl pyrrolidone, dispersing to obtain anode slurry, coating the obtained anode slurry on the surface of an aluminum foil, and drying, rolling and cutting to obtain an anode sheet; Step 3), mixing and dispersing the carbon-coated titanium niobium oxide, the conductive agent and the binder solution to obtain negative electrode slurry, coating the negative electrode slurry on the surface of an aluminum foil, and drying, rolling and slitting to obtain a negative electrode plate; and 4) winding or laminating the positive pole piece, the diaphragm and the negative pole piece in sequence, loading the positive pole piece, the diaphragm and the negative pole piece into a cylindrical steel shell with all lugs, vacuum drying, injecting electrolyte, sequentially carrying out pre-lithiation treatment and zero-volt treatment, and sealing to obtain the carbon-coated titanium-niobium oxide negative lithium ion capacitor.
  6. 6. The method for preparing a carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor according to claim 5, wherein in the step 1), the stirring speed of the stirring condition is 2000-2500 rpm, and the dispersing time is 20-40 min; The mixing with the coating precursor dispersion liquid is carried out under the stirring condition, the stirring speed is 1800-2200 rpm, and the stirring time is 50-70 min; the drying temperature is 60-80 ℃, and the drying time is 10-15 h; the temperature of the heat treatment is 500-600 ℃, the time of the heat treatment is 3-5 h, and the temperature rising rate from room temperature to the heat treatment temperature is 3-5 ℃ per minute.
  7. 7. The method for producing a carbon-coated titanium niobium oxide negative electrode lithium ion capacitor according to claim 5 or 6, wherein in step 1), the solvent of the coating precursor dispersion liquid is N-methylpyrrolidone; In the step 2), the solvent of the binder solution is N-methyl pyrrolidone, the drying temperature is 70-150 ℃, and the drying time is 30-40 min.
  8. 8. The method for preparing a carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor according to claim 7, wherein in the step 3), the dispersing speed is 800-1200 rpm, and the dispersing time is 100-120 min; The temperature of the drying is 70-150 ℃, and the drying time is 30-40 min.
  9. 9. The method for preparing a carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor according to claim 5, wherein in the step 4), the vacuum drying temperature is 100-150 ℃ and the drying time is 20-30 hours; The injection of the electrolyte is performed in an inert atmosphere.
  10. 10. The method for preparing the carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor according to claim 5, wherein in the step 4), the pre-lithiation treatment is a stepwise constant current charging method, and the method comprises three stages, wherein the first stage is charged to 2.4V at 0.02-0.03 c for 30-40 min, the second stage is charged to 2.8V at 0.05-0.07 c for 30-40 min, and the third stage is charged to 3.0V at 0.1-1.2 c for 3.0V for 1-1.2 h.

Description

Carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor and preparation method thereof Technical Field The invention relates to the technical field of lithium ion capacitors, in particular to a carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor and a preparation method thereof. Background The lithium ion capacitor has the high power density (1-15 kW/kg) of the super capacitor and the high energy density (15-130 Wh/kg) of the lithium ion battery, so that the lithium ion capacitor becomes a novel core energy storage component in the fields of intelligent furniture, the Internet of things, the start and stop of new energy automobiles, novel power frequency modulation and the like, and related industries are also widely developed. Generally, lithium ion capacitors are mainly classified into two types, namely a positive electrode is made of a porous carbon material (such as active carbon), a negative electrode is made of a graphite carbon material (such as graphite, soft carbon, hard carbon and the like), related products (patent publication No. CN102969162A, CN101138058A, CN109817472B, CN 104701031B) have a typical working voltage range (2.2-3.8V), relatively low Energy density (9-20 Wh/kg), high power density (3-15 kW/kg), extremely long cycle life (cycle life is greater than or equal to 100 ten thousand times), relatively wide working temperature (-40-65 ℃) and the like, however, due to the construction mechanism of a positive and negative electrode material system, the system still has the characteristics of low Energy density, high large-scale manufacturing cost (5000-30000 yuan/kWh), long manufacturing period (generally more than 45 days), high safety risk of large-scale manufacturing process (most products, pre-lithiation treatment of metal lithium on engineering technology, high potential safety hazards exist), and the like, so that large-scale manufacturing and popularization of the products are limited, and the main manufacturing and popularization of the type are mainly reported by the system, and the current JM (Energy, the current manufacturing unit is in the sea, and the Energy is in the sea, and the Energy is induced by the sea. Meanwhile, under the development of novel energy storage materials, a high specific energy type lithium ion capacitor (patent publication No. CN106847520A, CN106601489B, CN105047428B, CN 107910197B) which takes active carbon, lithium-rich metal oxide, nickel cobalt lithium manganate and other composite materials as an anode, soft carbon or hard carbon or the composite materials thereof as a cathode is rapidly developed, and has the typical characteristics of 4.0-2.5V working voltage interval, 30-130 Wh/kg energy density, 1-5 kW/kg power density, 25-ten thousand cycle life and the like, and particularly has the advantages of low electricity cost (close to a power type lithium ion battery) and short production period (7-15 days), so that the type of lithium ion capacitor is rapidly developed and applied. However, with the large-scale manufacturing and application of the lithium ion capacitor, the lithium ion capacitor still has the defects of high manufacturing cost, easy lithium precipitation of the negative electrode, and the necessity of charged storage and transportation (zero volt storage and transportation cannot be realized) due to the use of the negative electrode carbon material and the negative electrode copper foil current collector, so that the further large-scale application of the energy storage device is greatly limited. After being first proposed by Goodenough professor team, the titanium niobium oxide TiNb 2O7 as a novel electrode material shows excellent multiplying power characteristics and very stable cycle performance, and meanwhile, the titanium niobium oxide TiNb 2O7 has the advantages of no SEI film formation and high intercalation-deintercalation lithium potential (1.2-1.6V vs Li +/Li) and becomes one of novel candidate materials of a lithium ion capacitor. Patent publication No. CN105575675A describes a related description of a method for preparing a titanium-niobium composite oxide by a water/solvent thermal method and application of the titanium-niobium composite oxide in a lithium ion super capacitor, and mainly describes a preparation process of the titanium-niobium composite oxide. Patent publication No. CN 117373836A refers to the introduction of a two-layer negative electrode sheet and a hybrid supercapacitor comprising the same, and is mainly described as an electrode with one layer of active carbon and one layer of titanium-niobium oxide, but the description of constructing a novel lithium ion capacitor based on the titanium-niobium oxide as a negative electrode material is freshly reported. Disclosure of Invention The invention aims to provide a carbon-coated titanium-niobium oxide negative electrode lithium ion capacitor and a preparation method thereof, which are used for solving the techn