CN-122025742-A - Low-temperature ultrahigh-rate sodium ion battery and preparation method thereof

CN122025742ACN 122025742 ACN122025742 ACN 122025742ACN-122025742-A

Abstract

The invention relates to a low-temperature ultrahigh-rate sodium ion battery and a preparation method thereof. The sodium ion lithium battery comprises an anode plate, a cathode plate, a ceramic coating diaphragm and electrolyte, wherein the anode plate consists of an anode current collector, an anode active substance, a binder and a conductive agent, the cathode plate consists of a cathode current collector, a cathode active substance, a binder and a conductive agent, and the electrolyte consists of a solvent, sodium salt and a functional additive. The preparation method provided by the invention is used for preparing the low-temperature ultrahigh-rate sodium ion battery by scientific proportioning design and optimization of the positive and negative electrode formula systems and the core process. The sodium ion battery can support low-temperature-40 ℃ discharge, 150 ℃ high-current instantaneous discharge and has good cycle performance. The problem of performance attenuation of the conventional sodium ion battery under the dual severe conditions of low temperature and ultra-high multiplying power is systematically solved.

Inventors

YANG YUEKUN
HUANG WANRONG
WANG HONGMEI
WANG HAO
HUANG YONGQI
Qu qinghua
GUO XU
WU AISHEN

Assignees

佛山市实达科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260122

Claims (10)

1. A sodium ion battery is characterized by comprising a positive electrode plate, a negative electrode plate, a ceramic coating diaphragm and electrolyte, wherein the positive electrode plate consists of a positive electrode current collector, a positive electrode active substance, a binder and a conductive agent, the negative electrode plate consists of a negative electrode current collector, a negative electrode active substance, a binder and a conductive agent, and the electrolyte consists of a solvent, sodium salt and a functional additive.
2. The sodium ion battery according to claim 1, wherein the positive electrode active material is at least one selected from layered oxides, polyanion compounds and Prussian blue as an organic positive electrode material, preferably, the positive electrode active material has a gram capacity of 80-160 mAh/g, a particle diameter D 10 of 1-4 μm, a particle diameter D 50 of 4-9 μm, a particle diameter D 90 of 9-15 μm, a particle size distribution width of 1.2-5 and a specific surface area of 0.3-11 m 2 /g.
3. The sodium ion battery according to claim 1, wherein the negative electrode active material is hard carbon, preferably the negative electrode active material has a gram capacity of 260 to 290mAh/g, a particle diameter D 10 of 1 to 3 μm, a D 50 of 4 to 13 μm, a D 90 of 13 to 20 μm, a particle size distribution width of 1.2 to 6.0, and a specific surface area of 9 to 20m 2 /g.
4. The sodium ion battery of claim 1, wherein the binder is selected from at least one of polyvinylidene fluoride, sodium carboxymethyl cellulose, styrene butadiene rubber, polyacrylic acid, polyacrylonitrile and polymers, sodium alginate, polyimide, polyethylene oxide, polystyrene sulfonate.
5. The sodium ion battery of claim 1, wherein the conductive agent is at least one selected from ketjen black, compression ratio conductive agent, conductive carbon black, carbon nanotubes, graphene, carbon nanofibers, superconducting carbon black.
6. The sodium ion battery of claim 1, wherein the ceramic coating membrane has a thickness of 10-20 μm, a porosity of 45-60%, a tensile strength of greater than 190Mpa, a puncture strength of greater than 200gf, an air permeability of 80-250 s/100mL, and a thermal shrinkage of less than 5.0%.
7. The sodium ion battery according to claim 1, wherein the solvent comprises a cyclic carbonate and/or a chain carbonate, preferably the cyclic carbonate is selected from at least one of ethylene carbonate, ethylene sulfate, propylene carbonate, preferably the chain carbonate is selected from at least one of dimethyl carbonate, methylethyl carbonate, propane sultone, diethyl carbonate, ethyl propionate, and carbonate.
8. The sodium ion battery of claim 1, wherein the functional additive is one or more of vinylene carbonate and fluoroethylene carbonate, organic phosphide, organic fluoride, fluoroalkyl phosphate, sodium difluorooxalate borate, fluoroethylene carbonate and tris (trimethylsilyl) phosphite, dimethyl sulfoxide and ethyl difluoroacetate.
9. A method of producing a sodium ion battery according to any one of claims 1 to 8, comprising: 1) Respectively preparing an anode plate, a cathode plate, a ceramic coating diaphragm and electrolyte; 2) And assembling, forming and capacity-dividing the prepared positive pole piece, negative pole piece, ceramic coating diaphragm and electrolyte to prepare the sodium ion battery.
10. The preparation method according to claim 9, wherein the assembling comprises stacking the positive electrode plate, the negative electrode plate and the ceramic coating diaphragm by a Z-type lamination process, constructing a battery cell by multi-station ultrasonic welding, and injecting electrolyte after vacuum heat drying treatment of the battery cell.

Description

Low-temperature ultrahigh-rate sodium ion battery and preparation method thereof Technical Field The invention relates to the technical field of sodium ion batteries, in particular to a low-temperature ultrahigh-rate sodium ion battery and a preparation method thereof. Background The lithium ion battery has been widely used in various fields such as new energy automobiles, energy storage systems, portable electronic devices, and the like by virtue of the advantages of high energy density, long cycle life, and the like. However, the lithium ion battery has two core limitations in practical application, and restricts the large-scale popularization of the lithium ion battery in more scenes. On one hand, the lithium ion battery has strict requirements on the charging and discharging voltage range, the overcharge or overdischarge behaviors can cause permanent damage to the battery, the battery is characterized in that the battery capacity is irreversibly reduced, the cycle life is obviously shortened, potential safety hazards such as thermal runaway, combustion and even explosion can be possibly caused when the battery is more serious, the management and control difficulty and the safety risk in the use process of the battery are increased, on the other hand, the core raw materials (such as cobalt, lithium and the like) of the lithium ion battery are scarce in reserves and expensive, and the production process is complex and the flow is complex, so that the manufacturing cost of the lithium ion battery is high, and the application requirements of the price sensitive fields such as large-scale energy storage, low-cost walking tools and the like are difficult to meet. In order to overcome the defects of the lithium ion battery, scientific researchers gradually aim at the sodium ion battery, and the scientific researchers have become an important supplementary technical route of the lithium ion battery by virtue of the intrinsic properties and performance characteristics of resources. The sodium ion battery has the core advantages of being rich in resources, controllable in cost, far higher than lithium in storage of sodium element in earth crust, free of depending on rare metals such as cobalt, low in raw material acquisition difficulty, stable in price, expected to achieve lower manufacturing cost by matching with a relatively simplified production process, better in safety, wider in electrochemical window of the sodium ion battery, better in overcharge and overdischarge resistances than the lithium ion battery, remarkably reduced in safety risk, prominent in low-temperature performance, wider in use temperature range of the sodium ion battery, particularly remarkable in performance stability advantage in a low-temperature environment, capable of effectively relieving the industry point of low-temperature performance attenuation of the power battery at-20 ℃, capable of covering-40-60 ℃ in an overall working temperature range (capable of stably working at the conventional rate), and capable of being widely adapted to extreme environments compared with the conventional-20-55 ℃ working temperature range of the lithium ion battery. Based on the advantages, the sodium ion battery has huge application potential in the scenes of cold region equipment, outdoor energy storage, low-temperature starting power supply and the like, the conventional quick charge performance and low-temperature adaptability of the battery pack can be further improved by adopting the sodium ion battery to replace the lithium ion battery, and along with the promotion of industrialization progress, the cost advantage of the sodium ion battery is further highlighted. Although the sodium ion battery has a plurality of advantages, the problems of discharge performance attenuation and insufficient ultrahigh-rate discharge capacity in a low-temperature environment severely restrict the industrial application of the sodium ion battery in the high-end fields such as new energy automobiles, large-scale energy storage systems, high-latitude cold region special equipment and the like. From the electrochemical mechanism, the ionic conductivity of the electrolyte is obviously reduced under the low-temperature condition, meanwhile, the impedance of the interface between the electrode and the electrolyte is sharply increased, the two factors jointly lead to the rapid reduction of the battery capacity and the deterioration of the multiplying power performance, particularly, the ionic migration rate of the electrolyte is greatly reduced under the extremely low-temperature environment of-40 ℃, and the charge transfer impedance of the electrode/electrolyte interface is exponentially increased, so that the ultrahigh-rate discharge capacity of the sodium ion battery is directly reduced, and the special requirements of the high-latitude cold region on the rapid starting of equipment and the instant discharging of 150C heavy current cannot be met, such as the scenes of