CN-121642061-B - Three-phase composite solid electrolyte material and solid oxide fuel cell with same

Abstract

The invention discloses a three-phase composite solid electrolyte material and a solid oxide fuel cell with the same, and belongs to the technical field of solid oxide fuel cells, wherein the electrolyte material comprises BZCY, naAlO 2 and NaOH, the mass ratio of BZCY to NaAlO 2 is 1-9:1, the mass ratio of NaOH is BZCY and the total mass of NaAlO 2 is 5-20%, and the solid oxide fuel cell with the electrolyte material obtained by mixing BZCY, naAlO 2 and NaOH is also provided. The invention improves the ion transport capacity of the electrolyte, reduces the lowest operable temperature of the battery device, and the created solid-liquid interface of the solid electrolyte under the in-situ condition is beneficial to keeping the proton activated state, so that the fuel cell has 320 ℃ operation capacity, and simultaneously improves the steady state existence of the solid-liquid interface in the electrolyte, thereby being beneficial to improving the performance and stability of the fuel cell at low temperature.

Inventors

• ZHU CHENGJUN
• ZHANG YINGBO
• ZHU DECAI
• YU JIANGYU
• NIU YAOHUI
• ZHANG QIAN

Assignees

• 内蒙古大学

Dates

Publication Date

20260512

Application Date

20260204

Claims (6)

1. 1. A three-phase composite solid electrolyte material is characterized by comprising BZCY, naAlO 2 and NaOH, wherein BZCY is BaZr 0.2 Ce 0.7 Y 0.1 O 3-δ , the mass ratio of BZCY to NaAlO 2 is 7:3, and the mass of NaOH is 10% of the total mass of BZCY and NaAlO 2 after being compounded.
2. 2. The method for preparing a three-phase composite solid electrolyte material according to claim 1, comprising the steps of: 1) BZCY, naAlO 2 and NaOH are weighed according to the formula ratio; 2) BZCY and NaAlO 2 are dissolved in a solvent, and the precursor composite material is obtained after ultrasonic, microwave, pre-activation and ball milling treatment; 3) And compounding the obtained precursor composite material with NaOH to obtain electrolyte powder.
3. 3. The preparation method of the three-phase composite solid electrolyte material according to claim 2, wherein in the step 2), the ultrasonic treatment time is 30-60 min, the solvent is ethanol, and/or the microwave treatment power is 300-500W, the microwave treatment time is 20-40 min, and/or the ball milling time is 3-5 h.
4. 4. The method for preparing a three-phase composite solid electrolyte material according to claim 2, wherein in the step 3), the obtained precursor composite material is dispersed in a solvent, a suspension a is obtained by ultrasonic treatment, naOH is dissolved in deionized water to obtain a solution b, and then the solution b is added dropwise to the suspension a, and after stirring, gradient heating, vacuum drying and full grinding, electrolyte powder is obtained.
5. 5. A solid oxide fuel cell comprising the three-phase composite solid electrolyte material of claim 1.
6. 6. The solid oxide fuel cell of claim 5, wherein the anode and/or cathode material of the solid oxide fuel cell is γ -Al 2 O 3 /NCAL.

Description

Three-phase composite solid electrolyte material and solid oxide fuel cell with same Technical Field The invention relates to the technical field of solid oxide fuel cells, in particular to a three-phase composite solid electrolyte material and synthesis preparation thereof, and a solid oxide fuel cell with the same. Background The development of the fuel cell starts in the middle of the 20 th century, is a green energy device which is efficient, low in pollution and wide in application, can directly convert chemical energy of clean fuel into electric energy through electrochemical reaction, is originally used for aerospace and military application, and gradually expands the application range to the fields of transportation, portable power sources, fixed power stations and the like along with the progress of technology. Among the many types of fuel cells, solid oxide fuel cells (Solid oxide fuel cell, SOFC) are of interest due to their high efficiency, low emissions, and ability to utilize multiple fuels. In recent years, SOFC technology has been significantly advanced, including breakthrough in material science and optimization of system design, so that performance and reliability thereof at high temperature are improved. However, conventional SOFCs operate at temperatures up to 800 to 1000 ℃ and still suffer from high temperature-induced material degradation, high cost, and high fuel requirements. Reducing the operating temperature of a Solid Oxide Fuel Cell (SOFC) can provide significant advantages in many ways, such as operating at lower temperatures to help reduce thermal energy losses, and by optimizing electrochemical reaction kinetics to increase energy conversion efficiency and enhance overall system performance. The low temperature reduces the energy demand for high temperature maintenance, reduces the energy consumption of the auxiliary heating system, effectively reduces the running cost and improves the economic feasibility of the system. The low-temperature system generates less heat, the thermal stress and overheat risk are obviously reduced, and the stability and the safety of the system operation are improved. At lower temperature, the aging mechanisms such as thermal expansion mismatch, interface reaction, microstructure degradation and the like of the key materials are relieved, the battery performance attenuation is obviously delayed, the service life is prolonged, and the maintenance frequency and the related cost are reduced. The low-temperature SOFC system is easier to realize compact design and quick start and stop, has stronger environmental adaptability, is more suitable for various application scenes such as portable power sources, mobile equipment, transportation and the like, and provides wider development space for large-scale popularization and commercialization application of fuel cell technology. At present, a novel low-temperature solid oxide fuel cell-semiconductor ion fuel cell (Semiconductor ionic fuel cell, SIFC) which takes NCAL as a symmetrical electrode and takes a semiconductor heterostructure composite material as electrolyte is paid attention to due to high performance at low temperature, the electrolyte is matched with different types of semiconductor materials, and through energy band alignment between two phase materials, a local field effect generated on an electrolyte heterogeneous interface due to electron charge difference distribution is realized, and the field effect acts on ion acceleration and electron suppression on the heterogeneous interface, so that the ion conductivity is improved, the open-circuit voltage of the cell is improved, and excellent cell performance in a temperature range of 450-550 ℃ is obtained. In this type of fuel cell, another key factor in achieving high performance at low temperature is the construction of a conductive network of molten hydroxide within the electrolyte, which enables the maintenance of rapid ionic conductivity at the heterojunction surface, thus enabling the cell to achieve high electrochemical output performance in low temperature environments. However, when the operating temperature of the cell is further reduced (< 400 ℃) it has been shown that the molten hydroxide conductive network within the SIFC electrolyte can transition from the molten state to the condensed state, and that disruption of the liquid phase rapid ion transport network can directly result in significant deterioration of the electrolyte interface ion transport capability, leading to irreparable deterioration of the OCV of the cell and serious problems of fuel cell device failure to operate. Therefore, how to regulate the melting point of the molten hydroxide in the electrolyte to make the melting point lower and exist in a molten state stably for a longer time, and determine the evolution process of the phase structure at the solid-liquid interface and the key role of the molten hydroxide network in improving the ionic conductivity are the ke