CN-115954556-B - Water system liquid electrode battery based on self-adsorption and self-layering effect

CN115954556BCN 115954556 BCN115954556 BCN 115954556BCN-115954556-B

Abstract

The application discloses a water-based liquid electrode battery based on self-adsorption and self-layering effects, which is characterized in that a water-soluble salt containing hydrophobic imidazoles and a water-soluble salt containing bistrifluoromethyl sulfonyl imide ions are respectively dissolved in deionized water solution, the two water solutions are mixed and kept stand, an adsorptive carbon material, conductive carbon black and polyvinylidene fluoride are mixed and dispersed in an organic solvent, the mixture is stirred into a syrup-like viscous mixture to be smeared on a current collector, the mixture is dried in a vacuum drying oven, a commercial zinc foil is used as an anode of the battery, a Whatman filter membrane infiltrated by 3 moles per liter of zinc triflate is used as a positive and negative separator, the current collector infiltrated by the prepared ionic liquid is used as a cathode to construct the water-based liquid electrode battery based on self-adsorption and self-layering effects, and the self-assembled 1-ethyl-3-methylimidazolbis bis (trifluoromethyl sulfonyl) imide liquid electrode simultaneously realizes liquid self-layering, fixed redox active substances and penetrating ion conduction.

Inventors

JIN ZHONG
ZHANG KAIQIANG
TIE ZUOXIU
LI JIARUI
WANG FAN

Assignees

南京大學天长新材料与能源技术研发中心
南京大学
南京铁鸣能源科技有限公司
苏州铁睿新能源科技有限公司
滁州极鑫新能源科技有限公司

Dates

Publication Date: 20260508
Application Date: 20221229

Claims (9)

1. An aqueous liquid electrode cell based on self-adsorption and self-layering effects, characterized in that the aqueous liquid electrode cell based on self-adsorption and self-layering effects comprises: Commercial zinc foil as anode of the cell; a Whatman filter membrane infiltrated by 3 moles per liter of zinc triflate electrolyte is used as a positive and negative electrode interlayer; the self-assembled ionic liquid electrode infiltrates a current collector to serve as a cathode of the battery; the preparation method of the cathode comprises the following steps: Firstly, preparing a self-assembled ionic liquid electrode, namely taking a water-soluble salt containing hydrophobic imidazoles and a water-soluble salt containing bistrifluoromethyl sulfonyl imide ions in a molar ratio of 1:1, respectively dissolving the water-soluble salt and the water-soluble salt in deionized water to prepare 10-20 mol/L aqueous solution, stirring the aqueous solution until the aqueous solution is completely dissolved, directly pouring the aqueous solution into the same container without distinction, mixing the aqueous solution and standing the container for 8-24 hours, performing an ionic self-assembly process, and finally forming an upper-lower layered state, wherein the components of the upper layer and the lower layer are respectively ionic liquid and aqueous solution, and the upper layer and the lower layer of the two liquid substances are determined according to the density; Secondly, assembling a current collector, namely weighing and mixing an adsorptive carbon material, conductive carbon black and polyvinylidene fluoride according to the weight ratio of 4-7:2-5:1, dispersing the mixture in an organic solvent, and stirring the mixture into a syrup-shaped viscous mixture, smearing the prepared viscous mixture on the current collector, wherein the smearing thickness is 50-100 micrometers, placing the smeared current collector in a vacuum drying oven, and adding vacuum drying at 100-150 ℃ for 8-24 hours; Step three, preparing a cathode, namely infiltrating the self-assembled ionic liquid electrode prepared in the step one into a current collector dried in the step two, wherein the infiltration amount is 20 microlitres per square centimeter; the water-soluble salt containing hydrophobic imidazole is iodized 1-ethyl-3-methylimidazole, brominated 1-ethyl-3-methylimidazole or chlorinated 1-ethyl-3-methylimidazole.
2. The aqueous liquid electrode cell based on self-adsorption and self-stratification effect according to claim 1, wherein the water-soluble salt containing bis (trifluoromethylsulfonyl) imide is bis (lithium), bis (sodium), bis (potassium) or bis (zinc) trifluoromethylsulfonyl imide.
3. The aqueous liquid electrode cell based on self-adsorption and self-layering effects according to claim 1, wherein the organic solvent is methyl pyrrolidone, and the total powder weight of the adsorbent carbon material, the conductive carbon black and the polyvinylidene fluoride is calculated, and 4 ml of organic solvent is used for dispersing each gram of total powder weight.
4. The aqueous liquid electrode cell based on self-adsorption and self-layering effects of claim 1 wherein the adsorbent carbon material is activated carbon powder, single-walled carbon nanotubes, multi-walled carbon nanotubes or reduced graphene with or without the addition of unlimited amounts of zinc iodide or zinc bromide.
5. The aqueous liquid electrode cell based on self-adsorption and self-layering effects according to claim 1, wherein the current collector is a carbon material including, but not limited to, carbon cloth, conductive carbon paper, carbon felt.
6. The aqueous liquid electrode cell based on self-adsorption and self-stratification effect according to claim 1, wherein the aqueous liquid electrode cell based on self-adsorption and self-stratification effect is a zinc-iodine aqueous liquid electrode cell or a zinc-bromine aqueous liquid electrode cell.
7. The aqueous liquid electrode cell based on self-adsorption and self-layering effects of claim 6, wherein a current collector infiltrated by 1-ethyl-3-methylimidazole-bistrifluoromethylsulfonylimide ionic liquid is used as a cathode in the zinc-iodine aqueous liquid electrode cell, and a cation source in the cathode is 1-ethyl-3-methylimidazole iodide.
8. The aqueous liquid electrode cell based on self-adsorption and self-layering effects according to claim 6, wherein the electrolyte in the zinc-bromine aqueous liquid electrode cell is 3 moles per liter of zinc triflate and 20 moles per liter of lithium bis (trifluoromethylsulfonyl) imide, the cathode is a current collector infiltrated by a brominated 1-ethyl-3-methylimidazole-bis (trifluoromethylsulfonyl) imide ionic liquid, and the cation source in the cathode of the ionic liquid is brominated 1-ethyl-3-methylimidazole.
9. The aqueous liquid electrode cell based on self-adsorption and self-stratification effect according to claim 1, wherein 20 moles per liter of lithium bis (trifluoromethylsulfonyl) imide are added or not added to 3 moles per liter of zinc trifluoromethylsulfonate electrolyte.

Description

Water system liquid electrode battery based on self-adsorption and self-layering effect Technical Field The application belongs to the field of liquid batteries, and particularly relates to a water-based liquid electrode battery based on self-adsorption and self-layering effects. Background With the gradual exhaustion of fossil energy and the increasing increase of environmental problems caused by the massive use of fossil energy, scientists, engineers and the like of governments around the world are increasing in the effort to clean sustainable new energy sources, such as solar energy, nuclear energy and wind energy, and convert the new energy sources into electric energy for network power supply, so that the modern convenient life of people is ensured, and meanwhile, the dependence on fossil energy sources is gradually reduced and eliminated. In order to better store clean and convenient electric energy in various fields of life to ensure normal use of various functional devices, development of high-performance energy storage battery technology becomes an inexorable key link. At present, research on battery technology is mainly aimed at developing an ideal secondary battery with large capacity, long service life, quick charge, low cost, no pollution and safe use. These battery attributes, which need to be met simultaneously, work together to develop a high performance battery like the barrel principle, requiring as much practical requirements to be met as possible simultaneously. The energy storage principle of electrochemical cells relies primarily on the construction of a chemical potential difference by selecting an appropriate electrode material that affects the output voltage of the cell as a whole by storing (yielding) charged ions. Since the discovery of the earliest intercalated electrode materials, almost no exception has been made from solid materials to the design and construction of various composite electrode materials. However, the charge-discharge principle of the electrode material is just dependent on the phagocytosis (or release) of charged ions by the electrode material, and the process inevitably impacts the original microscopic atomic distribution structure of the electrode material, and as the phagocytosis and release processes are repeatedly performed, the microscopic structure of the electrode material collapses and collapses over time, and the charge-discharge capability of the battery is macroscopically lost. If the electrode material is required to maintain the original microstructure as long as possible, and further the ultra-long service life of the battery is realized, no or very weak impact on the microstructure of the electrode material in the charge and discharge processes is critical. From the above, it is clear that there is a serious paradox between the conventional battery charge and discharge and the long life battery that is desired to be realized. This suggests that further development of electrode materials requires a renewed thinking, and finding a charge-discharge mechanism that does not change the microstructure of the electrode materials during charge-discharge would theoretically fundamentally meet the needs of long-life batteries. From the above analysis, the liquid electrode, because it has no fixed microscopic atomic structure, this property meets exactly the requirements of a zero lattice stress electrode material. The three types of liquid electrodes developed at present are mainly divided into liquid metal electrodes, molten salt electrodes and liquid organic electrodes. The concept of liquid metal electrodes was first proposed by the university of ma, professor donaldr.sadoway in 2014 and reported a battery based on high temperature liquid metal electrodes. Batteries based on liquid metal electrodes have experienced slow development over the years thereafter. Similar to lava electrodes, liquid metal electrode cells generally require higher operating temperatures to maintain the metal electrodes In a liquid state (except for liquid metal electrodes such as Na/K and Ga/In). Both liquid metal batteries and molten salt electrode batteries generally require a ceramic solid state electrolyte to effect cathode-anode separation and carrier transport. Overall, batteries based on the two types of liquid electrodes described above define demanding operating conditions, high manufacturing costs on a large scale, and serious safety hazards. In contrast, flow batteries are typically liquid electrode batteries that operate at room temperature. The development of flow batteries has been over twenty years old, but their normal charge and discharge relies on a high cost ion conducting membrane intermediate the positive and negative fluids to prevent the occurrence of active electrolyte miscibility and cross-contamination, but the effectiveness of the high ion conducting membrane is limited. In addition, although redox active molecules (ions) in the liquid electrode have