CN-122025653-A - Aluminum current collector based on aluminum silicate coating and preparation method and application thereof

Abstract

The invention discloses a preparation method of an aluminum current collector based on an aluminum silicate coating, which comprises the following steps: and (3) carrying out electrochemical deposition in silicate-containing electrolyte on the pretreated aluminum matrix to form an aluminum silicate coating, thereby obtaining the aluminum current collector. The invention also discloses an aluminum current collector based on the aluminum silicate coating, which comprises an aluminum matrix and the aluminum silicate coating covered on the surface of the aluminum matrix. The invention also discloses application of the aluminum current collector based on the aluminum silicate coating in assembling power devices and energy devices. The aluminum current collector based on the aluminum silicate coating, which is provided or prepared by the invention, has high hydrophilicity, low interface impedance and high-efficiency ion transmission capacity, and can obviously improve the cycling stability of devices when being applied to assembly power devices and energy devices.

Inventors

• BO ZHENG
• YANG HUACHAO
• Long Yuwei
• YAN JIANHUA

Assignees

• 浙江大学

Dates

Publication Date

20260512

Application Date

20260205

Claims (9)

1. 1. The preparation method of the aluminum current collector based on the aluminum silicate coating is characterized by comprising the steps of carrying out electrochemical deposition in electrolyte containing silicate on a pretreated aluminum substrate to form the aluminum silicate coating, and obtaining the aluminum current collector.
2. 2. The method for preparing an aluminum current collector based on an aluminum silicate coating according to claim 1, wherein electrochemical deposition is performed in an electrolyte containing silicate at a constant current density of 1.0-2.5 ma.cm –2 .
3. 3. The method for preparing aluminum current collector based on aluminum silicate coating according to claim 2, wherein the electrochemical deposition adopts a three-electrode system, and the electrolyte is selected from sodium silicate, lithium silicate, potassium silicate, ammonium silicate or aluminum potassium silicate.
4. 4. The method for preparing an aluminum current collector based on an aluminum silicate coating according to claim 1, wherein the pretreatment of the aluminum substrate comprises mechanical polishing, rinsing, chemical etching in an alkaline solution, neutralization in an acidic solution and rinsing in sequence.
5. 5. An aluminum current collector based on an aluminum silicate coating, characterized in that the aluminum current collector comprises an aluminum substrate and an aluminum silicate coating covering the surface of the aluminum substrate.
6. 6. The method of manufacturing an aluminum current collector based on an aluminum silicate coating according to claim 5, wherein the thickness of the aluminum silicate coating is 10-30 nm.
7. 7. Use of an aluminum current collector prepared by the preparation method of any one of claims 1 to 4 or based on an aluminum silicate coating of any one of claims 5 to 6 for assembling power type devices and energy type devices.
8. 8. The use according to claim 7, characterized in that the aluminum current collector based on aluminum silicate coating is used in supercapacitors and lithium ion batteries.
9. 9. The use according to claim 7, characterized in that the aluminum current collector based on aluminum silicate coating is used in aqueous supercapacitors, aqueous lithium ion batteries and aqueous soft-pack supercapacitors.

Description

Aluminum current collector based on aluminum silicate coating and preparation method and application thereof Technical Field The invention belongs to the technical field of water system electrochemical energy storage, and particularly relates to an aluminum current collector based on an aluminum silicate coating, and a preparation method and application thereof. Background The water system electrochemical energy storage system becomes a research hot spot for large-scale energy storage due to the advantages of safety and environmental protection, but the aluminum current collector has a serious corrosion problem in the water system electrolyte. Although titanium, nickel, stainless steel, and carbon-based current collectors exhibit better corrosion resistance than aluminum current collectors, aluminum current collectors are still in wide commercial use due to their excellent mechanical properties, electrical conductivity, light weight, and low cost. The etching process follows a two-step mechanism, first of all the electrode interface water molecules decompose to initiate hydrogen evolution/oxygen evolution reactions (HER/OER), producing corrosive H +/OH–, and then H +/OH– attacks the aluminum matrix to cause dissolution. Existing corrosion protection strategies focus on inhibiting the first step reaction. Bulk phase regulation is realized by reducing the free water content, for example, a high-concentration 'water in salt' electrolyte reduces the water activity by increasing coordinated water, or a deep eutectic solvent/organic cosolvent (such as dimethyl sulfoxide) is introduced to break a water molecule hydrogen bond network (for example, chinese patent publication No. CN112290086A discloses a lithium battery electrolyte which comprises electrolyte lithium salt, an organic solvent and an additive, wherein the organic solvent is phosphate organic solvent, carboxylate organic solvent and/or fluorocarboxylate organic solvent, and the concentration of the electrolyte lithium salt in the electrolyte is more than or equal to 1 mol/L). However, such methods do not completely eliminate free water and residual water molecules still cause corrosion. Interface regulation builds physical/chemical barrier contact. The biphase isolation film has the problems of mechanical brittleness, low ionic conductivity, interface transmission obstruction and the like. Physical adsorption type additives (such as zwitterions) rely on electric fields to maintain stability and tend to agglomerate to hinder ion migration. The chemical deposition oxide layer (such as TiO 2、Al2O3) is easy to hydrolyze and dissolve in long-term circulation (such as Chinese patent publication No. CN111463436A discloses a lithium ion battery current collector which comprises a three-layer composite structure, wherein the three-layer composite structure comprises a current collector substrate layer, a corrosion-resistant oxide layer sputtered on the current collector substrate layer and a conductive polymer layer grown on the surface of the corrosion-resistant oxide layer in situ). The conversion coating may compromise the integrity of the aluminum matrix. In order to prevent the corrosion problem caused by water, interface regulation is mostly based on the concept of 'hydrophobicity', and the interface contact of electrolyte and electrode is influenced, so that the performance of the device is influenced. The fundamental contradiction of the existing strategy is that high concentration electrolyte is needed for bulk control (deteriorating ion diffusion), thick and hydrophobic protective layer is needed for interface control (increasing interface impedance), both at the expense of device dynamics performance. If the regulation strength is reduced, the anti-corrosion effect is insufficient. The trade-off relationship, which is difficult to reconcile between corrosion inhibition and optimized interfacial dynamics, necessitates the development of alternative methods from a molecular level design perspective. Disclosure of Invention The invention aims to provide an aluminum current collector based on an aluminum silicate coating, a preparation method and application thereof, and the prepared aluminum current collector based on the aluminum silicate coating has high hydrophilicity, low interface impedance and high-efficiency ion transmission capacity, and can obviously improve the cycle stability of devices when applied to assembly power devices and energy devices. In order to achieve the above purpose, the invention adopts the following technical scheme: The preparation method of the aluminum current collector based on the aluminum silicate coating comprises the steps of carrying out electrochemical deposition in electrolyte containing silicate on a pretreated aluminum substrate to form the aluminum silicate coating, and obtaining the aluminum current collector. According to the method provided by the invention, the aluminum current collector based on the aluminu