Lithium-ion batteries are batteries that use lithium metal or lithium alloy as the negative electrode material and a non-aqueous electrolyte solution. With the continuous development of the times, the application of lithium-ion batteries is becoming more and more widespread. Ultra-pure water equipment used for lithium-ion battery production is a set of dedicated water equipment used for electrolyte preparation. The water purification technology used by this equipment ensures that the water quality of the equipment meets the industry’s water needs.
The process flow of ultra-pure water equipment used in the lithium-ion battery industry is as follows:
Function Description of Ultra-Pure Water Equipment for Lithium-ion Battery Production
1. Online detection and display of ultra-pure water resistivity (MΩ.cm).
2. The product is small, integrated, modular, and has a quick-connect internal design, which is easy to install and maintain, occupies a small area, and has an aesthetically pleasing appearance.
3. Imported silent pumps are used, which run with no vibration, noise, or electromagnetic radiation, and have no impact on the working environment.
4. American high-capacity resin deep polishing purification technology improves the total exchange capacity of the ion exchange system and extends the life of consumables.
5. Digital LCD water quality display, fully automated water production, automatic power-off protection when there is no water or insufficient water pressure, simultaneous audio and visual alarms, and multiple protections.
6. Dynamic indication: power indication, system self-test indication, pump start indication, RO automatic flushing indication, lack of water protection indication, lack of water alarm indication, and pure water standby indication.
7. Fully automated unmanned design: the system automatically stops when there is a lack of water or water supply stops to protect the system. When the water pressure returns to normal, the system automatically resumes water production. When there is pure water in reserve, the system automatically stops. When a certain amount of pure water is used, the system automatically resumes water production.
8. Microcomputer intelligent control system, RO membrane anti-scaling program, and perfect automatic cleaning program.
9. Stylish appearance: using ABS material and precision processing, with exquisite craftsmanship, and smooth and beautiful lines.
Working Principle of Ultra-Pure Water Equipment in the Lithium-ion Battery Industry
1. The electro-deionization (EDI) system mainly uses a scientific water treatment technology to purify water by selectively passing ions through an exchange membrane based on the movement of the electrolyte ions in the water under the action of a DC electric field.
In the electro dialyzer, multiple sets of anion membranes, cation membranes, and partitions (A and B) are typically arranged alternately between a pair of electrodes, forming a concentrated chamber and a dilute chamber (i.e., cations can pass through the cation membrane, and anions can pass through the anion membrane).
2. In the dilute chamber, cations in the water migrate towards the negative electrode through the cation membrane and are intercepted by the anion membrane in the concentrated chamber. Anions in the water migrate towards the positive electrode through the anion membrane and are intercepted by the cation membrane in the concentrated chamber.
This gradually reduces the ion concentration in the dilute chamber, resulting in purified water, while the concentration of electrolyte ions in the concentrated chamber continues to increase due to the influx of anions and cations, resulting in concentrated water. In this way, the purpose of dilution, purification, concentration, or refinement is achieved. This is the process flow of customized ultra-pure water equipment for the lithium-ion battery industry.
Characteristics of Ultra-pure Water Equipment for Lithium-ion Battery Production
1. No need for acid-base regeneration: In a mixed bed, resins need to be regenerated with chemical agents, while EDI eliminates the handling of these harmful substances and the heavy work involved. It protects the environment.
2. Continuous and simple operation: In a mixed bed, the operation process becomes complex due to the variation of water quality after each regeneration, while the water production process of EDI is stable and continuous, and the water quality produced is constant, with no complex operation procedures. The operation is greatly simplified.
3. Reduced installation requirements: Compared with a mixed bed that processes an equivalent amount of water, the EDI system has a smaller volume. It adopts a modular design that can be flexibly constructed according to the site height. The modular design also facilitates maintenance during production.
4. In the design of ultra-pure water equipment for batteries, a two-stage RO+EDI+precision mixed bed desalination water treatment process with a high degree of automation is adopted to ensure that the water quality of the treated ultra-pure water meets the requirement of a resistivity of 18.2 MΩ.cm. The key equipment and materials use mainstream products, and the PLC+touch screen control is used. The entire system has a high degree of automation and stability, greatly saving labor and maintenance costs, and has high water utilization efficiency and economic rationality. Compared with other similar products, the equipment has a higher cost-effectiveness ratio and better equipment performance.