1. Wastewater Sources, Typical Pollutants & Water Characteristics
Wastewater generated during EV battery manufacturing primarily originates from key production processes including NCM (Nickel Cobalt Manganese) and Lithium Iron Phosphate (LFP) cathode material preparation, electrode coating, NMP solvent recovery, electrolyte filling, formation and grading, battery cell and equipment cleaning, as well as workshop floor washing. Wastewater characteristics vary significantly among production processes, with NCM battery manufacturing generally producing more complex and highly contaminated wastewater.
The wastewater mainly contains three categories of pollutants:
- Hazardous heavy metals – NCM production lines generate complexed nickel (Ni), cobalt (Co), and manganese (Mn), while LFP production mainly contains high concentrations of lithium (Li). These metal complexes are difficult to remove using conventional precipitation processes.
- Refractory organic compounds – Primarily including N-Methyl-2-pyrrolidone (NMP), PVDF binders, and carbonate-based electrolytes. The combined wastewater COD typically ranges from 5,000–8,000 mg/L, with extremely poor biodegradability (B/C ratio < 0.2).
- Inorganic pollutants – Including high concentrations of fluoride, phosphate, and sulfate. Total Dissolved Solids (TDS) in concentrated wastewater can exceed 28,000 mg/L, while pH fluctuates across a wide range. The wastewater is highly corrosive and subject to significant hydraulic and pollutant load fluctuations.
Wastewater treatment systems must comply with the stringent requirements of GB 30484-2013 – Discharge Standard of Pollutants for Battery Industry.
2. Common Customer Challenges
Environmental compliance requirements for EV battery manufacturers continue to become more stringent. Heavy metals such as nickel and cobalt, together with fluoride, are subject to strict regulatory limits, and even minor fluctuations in wastewater quality may trigger environmental compliance risks.
Traditional treatment technologies have limited capability for removing complexed heavy metals, requiring excessive chemical dosing while generating large volumes of hazardous sludge, resulting in high operating costs.
Refractory organic compounds such as NMP and electrolyte residues frequently cause membrane fouling, equipment blockage, and unplanned shutdowns, affecting continuous battery production.
Meanwhile, high-salinity wastewater has a low resource recovery rate, leading to the loss of valuable metals such as lithium, nickel, and cobalt. Conventional standardized treatment equipment is not designed to handle the highly saline, corrosive, and fluctuating wastewater conditions typical of lithium battery manufacturing, resulting in poor adaptability and frequent equipment failures.
In addition, conventional civil wastewater treatment facilities occupy large areas, offer limited automation, and cannot easily accommodate rapid production capacity expansion. Battery manufacturers increasingly require integrated, customized wastewater treatment solutions specifically designed for EV battery production.
3. Treatment Process & Core Equipment Configuration
To address the unique characteristics of EV battery wastewater, we employ an integrated treatment process consisting of:
Segregated Collection & Pretreatment → Decomplexation & Advanced Oxidation → Biological Treatment → Dual-Membrane Desalination → MVR Zero Liquid Discharge (ZLD)
High-strength process wastewater and equipment cleaning wastewater are collected separately before equalization and homogenization. The wastewater then enters a dedicated decomplexation reactor, where stable heavy metal complexes are effectively broken down.
Subsequently, coagulation and sedimentation, together with a high-efficiency fluoride removal system, eliminate suspended solids and the majority of inorganic contaminants.
An ozone advanced oxidation process (AOP) is applied to decompose refractory organic compounds such as NMP, significantly improving wastewater biodegradability.
The biological treatment stage utilizes an A/O + MBR process to effectively remove COD and ammonia nitrogen.
For advanced desalination, an anti-fouling Ultrafiltration (UF) system combined with Reverse Osmosis (RO) produces high-quality reclaimed water suitable for reuse in battery manufacturing processes.
The concentrated brine is further treated using DTRO membrane concentration followed by MVR evaporation and crystallization, achieving near Zero Liquid Discharge (ZLD).
Core equipment includes:
- Heavy metal decomplexation reactors
- High-efficiency fluoride removal systems
- Micro/nano advanced oxidation systems
- Anti-fouling membrane filtration systems
- MVR evaporators
- Automatic intelligent chemical dosing systems
- Online water quality monitoring systems
4. Solution Advantages
Our solution is specifically developed to address the most challenging aspects of EV battery wastewater treatment.
The system achieves a 99.9% removal efficiency for complexed heavy metals, while maintaining fluoride concentrations below 1 mg/L, consistently producing effluent that exceeds national discharge standards.
We offer fully customized equipment designs based on wastewater characteristics, treatment capacity, available installation space, and future production expansion plans. Customized anti-corrosion housings, wear-resistant structures, anti-clog flow channels, and modular equipment configurations ensure reliable performance under highly saline, corrosive, and variable operating conditions.
All core mechanical equipment, electrical control systems, and water treatment components are certified to CE, UL, and ISO standards, complying with both European Machinery and Electrical Safety Directives as well as North American safety requirements. This ensures excellent operational safety, reliability, and global project compliance.
The proprietary treatment process is specifically optimized for wastewater containing high concentrations of organic pollutants, salts, and heavy metals. Its superior resistance to hydraulic and pollutant load fluctuations significantly reduces membrane fouling and lowers maintenance frequency by more than 65%.
The system achieves over 90% water reuse, while simultaneously recovering valuable metals such as lithium, nickel, and cobalt, substantially reducing freshwater consumption, hazardous waste disposal costs, and raw material losses.
The modular integrated design reduces installation space requirements by approximately 40% compared with conventional treatment systems and allows flexible future capacity expansion.
Fully automated intelligent process control continuously optimizes chemical dosing and operating parameters, minimizing labor requirements while providing comprehensive compliance documentation to support environmental inspections and project acceptance.
5. Project References & Supporting Documentation
We have successfully delivered wastewater treatment systems for numerous leading EV battery manufacturers, covering both NCM and LFP battery production facilities.
A representative project is an 8 GWh/year EV Battery Manufacturing Zero Liquid Discharge (ZLD) Project, with a wastewater treatment capacity of 800 m³/day.
The system consistently recycles treated water back into the production process, saving approximately 220,000 m³ of freshwater annually while reducing hazardous waste generation by more than 50%. The project successfully passed all environmental acceptance inspections.
Supporting documentation includes:
- Proprietary wastewater treatment patents
- CE, UL, and ISO certifications
- Third-party water quality testing reports
- Environmental acceptance approvals
- Reference contracts for comparable projects
- Comprehensive operation and maintenance warranty documentation
6. Service Scope & Cooperation Process
We provide comprehensive EPC turnkey wastewater treatment solutions, including site investigation, wastewater characterization, laboratory and pilot-scale testing, customized process engineering, non-standard equipment manufacturing, civil construction support, installation, commissioning, environmental compliance consulting, system operation and maintenance, process upgrades, and long-term consumables supply.
Customized solutions for heavy metal recovery and wastewater resource recovery are also available based on customer requirements.
Standard Cooperation Process
- Site Survey & Water Sampling – Conduct on-site investigation, collect wastewater samples, and issue a professional water quality analysis report.
- Customized Process Design – Develop a tailored treatment solution, technical proposal, and commercial quotation based on plant operating conditions.
- Equipment Manufacturing & Construction – Begin customized equipment fabrication and civil construction after contract confirmation.
- Installation & Commissioning – Complete equipment installation, integrated system commissioning, and trial operation until stable compliance is achieved.
- Project Acceptance & Training – Assist with environmental compliance acceptance and provide comprehensive operator training.
- Long-term Technical Support – Deliver preventive maintenance, routine inspections, system optimization, equipment upgrades, and lifetime after-sales technical support.
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