1. What is NMP?

La NMP (nom complet : N-Méthylpyrrolidone), formule chimique C₅H₉NO, est un liquide clair et incolore et l'un des matériaux auxiliaires les plus utilisés dans la production de batteries au lithium.

Rôle dans la production d'électrodes : Lors de la fabrication des feuilles d'électrodes, le NMP sert de solvant pour mélanger les liants, les matériaux actifs (comme les matériaux cathodiques) et les agents conducteurs en une boue uniforme. Cela permet d'assurer une liaison uniforme entre tous les composants.

Solvent Superpower: It’s a high-boiling-point solvent that mixes well with almost all other solvents (alcohols, ketones, aromatics, etc.).

2. NMP Supply Chain Breakdown

Upstream:

Raw materials come from coal/petrochemical industries, mainly BDO (1,4-Butanediol). China’s coal industry has optimized BDO production, leading to rapid growth in capacity.

Midstream:

Production Methods:

Synthesis: BDO → γ-butyrolactone (GBL) → react with methylamine → refine into NMP.

Recycling: Used NMP from battery factories is purified (with ~10% loss) and blended with fresh NMP.

Current tech is reliable and mature.

3. Why NMP Matters in Lithium Batteries

Critical for Electrodes:

Dissolves PVDF (the go-to binder for cathodes) to create a stable slurry.

Ensures even coating of the slurry onto metal foils during battery assembly.

Small Cost, Big Impact: Auxiliary materials like NMP make up only 2-5% of battery costs but are essential for quality. Poor NMP = uneven coatings = worse battery performance.

4. NMP Production & Usage Stats (2022)

Global Capacity: 687,000 tons/year.

China’s Share: 532,000 tons/year (77% of global capacity).

Consumption:

Lithium Batteries: 1.428 million tons (94% of China’s total usage).

Other Uses:

Electronics (e.g., semiconductor cleaning): 4.0%

Polymers (e.g., specialty plastics): 1.6%

Insulating paints, pharma, petrochemicals: <1% each.

Key Takeaway: NMP is a behind-the-scenes hero in lithium batteries, ensuring electrodes are made right. China dominates its production, and recycling tech keeps it sustainable.