Water-based cathode binders
Replacing NMP with water means managing particle surface reactions in water, corrosion risk to aluminium foil in alkaline slurry, and residual moisture after drying. LFP is the realistic entry point.
CASU · Advanced materials innovation
CASU is an advanced-materials innovation company focused on water-based cathode and anode binder systems for power and energy-storage batteries.
We start with material interfaces and formulation design, and carry the work through process fit and application evaluation.
- 2017Founded in Shanghai
- by DBC Group and the Chinese Academy of Sciences
- 4business areas
- chemicals, adhesives, battery and bio-based materials
- Cathode + anodewater-based binders
- for power and energy-storage batteries
- 5+ yrsworking with BASF
- on water-based anode binders
A few per cent of the formulation.The whole life of the electrode.
Whether a slurry stays stable, a coating stays even, an electrode holds on and a cell lasts — the binder system is part of every step.
Focus · Battery materials
Cathodes and anodes, treated separately.
Binders are a small fraction of an electrode, yet they decide slurry stability, coating quality, adhesion and electrode integrity over cycling. CASU selects and evaluates water-based binder systems electrode by electrode.
Water-based anode binders
Graphite anodes depend on slurry stability, copper adhesion and integrity after calendering. Silicon-containing anodes must also hold together through volume change. Different routes need different binders and tests.
By battery type
Four battery types, four sets of demands.
- 01
LFP energy storage
Long life, consistency, cost
Integrity of high-loading coatings and long-term wet adhesion
- 02
Traction batteries
Fast charge, low temperature, energy density
Adhesion, springback and ion pathways at high density
- 03
Si-C fast charge
Energy density with fast charge
Volume change, SEI stability and elastic blends
- 04
Sodium-ion
Low temperature, cost, safety
Aluminium adhesion, hard-carbon slurries, moisture-safe cathodes
Start from the problem
Which electrode problem are you solving?
Settling, gelation or viscosity drift
Start with addition sequence, CMC dissolution and shear history.
Low peel or base delamination
Binder migration during drying is often mistaken for low dosage.
Swelling in silicon anodes
Read elastic fraction, PAA neutralisation and network recovery together.
Moving a cathode to water
Follow the chain of pH drift, aluminium interface and residual moisture.
Businesses
Four areas. One way of working.
All four areas follow the same path: from material interfaces and formulation design to process fit and application evaluation.
01 · Focus
Battery materials
Water-based cathode and anode binder systems for power and energy-storage batteries.
02
High-end chemicals
Key raw materials and functional additives for material development and manufacturing.
04
High-performance bio-based materials
Bio-based polymers, engineered for battery and industrial use.
Approach
Material potential becomes value in the process.
A material that performs in the lab has to perform on the coating line. Every project moves along the same chain, with variables, methods and pass criteria at each step.
- 01
Material interfaces
How the binder wets, contacts and bonds with particles, conductive additives, current collectors or substrates.
- 02
Formulation design
How components, ratios, solids content and pH determine dispersion and storage stability.
- 03
Process fit
Whether the formulation stays controllable through mixing, coating, drying, calendering or film formation.
- 04
Application evaluation
Setting controls and criteria to decide whether a solution moves to the next stage.
Co-innovation
Co-innovation is how we work.
CASU was founded in Shanghai in 2017 by DBC Group and the Chinese Academy of Sciences. We bring international material systems, research expertise and the real needs of Chinese battery manufacturing to the same problem.
- 01
International material partner
CASU has worked with BASF on water-based anode binders for more than five years.
- 02
Research collaboration
Joint research and technical assessment on questions of applied chemistry, materials science and engineering.
- 03
DBC Group ecosystem
As an advanced-materials company within the DBC Group ecosystem, CASU works alongside the group’s materials and application businesses.
Can water-based binders be used for cathodes?
Yes, but it is harder than for anodes. Cathode particles leach lithium in water, raising slurry pH and risking aluminium-collector corrosion, and residual moisture must be tightly controlled. LFP is less water-sensitive and is the more practical aqueous route; nickel-rich cathodes are still mainly processed with PVDF in NMP.
Why do SBR and CMC usually appear together?
They do different jobs: SBR latex provides elastic bonding and copper adhesion; CMC thickens and stabilises the slurry and contributes to bonding. SBR alone cannot keep graphite slurry stable, and CMC alone gives brittle electrodes.
Do silicon anodes always need PAA?
No. PAA-type binders interact strongly with silicon and are common in Si-containing anodes, but they are stiff, and the degree of neutralisation affects pH, viscosity and ICE. The choice and any blend depend on silicon level, particle surface and process, and need controlled comparison.
Insights
What’s changing in batteries and materials.
Perspectives and industry tracking, each with its original sources.
Three hurdles for aqueous cathodes: pH, aluminium foil and residual water
Moving a cathode from NMP to water is not mainly a binder problem — it is a chain of reactions from particle to current collector. LFP is the realistic place to start.
Silicon-anode binders: from fixing particles to a recoverable network
Silicon’s volume change turns the binder from a supporting role into a key variable. The SBR + CMC system proven on graphite needs strong-interaction components, cross-linking and elastic design to hold the electrode together through cycling.
Sodium-ion anodes: when the current collector changes from copper to aluminium
Sodium does not alloy with aluminium, so sodium-ion anodes can use aluminium foil. The change brings cost and weight benefits — and gives the binder a new substrate and a new anode material, hard carbon.
Bring us a specific problem.
Tell us the application, the material system and the process conditions. We’ll take it from there.
- casu@cas.cc