<2025> Development Status and Outlook of Binder Technology for Secondary Batteries (~2035)

The characteristics of LIBs are largely determined by the electrodes, and optimizing the electrode structure is the top priority in order to achieve excellent battery performance. While the active materials of the cathode and anode are being studied and reviewed with much interest not only in currently commercialized LIBs but also in the research field, the inactive binder that does not participate in the electrode reaction maintains the integrity of the electrode with a low weight ratio (less than or equal to 5 wt%) and supports the electrochemical process, and occupies an important position in terms of implementing the performance of the electrode along with the active material and the conductive agent, but it is receiving less attention compared to its importance.

The binder occupies a very small portion of the electrode but plays a crucial role in determining the overall performance of the electrode. It helps active materials and conductive agents in both the cathode and anode adhere firmly to the current collector while enhancing durability. A binder must be (1) electrochemically stable in the electrolyte, (2) possess flexibility and insolubility, and (3) specifically for cathode binders, provide corrosion resistance against oxidation.

Therefore, a functional binder with high bonding strength and elasticity is required to effectively connect the active material and conductive agent to the current collector, accommodate volume expansion, and ensure a stable electrode structure during charge and discharge cycles. Recently, with deeper insights into binder screening and design, research has been shifting its focus from merely serving as a structural support for mechanical stabilization to developing multifunctional binders that also provide electrochemical advantages.

Recently, with the increasing adoption of silicon anode materials, research has shown that binders significantly influence the lithiation reaction, contributing to improved electrode capacity and cycle stability. This has led to active advancements in next-generation binder development. Traditionally, fluoropolymer-based PVDF (Polyvinylidene Fluoride) has been primarily used as a binder for cathodes, while SBR (Styrene-Butadiene Rubber) and CMC (Carboxymethyl Cellulose) have been used for anodes. However, due to the significant volume expansion of silicon anodes, these conventional binders are unsuitable for use with silicon-based materials.

Recently, PTFE (PolyTetraFluoroEthylene) binders have been gaining attention for cathodes, while water-based binders such as PAA (PolyAcrylic Acid) and PI (PolyImide) are increasingly used for anodes. These water-based binders are particularly suitable for silicon anodes, which utilize water-based solvents as electrolytes. Compared to conventional binders, PAA and PI offer higher tensile strength and stronger adhesion, making them more resistant to the volume expansion of silicon anodes. Additionally, these binders encapsulate the active material, helping to form a stable SEI (Solid Electrolyte Interphase) layer, which enhances electrode stability and cycle performance.

The next-generation cathode binder, PTFE (PolyTetraFluoroEthylene), is a binder for dry electrode processes. As a highly hydrophobic material with excellent chemical and thermal resistance, it is expected to gain attention for use in dry electrode processes and solid-state batteries.

PVDF binders are produced by Kureha (Japan), Solvay (Belgium), and Arkema (France), while SBR binders are manufactured by Zeon (Japan), making them high-cost materials with a high reliance on foreign suppliers.

For cathode binders, Chemtros (South Korea) has successfully localized production, while for anode binders, Hansol Chemical (South Korea) has also achieved domestic production and is supplying to Samsung SDI and SK On. Additionally, LG Chem and Kumho Petrochemical are entering the anode binder supply market.

According to SNE Research's global demand forecast for lithium-ion battery binders as of November 2024, the market is expected to grow from 181.2 kton in 2025 to 311.4 kton in 2030. In terms of value, it is projected to increase from KRW 4.4 trillion in 2025 to KRW 6.11 trillion in 2030.

The 2024 edition of the report has been enhanced with a particular focus on solid-state batteries and sodium-ion batteries, which have recently become hot topics. It includes thermal and dispersion properties of binders for these next-generation batteries and provides additional insights into the operational mechanisms and failure mechanisms of binders to improve understanding. Additionally, the report presents a chronological compilation of research on binder design, synthesis, and application in lithium-ion battery electrodes, covering all relevant literature published to date. For those seeking deeper technical details, references to the original papers have been included, allowing for further exploration of the subject.

Based on our lithium-ion battery market outlook, we have projected the demand and market trends for binders. In the appendix, we have included market size estimates and forecasts from external research institutions to help readers gain a comprehensive understanding of the overall market scale. For key binders such as PVDF, SBR, and CMC, the report includes detailed market data from 2021, 2022, and 2023, along with forecasts for 2024, providing a clear view of demand trends over time.

Finally, by compiling the most recent status and key products of binder manufacturers in 2024, this report aims to provide comprehensive insights for researchers and industry professionals. It is expected to contribute significantly to improving battery performance, including energy density, fast-charging capability, and long-term cycle life.

Strong Points of This Report :

• 1. Comprehensive overview and detailed technical content on binders
• 2. Key design and synthesis considerations derived from binder development case studies
• 3. Analysis of binder development trends and case studies for next-generation batteries, including Li-S batteries, solid-state batteries, and sodium-ion batteries (SIBs), in addition to LIBs
• 4. Binder market outlook based on SNE Research's battery forecasts, along with data on the binder market for LFP batteries
• 5. Detailed information on the latest developments and product status of major binder manufacturers

[PVDF Binder Manufacturers' Shipment Volume and Market Share (M/S)]

[SBR Binder Manufacturers' Shipment Volume and Market Share (M/S)]

Global LIB Binder(Cathode + Anode) Demand Forecast (kTon)

[Tesla 4680 Battery Binder Cost Analysis]

• Cathode: NCM811, Anode: Si-based
• PVDF cathode binder requirement and cost for 1 GWh battery: around 38 tons
• PAA anode binder requirement and cost for 1 GWh battery: around 24 tons