BACKGROUND

1. Definition of PFAS: (per -&polyfluoroalkyl substances) series of non natural compounds, in which some of the H in the C-H bonds on the molecular carbon chain skeleton may be replaced by F to form fluorinated hydrophobic chains, including PVDF, PTFE, etc
2. PFAS hazards: Potential endocrine disruptors associated with various adverse outcomes, including reproductive and developmental toxicity, may affect the functional persistence of reproductive hormones and are almost not biodegraded
3. PFAS Act: In 2021, the United States required that PFAS not be detected in packaging materials.
Article 68 of Annex 17 of the EU REACH Regulation restricts C9-C14 PFCA
3M plans to discontinue the use of PFAS in its product portfolio by the end of 2025

Fluorine free adhesive HJ815

The molecular structure of fluorine free adhesive HJ815 is an acrylic copolymer, which is non-toxic and biodegradable, avoiding the PFAS Act. And it has good adhesion and chemical corrosion resistance, which can bond the electrode material into a film under high temperature and high pressure conditions, ensure good contact between the electrode and electrolyte, and improve the performance and life of the battery. The R&D team of Jintianchi has developed a binder suitable for lithium battery negative electrodes by modifying fluorine free adhesive products. It can replace traditional SBR binders, with better adhesion, lower dosage, and lower impedance.

HJ815 product advantages

Although the amount of negative electrode binder is extremely small (only used for homogenization and coating of graphite negative electrode materials), it is an indispensable component. During the electrode coating process, the evaporation of solvents due to drying speed affects the migration of negative electrode binder, resulting in different distribution states of negative electrode binder. The resulting slurry and electrode microstructure have significant differences, which directly affect the performance of the battery. Improper use of negative electrode binder can cause differences in the microstructure of the electrode, affecting the bonding performance of graphite negative electrodes, and making it easy to stick to the roller during rolling; The bonding performance between graphite negative electrode and copper foil is affected, and the electrode sheet is prone to polarization during battery charging and discharging, causing negative electrode material to fall off and reducing the service life of the battery. The negative electrode fluorine free binder developed by our company can improve the migration of binders caused by the evaporation of drying solvents, thereby improving the distribution of binders, reducing the probability of roller adhesion, reducing polarization during battery charging and discharging processes, and improving the electrical performance and service life of batteries.

Keywords: SBR CMC flexible agent cracking agent coated carbon aluminum foil adhesive graphene