Polyvinylidene fluoride (PVDF) positive electrode binder

Bonding function:

Firmly bond the positive electrode active materials (such as lithium cobalt oxide, ternary materials, lithium iron phosphate), conductive agents (such as carbon black, graphene), and current collectors (aluminum foil) to form a uniform electrode film.

Ensure efficient electron conduction between the electrode materials and the conductive agents, reducing electrode impedance and battery polarization, and improving charging and discharging efficiency.

Chemical and electrochemical stability:

Resistant to electrolyte erosion: During battery charging and discharging, PVDF does not participate in the electrolyte reaction, avoiding the formation of by-products and protecting the electrode structure.

Wide electrochemical window: Decomposition voltage > 4.5V, suitable for high-voltage positive electrode materials (such as high-nickel ternary), meeting the requirements of high-voltage battery systems.

Mechanical performance support:

Withstand electrode volume changes: During charging and discharging of the positive electrode materials, there is expansion/contraction. The flexibility and impact resistance of PVDF can alleviate stress and prevent electrode cracking or detachment.

Maintain electrode structure integrity: By maintaining high adhesion, the electrode film and the current collector can maintain their adhesion, prolonging the battery cycle life.

Optimize film formation and ion transmission:

Uniform coating: The PVDF gel can form a dense coating, reducing the porosity of the electrode, and optimizing the ion transmission path.

Reduce polarization: The uniform electrode structure reduces local current density differences, reduces battery polarization, and improves power output capacity.