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The commercialization of all-solid-state battery production is a complex system engineering process, with its core mainly consisting of three key components: material system development, cell structure design, and cell production control. To produce a high-performance commercial all-solid-state battery, it is essential to master these three core aspects. Once the process for manufacturing commercial all-solid-state batteries is mastered, assembling and producing coin-type half-cells, coin-type full-cells, and simple structure flexible batteries (with a single positive/negative electrode stacked structure) becomes relatively easy.

1.  Key Factors Influencing Formation: Mechanism Generation Process of SEI Membrane: l  Electrons are transferred from the current collector, through the conductive agent, to point A inside the graphite particles where the SEI membrane is to be formed. l  Solvated lithium ions, wrapped in the solvent, diffuse from the cathode to point B on the surface of the SEI membrane that is currently being formed. l  The electrons at point A diffuse to point B through the electron tunneling effect. l  The electrons that jump to point B react with lithium salt, solvated lithium ions, film-forming agents, etc., to continue generating the SEI membrane on the surface of the existing SEI membrane. This process results in the continuous increase of the SEI membrane thickness on the surface of the graphite particles, ultimately leading to the formation of a complete SEI membrane.

1.  Basic Concepts of Formation 1.1.  What is Formation? l  Formation refers to the process of activating the cathode and anode materials inside a battery after it has been fully rested following electrolyte injection. This activation is achieved through a specific charging and discharging cycle, which also leads to the formation of a SEI (Solid Electrolyte Interphase) film on the surface of the active materials. The SEI film helps to improve the overall performance of the battery in terms of charging and discharging, self-discharge, and storage capabilities.

  1. Coating Basics Purpose: To uniformly coat a fluid slurry onto the surface of a metal foil, dry it, and produce a battery electrode Principle: The coating roller rotates to carry the slurry, and the amount of slurry transferred is adjusted by adjusting the gap between the doctor blade and the roller. The relative rotation of the back roller and the coating roller is used to transfer the slurry onto the substrate. Subsequently, the solvent in the slurry is evaporated through drying and heating, causing the solid matter to adhere to the substrate.

  1. Electrode Shedding  Negative electrodes are prone to powder shedding  Main reason： 1. Formula issues,insufficient bonding strength leading to material loss 2.Excessive baking temperature,rapid solvent evaporation resulting in SBR bleeding.Insufficient adhesive between the material and the current collector leading to material loss

1. Coating Basics Purpose ： To uniformly coat a fluid slurry onto the surface of a metal foil, dry it, and produce a battery electrode Principle: The coating roller rotates to carry the slurry, and the amount of slurry transferred           is adjusted by adjusting the gap between the blade and the roller. The relative rotation of           the back roller and the coating roller is used to transfer the slurry onto the substrate.           Subsequently, the solvent in the slurry is evaporated through drying and heating, causing           the solid matter to adhere to the substrate.  

  1. The function of adhesives Cathode and anode slurries ：  Provide viscosity to ensure that particles in the slurry do not easily settle and maintain  s slurry stability  Provide viscosity for good fluidity  Provide viscosity to facilitate effective dispersion of materials

  1. Baking 1.1. The main purpose of baking is to remove moisture from the bare cell  H2O can cause the decomposition of LiPF6, leading to an increase in HF levels:  H2O can react with organic solvents in the electrolyte to produce alcohol and CO2, for example:  During the formation process, H2O can decompose, producing H2, consuming lithium ions, reducing the initial efficiency and capacity of the battery, and damaging the battery interface.

1. Rolling Principle Roll pressing is a process that utilizes a roll press machine (as shown in Figure 1,the roll press machine used in the industry consists of three core components: a pair of rollers, an unwinding device, and a rewinding device) to compress the thickness of the electrode (as shown in Figure 1). This compression increases the compaction density of the electrode coating, reduces the thickness of the electrode, and ultimately enhances the energy density of the battery.     2. Rolling Equipmen t Loading Sequence: Loading Device - Correction Device - Edge Trimming Device - Tension Device - Preheater - Rolling Mills - Tension Device - Correction Device - Winding Device   3. Rolling Effect 1） Improving Electronic Conductivity ：  When the compaction density of a porous electrode is low, there is poor contact between the particles, resulting in a necessarily high contact resistance. As the compaction density increases, the contact between the particles becomes ...