Figure 1 introduces the current state-of-the-art battery manufacturing process, which includes three major parts: electrode preparation, cell assembly, and battery electrochemistry activation. First, the active material (AM), conductive additive, and binder are mixed to form a uniform slurry with the solvent.
The production process of a lithium-ion battery cell consists of three critical stages: electrode manufacturing, cell assembly, and cell finishing. The first stage is electrode manufacturing, which involves mixing, coating, calendering, slitting, and electrode making processes.
Besides the cell manufacturing, “macro”-level manufacturing from cell to battery system could affect the final energy density and the total cost, especially for the EV battery system. The energy density of the EV battery system increased from less than 100 to ∼200 Wh/kg during the past decade (Löbberding et al., 2020).
The first stage is electrode manufacturing, which involves mixing, coating, calendering, slitting, and electrode making processes. The second stage is cell assembly, where the separator is inserted, and the battery structure is connected to terminals or cell tabs.
Using smart manufacturing approaches, such as digital twins to create a positive feedback loop between online/offline real manufacturing data and simulated data via artificial intelligence, can effectively optimize the manufacturing process and improve the yield rate of battery manufacturing.
In the next section, we will delve deeper into the battery cell assembly processes. Battery cell assembly involves combining raw materials, creating anode and cathode sheets, joining them with a separator layer, and then placing them into a containment case and filling with electrolyte.