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Polymer vs Li-IonBatteries: The Key Differences You Can’t AffordtoIgnore

Lithium Battery Basics A polymer battery refers to a lithium-ion battery that uses polymer as the electrolyte. Specifically, it is further divided into two types: “semi-polymer” and “full-polymer”. The “semi-polymer” type means coating a layer of polymer (usually PVDF) on the separator, which makes the bonding force of the cell stronger and the battery can be made harder. Its electrolyte is still liquid electrolyte. The “full-polymer” type refers to using polymer to form a gel network inside the cell, and then injecting electrolyte to form the electrolyte. Although the “full-polymer” battery still needs to use liquid electrolyte, the amount is much less, which greatly improves the safety performance of the lithium-ion battery. As far as the author knows, currently only SONY is mass-producing “full-polymer” lithium-ion batteries.  From another perspective, a polymer battery refers to a lithium-ion battery that uses an aluminum-plastic packaging film as the outer packaging, also comm...
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Elaborate the Lithium-ion Battery Manufacturing Process 5 - Winding/Stacking

  Winding Process 1. Principle and Process Principle: The winding process involves the use of a fixed winding needle to wind and compress the pre-processed anode sheets, separator, and cathode sheets in sequence to form a cylindrical or elliptical shape. Process: The raw materials are stacked in the sequence of anode, separator, cathode, separator. Then, they are wound into cylindrical or elliptical shapes and placed into metal casings, either square or cylindrical. Specific steps include the unwinding of the anode and cathode sheets and separators, automatic alignment, automatic tension detection and control. The anode and cathode sheets are fed into the winding section by a clamp feeding mechanism, which, together with the separator , undergoes automatic winding according to specified process requirements. After the winding is completed, the machine automatically switches workstations, cuts the separator, attaches the end seal tape, and the finished bare cell is automatically dis...

The Influence of Polymerization Temperature on the Volume Expansion of Battery Cells Analysis  

Preface Formation is a critical step in the production process of lithium-ion batteries. The primary purpose of formation is to generate a solid electrolyte interphase (SEI) on the surface of the anode, which serves to isolate electrons while allowing ion conduction. The quality of the SEI formation directly affects the subsequent cycling performance of the battery. Therefore, controlling appropriate formation conditions (such as formation temperature, charging rate, applied pressure, etc.) is a crucial production step. The SEI formation process is accompanied by an increase in the volume of the battery. This increase is attributable to two main factors: the gaseous byproducts generated during the film formation reaction and the expansion of the anode structure as lithium ions are extracted from the cathode and intercalate into the anode.   In this study, in-situ volume monitoring instruments (GVM) are employed to conduct in-situ volume testing of NCM523/graphite cells (theoretic...

An Overview of the Four Steps in the Formation of Lithium Batteries

The formation process is an indispensable step in the manufacturing of lithium-ion batteries, as it directly affects the battery’s performance, safety, and lifespan. One of the key roles during the formation process is the formation of a stable solid electrolyte interphase (SEI) film on the surface of the anode. The SEI film protects the anode material from further erosion by the electrolyte, preventing the dissolution of the anode material in the electrolyte and thus extending the battery’s lifespan. At the same time, a stable SEI film can prevent the continuous decomposition of the electrolyte during subsequent charging and discharging cycles, reducing internal side reactions and thereby minimizing performance degradation. The formation process of lithium batteries is divided into four steps: open-circuit charging, closed-circuit charging, closed-circuit aging, and closed-circuit discharging. 1.Open-Circuit Charging (Pre-charging or Gas Venting) This step primarily involves charging ...

An Overview of the Four Steps in the Formation of Lithium Batteries

An Overview of the Four Steps in the Formation of Lithium Batteries The formation process is an indispensable step in the manufacturing of  lithiumion batteries , as it directly affects the battery’s performance, safety, and lifespan. One of the key roles during the formation process is the formation of a stable solid electrolyte interphase (SEI) film on the surface of the anode. The SEI film protects the  anode  material from further erosion by the electrolyte, preventing the dissolution of the anode material in the  electrolyte  and thus extending the battery’s l...