Further offers for the topic Battery technology

Poster-No.

P1-071_Philipp

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Vinylene carbonate (VC) is often added to liquid electrolytes as an additive to facilitate the formation of a stable solid electrolyte interphase (SEI) during initial charging. The SEI prevents undesirable side reactions on the anode side and ensures high cycle stability. However, a disadvantage of VC is its instability at high voltages, such as those seen with NMC and nickel-doped LMO, which can lead to unwanted side reactions at the cathode when high-voltage cathode active materials are used. To enable the use of VC with these materials and to avoid its negative effects, integrating VC into the anode without adding it to the electrolyte is of interest. This approach allows the beneficial properties associated with SEI formation to be utilized while simultaneously avoiding undesirable reactions at the cathode. This study investigates and evaluates the coating of graphite with PVC using a fluidized bed reactor to form an artificial SEI based on VC. The PVC-coated graphite particles were then processed into anodes, and full cells were assembled, Various characterization methods were used to confirm the successful the coating of the graphite particles with PVC. The influence of the coated particles was examined both at the electrode and regarding their impact on electrochemical performance. This was compared to uncoated graphite particles, which were also processed into electrodes and full cells for characterization. PGA measurements and SEM analysis indicate successful coating of the graphite particles with PVC. Long-term cycling of full cells with PVC-coated graphite (processed into electrodes) demonstrates performance comparable to reference cells with uncoated graphite particles and VC added to the electrolyte. The PVC-coated graphite full cells show a significant improvement in cycling stability compared to cells without any VC.