リチウムイオン二次電池負極用スラリー分散過程の粘弾性解析

摘要

粒子分散液の中でも懸濁密度が高く，高粘度を示す場合をスラリーと呼ぶことが多い。スラリーは様々な化学工業プロセスにおいて取り扱われ，例えばスラリーの塗布•乾燥による薄膜製造プロセスを経て燃料電池の触媒膜やリチウムイオン二次電池の電極膜が作製されている。しかしながら，プロセスの効率化や収量増大を目的とした超濃厚系へのシフトや水溶媒への変更はプロセス構築において様々な課題を抱えている。%The structural change during particle dispersion process of highly concentrated slurries of PMMA and graphite particles was investigated in terms of viscoelasticity. PMMA particles having weak interaction are easy to be dispersed, and a higher shear rate was preferable for stable dispersion. In contrast, aggregated graphite particles generate sedimentation layer. Therefore, non-uniform slurry was obtained at the lowest shear rate, while the formation of network of aggregated graphite particles resulted in a highly viscoelastic slurry when dispersing at higher shear rates. Additionally, it was considered that the particle dispersion is completed at the shear rate, when the loss moduli of slurry and dispersing medium showed the same frequency dependence.