Masanao Tanaka

Silica-Composite Nonwoven Separators for Lithium-Ion Battery: Development and Characterization

We have developed silica-composite nonwovens using polyolefin fiber and nanosize silica powder. The silica-composite nonwoven showed better wettability than the polyolefin-based microporous membrane and nonwoven. It was found that the Gurley value of the silica-composite nonwoven has to be higher than 200 s 100 cm -3 in order to suppress a microshort of battery. It was confirmed that the silica-composite nonwovens showed higher maximum power than that of the Celgard membrane by instantaneous discharging test. The cells with the silica-composite nonwovens showed better cycling performances than that of the Celgard membrane at a moderate C-rate of 0.5. A hot-oven test using charged cells up to 4.2 V exhibited that the cells with the silica-composite nonwovens are thermally stable at 150°C, whereas the cell with the Celgard membrane showed a short circuit probably due to thermal shrinkage of the separator.

Ammonia Gas Deodorization Characteristics for Poly(vinyl chloride)-Iron Chloride Chelate.

塩化第一鉄および塩化第二鉄とポリビニルアルコール (PVA), ポリ酢酸ビニル, ポリアクリル酸, ナイロンとの複合体のアンモニアガスの吸着特性について調べた. 塩化第二鉄はPVAと混合すると, 単独のものより吸着速度および飽和吸着量が増大した. 塩化第一鉄はこのような効果はなかった. その他のポリマーの中でポリアクリル酸は塩化第一鉄に対して同じような効果があったが飽和吸着量は塩化第二鉄とPVAを混合した場合より少なかった. その他の樹脂は吸着特性にあまり大きな影響を与えなかった. 塩化第二鉄-PVA複合体は用いたものの中で最大の吸着速度と飽和吸着量を示し, 市販の脱臭剤のアンモニア吸着特性より優れていた.