LID AND SEALED BATTERY

To provide a lid in which peeling is not easily generated on a joint surface between a metal member and a seal material.SOLUTION: A lid for closing an opening of a case body of a seal battery includes a terminal member 50 which is a terminal of least one of a positive electrode and a negative electrode, a sealing plate 60 which has a fitting hole 64 for attaching the terminal member, and a sealing member 70 which contains a thermoplastic resin and an inorganic filler. The terminal member is attached to the sealing plate by being inserted into the fitting hole in the state that the sealing member is jointed to a peripheral portion of the fitting hole. As the inorganic filler, an inorganic material containing water of 1200 ppm is used which has a coefficient of cubical expansion of 20% or less after being immersed in a test electrolyte for 7 days, the test electrolyte containing LiPF6 of 1M, having a solvent containing ethylene carbonate, diethyl carbonate, and dimethyl carbonate in a volume ratio of 1:1:1, and being prepared at 65°C.SELECTED DRAWING: Figure 2 【課題】金属部材とシール材の接合面において、剥離が生じにくい蓋体を提供する。【解決手段】密閉型電池のケース本体の開口部を塞ぐ蓋体であって、正極および負極のうち少なくとも一方の電極の端子部材５０と、端子部材を取り付けるための取付穴６４を有する封口板６０と、熱可塑性樹脂および無機フィラーを含んだシール材７０を備える。端子部材は、取付穴の周縁部にシール材が接合された状態で、取付穴に挿通されて、封口板に取り付けられている。ここで、無機フィラーとして、水１２００ｐｐｍを含み、１Ｍ ＬｉＰＦ６を含む試験電解液であって、該試験電解液の溶媒の容積比率がエチレンカーボネート：ジエチルカーボネート：ジメチルカーボネート＝１：１：１である、６５℃に調製された試験電解液に、７日間浸漬した後の体積膨張率が２０％以下であることを特徴とする無機物が使用されている。【選択図】図２