| 摘要 |
PURPOSE:To restrict the rise of the inner pressure of a battery and to prevent the oxidation of a hydrogen absorption alloy, by arranging an oxidation control layer which consists of a metallic oxide powder and a ceramic powder on the surface of a negative electrode contacting to a positive electrode side, and furnishing an oxygen catalyst layer on the back side of the negative electrode. CONSTITUTION:By furnishing a metallic oxide positive electrode 6, a negative electrode 5 which consists of a hydrogen absorption alloy 2 or a hydrate, a separator 7, and an electrolyte, furnishing an oxidation control layer 3 which consists of a metallic oxide powder and a ceramic powder on the surface of the negative electrode 5 contacting to the positive electrode side, and forming at least two layers of oxygen catalyst layers 4 on the back of the negative electrode 5, the negative electrode 5 itself shall have a catalystic function aud the oxidation control function. In this case, the oxygen catalyst layer 4 is made of at least a carbon powder alone or of a carbon powder inscolding the catalyst, and the porousness is made 30 to 60 %. As a result, even at a relatively large charge rate, the prevention of oxidation by the oxygen gas of the hydrogen absorption alloy composing the negative electrode 5, and the oxygen absorption or the oxygen reducing reaction on the surface of the negative electrode 5 can he exercised efficiently. |
