Patent ID: 10424776

Abstract:
Using the generally used coating method of an active material paste to a metal foil on a 3DF made the electrode properties instable due to residual air inside of the 3DF, and had the risk of causing micro short circuit of the battery due to metal fine powder and the like adhered to the 3DF and the 3DF exposed to the electrode surface. To solve the above-mentioned, the coating of the active material paste to the 3DF was made into a two-step coating process as shown below. Step one removes the air and fills the paste at the same time by applying the paste flow from one side of the 3DF (the first step coating process). Step two coats a new paste onto the surface of the electrode obtained by step one (the second step coating process). This electrode obtained by the two-step coating process hardly has remaining air amount, can uniformly confine metallic power dust or the 3DF itself inside the electrode (the first step coating process), and in addition to this, has the capability of Li ions freely moving between the electrode surface and the depth portion of the electrode through the opening portion formed on the tip portion of the innumerable protrusions of the 3DF, the micro short circuit of the battery due to Li dendrite was prevented even in repeated charge and discharge.