| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electrochemical element which exhibits excellent charge characteristics at low temperature, and good productivity. <P>SOLUTION: The electrochemical element includes a positive electrode, a negative electrode, a nonaqueous electrolyte, and a separator. The negative electrode includes a negative electrode mixture layer containing negative electrode active material on one surface or both surfaces of a collector. The separator includes a porous layer (I) formed of a fine porous film mainly containing thermoplastic resin, and a porous layer (II) mainly containing a filler of which a heat resistant temperature is 150°C or higher. The above problem is solved by the electrochemical element which is characterized in that a ratio Ra/Tb of an arithmetic average roughness Ra(μm) of a surface of the negative electrode mixture layer and a thickness Tb(μm) of the porous layer (II) is 0.10-0.27. <P>COPYRIGHT: (C)2011,JPO&INPIT |
