Electrochemical device

Provided is a high-power electrochemical device provided with a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode, the negative electrode having a negative electrode mixture layer, the negative electrode mixture layer containing a binder and a negative electrode active material reversibly doped with lithium ions, the negative electrode active material containing difficult-to-graphitize carbon, and the negative electrode active material containing difficult-to-graphitize carbon. The average particle diameter of the binder is 140 nm or more, and the potential of the negative electrode is + 0.2 V or less with respect to the Li counter electrode in a discharge state. 本发明提供一种高功率的电化学器件，该电化学器件具备正极、负极、以及介于正极与负极之间的间隔件，负极具有负极合剂层，负极合剂层包含可逆地掺杂锂离子的负极活性物质和粘结剂，负极活性物质包含难石墨化碳，所述粘结剂的平均粒径为140nm以上，在放电状态下，负极的电位相对于Li对电极为+0.2V以下。