POSITIVE ELECTRODE FOR LITHIUM ION SECONDARY BATTERY, AND LITHIUM ION SECONDARY BATTERY

摘要

The present invention pertains to a positive electrode for a lithium ion secondary battery and to a lithium ion secondary battery containing the same, the present invention addressing the problem of providing a lithium ion secondary battery having high energy density and high output. The above-mentioned problem can be resolved in a positive electrode for a lithium ion secondary battery provided with a positive electrode binder layer containing a positive electrode material and a current collector having the positive electrode binder layer formed on the surface thereof by adopting a configuration in which the positive electrode material contains a first positive electrode active material made of a specific laminar solid solution and a specific second positive electrode active material that reacts at the potential at the end period of electric discharging of the layer solid solution, the positive electrode binder layer in a region in contact with the current collector having a greater proportion of the second positive electrode active material than the first positive electrode active material, and the surface of the positive electrode binder layer opposite to the surface in contact with the current collector having a greater proportion of the first positive electrode active material than the second positive electrode active material.