Lithium ion secondary battery and manufacturing method for negative electrode for lithium ion secondary battery

A manufacturing method for a negative electrode for a lithium ion secondary battery, the manufacturing method comprising the steps of:

• preparing a mixture of a negative electrode active material containing a carbon-based material, a negative electrode additive containing a copper oxide, and a binder;
• and
• applying the mixture to a negative electrode current collector;
• wherein the mixture contains the copper oxide in an amount of 0.5 wt % or more and 15 wt % or less based on the total weight of the negative electrode active material and the negative electrode additive, and
• wherein the negative electrode additive has a median diameter smaller than the median diameter of the negative electrode active material and within the range of 1 to 10 μm
• wherein the negative electrode active material comprises electrically connected particulate material that suppresses increases in an internal resistance of the lithium ion secondary battery.

A lithium ion secondary battery comprising:

• a positive electrode comprising a positive electrode mixture containing a positive electrode active material represented by the following formula (1):
• Li1+xMAO2 (1),
• where X satisfies −0.15≤X≤0.15 and MA represents a group of elements including at least one selected from the group consisting of Manganese (Mn), Aluminum (Al), Nickel (Ni), and Cobalt (Co);
• and
• a negative electrode comprising a negative electrode mixture, wherein the negative electrode mixture comprises, as separate particulates:
• containing a negative electrode active material containing electrically connected particulate material that suppresses increases in an internal resistance of the lithium ion secondary battery,
• a negative electrode additive containing a copper oxide, and
• a binder,
• wherein the negative electrode mixture contains the copper oxide in an amount of 0.5 wt % or more and 15 wt % or less based on a total weight of the negative electrode active material and the negative electrode additive, and
• wherein the lithium ion secondary battery comprises a discharging capacity and the internal resistance affected by a low state of charge range.