Method and apparatus for manufacturing negative electrode for non-aqueous electrolyte secondary battery

An apparatus for allowing a negative electrode precursor of a non-aqueous electrolyte secondary battery to absorb lithium ions, the negative electrode precursor including a current collector made of a conductor and a first active material layer formed on the current collector and a exposed portion being formed by making a part of the current collector be exposed, the apparatus comprising:

• a winding-out portion configured to pull out the negative electrode precursor wound up;
• an electrolytic bath configured to hold a non-aqueous electrolyte solution containing lithium ions and to immerse the pulled-out negative electrode precursor in the non-aqueous electrolyte solution;
• a first electrode disposed in the non-aqueous electrolyte solution and capable of releasing lithium ions;
• a power unit configured to allow an electric current to flow between the first electrode and the negative electrode precursor and to allow the first active material layer to absorb lithium ions;
• a first reference electrode disposed in a vicinity of a portion immersed in the non-aqueous electrolyte solution of the negative electrode precursor;
• a first potential sensor configured to measure a potential of the portion immersed in the non-aqueous electrolyte solution of the negative electrode precursor with respect to the first reference electrode;
• a controller configured to control an amount of lithium ions absorbed by the first active material layer by controlling an electric current flowing between the negative electrode precursor and the first electrode based on the potential, measured by the first potential sensor;
• and
• a winding-up portion configured to wind up the negative electrode precursor treated to absorb lithium ions,
• the apparatus further comprising an immersion roll configured to set a length of a portion of the negative electrode precursor that is inserted in the non-aqueous electrolyte solution in a moving direction of the negative electrode precursor is at least a length of the exposed portion of the current collector in the moving direction of the negative electrode precursor,
• wherein the negative electrode precursor is inserted into the non-aqueous electrolyte solution in a state along the immersion roll.