Power storage device

A power storage device, comprising:

• an electrode assembly having a multi-layer structure in which a positive electrode and a negative electrode are insulated from and laminated with each other;
• a battery can that accommodates the electrode assembly;
• a positive electrode terminal that takes out electricity from the positive electrode;
• and
• a negative electrode terminal that takes out electricity from the negative electrode, wherein
• the positive electrode terminal includes:
• an internal terminal that is electrically connected with the positive electrode and accommodated in the battery can;
• and
• an external terminal that is partially exposed outside the battery can,
• the positive electrode includes a positive electrode metallic thin plate and a positive electrode active material layer formed by coating the positive electrode metallic thin plate with a positive electrode active material,
• a positive electrode electricity collecting portion that is a portion not coated with the positive electrode active material is formed on the positive electrode metallic thin plate,
• the positive electrode electricity collecting portion includes a positive electrode connecting portion serving as a connection portion with the positive electrode terminal and extends from one end of the positive electrode,
• the negative electrode terminal includes:
• an internal terminal that is electrically connected with the negative electrode and accommodated in the battery can;
• and
• an external terminal that is partially exposed outside the battery can,
• the negative electrode includes a negative electrode metallic thin plate and a negative electrode active material layer formed by coating the negative electrode metallic thin plate with a negative electrode active material,
• a negative electrode electricity collecting portion that is a portion not coated with the negative electrode active material is formed on the negative electrode metallic thin plate,
• the negative electrode electricity collecting portion includes a negative electrode connecting portion serving as a connection portion with the negative electrode terminal and extends from one end of the negative electrode,
• when a width direction of a layer portion that is a region in which the positive electrode active material layer and negative electrode active material layer overlap in the electrode assembly is assumed to be a direction orthogonal to a direction in which the positive electrode electricity collecting portion and the negative electrode electricity collecting portion extend, a line that passes through a center of the electrode assembly in the width direction of the layer portion and extends in a direction in which the positive electrode electricity collecting portion and the negative electrode electricity collecting portion extend is defined as an imaginary reference line,
• when a width direction of the positive electrode electricity collecting portion is assumed to be a direction orthogonal to a direction in which the positive electrode electricity collecting portion extends, a line that passes through a center of the positive electrode electricity collecting portion in the width direction of the positive electrode electricity collecting portion and extends in a direction in which the positive electrode electricity collecting portion extends is defined as a first imaginary central line,
• when a width direction of the negative electrode electricity collecting portion is assumed to be a direction orthogonal to a direction in which the negative electrode electricity collecting portion extends, a line that passes through a center of the negative electrode electricity collecting portion in the width direction of the negative electrode electricity collecting portion and extends in a direction in which the negative electrode electricity collecting portion extends is defined as a second imaginary central line,
• a distance between the imaginary reference line and the first imaginary central line in the width direction of the layer portion is different from a distance between the imaginary reference line and the second imaginary central line in the width direction of the layer portion, so that the electrode assembly has an asymmetric structure, and
• one of the two connecting portions that is positioned near the imaginary reference line is arranged at a position in the wide direction of the layer portion inside of one of the two external terminals that is electrically connected with the connecting portion.

A power storage device, comprising:

• an electrode assembly having a multi-layer structure in which a positive electrode and a negative electrode are insulated from and laminated with each other;
• a battery can that accommodates the electrode assembly;
• a positive electrode terminal that takes out electricity from the positive electrode;
• and
• a negative electrode terminal that takes out electricity from the negative electrode, wherein
• the positive electrode terminal includes:
• an internal terminal that is electrically connected with the positive electrode and accommodated in the battery can;
• and
• an external terminal that is partially exposed outside the battery can,
• the positive electrode includes a positive electrode metallic thin plate and a positive electrode active material layer formed by coating the positive electrode metallic thin plate with a positive electrode active material,
• a positive electrode electricity collecting portion that is a portion not coated with the positive electrode active material is formed on the positive electrode metallic thin plate,
• the positive electrode electricity collecting portion includes a positive electrode connecting portion serving as a connection portion with the positive electrode terminal and extends from one end of the positive electrode,
• the negative electrode terminal includes:
• an internal terminal that is electrically connected with the negative electrode and accommodated in the battery can;
• and
• an external terminal that is partially exposed outside the battery can,
• the negative electrode includes a negative electrode metallic thin plate and a negative electrode active material layer formed by coating the negative electrode metallic thin plate with a negative electrode active material,
• a negative electrode electricity collecting portion that is a portion not coated with the negative electrode active material is formed on the negative electrode metallic thin plate,
• the negative electrode electricity collecting portion includes a negative electrode connecting portion serving as a connection portion with the negative electrode terminal and extends from one end of the negative electrode,
• when a width direction of a layer portion that is a region in which the positive electrode active material layer and negative electrode active material layer overlap in the electrode assembly is assumed to be a direction orthogonal to a direction in which the positive electrode electricity collecting portion and the negative electrode electricity collecting portion extend, a line that passes through a center of the electrode assembly in the width direction of the layer portion and extends in a direction in which the positive electrode electricity collecting portion and the negative electrode electricity collecting portion extend is defined as an imaginary reference line,
• when a width direction of the positive electrode connecting portion is assumed to be a direction orthogonal to a direction in which the positive electrode electricity collecting portion extends, a line that passes through a center of the positive electrode connecting portion in the width direction of the positive electrode connecting portion and extends in a direction in which the positive electrode electricity collecting portion extends is defined as a first imaginary connection central line,
• when a width direction of the negative electrode connecting portion is assumed to be a direction orthogonal to a direction in which the negative electrode electricity collecting portion extends, a line that passes through a center of the negative electrode connecting portion in the width direction of the negative electrode connecting portion and extends in a direction in which the negative electrode electricity collecting portion extends is defined as a second imaginary connection central line,
• a distance between the imaginary reference line and the first imaginary connection central line in the width direction of the layer portion is different from a distance between the imaginary reference line and the second imaginary connection central line in the width direction of the layer portion, so that the electrode assembly has an asymmetric structure, and
• one of the two connecting portions that is positioned near the imaginary reference line is arranged at a position in the wide direction of the layer portion inside of one of the two external terminals that is electrically connected with the connecting portion.