Energy storage device

An electrode assembly of an energy storage device, the electrode assembly comprising:

• at least one positive electrode;
• at least one negative electrode which is stacked alternately with the positive electrode;
• and
• a separator including a base material layer and an inorganic layer which overlaps with the base material layer,
• wherein the separator is arranged between the positive electrode and the negative electrode,
• wherein the base material layer of the separator directly faces the negative electrode such that the negative electrode is disposed between the positive electrode and the base material layer of the separator,
• wherein the base material layer of the separator is directly exposed to at least one of negative electrodes arranged at an end of the electrode assembly in a stacking direction of the positive electrode and the negative electrode, and
• wherein, in the stacking direction, the inorganic layer of the separator is exposed outside of the electrode assembly.

An energy storage device, comprising:

• an electrode assembly which includes:
• at least one positive electrode;
• at least one negative electrode which is stacked alternately with the positive electrode;
• and
• a strip-like elongated separator including a first base material layer and a first inorganic layer which is configured to overlap with the first base material layer,
• wherein the elongated separator is arranged between the positive electrode and the negative electrode,
• wherein the first base material layer of the elongated separator is configured to face the negative electrode in a directly opposed manner between the positive electrode and the negative electrode,
• wherein positive electrodes and negative electrodes form a plurality of electrode portions which respectively include at least one of the positive electrode and the negative electrode,
• wherein the plurality of electrode portions are arranged in a row in a stacking direction of the positive electrodes and the negative electrodes,
• wherein the electrode portions, which are arranged adjacently to each other, are configured such that the positive electrode of one of the electrode portions and the negative electrode of an other one of the electrode portions face each other in an opposed manner,
• wherein the plurality of electrode portions include a first electrode portion arranged at a center portion in the stacking direction, and a second electrode portion which includes remaining electrode portions,
• wherein electrodes arranged at both ends of the first electrode portion in the stacking direction have a same polarity,
• wherein electrodes arranged at both ends of the second electrode portion in the stacking direction have different polarities,
• wherein the elongated separator is arranged in a spiral shape such that the elongated separator surrounds the first electrode portion and passes between respective electrode portions as viewed in a direction orthogonal to the stacking direction,
• wherein, between the electrode portions, the first base material layer of the elongated separator is configured to face the negative electrode positioned at an end of the electrode portion in the stacking direction in an opposed manner, and
• wherein, in the stacking direction, each of the negative electrodes of the electrode assembly is located adjacent to and is directly exposed to the first base material layer of the elongated separator.