A battery comprising: a battery outer case; an electrode body; and a terminal joined to a sealing plate at an attaching portion, characterized in that: the battery outer case includes a bottomed case main body which has a flat accommodation space and of which one surface is opened, wherein the sealing plate is attached to the opened surface of the case main body; the electrode body is a flat electrode body, is accommodated in the flat accommodation space of the case main body, and comprises an electrode intermediate part to which the terminal is joined; the terminal includes a base end attached to the sealing plate, an intermediate part extending from the base end toward the electrode intermediate part, along a first surface on a first side of the battery outer case, and a tip end that is joined to a surface on one side of the electrode intermediate part resulting in a pushing force on electrode intermediate part; and in that: the joint at the attaching portion on the sealing plate is biased toward the side where the tip end of the terminal is joined in the width direction of the side surface of the battery outer case, such that when an outer surface of the battery outer case is not constrained, a surface of the electrode body, which is on an opposite side of the battery from where the tip end of the terminal is joined to the electrode intermediate part, is pushed against the battery outer case more strongly than the surface of the electrode body, which is on the same side of the battery as where the tip end of the terminal is joined to the electrode intermediate part. a battery outer case; an electrode body; and a terminal joined to a sealing plate at an attaching portion, characterized in that: the battery outer case includes a bottomed case main body which has a flat accommodation space and of which one surface is opened, wherein the sealing plate is attached to the opened surface of the case main body; the electrode body is a flat electrode body, is accommodated in the flat accommodation space of the case main body, and comprises an electrode intermediate part to which the terminal is joined; the terminal includes a base end attached to the sealing plate, an intermediate part extending from the base end toward the electrode intermediate part, along a first surface on a first side of the battery outer case, and a tip end that is joined to a surface on one side of the electrode intermediate part resulting in a pushing force on electrode intermediate part; and in that: the joint at the attaching portion on the sealing plate is biased toward the side where the tip end of the terminal is joined in the width direction of the side surface of the battery outer case, such that when an outer surface of the battery outer case is not constrained, a surface of the electrode body, which is on an opposite side of the battery from where the tip end of the terminal is joined to the electrode intermediate part, is pushed against the battery outer case more strongly than the surface of the electrode body, which is on the same side of the battery as where the tip end of the terminal is joined to the electrode intermediate part. the battery outer case includes a bottomed case main body which has a flat accommodation space and of which one surface is opened, wherein the sealing plate is attached to the opened surface of the case main body; the electrode body is a flat electrode body, is accommodated in the flat accommodation space of the case main body, and comprises an electrode intermediate part to which the terminal is joined; the terminal includes a base end attached to the sealing plate, an intermediate part extending from the base end toward the electrode intermediate part, along a first surface on a first side of the battery outer case, and a tip end that is joined to a surface on one side of the electrode intermediate part resulting in a pushing force on electrode intermediate part; and in that: the joint at the attaching portion on the sealing plate is biased toward the side where the tip end of the terminal is joined in the width direction of the side surface of the battery outer case, such that when an outer surface of the battery outer case is not constrained, a surface of the electrode body, which is on an opposite side of the battery from where the tip end of the terminal is joined to the electrode intermediate part, is pushed against the battery outer case more strongly than the surface of the electrode body, which is on the same side of the battery as where the tip end of the terminal is joined to the electrode intermediate part.