Cylindrical battery

Abstract

The cylindrical battery includes an electrode body with a positive electrode (11) and a negative electrode (12) wound around a separator (13). The negative electrode has a negative electrode tab (21) connected to the middle periphery, and the negative electrode tab is connected to the bottom of the outer can. The cylindrical battery has at least one permeable member (50) with higher permeability to electrolyte than the separator in the positive and negative electrode facing portions separated by the separator. R1 is defined as the ratio of the total volume of the permeable member in the positive and negative electrode facing portions to the area of ​​the inner circumferential region of the negative electrode with the negative electrode tab connected to it, which is closer to the winding start side. R2 is defined as the ratio of the total volume of the permeable member in the positive and negative electrode facing portions to the area of ​​the outer circumferential region other than the inner circumferential region. R1 and R2 satisfy R1 / (R1+R2)>0.5.

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