Stepped electrode assembly having predetermined a reversible capacitance ratio in the interface between electrode units, battery cell and device comprising the same

摘要

There are provided an electrode assembly, and a battery cell, a battery pack, and a device. The electrode assembly includes a combination of two or more types of electrode units having different areas, wherein the electrode units are stacked such that steps are formed, and electrode units are formed such that a positive electrode and a negative electrode face one another at an interface between the electrode units.

主权项

1. An electrode assembly comprising a combination of two or more types of electrode unit having different areas, the two or more types of electrode unit being stacked so as to form a stepped portion therebetween,
wherein a positive electrode and a negative electrode are formed to face each other at an interface between the electrode units, satisfying following Equation 1-2 so that N/P ratio at the interface is balanced:
1≦Nn/Pn≦Nn/Pn+1≦1.2,  Equation 1-2:where n is an integer not less than 1,
Nn is reversible capacitance per unit area of the negative electrode of the electrode unit that is the n-th largest in area, Pn is reversible capacitance per unit area of the positive electrode of the electrode unit that is the n-th largest in area, and Pn+1 is reversible capacitance per unit area of the positive electrode of the electrode unit that is the (n+1)th largest in area.