Realizing superior energy in a full-cell LIB employing a Li-metal anode via the rational design of a Cu-scaffold host structure with an extremely high porosity

Abstract

In this work, a Li-metal anode (LMA) with a high areal capacity of 10 mA h cm−2 is realized through the rational design of a porous Cu scaffold as a Li-metal host, and the effect of the microscopic morphological properties on the deposition/stripping behavior of Li metal is studied. In particular, the required thickness and weight of the scaffold can be dramatically decreased to 80 μm and 7 mg cm−2, respectively, for storing 10 mA h cm−2 of Li due to the extremely high porosity (91%) of the scaffold and the accurate control of the pore size and surface area. With this scaffold, the gravimetric and volumetric capacities of the LMA can be greatly improved (1043 mA h g−1Li+scaffold and 1250 mA h cm−3Li+scaffold), achieving a gravimetric capacity that is higher than that of Si (1001 mA h g−1Si+Cu foil) and graphite (293 mA h g−1graphite+Cu foil) anodes. As a result, our designed double-sided full cell, which employs a highly porous freestanding Cu scaffold and two LiCoO2 (LCO, 5 mA h cm−2) cathodes in one assembly, exhibits a high specific energy (455 W h kg−1) and energy density (904 W h L−1).