Lithiation and Delithiation Behaviors of the Li-Cu Porous Anode in Li-Metal Battery System

Abstract

The demand for High-energy-density batteries is rapidly increasing due to fast evolution of portable electronic devices, electric cars and energy storage systems. Lithium ion battery system based on graphite anode has made a lot of progress, however, it has almost reached its limit with the low theoretical capacity. Lithium metal anode has the advantages of high theoretical specific capacity (3860mAhg-1) and lowest electrochemical potential voltage (-3.04V vs standard hydrogen electrode). However, the commercialization of lithium metal is still hindered by several inherent challenges such as inhomogeneous lithium dendrites and huge volume expansion during deposition and dissolution. In this study, a use of the pore between Li and Cu powder for stable Li deposition without volume changes from commercially available cathode materials like NCM is investigated. In this system, binder-free anode is facilely and simply fabricated by pressing the well-mixed two powders of similar size. The effect of pore space created by adjusting the pressure on battery performance is verified. A utilization of Li powder induces controllable and uniform dendrite growth because the current density per unit area is lowered by increasing the specific surface area. Inert Cu powder not only leads to localize Lithium deposition, but also maintains a robust skeleton without volume changes. The lithiation and delithiation behavior of Li-Cu porous anode are thoroughly studied by material characterizations and electrochemical properties