To construct the Li (001) surface supercell we first optimized the unit cell of BCC Li to obtain the lattice constant. These optimizations were conducted using three DFT functionals -PBE-D3, 65-67 rVV10, and r2SCAN 70 -chosen for their relevance to the solvent decomposition benchmark discussed in Section 3.2 (vide infra). The resulting lattice constants along with their cohesive energies are summarized in Table of the SI. The Li (001) surface supercell is then constructed by repeating the optimized unit cell 3×3 times in the surface plane. Thus, the Li (001) surface supercell consists of a total of 6 layers and 54 atoms as shown in Figure . The positions of the Li atoms in the surface slab are then relaxed using DFT keeping the cell dimensions fixed. Adsorption of four different electrolyte molecules are studied, consisting of two solvent molecules: ethylene carbonate (EC), propylene carbonate (PC) and two additive molecules: vinylene carbonate (VC) and fluoroethylene carbonate (FEC). A vacuum layer of 15 Å is included to minimize the interaction between the adsorbed molecules with the periodic image of the bottom layer of the slab. The as-created configuration of the adsorbed molecule on the surface slab is then optimized using DFT keeping the bottom 2 layers of the slab fixed at the bulk spacing. The adsorption energy (E ad ) of the electrolyte molecules at the Li (001) surface is then calculated using Equation :