Hexagonal boron nitride (h-BN) is a versatile two-dimensional material that has attracted significant attention for energy applications. Surface modification of Hexagonal Boron Nitride Nanosheets (BNNS) is a crucial aspect of enhancing their properties and expanding their applications. It also enhances the compatibility of h-BN with different matrices and facilitates its integration into various composite materials. The main objective of this research work is to modify the surface of BNNS using Lithium stearate (LiC18H35O2), denoted as LS. Three different combinations of BNNS and LS blends, designated as BNLS1 (BNNS: LS at 1:1), BNLS2 (BNN: LS at 1:2), and BNLS3 (BNNS: LS at 1:3), have been prepared. As a surface modifier, LiC18H35O2 imparts specific characteristics to surfaces or interfaces. The obtained samples underwent characterization techniques such as X-ray powder diffraction (XRD), UV-visible spectroscopy (UV-Vis), Fourier-transform infrared (FTIR) spectroscopy, Thermogravimetric analysis (TGA), Raman spectroscopy, and Photoluminescence (PL) analysis. The reduction of the optical bandgap in BNNS following functionalization is examined and discussed. The thermal stability of the surface-modified samples is explored, and the onset degradation temperature of BNLS3 is very high compared to that of pure BNNS. These enhanced properties make the composites an appropriate material for electrochemical storage applications.