This review discusses recent advancements in hybrid energy storage systems (HESS) for enhancing the integration of renewable energy (RE) into the grid. The global energy sector is undergoing a transformation driven by the increasing demand for clean, sustainable, and reliable energy solutions. However, integrating RE sources such as wind, solar, and hydropower presents challenges due to their intermittent and variable nature, which affects grid stability and reliability. HESS, which combines multiple energy storage devices (ESDs), offers a promising solution by leveraging the complementary strengths of each technology involved. This review examines recent advancements in grid-connected HESS, focusing on their components, design considerations, control strategies, and applications. It provides a detailed analysis of technological progress in various ESDs and the critical role of power conversion, control, energy management, and cooling systems in optimizing HESS performance. Case studies of successful HESS implementations are highlighted to illustrate practical applications and identify benefits and challenges. By addressing these challenges, HESS can significantly enhance the efficiency and reliability of RE, supporting the shift towards a sustainable and resilient energy infrastructure. The paper concludes by identifying future research directions, highlighting the development of intelligent control systems, sustainable materials, and efficient recycling processes to ensure the widespread adoption and long-term viability of HESS.This review discusses recent advancements in hybrid energy storage systems (HESS) for enhancing the integration of renewable energy (RE) into the grid. The global energy sector is undergoing a transformation driven by the increasing demand for clean, sustainable, and reliable energy solutions. However, integrating RE sources such as wind, solar, and hydropower presents challenges due to their intermittent and variable nature, which affects grid stability and reliability. HESS, which combines multiple energy storage devices (ESDs), offers a promising solution by leveraging the complementary strengths of each technology involved. This review examines recent advancements in grid-connected HESS, focusing on their components, design considerations, control strategies, and applications. It provides a detailed analysis of technological progress in various ESDs and the critical role of power conversion, control, energy management, and cooling systems in optimizing HESS performance. Case studies of successful HESS implementations are highlighted to illustrate practical applications and identify benefits and challenges. By addressing these challenges, HESS can significantly enhance the efficiency and reliability of RE, supporting the shift towards a sustainable and resilient energy infrastructure. The paper concludes by identifying future research directions, highlighting the development of intelligent control systems, sustainable materials, and efficient recycling processes to ensure the widespread adoption and long-term viability of HESS.