A concentration gradient structure is introduced to enhance the mechanical and electrochemical stability of Ni-rich cathode materials, addressing issues related to irreversible structural degradation. The study focuses on synthesizing a Ni-rich cathode material, LiNi0.8Co0.1Mn0.1O2 (CG-NCM), with a Mn-rich surface and a Ni-rich core. The Mn-rich surface minimizes parasitic side reactions at the electrode-electrolyte interface, while the Ni-rich core ensures high capacity. The concentration gradient structure also provides mechanical strength through radially aligned primary particles, reducing internal strain and crack propagation during cycling. The CG-NCM cathode delivers a discharge capacity of approximately 180.1 mA h g−1 at 1 C and retains 96.2% of its initial discharge capacity after 100 cycles. The enhanced mechanical properties of CG-NCM, including higher fracture strength and modulus, are attributed to the Mn-rich shell and radially aligned primary particles. The concentration gradient structure also suppresses the H2-H3 phase transition at high voltage, improving cycle stability. Electrochemical tests confirm that CG-NCM exhibits superior long-term durability compared to conventional NCM (C-NCM). The Mn-rich surface inhibits electrolyte penetration and reduces side reactions, contributing to the improved electrochemical performance. The study demonstrates that the concentration gradient structure effectively enhances the mechanical and chemical stability of Ni-rich cathodes, offering a feasible approach for designing high-energy lithium-ion batteries with long cycle life.A concentration gradient structure is introduced to enhance the mechanical and electrochemical stability of Ni-rich cathode materials, addressing issues related to irreversible structural degradation. The study focuses on synthesizing a Ni-rich cathode material, LiNi0.8Co0.1Mn0.1O2 (CG-NCM), with a Mn-rich surface and a Ni-rich core. The Mn-rich surface minimizes parasitic side reactions at the electrode-electrolyte interface, while the Ni-rich core ensures high capacity. The concentration gradient structure also provides mechanical strength through radially aligned primary particles, reducing internal strain and crack propagation during cycling. The CG-NCM cathode delivers a discharge capacity of approximately 180.1 mA h g−1 at 1 C and retains 96.2% of its initial discharge capacity after 100 cycles. The enhanced mechanical properties of CG-NCM, including higher fracture strength and modulus, are attributed to the Mn-rich shell and radially aligned primary particles. The concentration gradient structure also suppresses the H2-H3 phase transition at high voltage, improving cycle stability. Electrochemical tests confirm that CG-NCM exhibits superior long-term durability compared to conventional NCM (C-NCM). The Mn-rich surface inhibits electrolyte penetration and reduces side reactions, contributing to the improved electrochemical performance. The study demonstrates that the concentration gradient structure effectively enhances the mechanical and chemical stability of Ni-rich cathodes, offering a feasible approach for designing high-energy lithium-ion batteries with long cycle life.