This study addresses the development of advanced anode materials for lithium-ion batteries by investigating the high-entropy perovskite La(Co0.2Mn0.2Fe0.2Ni0.2Cu0.2)O3. The material was synthesized via spray drying of aqueous metal nitrate solutions, followed by calcination at various temperatures (800 °C/1 h, 1000 °C/1 h, 1000 °C/2 h, 1100 °C/1 h) to optimize structural properties. Structural analysis using X-ray diffraction confirmed the formation of a single-phase perovskite in the sample calcined at 1100 °C for 1 h, while SEM/EDS revealed homogeneous elemental distribution. Electrochemical testing of the powders as anode materials in coin-type lithium-ion cells revealed a trend of slightly increasing capacity over 150 cycles, with capacity ultimately reaching 617 mAh g−1, indicating progressive electrochemical activation. Although the samples share the same composition, variations in calcination conditions resulted in differences in capacity and cycling behavior. These results demonstrate that synthesis parameters critically influence the electrochemical performance of high-entropy perovskites. The findings suggest that such materials have potential as stable anodes for next-generation lithium-ion batteries, contributing to improved durability and efficiency in energy-storage technologies.