Organic electrode materials offer a versatile, sustainable approach for next-generation lithium-ion batteries but are limited by low working voltages and poor cycling stability. Here we report a solid-solvation-structure design strategy to improve both the voltage and stability of organic electrode materials in all-solid-state batteries. As a proof of concept, we incorporate halide electrolytes as solid solutes and tetrachloro-o-benzoquinone as a solid solvent to form homogeneous solid cathode solutions. Systematic optimization of the inner solvation configuration enables tetrachloro-o-benzoquinone to achieve a high working voltage (3.6 V vs. Li/Li) at room temperature within an asymmetric solid solvation sheath. Moreover, the equilibrium redox pathway and electrostatically driven self-healing interfaces revealed rapid redox kinetics and stable performance over 7,500 cycles in all-solid-state batteries under low stack pressures. This work demonstrates that organic electrode materials can serve as viable, durable and cost-effective alternatives to transition metal oxides in all-solid-state batteries.