Beyond 1 Wh primary coin cells enabled by ultrathick solvent-free processing electrodes

The imperative pursuit of elevated energy density in lithium primary coin cells (LPCCs) necessitates strategic architectural optimization to align with evolving market demands. A predominant approach involves the systematic replacement of metallic structural support components (MSSCs) to minimize non-active constituent ratios, contingent upon maintaining robust interfacial contact integrity among electrodes, separators, and battery shells. Herein, we present a novel LPCC configuration employing solvent-free processed ultra-thick fluorinated carbon cathode (UCF_xC) to achieve complete MSSCs elimination. The engineered UCF_xC demonstrates exceptional areal capacity metrics (249.45 mg cm⁻², 215.77 mAh cm⁻²), enabling a 27.8% mass reduction compared with conventional laboratory-assembled coin cell while achieving 941.5% energy density enhancement through optimized electrode conductivity. Notably, single-walled carbon nanotube (SWCNT)-modified UCF_xC architectures exhibited superior performance with energy exceeding 1.0 Wh at 50 °C. This architectural paradigm provides valuable insights for developing next-generation high-energy-density LPCC systems, with practical implications for advancing miniaturized power source technologies.