Toward Solid-State 3D-Microbatteries Using Functionalized Polycarbonate-Based Polymer Electrolytes

摘要

3D microbatteries (3D-MBs) impose new demands for the selection, fabrication, and compatibility of the different battery components. Herein, solid polymer electrolytes (SPEs) based on poly(trimethylene carbonate) (PTMC) have been implemented in 3D MB systems. 3D electrodes of two different architectures, LiFePO4-coated carbon foams and Cu2O-coated Cu nanopillars, have been coated with SPEs and used in Li cells. Functionalized PTMC with hydroxyl end groups was found to enable uniform and well-coveting coatings on LiFePO4-coated carbon foams, which was difficult to achieve for nonfunctionalized polytnerS, but the cell cycling performance was limited. By employing a SPE prepared,from a copolymer of TMC and caprolactone (CL), with higher ionic conductivity, Li cells composed, of Cu2O-coated Cu nanopillars were constructed and tested both at ambient temperature and 60 degrees C. The footprint areal capacity of the cells was Ca. 0.02 mAh cm(-2) for an area gain factor (AF),of 2.5, and 0.2 mAh cm(-2) for a relatively dense nanopillar-array (AF = 25) at a current density of 0.008 mA cm(-2) under ambient temperature (22 1 degrees C). These results provide new routes toward the realization of all-solid-state 3D-MBs.