The interface between ceramic particles and a polymer matrix in a hybrid electrolyte is studied with high spatial resolution by means of esm, an afm-based technique. The electrolyte consists of peo6 and tallz. The individual components are differentiated by their respective contact resonance, esm amplitude and friction signals. The esm signal shows increased amplitudes and higher contact resonance frequencies on the ceramic particles, while lower amplitudes and lower contact resonance frequencies are present on the bulk polymer phase. The amplitude distribution of the hybrid electrolyte shows a broader distribution in comparison to pure peo6. In the direct vicinity of the particles, an interfacial area with enhanced amplitude signals is found. These results are an important contribution to elucidate the influence of the ceramic–polymer interaction on the conductivity of hybrid electrolytes.

Hybrid electrolytes are developed to meet the requirements of safety, performance, and manufacturing for electrolytes suitable for Li-ion batteries with Li-anodes. Recent challenges-in addition to these key properties-emphasize the importance of sustainability. While compromising between these three objectives, the currently available materials are still well below the targeted goals. Three important issues for the design of hybrid electrolytes are (i) the role of the morphology and surface state of the ceramic particles in the polymer matrix, (ii) the dependence of salt concentration and ionic conductivity and, (iii) the effects of substituting part of the polyethylene oxide (PEO), with biopolymers. Electrolyte films were prepared from PEO, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), Li 6.5 La 3 Zr 1.5 Ta 0.5 O 12 (LLZO:Ta), and biopolymers with varying contents of these components by a solution casting method. The films were analyzed with respect to structural and microstructural characteristics by DSC, Raman spectroscopy, and SEM. Ionic conductivity was evaluated by electrochemical impedance spectroscopy. Most interesting, when comparing films with LLZO:Ta versus without, the content of LiTFSI required for the maximum conductivity in the respective systems is different: a higher LiTFSI concentration is required for the former type. Overall, addition of LLZO:Ta as well as partial substitution of PEO by chitosan mesylate or cellulose acetate decrease the ionic conductivity. Thus-at least in the present approaches-a loss in performance is the drawback from attempts to enhance the safety by LLZO:Ta additions and sustainability by biopolymer blending of hybrid electrolytes.