High Area Capacity Lithium-Sulfur Full-cell Battery with Prelitiathed Silicon Nanowire-Carbon Anodes for Long Cycling Stability

Abstract

We show full Li/S cells with the use of balanced and high capacity electrodes to address high power electro-mobile applications. The anode is made of an assembly comprising of silicon nanowires as active material densely and conformally grown on a 3D carbon mesh as a light-weight current collector, offering extremely high areal capacity for reversible Li storage of up to 9 mAh/cm2. The dense growth is guaranteed by a versatile Au precursor developed for homogenous Au layer deposition on 3D substrates. In contrast to metallic Li, the presented system exhibits superior characteristics as an anode in Li/S batteries such as safe operation, long cycle life and easy handling. These anodes are combined with high area density S/C composite cathodes into a Li/S full-cell with an ether- and lithium triflate-based electrolyte for high ionic conductivity. The result is a highly cyclable full-cell with an areal capacity of 2.3 mAh/cm2, a cyclability surpassing 450 cycles and capacity retention of 80% after 150 cycles (capacity loss <0.4% per cycle). A detailed physical and electrochemical investigation of the SiNW Li/S full-cell including in-operando synchrotron X-ray diffraction measurements reveals that the lower degradation is due to a lower self-reduction of polysulfides after continuous charging/discharging.

Pre-Lithiation Strategies for Rechargeable Energy Storage Technologies: Concepts, Promises and Challenges

“…These findings have also been assigned to cell failures in Li metal based cells due to HSAL formation, especially in cells with high mass loadings and, therefore, high charge/discharge currents [191,192].…”

“…Several lithium ion host materials like carbons [177][178][179][180][181], Ge [182], Si [183][184][185][186][187] or Si/carbon composites [175,[188][189][190][191][192][193][194], pre-lithiated before cell assembling, are reported as alternative negative electrode materials for the replacement of metallic Li in sulphur cells. Within these reports, mainly two different techniques for the pre-lithiation of the negative electrode were used, namely the electrochemical pre-lithiation and the direct contact to Li metal, as already described above.…”

Research Progress towards Understanding the Unique Interfaces between Concentrated Electrolytes and Electrodes for Energy Storage Applications

“…However, when the S loading is raised to the practical application level (2–4 mAh cm −2 capacity loading), the stability of the Li metal anode then becomes the decisive factor due to its instability with the electrolyte and the continuous growth of resistive SEI on the Li metal surface. While Li anode protection remains a challenge for a long history of Li metal batteries, an alternative approach to avoid the Li metal anode degradation is to resort to the use of Si,58 Sn,59 or carbon anodes 60. Lu et al proved the concept of Li‐ion sulfur batteries employing intercalation graphite compound as the anode.…”

Correlation between Li Plating Behavior and Surface Characteristics of Carbon Matrix toward Stable Li Metal Anodes

“…When the sulfur cathode was integrated into a LSB full cell using a Li-plated SS anode, the battery delivered an initial energy density of 850 Wh kg −1 while an energy of only 150 Wh kg −1 was retained after 100 cycles, corresponding to an energy reduction of 0.82% cycle −1 . [51,52] The cyclic stabilities of the LSB full cells at a high rate were also tested, and the results and relevant discussion can be found in Figure S19 (Supporting Information). This finding is different from the nearly inexhaustible Li supply in the half cell.…”