Dian Gao

Bio: Dian Gao is an academic researcher from Chinese Ministry of Education. The author has contributed to research in topics: Current collector & Copper. The author has an hindex of 1, co-authored 1 publications receiving 1 citations. Previous affiliations of Dian Gao include Hefei University of Technology.

Bridging Multiscale Characterization Technologies and Digital Modeling to Evaluate Lithium Battery Full Lifecycle

Abstract: The safety, durability and power density of lithium‐ion batteries (LIBs) are currently inadequate to satisfy the continuously growing demand of the emerging battery markets. Rapid progress has been made from material engineering to system design, combining experimental results and simulations to enhance LIB performance. Limited by spatial and temporal resolution, state‐of‐the‐art advanced characterization techniques fail to fully reveal the complex multi‐scale degradation mechanism in LIBs. Strengthening interaction and iteration between characterization and modeling improves the understanding of reaction mechanisms as well as design and management of LIBs. Herein, a seed cyber hierarchy and interactional network framework is demonstrated to evaluate the overall lifecycle of LIBs. The typical examples of bridging the characterization techniques and modeling are discussed. The critical parameters extracted from multi‐scale characterization can serve as digital inputs for modeling. Furthermore, advanced computational techniques including cloud computing, big data, machine learning, and artificial intelligence can also promote the comprehensive understanding and precise control of the whole battery lifecycle. Digital twins techniques will be introduced enabling the real‐time monitoring and control of LIBs, autonomous computer‐assisted characterizations and intelligent manufacturing. It is anticipated that this work will provide a roadmap for further intensive research on developing high‐performance LIBs and intelligent battery management.

Toward Dendrite-Free Metallic Lithium Anodes: From Structural Design to Optimal Electrochemical Diffusion Kinetics.

Abstract: Lithium metal anodes are ideal for realizing high-energy-density batteries owing to their advantages, namely high capacity and low reduction potentials. However, the utilization of lithium anodes is restricted by the detrimental lithium dendrite formation, repeated formation and fracturing of the solid electrolyte interphase (SEI), and large volume expansion, resulting in severe "dead lithium" and subsequent short circuiting. Currently, the researches are principally focused on inhibition of dendrite formation toward extending and maintaining battery lifespans. Herein, we summarize the strategies employed in interfacial engineering and current-collector host designs as well as the emerging electrochemical catalytic methods for evolving-accelerating-ameliorating lithium ion/atom diffusion processes. First, strategies based on the fabrication of robust SEIs are reviewed from the aspects of compositional constituents including inorganic, organic, and hybrid SEI layers derived from electrolyte additives or artificial pretreatments. Second, the summary and discussion are presented for metallic and carbon-based three-dimensional current collectors serving as lithium hosts, including their functionality in decreasing local deposition current density and the effect of introducing lithiophilic sites. Third, we assess the recent advances in exploring alloy compounds and atomic metal catalysts to accelerate the lateral lithium ion/atom diffusion kinetics to average the spatial lithium distribution for smooth plating. Finally, the opportunities and challenges of metallic lithium anodes are presented, providing insights into the modulation of diffusion kinetics toward achieving dendrite-free lithium metal batteries.

Improving the cycling stability of lithium metal anodes using Cu3N-modified Cu foil as a current collector

Abstract: Lithium (Li) metal anodes have the potential to stimulate the development of secondary batteries due to their high theoretical specific capacities and low redox potentials among all possible solid secondary anode compounds. However, the growth of Li dendrites during repeated Li stripping/plating processes leads to low coulombic efficiencies (CEs) and safety hazards, which significantly hinders their practical application. In this work, commercial Cu foil was modified in situ by Cu3N nanowires (Cu3N NWs/Cu) and used as the current collector for a Li anode. In addition to decreasing the true current density of the anode and alleviating the volume change during the cycles, Cu3N reacted with Li during the initial cycle (3Li + Cu3N → Li3N + 3Cu), which enabled the formation of a Li3N-rich solid electrolyte interphase (SEI). This Li3N-rich SEI with a high ionic conductivity not only boosted Li ion transport but also promoted the homogeneous deposition of Li via increased Li nucleation sites. The improvements in both mass transport and deposition dynamics restrained dendrite growth. As a result, the Cu3N NWs/Cu anode had stable Li plating/stripping over 270 cycles with a high average CE of 98.6% at 1 mA cm−2, with Li capacities of 1 mA h cm−2. A long cycling lifespan of 430 cycles was achieved using a full cell with a high-load LiFePO4 cathode (mass loading: 10 mg cm−2) and a Cu3N NWs/Cu-Li anode (N/P = 2.35), demonstrating the effectiveness and practicality of the Cu3N NWs/Cu current collector in stabilizing the Li anode.