Lithium metal anodes are considered a key enabler for next-generation high-energy-density batteries due to their high theoretical capacity and low electrochemical potential. However, the growth of lithium dendrites during cycling poses significant challenges, including short circuits, capacity loss, and safety hazards. To address these issues, researchers have developed physical and chemical strategies to suppress dendrite formation, focusing on pulsed charging, pressure application, and lithiophilic coatings. These approaches aim to stabilize the lithium-electrolyte interface and promote uniform lithium deposition.

Pulsed charging is an electrochemical strategy that modulates the current or voltage during charging to influence lithium deposition behavior. Unlike constant current charging, pulsed charging introduces rest periods or alternating current profiles that allow for relaxation of concentration gradients and redistribution of lithium ions. Experimental studies have demonstrated that high-frequency pulsed charging can reduce dendrite formation by promoting smoother lithium morphology. For example, a study applying square-wave pulses with a frequency of 1 kHz showed a threefold improvement in cycle life compared to conventional charging. Modeling work has further supported these findings, revealing that pulsed charging reduces localized ion depletion near the electrode surface, mitigating uneven lithium plating. The effectiveness of pulsed charging depends on parameters such as pulse frequency, duty cycle, and amplitude, which must be optimized for specific battery configurations.

Mechanical pressure application is another physical approach to suppress dendrite growth. Applying external pressure compresses lithium deposits, reducing porosity and increasing the density of the plated metal. Research has shown that pressures in the range of 0.5 to 2 MPa can significantly enhance cycling stability by promoting planar lithium growth instead of dendritic structures. Higher pressures can also improve interfacial contact between lithium and solid electrolytes, though excessive pressure may induce mechanical degradation of battery components. Experimental studies using stack pressure cells have demonstrated that uniform pressure distribution is critical for preventing localized stress concentrations that could exacerbate dendrite formation. Computational models have further elucidated the relationship between pressure and lithium morphology, indicating that moderate pressure levels homogenize the electric field at the electrode surface, leading to more uniform deposition.

Lithiophilic coatings represent a chemical strategy to control lithium deposition by modifying the surface properties of the current collector or separator. These coatings consist of materials with high affinity for lithium, such as metals, alloys, or compounds that reduce nucleation barriers and guide uniform plating. For instance, coatings of gold, silver, or zinc oxide have been shown to lower the overpotential for lithium nucleation, resulting in dense and dendrite-free deposits. Recent work has explored nanostructured lithiophilic coatings, where high-surface-area architectures provide abundant nucleation sites, further improving deposition uniformity. Additionally, some coatings exhibit self-healing properties, where dynamic interactions with lithium ions continuously repair defects during cycling. Advanced characterization techniques, such as in-situ microscopy, have revealed that lithiophilic coatings can redirect lithium growth along preferential crystallographic orientations, minimizing dendritic protrusions.

Combining these approaches has shown promise in achieving synergistic effects. For example, pulsed charging paired with lithiophilic coatings can enhance the uniformity of lithium deposition by simultaneously optimizing ion transport and nucleation kinetics. Similarly, applying pressure alongside surface modifications can further suppress dendrite penetration by mechanically stabilizing the lithium-electrolyte interface. Recent experimental studies on hybrid systems have reported cycle life extensions exceeding 500 cycles with minimal capacity fade, demonstrating the potential of integrated strategies.

Despite these advances, challenges remain in scaling up these techniques for practical applications. Pulsed charging requires sophisticated power electronics, which may increase system complexity and cost. Pressure application demands robust cell designs capable of maintaining uniform mechanical loads over extended cycling. Lithiophilic coatings must be economically viable and compatible with large-scale manufacturing processes. Future research is expected to focus on optimizing these methods for commercial battery systems while maintaining performance and safety standards.

In summary, suppressing lithium dendrites requires a multifaceted approach that addresses both the electrochemical and mechanical aspects of lithium deposition. Pulsed charging, pressure application, and lithiophilic coatings each offer unique advantages, and their combination presents a viable pathway toward stable lithium metal anodes. Continued advancements in experimental techniques and modeling will further refine these strategies, paving the way for high-performance lithium metal batteries.