Hydrogels and microgels are emerging as pivotal platforms in biomedicine, with significant potential in targeted drug delivery, enhanced infection management, and tissue repair and regeneration. These gels, characterized by their high water content, unique structures, and adaptable mechanical properties, interact seamlessly with biological systems, making them invaluable for controlled and targeted drug release. In the realm of infection management, hydrogels and microgels can incorporate antimicrobial agents, offering robust defenses against bacterial infections. This capability is increasingly important in the fight against antibiotic resistance, providing innovative solutions for infection prevention in wound dressings, surgical implants, and medical devices. Additionally, the biocompatibility and customizable mechanical properties of these gels make them ideal scaffolds for tissue engineering, supporting the growth and repair of damaged tissues. Despite their promising applications, challenges such as ensuring long-term stability, enhancing therapeutic agent loading capacities, and scaling production must be addressed for widespread adoption. This review explores the current advancements, opportunities, and limitations of hydrogels and microgels, highlighting research and technological directions poised to revolutionize treatment strategies through personalized and regenerative approaches.

The advancement of battery technology has been impeded by the voltage constraints of electrolytes. Here, we present a high-energy all-solid-state battery (ASSB) design that achieves both a >5 V operation and an ultrahigh areal capacity of 35.3 mAh cm-2; these attributes were enabled by a new, highly conductive and ultrahigh voltage stable fluoride solid electrolyte (SE), LiCl–4Li2TiF6 (1.7 x 10-5 S cm-1 at 30 °C). This material provides over 100 times higher Li+ conductivity than Li2TiF6, attributable to the enlarged Li+ channels and increased Li+ concentration at the nanocrystallite interfaces, as proved by combined experimental and theoretical investigations. LiCl–4Li2TiF6 shields high-voltage spinel oxide cathodes, achieving excellent performance (e.g., 106 mAh g-1 at 2C and 30 °C with 75.2% retention after 500 cycles for LiNi0.5Mn1.5O4), sharply contrasting with the conventional LiNbO3 counterpart, which decomposes and fails to prevent detrimental interfacial degradation. The efficacy of LiCl–4Li2TiF6 is validated across various systems, including higher-voltage LiCoMnO4, cost-effective LiFe0.5Mn1.5O4, pouch-type LiNi0.5Mn1.5O4//Li ASSBs, operability down to 2.3 V with 258 mAh g-1, and 1.8 mm ultrathick electrodes. This newly proposed SE with over 5 V stability introduces a new design paradigm by revisiting the previously forbidden high-voltage cathodes for high-energy ASSBs.