Lithium-ion batteries, a key driver of modern technology such as smartphones and electric vehicles, are evolving into safer and more efficient forms. Domestic researchers presented a method to maximize the performance of solid electrolytes using a new structure referred to as 'plumber's nightmare.'
Professor Park Mun-jeong and her research team at Pohang University of Science and Technology (POSTECH) announced on the 24th that they have developed a solid electrolyte to enhance the performance of lithium batteries. The research findings were published online in the international journal ACS NANO, issued by the American Chemical Society, on the 3rd.
Lithium-ion batteries are used in various modern technologies, including smartphones. However, the liquid state of the existing electrolytes, one of the key components of batteries, poses risks of leakage and explosion. Solid electrolytes are emerging as an alternative, but there have been limitations in balancing the mechanical strength and ionic conductivity of the electrolytes.
The research team proposed an approach to significantly enhance both the ionic conductivity and mechanical properties of the battery by adding a minuscule amount of lithium salt at less than one-tenth the concentration used in traditional electrolyte manufacturing methods, which previously required concentrations above molarity (M).
The researchers succeeded in creating the sophisticated 'plumber's nightmare' structure, previously unobserved in conventional polymer electrolyte systems. The plumber's nightmare structure is characterized by all the ends of the polymer chains being entangled inward, resembling pipes converging at an outlet. This structure connects six channels formed by the polymer chains, resulting in an environment where lithium ions can travel quickly and efficiently while maintaining a strong and solid electrolyte structure.
Experimental results showed that the plumber's nightmare structure maximized the interaction between the ionic migration pathway and the polymer arrangement, enhancing ionic conductivity efficiency by over 60 times compared to the existing layered structure. This is because lithium ions move along independent pathways, unaffected by the slow movements of the polymer chains. Additionally, the 'energy barrier' that ions must overcome has been reduced by more than tenfold, now comparable to the energy barrier level of traditional inorganic electrolytes. This addresses the conflict between mechanical strength and ionic conductivity, allowing for stable ionic conductivity even at low temperatures.
The results of this research hold significance as they represent a study that presents a method for maximizing lithium-ion battery performance through the plumber's nightmare structure that the research team reported in the international journal Science last year. Professor Park noted, "We established a high-efficiency ionic conduction mechanism by concentrating lithium ions at specific locations of the polymer ends using block copolymers," expressing hope that this research will serve as a turning point for the development of next-generation all-solid-state batteries.
References
ACS NANO (2025), DOI: https://doi.org/10.1021/acsnano.4c13442