In the relentless pursuit of safer, more efficient, and sustainable battery technologies, recent advancements have spotlighted manganese-rich layered cathode materials as a promising avenue. These cathodes, characterized by their unique quasi-ordered (QO) crystal structures and elevated manganese content, are showing remarkable improvements in thermal stability, a key parameter that has long challenged the development of next-generation lithium-ion batteries. This breakthrough offers an intriguing blueprint for overcoming safety concerns while paving the way for high-energy, long cycle-life batteries optimized for electric vehicles and large-scale energy storage.
One of the primary challenges with conventional cathode chemistries, especially those rich in nickel and cobalt such as NCM (nickel-cobalt-manganese) variants, has been their tendency to undergo violent exothermic reactions when charged to high voltages. These reactions typically start around the 180 to 240 degrees Celsius range, rapidly releasing substantial heat that can trigger thermal runaway scenarios. The phenomenon not only presents a safety hazard but also complicates thermal management in practical applications. However, researchers have now demonstrated that introducing a manganese-rich surface layer into layered cathodes drastically shifts this thermal profile, significantly enhancing resistance to such exothermic events.
Differential Scanning Calorimetry (DSC) measurements provide compelling evidence of this improvement. When comparing traditional commercial layered cathodes such as NCM50, NCM80, and NCM90 to the newly engineered QO-NCM45 cathode—which contains a higher manganese content—the onset temperature of exothermic reactions is notably delayed. Specifically, the QO-NCM45 cathode exhibited a 15.9-degree Celsius delay in initiating exothermic activity upon charging to 4.6 volts. Even more striking is the intensity of the heat released during these reactions; the QO-NCM45 releases only about 35% of the heat produced by NCM50 under comparable conditions. Such a reduction translates to a far lower risk of rapid thermal propagation, effectively quelling the dangerous self-amplifying thermal cascades that plague current battery designs.
Further backing these findings, Accelerating Rate Calorimetry (ARC) experiments provide a dynamic view of thermal behavior under adiabatic conditions—where the system neither loses nor gains heat from its surroundings. ARC profiles of full cells incorporating QO-NCM cathodes reveal a substantial elevation in critical temperature thresholds. Key markers include T1, the temperature where self-heating commences; T2, the inception point of uncontrollable thermal runaway; and T3, the peak temperature achieved during runaway. Full cells with QO-NCM45 not only show the highest T1 among the tested cathodes, marking the best resistance to initial self-heating, but also display a T2 temperature over 25 degrees Celsius higher than that of the conventional NCM50. This suggests a remarkable structural stability, particularly significant given that oxygen release from cathode materials is often the primary driver of runaway heat generation.
Complementing these thermal advantages, the MN-rich quasi-ordered cathodes demonstrate a mitigated rate of temperature rise during runaway events. Whereas typical commercial cathodes can reach dangerously high peak temperatures, the QO-NCM45 maintains a relatively restrained T3 temperature, providing a vital safety buffer especially in electric vehicle environments where thermal incidents can escalate rapidly. This modulated temperature increase is crucial for designing battery packs that are both safe and capable of delivering high energy density without compromising on longevity or performance.
The chemistry underpinning these thermal improvements is closely linked to the manganese content and its influence on surface reactivity. Mn-rich surfaces tend to be chemically inert and show drastically reduced presence of residual lithium compounds, which are notorious for triggering oxidative electrolyte decomposition and gas evolution at elevated temperatures. Experimental storage-swelling tests conducted at 60 degrees Celsius reveal that the QO-NCM45 cathode evolves considerably less gas compared to traditional NCM cathodes. Reduced gas evolution not only improves battery safety by limiting internal pressure build-up but also enhances cycle life by maintaining the integrity of electrode interfaces over time.
Another remarkable advantage of the QO-NCM45 cathode lies in its manufacturing implications. The negligible amount of residual lithium on the Mn-rich surface means that post-synthesis washing, a costly and complex step commonly required to remove deleterious lithium residues, can be omitted. This streamlined process could significantly reduce production costs and environmental footprint, aligning well with the push towards green manufacturing practices in battery industries. Moreover, the enhanced chemical stability of these cathodes helps minimize transition metal dissolution during storage in highly delithiated states, which is beneficial for maintaining the structural durability of graphite anodes and overall cell longevity.
The structural modifications inherent in the quasi-ordered framework bring additional benefits beyond thermal safety. Although the QO-NCM45 exhibits a relatively thicker cathode-electrolyte interphase due to its larger surface area, the prevalence of Mn4+ on its surface effectively suppresses prolonged cathode-electrolyte degradation under high-voltage cycling conditions. This enhanced interphase stability contributes directly to the sustained electrochemical performance observed during long-term cycling—an indispensable trait for next-generation batteries intended for demanding applications.
Broadly, these innovations point toward a paradigm shift in cathode design philosophy. Historically, the focus has been predominantly on expensive and energy-dense materials containing abundant nickel and cobalt. However, the strategic incorporation of manganese—more abundant, less costly, and less environmentally problematic—into quasi-ordered layered structures signals a move toward balancing performance with sustainability. Not only does this approach promise batteries with higher energy density and extended safety margins, but it also dovetails with the growing imperative to create circular economies in battery materials.
Manganese recycling technology, while currently overshadowed by that for lithium, nickel, and cobalt due to its relatively low market value and resource availability, holds untapped potential that could complement the utilization of Mn-rich cathodes. If recycling infrastructures evolve alongside these novel cathode materials, sustainable battery lifecycles could be realized, greatly alleviating the environmental and economic challenges associated with raw material extraction and end-of-life battery management.
Furthermore, the quasi-ordered Mn-rich cathodes have demonstrated performance consistency across various electrochemical tests, marking them as viable candidates for scaling into commercial applications. Their ability to endure aggressive operational conditions without significant thermal risk or material degradation places them ahead of many conventional alternatives. This research underlines the critical role of material engineering at the atomic and crystal-structure levels in addressing the multifaceted challenges of modern energy storage.
The thermal safety metrics reported here, such as delayed onset of exothermic reactions, reduced heat release, and higher critical temperatures for thermal runaway initiation, are fundamental not only for consumer electronics but are transformative for electric transportation and grid storage technologies. These advancements could significantly reduce the likelihood of battery fires, a major barrier to consumer acceptance and regulatory approval of electric vehicles worldwide.
In summary, the development of zero-strain, manganese-rich, quasi-ordered layered cathodes represents an important leap forward in lithium-ion battery technology. By simultaneously enhancing thermal stability, reducing gas evolution, and improving surface chemistry, these materials address some of the most persistent challenges that have limited lithium-ion batteries’ performance and safety. Their scalable manufacturing advantages and alignment with sustainability goals further underscore their potential impact on the future of energy storage.
The anticipation is high for continued research and development to optimize these cathodes, improve manganese recycling, and integrate these materials successfully into commercial battery systems. As the energy transition accelerates globally, innovations such as the QO-NCM45 cathode could become foundational in delivering the energy density, safety, and sustainability that underpin the next generation of battery-powered technologies.
Subject of Research:
Zero-strain manganese-rich layered cathode materials designed for enhancing thermal stability, safety, and sustainability in lithium-ion batteries.
Article Title:
Zero-strain Mn-rich layered cathode for sustainable and high-energy next-generation batteries.
Article References:
Park, GT., Park, NY., Ryu, JH. et al. Zero-strain Mn-rich layered cathode for sustainable and high-energy next-generation batteries. Nat Energy (2025). https://doi.org/10.1038/s41560-025-01852-3
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Tags: advances in cathode chemistryelectric vehicle battery optimizationexothermic reactions in battery cathodesinnovative battery materials for energy storagelong cycle-life battery materialsmanganese content in battery cathodesmanganese-rich layered cathodesnext-generation battery technologysafety concerns in electric vehicle batteriessustainable battery technologiesthermal runaway prevention in batteriesthermal stability in lithium-ion batteries
