Lattice Engineering on Li2 CO3 -Based Sacrificial Cathode Prelithiation Agent for Improving the Energy Density of Li-Ion Battery Full-Cell

Exploring the Mechanism of Surface Cationic Vacancy Induces High Activity of Metastable Lattice Oxygen in Li- and Mn-Rich Cathode Materials

Li- and Mn-rich layered oxides exhibit high specific capacity due to the cationic and anionic reaction process during high-voltage cycling (≥4.6 V). However, they face challenges such as low initial coulombic efficiency (~70 %) and poor cycling stability. Here, we propose a combination of H3BO3 treatment and low temperature calcination to construct a shell with cationic vacancy on the surface of Li1.2Ni0.2Mn0.6O2 (LLNMO). The H3BO3 treatment produces cationic vacancy and lattice distortion, forming an oxidized On- (0 Collapse

Key Words

• Li-rich cathodes
• cationic vacancy
• coulombic efficiency
• metastable state
• oxygen activation

Collapse

MESH Headings Collapse

Grants

• 22108218 the National Natural Science Foundation of China
• 22105059 the National Natural Science Foundation of China

Collapse

Affiliation(s)

Tian Zhao School of Chemical Engineering and Technology, Xi'an Jiaotong University, No. 28, West Xianning Road, Xi'an, Shaanxi, 710049, China
Jilu Zhang School of Chemical Engineering and Technology, Xi'an Jiaotong University, No. 28, West Xianning Road, Xi'an, Shaanxi, 710049, China Institute for Applied Materials (IAM), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany
Kai Wang School of Materials and Energy, Lanzhou University, No. 222, Tianshui South Road, Lanzhou, 730000, China
Yao Xiao College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, 325035, P. R. China
Qin Wang School of Chemical Engineering and Technology, Xi'an Jiaotong University, No. 28, West Xianning Road, Xi'an, Shaanxi, 710049, China School of Chemical Engineering, Sichuan University, No. 24 South Section 1, Yihuan Road, 610065, Chengdu, China
Longfei Li School of Chemistry, Engineering Research Center of Energy Storage Materials, Devices of Ministry of Education, National Innovation Platform (Center) for Industry-Education Integration of Energy Storage Technology, Xi'an Jiaotong University, Xi'an, 710049, Shanxi, China
Jochi Tseng Diffraction and Scattering Division, Japan Synchrotron Radiation Research Institute (JASRI), 1-1-1, Kouto, Sayo-cho, Sayo-gun, Hyogo, 679-5198, Japan
Meng-Cheng Chen Department of Applied Chemistry and Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu, 300, Taiwan
Jian-Jie Ma Department of Applied Chemistry and Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu, 300, Taiwan
Ying-Rui Lu National Synchrotron Radiation Research Center, Hsinchu, 300, Taiwan
Ishii Hirofumi National Synchrotron Radiation Research Center, Hsinchu, 300, Taiwan
Yu-Cheng Shao National Synchrotron Radiation Research Center, Hsinchu, 300, Taiwan
Xiaoxian Zhao Department of Chemistry, College of Science, Hebei Agriculture University, Baoding, 071001, P. R. China
Sung-Fu Hung Department of Applied Chemistry and Center for Emergent Functional Matter Science, National Yang Ming Chiao Tung University, Hsinchu, 300, Taiwan
Yaqiong Su School of Chemistry, Engineering Research Center of Energy Storage Materials, Devices of Ministry of Education, National Innovation Platform (Center) for Industry-Education Integration of Energy Storage Technology, Xi'an Jiaotong University, Xi'an, 710049, Shanxi, China
Xiaoke Mu School of Materials and Energy, Lanzhou University, No. 222, Tianshui South Road, Lanzhou, 730000, China
Weibo Hua School of Chemical Engineering and Technology, Xi'an Jiaotong University, No. 28, West Xianning Road, Xi'an, Shaanxi, 710049, China Institute for Applied Materials (IAM), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344, Eggenstein-Leopoldshafen, Germany

Collapse

Collaborators Collapse

Unravelling the Oxygen Evolution Mechanism of Lithium-Rich Antifluorite Prelithiation Agent Based on Anionic Oxidation

Developing sacrificial cathode prelithiation technology to compensate for irreversible lithium loss is crucial for enhancing the energy density of lithium-ion batteries. Antifluorite Li-rich Li5FeO4 (LFO) is a promising prelithiation agent due to its high theoretical capacity (867 mAh g-1) and superior decomposition dynamic (<4.0 V vs. Li/Li+). However, the oxygen evolution mechanism in LFO remains unclear, limiting its application as an ideal prelithiation agent. Herein, we systematically track the full lifecycle oxygen footprint in LFO lattice, electrolyte and solid electrolyte interface (SEI). We demonstrate the lattice mismatch induced by the quasi-disorder rocksalt intermediate phase can activate the lattice oxygen oxidation promoting the dimerization to O2. Specifically, in contrast to the O─O dimers formed within typical anionic-redox active cathodes, the oxidation of lattice oxygen in LFO generates O- stabilized in Li6-O configuration. Significantly, a pair of edge-sharing Li6-O configurations transforms into a superoxo dimer, which further evolves into O2 via a ligand-to-metal charge transfer process. Moreover, we demonstrate that nucleophilic intermediates threaten the stability of electrolytes and SEI. Leveraging the insights above, we offer comprehensive perspectives for the modification of ideal prelithiation agents.

Sacrificial Prelithiation Using Different Lithium Salt-Coated LNMO Cathodes for Stabilizing the Electrode Structure and Enhancing Battery Performance

The cobalt-free, high-voltage spinel-type cathode LiNi0.5Mn1.5O4 (LNMO) exhibits high energy and power densities, rendering it a promising candidate for incorporation into next-generation lithium-ion batteries (LIBs). However, its high operating voltage of 4.7 V can lead to electrolyte decomposition, causing structural damage. In addition, the irreversible loss of active lithium in the early cycles reduces capacity performance, hindering its commercial application. To take full advantage of the catalytic effect of LNMO and the prelithiation of sacrificial salt, this work involved blending sacrificial salts (Li2C2O4, Li2CO3, and CH3COOLi) with LNMO to form prelithiated electrodes (LNMO-Sac) and investigating the influence of different sacrificial salts on the performance of LIBs. The results demonstrate that LNMO could efficiently catalyze the decomposition of sacrificial salts and promote the formation of a more stable electrode-electrolyte interface after cycling to mitigate structure destruction of electrodes caused by electrolyte decomposition. Compared with other sacrificial salts, Li2C2O4 provided a highly efficient supplement of active lithium and improved the electrochemical performance of the battery. Thus, LNMO-Li2C2O4 achieved an excellent discharge capacity of 137.9 mAh g-1 at 1C, and capacity retention of 85.9% after 500 cycles, superior to that of LNMO without prelithiation. Moreover, the LNMO-LO/Gr full cell presented an initial capacity of 117.9 mAh g-1 and retained 79.4 mAh g-1 after 300 cycles. This work demonstrates the feasibility of a sacrificial salt as a lithium replenishment strategy for LNMO in practical applications.

A novel cathode Li-supplement additive for high-energy and long-lifespan LIBs

A novel cathode Li-supplement additive, Li4SiO4@rGO, has been developed; it features high capacity (820 mA h g-1), high air stability, and feasible Li-supplement potential (4.3 V). Its integration in NCM622‖graphite improves the energy density by 9% and enhances the capacity retention from 27.5% to 70%. Analogous improvements are also manifested in LFP‖graphite.

Interface Engineering of MOF Nanosheets for Accelerated Redox Kinetics in Lithium-Sulfur Batteries

Modifying the separator is considered as an effective strategy for achieving high performance lithium-sulfur (Li-S) batteries. However, most modification layers are excessively thick, with catalytic active sites primarily located within the material's interior. This configuration severely impacts Li+ transport and the efficient catalytic conversion of polysulfides. Therefore, there is an urgent need to develop a multifunctional separator that integrates ultrathin design, catalytic activity, and ion sieving capabilities. Herein, we successfully linked TCPP(Ni) as a secondary ligand with Zr-BTB nanosheets to create an ultra-thin separator modification layer (Zr-TCPP(Ni)) with efficient ion sieving and catalytic properties. The resultant multifunctional separators provide robust ion sieving capabilities that promote rapid Li+ transport and intercept polysulfides shuttling. Therefore, The Zr-TCPP(Ni)@PP cell maintains 70.0 % of its initial capacity after 600 cycles at a high rate of 3 C, while achieving an impressive areal capacity of 4.55 mA h cm-2 even with high sulfur content of 80 wt% at 0.5 C. This work provides valuable insights for rational design of MOF interface engineering in high energy density Li-S batteries.

Janus-Architectured Lithium Replenishment Separators Boosting Longevity of Anode-Free Lithium Metal Batteries

Addressing the issue of inactive dead lithium deposition on the anode side remains a significant challenge for anode-free lithium metal batteries. While lithium compensation techniques can mitigate lithium depletion, directly introducing lithium compounds into the cathode material may degrade the electrode structure. Here the design and fabrication of a novel lithium replenishment separator (LRS) using a lithium compensation agent of Li2C4O4 is reported. The electrospun LRS demonstrates excellent ionic conductivity of 1.82 mS cm-1 and a high Li+ transference number of 0.51. Such a functionalized LRS not only provides additional active lithium for anode-free lithium metal batteries but also promotes uniform deposition of lithium metal. Compared with conventional polyolefin-based separators, the LRS effectively boosts LiFePO4||Cu anode-free batteries with enhanced cyclability. These results suggest this LRS strategy can find promising applications in next-generation anode-free batteries with high energy densities.

Nanocatalysis in cathode pre-lithiation for lithium-ion batteries: progress and challenges

Pre-lithiation, which is capable of supplying additional active lithium sources to lithium-ion batteries, has been widely accepted as one of the most promising approaches for addressing the issue of active lithium loss during the entire process of initial charging and subsequent cycling. In comparison with anode pre-lithiation, cathode pre-lithiation exhibits a facile operating procedure and good compatibility with current lithium-ion battery production processes. However, cathode pre-lithiation additives suffer from high decomposition voltage and low decomposition efficiency. In view of this, a variety of nanocatalysts have been developed in recent years to enhance the decomposition kinetics of cathode pre-lithiation additives. Nevertheless, a comprehensive review of nanocatalysis in cathode pre-lithiation is still lacking. This timely review aims to present the crucial role of nanocatalysis in cathode pre-lithiation and provide an up-to-date overview of this field. After demonstrating the significance of nanocatalysts for cathode pre-lithiation, recent progress in the application of nanocatalysts for high-efficiency cathode pre-lithiation is briefly introduced. Finally, future challenges and directions for the commercialization of the cathode pre-lithiation technique in conjunction with nanocatalysts are reviewed. The current review provides important insights into nanocatalysis as a cutting-edge strategy for favorable cathode pre-lithiation and builds a bridge between academic research and industrial applications of nanocatalytic cathode pre-lithiation for lithium-ion batteries with high capacity and good cyclability.

Boosting Sodium Compensation Efficiency via a CNT/MnO2 Catalyst toward High-Performance Na-Ion Batteries

The formation of a solid electrolyte interphase on carbon anodes causes irreversible loss of Na+ ions, significantly compromising the energy density of Na-ion full cells. Sodium compensation additives can effectively address the irreversible sodium loss but suffer from high decomposition voltage induced by low electrochemical activity. Herein, we propose a universal electrocatalytic sodium compensation strategy by introducing a carbon nanotube (CNT)/MnO2 catalyst to realize full utilization of sodium compensation additives at a much-reduced decomposition voltage. The well-organized CNT/MnO2 composite with high catalytic activity, good electronic conductivity, and abundant reaction sites enables sodium compensation additives to decompose at significantly reduced voltages (from 4.40 to 3.90 V vs Na+/Na for sodium oxalate, 3.88 V for sodium carbonate, and even 3.80 V for sodium citrate). As a result, sodium oxalate as the optimal additive achieves a specific capacity of 394 mAh g-1, almost reaching its theoretical capacity in the first charge, increasing the energy density of the Na-ion full cell from 111 to 158 Wh kg-1 with improved cycle stability and rate capability. This work offers a valuable approach to enhance sodium compensation efficiency, promising high-performance energy storage devices in the future.