Challenges and Recent Advances in High Capacity Li‐Rich Cathode Materials for High Energy Density Lithium‐Ion Batteries

Abstract

mismatch between the cathode and anode materials (the cathode capacity is nearly an order of magnitude smaller than the anode capacity) has seriously hindered the development of LIBs. [2] Li-rich cathode materials have been regarded as one of the most promising candidates for next-generation cathode materials for rechargeable LIBs owing to their prominent specific capacity. For instance, in Li-rich Mn-based (LRM) cathode materials with the chemical formula xLi 2 MnO 3 ⋅(1 -x)LiTMO 2 (TM = Ni, Mn, Co, etc.), when x = 0.5, in the form of Li 1.2 Mn 0.54 Co 0.13 Ni 0.13 O 2 , the theoretical capacity of the LRM cathode reaches over 250 mA h g −1 for 1 Li + extraction, and ≈378 mA h g −1 for 1.2 Li + extraction. [3] Furthermore, LRM cathodes reduce the use of expensive Co and have the advantages of low cost, environmental friendliness, and high thermal stability. However, LRM cathode materials have inherent issues, such as low initial Coulombic efficiency (ICE), poor rate capacity, and serious voltage fading, which inhibit their further practical applications. [4] These issues need to be immediately addressed to eliminate range and safety anxiety in the electric consumption market. The development of state-of-the-art characterization techniques has brought new understandings of the origins of these problems. [5] In this case, considerable progress has been made in the evolution of LRM cathode structures and its various reaction mechanisms during long-time cycles, the electrochemical activity of anions, and other aspects. In addition, significant advances have also been made in the novel modification methods for promoting the electrochemical performances of LRM cathode materials as well as other branches of Li-rich cathode materials. Herein, we present a comprehensive review of the recent challenges and prospects in high-capacity Li-rich cathode materials. This paper aims to offer a global and critical perspective on Lirich cathode materials for LIBs, as shown in Figure 1, including an in-depth evaluation of degradation mechanisms, the prevailing modification methods and development trends, application, and future opportunities for LRM electrode materials in full-cells and future solid-state batteries. We intend to provide perspectives on the practical development and application of Li-rich cathode materials have attracted increasing attention because of their high reversible discharge capacity (>250 mA h g −1 ), which originates from transition metal (TM) ion redox reactions and unconventional oxygen anion redox reactions. However, many issues need to be addressed before their practical applications, such as their low kinetic properties and inefficient voltage fading. The development of cutting-edge technologies has led to cognitive advances in theory and offer potential solutions to these problems. Herein, a recent in-depth understanding of the mechanisms and the frontier electrochemical research progress of Li-rich cathodes are reviewed. In addition, recent advances associated with various strategies to promot...

A Self‐Healable Polyelectrolyte Binder for Highly Stabilized Sulfur, Silicon, and Silicon Oxides Electrodes

“…Developing high-capacity electrode materials are extensively proved as the key to improve the energy density of lithium-ion and lithium-metal batteries. [1][2][3][4] Wherein, naturally abundant silicon (Si), silicon oxides, and sulfur (S) stand out as exceptional anode and cathode materials owing to their ultrahigh theoretical capacity and accessible resources. [5][6][7] However, the negative issues existing in these promising electrodes cannot be overlooked either, which critically hamper their large-scale industrial production.…”

Boosting the Electrochemical Performance of Li- and Mn-Rich Cathodes by a Three-in-One Strategy

“…With the rise of electric devices, electric vehicles and large grid energy storage, etc., the lithium-ion batteries (LIBs) industry is developing vigorously [1][2][3][4][5]. However, the development of cathode materials is far below the market expectations, and it is increasingly unable to meet the energy storage demands [6][7][8].…”

“…Due to its high theoretical specific capacity (generally over 300 mAh g −1 ), environmental friendly, low cost and other advantages, the Li-and Mn-rich cathodes (LMR) with the chemical formula of Li 1+x (Ni, Mn, Co) 1−x O 2 have received a lot of attention, and been regarded as one of the most promising cathode material for future LIBs [9][10][11][12]. However, LMR cathodes suffer from severe capacity/voltage fading, poor rate capability, and low initial Coulombic efficiency [1].…”

Li1.2Mn0.54Ni0.13Co0.13O2 nanosheets with porous structure as a high-performance cathode material for lithium-ion batteries

“…4,5 However, lithium-rich layered oxide cathode materials still have great challenges in their large-scale commercial applications, such as relatively poor rate capability, unsatisfactory cycling stability and severe voltage decay on cycling. [6][7][8] It has been well acknowledged that the electrochemical properties of lithium-rich layered oxide cathode materials tightly depend on their morphologies and structures. [9][10][11][12] Therefore, numerous efforts have been made to control the morphologies and structures of lithium-rich layered oxide cathode materials for enhancing the rate capability, improving the capacity retention and reducing the voltage decay.…”