Enhanced stability and high-rate performance of LiNi0.8Co0.1Mn0.1O2 by surface topological synthesis of rare earth polymetallic oxides coating
Introduction
With the rapid development of various industries, the demand for energy is rapidly increasing. However, the traditional fossil energy such as coal, oil and natural gas are very limited and will produce a large amount of greenhouse gases and other environmental pollutants during the operation [1], [2]. Therefore, clean and renewable energy that can meet energy needs and environment friendly standards has been gradually replaced traditional fossil energy nowadays [3], [4]. Considering the safety, efficiency and convenience of storage, lithium-ion batteries (LIBs) have attracted wide attention and achieved large-scale applications in our daily life [5], [6], [7], [8], [9], [10]. In recent years, the new energy vehicle industry has grown rapidly, which requires LIBs to have better cycle and rate performance but traditional cathode materials can no longer meet the needs [11], [12], [13], [14], [15], [16], [17], [18], [19]. Therefore, we put forward higher requirements to the updated cathode materials of LIBs. Composite cathode material LiNi1−x-yCoxMnyO2 (NCM), which combines the advantages of LiCoO2, LiNiO2 and LiMnO2 with higher capacity, outstanding cycle performance and thermal stability, is considered by researchers to be one of the most promising future cathode materials for LIBs [20], [21], [22]. Among this, LiNi0.8Co0.1Mn0.1O2 (NCM811) has attracted extensive attention for its high capacity in theory, but it also faces many problems, such as sharp decline of cycle performance and high loss in initial capacity, which seriously hinder its commercial application [23], [24].
Due to the multi-stage phase changes occur in cyclic processes, the polarization phenomenon of electrode materials intensifies with the increase of Ni content, which will lead to the volume shrinkage of cathode materials and the destruction of the structure [25], [26]. At present, the mainstreams of modification methods are surface coating and element doping. Surface coating is a simple and effective method which requires coating layer should be stable in electrolyte and can provide conductivity. The coating layer can not only reduce the corrosion on the surface of electrode materials, but also further maintain the structural stability, inhibit the volume change [27], [28]. At present, the major coating material include: coating Li+ conductors such as Li3VO4, Li2ZrO3, LiTiO3, which can avoid the direct contact between cathode material and electrolyte and reduce the side reactions, [29], [30], [31] electronic conductors such as reduced graphene oxide and LiTiO2 to promote electron conduction, improve magnification performance and structural stability,[32], [33], [34] and high-pressure resistance material such as Li2MnO3, Li2SiO3 which can protect the layered structure under high pressure and improve reversible capacity and cycle performance [35], [36]. Doping appropriate metal or non-metal ions into the lattice of high nickel materials can effectively reduce the Li+/Ni2+ mixing phenomenon and stabilize the structure, [37], [38] common doped elements are Mg, Cr, La [39].
In this paper, we modified NCM811 by using rare earth (La, Ho, Tm) polymetallic oxide (REPMO) as coating layer to enhance cycle and rate performance. The REPMO coating can not only protect the active material from electrolyte corrosion to maintain the structural stability, but also promote the conduction of Li+. In addition, the REPMO modified NCM811 has smaller transfer resistance and polarization after modification. We also put forward a new coating synthetic method, high speed shear with reduction. The co-precipitation method is cumbersome and the reaction conditions are strict, [40], [41] and the sol-gel process is complex and costly [42]. For example, the precipitation rate in the process of co-precipitation reaction is difficult to control, which leads to uneven morphology of the obtained products and the sol-gel method requires many consecutive steps in processing. Compared with traditional synthesis methods, our method is simple, efficient, low-cost and can be operated at room temperature. The preparation of the coated precursor can be completed in a very short time with high-speed shear and the initial metal salt solution only requires simple ultrasonic treatment. As a result, after REPMO coating topologically synthesis on the surface of NCM811, the long-cycle and high-rate performance are obviously enhanced.
Section snippets
Materials
The LiNi0.8Co0.1Mn0.1O2 cathode material was purchased from Guangdong Canrd New Energy Technology Co., Ltd. All metal salts powders were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. Ethylene glycol dimethyl ether (DME), AR 99.5%(GC), were purchased from Shanghai Macklin Biochemical Co., Ltd.
Synthesis the precursor of rare earth (La, Ho, Tm) polymetallic oxide (REPMO) modified NCM811
We adopt a method of topological synthesis, which means synthesizing precursor of REPMO modified NCM811 firstly by high speed shear with reduction, and then mixing and sintering to form a
Results and discussion
Fig. 1 illustrates the topological synthesis method schematic diagram of REPMO modified NCM811 process. Firstly, the REPMA as precursor was synthesized and deposited on the surface of NCM811 by high-speed shearing with reduction method. The mechanisms of the liquid NaK alloy for chemical reduction processes of rare earth alloys La, Ho and Tm are shown in Table. S1. Then the REPMO coating was topologically obtained on the surface of NCM811 through the co-sintering of REPMA and LiOH·H2O in air.
Conclusion
A facile and effective coating method is developed for Ni-rich cathode materials. The rare earth (LaHoTm) polymetallic oxide coating layer (REPMO) was successfully synthesized on the surface of NCM811 through a two-step method of a precoating of alloy nanoparticles and subsequent surface topological conversion process. The electrochemical performance of NCM811 @LaHoTm-750–15 has been significantly improved with preeminent long-cycle and high-rate capacity. The LaHoTm REPMO coating layer can not
CRediT authorship contribution statement
Hongbin Feng: Conceptualization, Writing – review & editing, Investigation, Methodology, Writing – original draft. Bingyi Lu: Data curation, Investigation, Methodology, Writing – original draft. Shihang Ma: Investigation, Methodology.
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Acknowledgements
This work was financially supported by the National Natural Science Foundation of China (No. 21501172), the Key Research and Development Programs in Shandong (2018GGX102038), the Applied Basic Research Program Project of Qingdao (No. 17-1-1-69-jch), the World-Class University and Discipline Program of Shandong Province and the Taishan Scholars Advantageous and Distinctive Discipline Program for supporting the research team of energy storage materials of Shandong Province, P. R. China. The
References (53)
- et al.
Renewable energy resources: current status, future prospects and their enabling technology
Renew. Sustain. Energy Rev.
(2014) - et al.
Li ion battery materials: present and future
Mater. Today
(2015) - et al.
Li ion battery materials: present and future
Mater. Today
(2015) Cobalt dissolution in LiCoO2-based non-aqueous rechargeable batteries
Solid State Ion.
(1996)Practical evaluation of Li-Ion
Batter., Joule
(2019)Thermal behavior of Li1–yNiO2 and the decomposition mechanism
Solid State Ion.
(1998)Structure and performance of LiFePO4 cathode materials: a review
J. Power Sources
(2011)- et al.
Improvement of high rate discharging performance of LiFePO4 cathodes by forming micrometer sized through holed electrode structures with a pico second pulsed laser
Electrochim. Acta
(2019) - et al.
Novel lithium insertion material of LiCo1/3Ni1/3Mn1/3O2 for advanced lithium ion batteries
J. Power Sources 119–
(2003) - et al.
Comparison of the structural and electrochemical properties of layered Li[NixCoyMnz]O2 (x=1/3, 0.5, 0.6, 0.7, 0.8 and 0.85) cathode material for lithium ion batteries
J. Power Sources
(2013)
Chemical coupling constructs amorphous silica modified LiNi0.6Co0.2Mn0.2O2 cathode materials and its electrochemical performances
J. Power Sources
Enhanced electrochemical performance of LiNi0.8Co0.1Mn0.1O2 with lithium reactive Li3VO4 coating
J. Alloy. Compd.
Improving the cycling performance of LiNi0.8Co0.1Mn0.1O2 by surface coating with Li2TiO3
Electrochim. Acta
Improved cycle stability of high capacity Ni rich LiNi0.8Mn0.1Co0.1O2 at high cut off voltage by Li2SiO3 coating
J. Power Sources
Improved cyclic stability of LiNi0.8Co0.1Mn0.1O2 via Ti substitution with a cut off potential of 4.5V
Ceram. Int.
Characterization of multiple metals (Cr, Mg) substituted LiNi0.8Co0.1Mn0.1O2 cathode materials for lithium ion battery
J. Alloy. Compd.
Synthetic optimization of Li[Ni1/3Co1/3Mn1/3]O2 via co precipitation
Electrochim. Acta
High capacity Li[Ni0.8Co0.1Mn0.1]O2 synthesized by sol–gel and co precipitation methods as cathode materials for lithium ion batteries
Solid State Ion.
Defect engineering in oxides by liquid Na K alloy for oxygen evolution reaction
Appl. Surf. Sci.
Improved electrochemical performance of LiNi0.6Co0.2Mn0.2O2 cathode material synthesized by citric acid assisted sol gel method for lithium ion batteries
J. Power Sources
Investigation on electrochemical performance of LiNi0.8Co0.15Al0.05O2 coated by heterogeneous layer of TiO2
J. Alloy. Compd.
Effect of synthesis method on the electrochemical performance of LiNi1/3Mn1/3Co1/3O2
J. Power Sources
Flexible and freestanding heterostructures based on COF derived N doped porous carbon and two dimensional MXene for all solid state lithium sulfur batteries
Chem. Eng. J.
Understanding the underlying mechanism of the enhanced performance of Si doped LiNi0.5Mn0.5−xSixO2 cathode material
Electrochim. Acta
Enhanced electrochemical properties of Ni rich layered cathode materials via Mg2+ and Ti4+ co doping for lithium ion batteries
J. Colloid Interface Sci.
Analysis of the chemical diffusion coefficient of lithium ions in Li3V2(PO4)3 cathode material
Electrochim. Acta
Cited by (1)
High structural stability of graphene coated nickel – rich cathode material in Li – ion battery
2023, Journal of Alloys and Compounds