scholarly journals A Fast and Scalable Pre-Lithiation Approach for Practical Large-Capacity Lithium-Ion Capacitors

2021 ◽  
Author(s):  
Xianzhong Sun ◽  
Penglei Wang ◽  
Yabin An ◽  
Xiong Zhang ◽  
Shuanghao Zheng ◽  
...  
Keyword(s):  
Electrode Materials ◽  
Short Circuit ◽  
Rate Capability ◽  
Lithium Ion ◽  
Internal Resistance ◽  
Open Circuit ◽  
High Rate ◽  
Potential Cycling ◽  
Large Capacity ◽  
Voltage Loss

Abstract Lithium-ion capacitors (LICs) bridge the gap between lithium-ion batteries (LIBs) and electrical double-layer capacitors (EDLCs) owing to their unique energy storage mechanisms. From the viewpoints of electrode materials and cell design, the pre-lithiation process is indispensable for improving the working voltage and energy density of LICs. However, the conventional physical short-circuit (PSC) method is time-consuming, which limits the mass-production of practical large-capacity LIC cells. Three alternative pre-lithiation protocols have been proposed, combining the PSC protocol and electrochemical approaches to shorten the pre-lithiation time. The prototype LIC pre-lithiated by using the open-circuit potential cycling (OPC) protocol has the lowest internal resistance and superior high-rate capability (even at 200C-rate). The 900-F large-capacity laminated LIC cells have been assembled and pre-lithiated to validate the feasibility of this method. The pre-lithiation time has been reduced from 470 h (PSC protocol) to 19 h (OPC protocol). This combined protocol is presumed to counteract the voltage loss and enhance the Li+ ion diffusion between multiple anode electrodes during the pre-lithiation process.

scholarly journals Achieving of High Density/Utilization of Active Groups via Synergic Integration of C=N and C=O Bonds for Ultra-Stable and High-Rate Lithium-Ion Batteries

Research ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Tao Sun ◽  
Zong-Jun Li ◽  
Xin-Bo Zhang
Keyword(s):  
Electrode Materials ◽  
High Current Density ◽  
Low Cost ◽  
Rate Capability ◽  
Lithium Ion ◽  
High Rate ◽  
Electrochemical Performances ◽  
Environmental Friendliness ◽  
Practical Applications ◽  
Organic Electrode

Organic electrode materials are receiving ever-increasing research interest due to their combined advantages, including resource renewability, low cost, and environmental friendliness. However, their practical applications are still terribly plagued by low conductivity, poor rate capability, solubility in electrolyte, and low density/utilization of active groups. In response, herein, as a proof-of-concept experiment, C=N and C=O bonds are synergically integrated into the backbone of pentacene to finely tune the electronic structures of pentacene. Unexpectedly, the firstly obtained unique 5,7,11,14-tetraaza-6,13-pentacenequinone/reduced graphene oxide (TAPQ/RGO) composite exhibits superior electrochemical performances, including an ultra-stable cycling stability (up to 2400 cycles) and good rate capability (174 mAh g−1 even at a high current density of 3.2 A g−1), which might be attributed to the abundant active groups, π-conjugated molecular structure, leaf-like morphology, and the interaction between TAPQ and graphene.

Controllable preparation of Fe-containing Li-rich cathode material Li[Li1/5Fe1/10Ni3/20Mn11/20]O2 with stable high-rate properties for Li-ion batteries

2021 ◽  
pp. 2150004
Author(s):  
Taolin Zhao ◽  
Liyao Chang ◽  
Rixin Ji
Keyword(s):  
Calcination Temperature ◽  
Electrode Materials ◽  
Specific Capacity ◽  
Great Influence ◽  
Rate Capability ◽  
Lithium Ion ◽  
High Rate ◽  
Precipitation Method ◽  
High Rate Capability ◽  
Charge Discharge

Generally, the optimization of synthesis conditions has great influence on the properties of the electrode materials for lithium-ion batteries (LIBs). Nowadays, Li-rich manganese-based cathode materials with high capacity are still suffering from low first charge/discharge capacity and poor high-rate capability. In this work, Li[Li[Formula: see text]Fe[Formula: see text]Ni[Formula: see text]Mn[Formula: see text]]O2 has been successfully synthesized by hydroxide co-precipitation method, and the effect of calcination temperature on the material characteristics and electrochemical performance has been investigated. The results show that with the increase of calcination temperature, the layered structure of Li-rich material becomes better. When the calcination temperature is 800[Formula: see text]C, the prepared material exhibits the most excellent electrochemical properties, including high first charge/discharge specific capacity of 366.6/251.9 mAh g[Formula: see text] and good high-rate capability. It is expected that the results of this study can lay a solid foundation for the subsequent research on the modification of this material.

Highly ordered nanoscale phosphomolybdate-grafted polyaniline/metal hybrid layered structures prepared via secondary sputtering phenomenon as high-performance pseudocapacitor electrodes

2021 ◽  
Author(s):  
Eun Seop Yoon ◽  
Bong Gill Choi ◽  
Hwan-Jin Jeon
Keyword(s):  
Electron Transfer ◽  
Aspect Ratio ◽  
Electrochemical Performance ◽  
High Aspect Ratio ◽  
High Performance ◽  
Electrode Materials ◽  
Rate Capability ◽  
High Specific Capacitance ◽  
High Rate ◽  
Large Area

Abstract The development of energy storage electrode materials is important for enhancing the electrochemical performance of supercapacitors. Despite extensive research on improving electrochemical performance with polymer-based materials, electrode materials with micro/nanostructures are needed for fast and efficient ion and electron transfer. In this work, highly ordered phosphomolybdate (PMoO)-grafted polyaniline (PMoO-PAI) deposited onto Au hole-cylinder nanopillar arrays is developed for high-performance pseudocapacitors. The three-dimensional nanostructured arrays are easily fabricated by secondary sputtering lithography, which has recently gained attention and features a high resolution of 10 nm, a high aspect ratio greater than 20, excellent uniformity/accuracy/precision, and compatibility with large area substrates. These 10nm scale Au nanostructures with a high aspect ratio of ~30 on Au substrates facilitate efficient ion and electron transfer. The resultant PMoO-PAI electrode exhibits outstanding electrochemical performance, including a high specific capacitance of 114 mF/cm2, a high-rate capability of 88%, and excellent long-term stability.

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