Walnut Inspired Silicon Carbon Composites for Stable Lithium Ions Battery Anodes
Xuli Ding,
Daowei Liang,
Yi Liu
Issue:
Volume 4, Issue 1, June 2020
Pages:
1-7
Received:
29 November 2019
Accepted:
21 December 2019
Published:
6 January 2020
DOI:
10.11648/j.cm.20200401.11
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Abstract: The distinct quality of silicon (Si) makes it a natural choice for employment as a competitive anode material in rechargeable high specific energy lithium-ion batteries (LIBs) for practical applications. However, the Si-based LIBs are still hindered for practical applications due to the weak electrical conductivity and unstable solid electrolyte interfaces (SEI). New structures with enhanced conduction are highly desired to push the advance of Si-based LIBs. Herein, the Si nanoparticles coated by few-layer graphene (fGra) has been wrapped into honeycomb porous carbon (Pc) framework with good Si-C contact and reliable void via a simple chemical vapor deposition accompanying with freeze drying strategy. The walnut-type structure noted as Si@Gra@Pc is obtained, in which the porous architecture not only shorten the transfer distance of the lithium ions but also provide good electrical conductivity for the charge carriers. Moreover, the porous structure permit the free expansion of Si during charging/discharging cycling and preserve the integrity of the electrode owing to the brawny mechanical strength of Gra and Pc framework. Importantly, it is found that the Si@Gra@Pc composites show good rate capability reached to 5Ag-1 with specific capacity of 450 mAh g-1 and good cycling stability with no distinct capacity decay even after 1000 cycles, which are obvious improving compared with that of the bare Si anodes. Combined with the simple and feasible fabrication method and improved electrochemical performance for the Si anodes in LIBs. The present walnut-type Si@Gra@Pc composite is considered as the promising and meaningful Si-based anode materials and candidates in the development of next-generation high specific energy LIBs.
Abstract: The distinct quality of silicon (Si) makes it a natural choice for employment as a competitive anode material in rechargeable high specific energy lithium-ion batteries (LIBs) for practical applications. However, the Si-based LIBs are still hindered for practical applications due to the weak electrical conductivity and unstable solid electrolyte in...
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A Review on Brake Pad Materials and Methods of Production
Danladi Ozokwere Ayogwu,
Ibrahim Saidu Sintali,
Mohammed Ahmed Bawa
Issue:
Volume 4, Issue 1, June 2020
Pages:
8-14
Received:
23 May 2020
Accepted:
9 June 2020
Published:
20 June 2020
DOI:
10.11648/j.cm.20200401.12
Downloads:
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Abstract: Brake pads most especially in the automotive industry play a vital role in controlling the speed of a moving vehicle or machines in some instances. This can only be achieved through careful formulations of selected materials in the right proportions. However, not all brake pads materials are safe for use in automobile and other industrial applications, due to environmental pollution and other health related factors. Thus, the need to develop materials which are considerably suitable and at the same time energy efficient in nature becomes necessary in order to minimize and reduce further damage to an already damaged environment. Thus, environment friendly and non-toxic materials are gaining popularity, and hence, a priority among researchers and industries. The heralding introduction of environmentally friendly natural fibres to replace asbestos in a control composition with other additives in the production of brake pads proves to be a popularly embraced concept among recent researchers. This paper presents review on mechanical properties, tribological behavior, water absorption capacity, dynamic mechanical analysis, morphological and thermal properties of organic reinforced brake pad composites with respect to the materials used and methods of production employed. Findings of this study show that hybridization, modification, chemical treatment and composition control of constituent materials can improve mechanical, thermal and dynamic mechanical properties as well as reduce wear rate and water absorption property. It can be concluded that many researchers were able to improve the performance of braking systems by introducing environmental and user friendly composite materials that can withstand the test of time.
Abstract: Brake pads most especially in the automotive industry play a vital role in controlling the speed of a moving vehicle or machines in some instances. This can only be achieved through careful formulations of selected materials in the right proportions. However, not all brake pads materials are safe for use in automobile and other industrial applicati...
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