Tin Alloy-Graphite Composite Anode for Lithium-Ion Batteries

Abstract

A composite anode material was prepared that contains nanosize (<100 nm) particles of tin alloy Sn65Sb18Cu17 and Sn62Sb21Cu17. The alloys were electroplated at high current densities (above iLfalse) from aqueous solutions, directly onto the copper current collector, and were coated by a polyvinylidene fluoride-graphite matrix at a ratio of alloy:graphite matrix 70:30 and 80:20 w/w, respectively. The processes involved in electrode production by this method are inexpensive, simple, and fast. Over 40 (100% depth of discharge) cycles were demonstrated, in half-cell, and over 30 were demonstrated with a LiCoO2 battery containing 1 M LiPF6 ethylene carbonate-diethyl carbonate electrolyte. The faradaic efficiency false(QnormalDe­normalins/QnormalInsfalse) is less than 100%. Lithium is fully deinserted from the host matrix only when the anode is cycled at low current densities. The kinetics of lithium insertion to and deinsertion from the composite anode material, slow gradually as the cycle number increases. X-ray diffraction patterns of the anode material show that the alloy becomes amorphous during cycling, while the graphite does not. X-ray photoelectron-spectroscopy measurements reveal that the solid electrolyte interphase consists of mainly LiF, small amounts of Li2O, and possibly, polymeric substances. The electrochemical behavior of the alloy changes with cycle number, while that of the graphite does not. The fall of the deinsertion capacity of the graphite from the first cycle to the 34th by more than 50% proves that the active material in the anode suffers from particle-to-particle break off. © 2002 The Electrochemical Society. All rights reserved.

Microwave plasma chemical vapor deposition of nano-structured Sn/C composite thin-film anodes for Li-ion batteries

“…Sn, SnO 2 and Sn-based alloy composites with graphite [44,45,46,47], amorphous carbon [48,49] or carbon nanotubes [50] used as a mechanical support and conductive matrix for tin-based active material particles also offer a unique opportunity to combine the stable cyclability of the carbon with the high storage capacity of tin-based materials.…”

“…Fabrication techniques of nano-structured Sn, SnO 2 and carbon/tin composites include autocatalytic deposition [44], ball-milling [41,45,51], chemical reduction [46,50], electrodeposition [47], hydrolysis [48], pyrolysis [49,] sputtering [52], plasma laser deposition (PLD) [53], sol-gel techniques [54], partial reduction [55], precipitation [56], sonochemical methods [57], and vapor deposition [58]. However, these processes often involve several time consuming steps and offer only limited control of the particle size and distribution.…”

Synthesis of PAN/SnCl2 composite as Li-ion battery anode material

“…4) that are derived from the discharge voltage profiles indicate that initial reaction of electrode with Li + ions takes place at 1.35 and 0-0.4 V. The peaks at 0.4-0.7 V are related with the dealloying reaction of Sn in the charge process [23,24]. The peak at 0.3-0 V is related with the alloying reaction of Sn in the flowing discharge process [1,2].…”

Iraq Reconstruction Project Terminations Represent a Range of Actions

“…The need for energy storage devices with higher energy densities, lower weight and volume, and more efficient form factors has driven research into a wide variety of new electrode materials (1)(2)(3)(4). Carbon is a commonly used material for anodes in modern technologies, particularly in lithium-ion batteries and electrochemical supercapacitors.…”

“…Graphitic carbon allows for efficient ion intercalation and is of particular interest for the former (5,6), while carbon with a high surface area optimizes use of the double layer effect and is desirable for the latter (4,7). Considerable effort has been directed towards surpassing graphite's theoretical capacity of 372 mA*h/g using non-carbonaceous materials such as metal oxides and tin alloys (1,3,8).…”