Electrochemically enhanced Cu6Sn5 anodes with tailored crystal orientation and ordered atomic arrangements for lithium-ion battery applications

Cobalt‐doped Cu6Sn5 lithium‐ion battery anodes with enhanced electrochemical properties

“…In our experiment, only the Cu 6 Sn 5 ‐hCo sample has a Co composition above this threshold and the consistent substitution of one Co in every two unit cells may have resulted in the additional reflections observed at 30.88°, 32.18°, and 55.48° 2θ as pointed out by the red arrows in Figure 5A. Furthermore, another DFT calculation showed that Li‐ion transports in the η ‐Cu 6 Sn 5 in a zig‐zag pattern along the η [111] channels, [ 13 ] which is equivalent to the η’ [110] channels marked out in green and cyan in Figure 5B. The η’ [110] view shows that the green channels are partially blocked by the Cu’ position.…”

“…The Cu 6 Sn 5 ‐lCo and the Cu 6 Sn 5 ‐mCo electrodes show capacities above the theoretical capacity, which could be due to the apparent capacity contributions from the formation of solid electrolyte interphases (SEIs) and the storage of Li in grain boundaries or defect sites due to the low lithiation current. [ 13 ] It is interesting to note that the apparent capacity is related inversely to the grain size of the electrodes reported in Table 2, which is likely related to the higher surface areas of these electrodes.…”

“…The low CEs which also contributed to the low cycling stability is attributed to the incompatibility of the commercial EC/DMC LiPF 6 electrolyte with Sn-based anodes to form stable SEIs. [13] Further work involving the development of a compatible electrolyte, for example, by a formulation with fluroethylene carbonate (FEC) [30,31] and vinylene carbonate (VC) [31,32] additives are required to improve the cycling stability of the electrodes.…”

“…Extensive studies have shown a reduced likelihood of Li metal plating in Sn-based anodes, [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] making Sn-based anode materials one of the most promising candidates to replace carbon-based anodes. Sn has a higher averaged reaction potential of 0.43 V versus Li/Li + compared to carbon which reacts between 0 and 0.2 V versus Li/Li + , [15] resulting in a lower risk for Li metal plating in Sn-based anodes.…”

Rapid fabrication of tin-copper anodes for lithium-ion battery applications

“…1a). The resultant anode is found to achieve a capacity of up to 929 mAh g -1 at a charge/discharge rate of C/7, and retaining up to 480 mAh g -1 at 2C [5]. However, the growth rate of Cu 6 Sn 5 is slow, where only a few micrometres of Cu 6 Sn 5 is grown in hours, presenting a major hurdle for commercial production using this method.…”