Electroless Copper Metallization for Improving Li-Ion Batteries Performances
In this work, copper coating has been applied on LiCoO2 particles in order to allow the use of water as solvent in the manufacturing process of the cathodes for Li-ion batteries. The deposition was done with autocatalytic technique in a formaldehyde bath, through a two steps process: (i) Pd-activation of the particles and (ii) the growth of the coating on the particles with the reduction of Cu ions. The treatment allowed the deposition of a homogeneous copper layer on the particles. The electrodes manufactured with the coated powders of active material showed an increased electrical conductivity. Electrochemical characterization has been carried out to investigate the nature of the coating, and performances of the obtained cathodes have been evaluated by means of galvanostatic cycling in coin cells after the first 50 cycles at 0.33 C. The presence of copper on the particles of active material has shown its effectiveness under more severe cycling conditions. The coating allows using water as solvent in the preparation of the cathodes, leading to NMP-free manufacturing process of lithium-ion batteries. Electroless copper deposition was used also to coat silicon particles for anode preparation. Both autocatalytic deposition and galvanic displacement in fluoride containing solution have been tested. Silicon particles copper coated are characterized by better performances at the beginning of the cycling test; with cycling, lithiation/delithiation capacity for copper coated electrodes becomes comparable with the one obtained without copper.
With the contribution of the LIFE financial instrument of the European Community - LIFE12 ENV IT 000712 LIFE+ GLEE.
 J. Shu, M. Shui, F. Huang, Y. Ren, Q. Wang, D. Xu, L. Hou, J. Phys. Chem. C 114 (2010) 3323.
 M. S. Whittingham, Chem. Rev. 104 (2004) 4271.
 Y. Gu, D. Chen, X. Jiao J. Phys. Chem. B 109 (2005) 17901.
 M. M. Thackeray, W. I. F. David, P. G. Bruce, J. B. Goodenough, Mater. Res. Bull. 18 (1983) 461.
 A. K. Padhi, K.S. Nanjundaswamy, J.B. Goodenough, J.Electrochem. Soc. 144 (1997) 1188.
 F. T. Quinlan, R. Vidu, L. Predoana, M. Zaharescu, M. Gartrner, J. Groza, P. Stroeve, Ind. Eng. Chem. Res. 43 (2004) 2468.
 C. Li, H.P. Zhang, L.J. Fu, H. Liu, Y.P. Wu, E. Rahm, R. Holze, H.Q. Wu, Elect. Acta 51 (2006) 3872.