Synthesis and Electrochemical Behavior of Nanostructured Copper Particles on Graphite for Application in Lithium Ion Batteries

Abstract

Graphitic materials are currently the state-of-the-art anode materials for lithium ion secondary batteries. By chemical modification, the electrochemical performance of the pristine materials can be improved. In this paper we report on the preparation of nanostructured copper particles on graphite by thermal decomposition of copper formate. With this technique a novel, simple and low cost method for a homogeneous deposition of nanostructured copper particles on graphite was established. Different amounts of copper were realized and their influence on the electrochemical behavior of the active material was investigated. The copper particles had a size distribution between 50 nm and 300 nm. Electrochemical measurements displayed an improved performance of the synthesized composite material compared to the pristine material. Cyclic voltammetry showed a suppressed cointercalation of solvated lithium and an increased formation of the solid electrolyte interphase (SEI). Battery cycling demonstrated an increased discharge capacity and cycling stability.

Silicon-Core–Carbon-Shell Nanoparticles for Lithium-Ion Batteries: Rational Comparison between Amorphous and Graphitic Carbon Coatings

“…The CV curve of graphite displays only one visible redox peak in lithiation, around 0.12 V vs Li + /Li, and one in delithiation, around 0.3−0.35 V versus Li + /Li (broken arrows in Figure 5c). 26,27 The silicon nanomaterials show one redox peak in lithiation, around 0.2 V vs Li + /Li, and two in delithiation, around 0.38 V versus Li + /Li and 0.5 V versus Li + / Li (solid arrows in Figure 5d and Figure s9a). Finally, the CV of the blended electrode comprises a convolution of both the contribution of graphite and silicon (see Figure 5e and Figure s9b-c), as both silicon and graphite contribute to the lithiation/delithiation process in the electrode material.…”

Improved Electrochemical Performance of Modified Mesocarbon Microbeads for Lithium‐Ion Batteries Studied using Solid‐State Nuclear Magnetic Resonance Spectroscopy

“…The current density of the corresponding peak pair of MCMB_Cu is two times higher, which indicates more‐efficient intercalation behavior and a therefore higher capacity. The corresponding irreversible cathodic peak at approximately 0.6 V, which is reported to be characteristic for solvent co‐intercalation does not appear in the CV of MCMB. This corresponds well to the fact that the thickness of MCMB particles is increased compared to flake graphite.…”

“…Licht et al. investigated the influence of the copper content on the electrochemical behavior of MCMB and found an optimum at this value . Cyclic voltammetry measurements were performed to identify different electrochemical reactions.…”

“…The modification of MCMB with copper depositions was prepared as reported by Licht et al. 2015 . MCMB was mixed with copper formate [Cu(HCOO) 2 ⋅4 H 2 O, Alfa Aesar, 98 %] using a Retsch mixer mill MM 200, at a low frequency of 20 Hz for 1 h. The powder blend then was transferred into a reaction tube, heated for 30 min to 100 °C, and then heated for 1 h at 300 °C under argon flow.…”

“…It is also possible that nanostructured metals have a catalytic effect on the lithium intercalation. Licht et al . demonstrated the suppression of the co‐intercalation of solvated lithium ions using flake graphite modified with copper.…”