Immersion-plated Cu6Sn5/Sn composite film anode for lithium ion battery

Herein, a simple one-step immersion plating method is firstly used to prepare Cu6Sn5/Sn composite film electrode for lithium ion battery and thiourea (TU) is used as potential adjustment agent in the deposition process. The films with different morphologies are obtained by changing the content of tin(II) chloride (SnCl2). After a series of physical and electrochemical characterizations, the results demonstrate that the content of SnCl2 in the plating solution plays an important role in determining the morphology and component of film electrode. In the condition of SnCl2 6.5 g L−1, film electrode obtains both void space to accommodate volume expansion and stable structure which could inhibit abscission of active material from current collector. Therefore, the film electrode has an excellent areal capacity of 0.84 mA h cm−2 after 70 cycles. In comparison with reported Sn–Cu alloy planar film electrodes for lithium ion battery in recent decade, the film electrode in this work exhibits a higher areal capacity.