There is great interest in developing rechargeable lithium batteries with higher energy capacity and longer cycle life for applications in portable electronic devices, electric vehicles and implantable medical devices. Silicon is an attractive anode material for lithium batteries because it has a low discharge potential and the highest known theoretical charge capacity (4,200 mAh g(-1); ref. 2). Although this is more than ten times higher than existing graphite anodes and much larger than various nitride and oxide materials, silicon anodes have limited applications because silicon's volume changes by 400% upon insertion and extraction of lithium which results in pulverization and capacity fading. Here, we show that silicon nanowire battery electrodes circumvent these issues as they can accommodate large strain without pulverization, provide good electronic contact and conduction, and display short lithium insertion distances. We achieved the theoretical charge capacity for silicon anodes and maintained a discharge capacity close to 75% of this maximum, with little fading during cycling.

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High-performance lithium battery anodes using silicon nanowires

[Liu, Chang; Li, Feng; Ma, Lai-Peng; Cheng, Hui-Ming] Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China.;Cheng, HM (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, 72 Wenhua Rd, Shenyang 110016, Peoples R China;cheng@imr.ac.cn

Advanced Materials for Energy Storage

Rechargeable lithium-sulfur batteries.

Si-based Li-ion battery anodes have recently received great attention, as they offer specific capacity an order of magnitude beyond that of conventional graphite. The applications of this transformative technology require synthesis routes capable of producing safe and easy-to-handle anode particles with low volume changes and stable performance during battery operation. Herein, we report a large-scale hierarchical bottom-up assembly route for the formation of Si on the nanoscale--containing rigid and robust spheres with irregular channels for rapid access of Li ions into the particle bulk. Large Si volume changes on Li insertion and extraction are accommodated by the particle's internal porosity. Reversible capacities over five times higher than that of the state-of-the-art anodes (1,950 mA h g(-1)) and stable performance are attained. The synthesis process is simple, low-cost, safe and broadly applicable, providing new avenues for the rational engineering of electrode materials with enhanced conductivity and power.

High-performance lithium-ion anodes using a hierarchical bottom-up approach

A review of the electrochemical performance of alloy anodes for lithium-ion batteries

A method is described in which crystalline silicon can be used as a practical anode material for lithium-ion batteries. Commercial lithium-ion cells are typically charged at a constant current to a fixed voltage and then are held by the charger at constant voltage until the current decreases to a certain value (also known as constant current/constant voltage or CCCV charging). It is first shown that CCCV charging can be used to reversibly cycle crystalline silicon and limit its capacity. A cycling method is then demonstrated in which crystalline silicon is first partially converted to amorphous silicon, in situ, during conditioning cycles. After the conditioning cycles the silicon can be cycled normally, using CCCV cycling limits, with good coulombic efficiency and little overlithiation during the first cycle.

Reversible Cycling of Crystalline Silicon Powder

The Electrochemical Behavior of Polyimide Binders in Li and Na Cells

The silicon as an anode material for use in lithium ion batteries according to the present invention provides a method for cell manufacturing. The degree to which the silicon is lithiated during cycling can be controlled, thereby lowering the volume expansion while maintaining an acceptable volumetric capacity, and reducing the failure rate of the silicon containing anodes in lithium ion batteries. The crystalline silicon anode is first charged so that the anode becomes partially lithiated. The voltage of the anode during this charging step is typically less than the lithiation potential of crystalline silicon at ambient temperatures, for example, less than 17OmV versus lithium metal. The total number of charge-discharge cycles during conditioning is at least two or more.

Method of using an electrochemical cell

Isothermal Calorimetry Evaluation of Metallurgical Silicon as a Negative Electrode Material for Li-Ion Batteries

https://iopscience.iop.org/article/10.1149/2.0351813jes/pdf

L. J. Krause

Papers

Reversible Cycling of Crystalline Silicon Powder

The Electrochemical Behavior of Polyimide Binders in Li and Na Cells

Method of using an electrochemical cell

Isothermal Calorimetry Evaluation of Metallurgical Silicon as a Negative Electrode Material for Li-Ion Batteries

Design of Positive Electrodes for Li-Ion Full Cells with Silicon