Effect of Phosphorus Doping into the Silicon as an Anode Material for Lithium Secondary Batteries

Kong, Myung Ho; Byun, Dong Jin; Lee, Joong Kee

doi:10.4028/www.scientific.net/amr.26-28.333

Cited by 3 publications

(1 citation statement)

References 5 publications

(5 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…First principles computational studies have been carried out on bulk crystalline Si showing that interstitial sites are the most favorable for single Li insertion into the crystalline Si lattice . While a few studies exist on the lithiation of doped Si, these involved amorphous Si or polycrystalline Si-graphite mixtures, , in which the effects of dopants apart from electrical conductivity enhancement may be obscured. Dopants have been shown to change the properties of Si in processes such as electrochemical etching .…”

Section: Introductionmentioning

confidence: 99%

Dopant Modulated Li Insertion in Si for Battery Anodes: Theory and Experiment

et al. 2011

View full text Add to dashboard Cite

Lithium-ion batteries are energy storage devices for portable electronics and are also of interest for more demanding applications, such as transportation. Present day Li-ion batteries feature a transition metal oxide cathode such as LiCoO 2 , LiMn 2 O 4 , or LiFePO 4 and a graphitic carbon anode. 1,2 These anode and cathode materials have Li capacities that are much less than desired. On the anode side, the graphitic anode presently utilized exhibits a low theoretical specific capacity of 372 mAhg À1 . 3 Other anode materials have much greater capacities. 4 Among these, Si is of intense interest due to its 4200 mAhg À1 theoretical specific capacity in its fully lithiated composition, over an order of magnitude greater than graphitic carbon. 5 Currently the extreme volumetric expansion of Si during lithiation limits its practical use owing to the large mechanical strain encountered, which leads to pulverization and loss of active material. 6 Several different methods have been researched to improve the cyclability of silicon, such as limiting the voltage range, 7 making thin film electrodes, 8À11 alloying, 12À15 and creating composites with carbon. 16À20 Limthongkul et al. first reported that crystalline Si undergoes solid-state amorphization upon reaction with Li. 21 Obrovac and Christensen confirmed this amorphization and showed via ex situ XRD that the Li 15 Si 4 phase crystallizes below 50 mV. 22 Raman spectroscopy showed the transition from crystalline to amorphous Si in a carbon composite by monitoring the 520 cm À1 c-Si phonon mode. 23 Recently we used Raman spectroscopy to show that Li inserts anisotropically into single crystalline Si. 24 Work to date on the lithium insertion into, and accompanying amorphization of, crystalline Si has primarily dealt with undoped Si. First principles computational studies have been carried out on bulk crystalline Si showing that interstitial sites are the most favorable for single Li insertion into the crystalline Si lattice. 25 While a few studies exist on the lithiation of doped Si, these involved amorphous Si 26 or polycrystalline Si-graphite mixtures, 27,28 in which the effects of dopants apart from electrical conductivity enhancement may be obscured. Dopants have been shown to change the properties of Si in processes such as electrochemical etching. 29 A first principles study suggests that dopants can have an effect on the binding energy of Li with Si. 30 First principle studies on Si nanowires show nontrivial effects of surface passivating species such as H and halogens on Li binding energies. 31 However, the fundamental effects of dopants on Li insertion into crystalline Si remain unclear, particularly with regard to anisotropy and energetics. The work in this paper is aimed at developing a better fundamental understanding of the role of dopants on the lithiation of crystalline silicon electrodes. We present in situ Raman spectroscopy experiments and density functional theory (DFT) calculations of the effects of dopants on the lithiation of Si. We show that addit...

show abstract

Section: Introductionmentioning

confidence: 99%

Dopant Modulated Li Insertion in Si for Battery Anodes: Theory and Experiment

et al. 2011

View full text Add to dashboard Cite

show abstract

3D network-structured CoSb/P-CNFs@rGO as a highly conductive self-supporting anode material for lithium-ion batteries

Wei

Xie

et al. 2023

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Ultrafast Electrochemical Lithiation of Individual Si Nanowire Anodes

et al. 2011

View full text Add to dashboard Cite

Using advanced in situ transmission electron microscopy, we show that the addition of a carbon coating combined with heavy doping leads to record-high charging rates in silicon nanowires. The carbon coating and phosphorus doping each resulted in a 2 to 3 orders of magnitude increase in electrical conductivity of the nanowires that, in turn, resulted in a 1 order of magnitude increase in charging rate. In addition, electrochemical solid-state amorphization (ESA) and inverse ESA were directly observed and characterized during a two-step phase transformation process during lithiation: crystalline silicon (Si) transforming to amorphous lithium-silicon (Li(x)Si) which transforms to crystalline Li(15)Si(4) (capacity 3579 mAh·g(-1)). The ultrafast charging rate is attributed to the nanoscale diffusion length and the improved electron and ion transport. These results provide important insight in how to use Si as a high energy density and high power density anode in lithium ion batteries for electrical vehicle and other electronic power source applications.

show abstract

Effect of Phosphorus Doping into the Silicon as an Anode Material for Lithium Secondary Batteries

Cited by 3 publications

References 5 publications

Dopant Modulated Li Insertion in Si for Battery Anodes: Theory and Experiment

Dopant Modulated Li Insertion in Si for Battery Anodes: Theory and Experiment

3D network-structured CoSb/P-CNFs@rGO as a highly conductive self-supporting anode material for lithium-ion batteries

Ultrafast Electrochemical Lithiation of Individual Si Nanowire Anodes

Contact Info

Product

Resources

About