The increasing interest in energy storage for the grid can be attributed to multiple factors, including the capital costs of managing peak demands, the investments needed for grid reliability, and the integration of renewable energy sources. Although existing energy storage is dominated by pumped hydroelectric, there is the recognition that battery systems can offer a number of high-value opportunities, provided that lower costs can be obtained. The battery systems reviewed here include sodium-sulfur batteries that are commercially available for grid applications, redox-flow batteries that offer low cost, and lithium-ion batteries whose development for commercial electronics and electric vehicles is being applied to grid storage.

Electrical Energy Storage for the Grid: A Battery of Choices

2.1. Solvents 4307 2.1.1. Propylene Carbonate (PC) 4308 2.1.2. Ethers 4308 2.1.3. Ethylene Carbonate (EC) 4309 2.1.4. Linear Dialkyl Carbonates 4310 2.2. Lithium Salts 4310 2.2.1. Lithium Perchlorate (LiClO4) 4311 2.2.2. Lithium Hexafluoroarsenate (LiAsF6) 4312 2.2.3. Lithium Tetrafluoroborate (LiBF4) 4312 2.2.4. Lithium Trifluoromethanesulfonate (LiTf) 4312 2.2.5. Lithium Bis(trifluoromethanesulfonyl)imide (LiIm) and Its Derivatives 4313

/pdf/nonaqueous-liquid-electrolytes-for-lithium-based-uxm5ffbi18.pdf

Nonaqueous liquid electrolytes for lithium-based rechargeable batteries.

Research Development on Sodium-Ion Batteries

Rechargeable lithium-sulfur batteries.

Metal Oxides and Oxysalts as Anode Materials for Li Ion Batteries

The structural changes in silicon electrochemically lithiated and delithiated at room temperature were studied by X-ray powder diffraction. Crystalline silicon becomes amorphous during lithium insertion, confirming previous studies. Highly lithiated amorphous silicon suddenly crystallizes at 50 mV to form a new lithium-silicon phase, identified as This phase is the fully lithiated phase for silicon at room temperature, not as is widely believed. Delithiation of the phase results in the formation of amorphous silicon. Cycling silicon anodes above 50 mV avoids the formation of crystallized phases completely and results in better cycling performance. © 2004 The Electrochemical Society. All rights reserved.

https://iopscience.iop.org/article/10.1149/1.1652421/pdf

Structural changes in silicon anodes during lithium insertion/extraction

A set of guidelines is proposed for designing high-energy-density alloy anode materials It is first shown that the molar volume of lithium is about 9 mL/mol in a wide variety of lithium alloys and is independent of lithium content Using this property of lithium alloys, simple relationships between the volumetric energy density and the volumetric expansion of an alloy are derived These relationships are extremely powerful for designing alloys with the maximum possible energy density for a given electrode-coating performance

https://iopscience.iop.org/article/10.1149/1.2752985/pdf

Alloy Design for Lithium-Ion Battery Anodes

Si12x Snx samples for 0 , x , 0.5 were prepared by magnetron sputtering using a combinatorial materials science approach. The room-temperature resistivity and X-ray diffraction ~XRD! patterns of the samples were used to select materials having both an amorphous structure and good conductivity for further study. The reaction of lithium with amorphous Si0.66Sn0.34 was then studied by electrochemical methods and by in situ XRD. The electrode material apparently remains amorphous throughout all portions of the charge and discharge profile, in the range 0 , x , 4.4 in LixSi0.66Sn0.34 . No crystalline phases are formed, unlike the situation when lithium reacts with tin. Using the Debye scattering formalism, we show that the XRD patterns of the a-Si0.66Sn0.34 starting material and a-Li4.4Si0.66Sn0.34 can be explained by the same local atomic arrangements as found in crystalline Si and Li4.4 Si or Li4.4 Sn, respectively. In fact, the in situ XRD patterns of a-LixSi0.66Sn0.34 , for any x, can be well approximated by a linear combination of the patterns for x 5 0 and x 5 4.4. This suggests that predominantly only two local environments for Si and Sn are found at any value of x in a-LixSi0.66Sn0.44 . However, based on differential capacity vs. potential results for Li/a-Si 0.66Sn0.34 there is no evidence for two-phase regions during the charge and discharge profile. Thus, the two local environments must appear at random throughout the particles. We speculate that the charge-discharge hysteresis in the voltage-capacity profile of Li/ a-LixSi0.66Sn0.34 cells is caused by the energy dissipated during the changes in the local atomic environment around the host atoms.

/pdf/the-electrochemical-reaction-of-li-with-amorphous-si-sn-2nol9ienmn.pdf

The Electrochemical Reaction of Li with Amorphous Si-Sn Alloys

Large-volume-change electrodes for Li-ion batteries of amorphous alloy particles held by elastomeric tethers

The electrochemical performance of Si electrodes using polyvinylidene fluoride binder heated at different temperatures ranging from 150 to 350°C was investigated. Compared to unheated electrodes that have no capacity after the first formation cycle, the heat-treated electrodes show an increasingly improved cycling performance as the heating temperature increases from 150 to 300°C. In particular, Si electrodes heated at 300°C retain a specific capacity of ∼600 mAh/g for 50 cycles with a lower cutoff potential of 0.170 V vs Li/Li + . The reasons for such improvements are considered based on results from thermal analysis, optical microscopy, and adhesion tests. It is suggested that heat-treatment improves the binder distribution, the adhesion to the Si particles and to the substrate, thereby leading to a better cycling performance.

/pdf/effect-of-heat-treatment-on-si-electrodes-using-4lji40k59t.pdf

Leif Christensen

Papers

Structural changes in silicon anodes during lithium insertion/extraction

Alloy Design for Lithium-Ion Battery Anodes

The Electrochemical Reaction of Li with Amorphous Si-Sn Alloys

Large-volume-change electrodes for Li-ion batteries of amorphous alloy particles held by elastomeric tethers

Effect of Heat Treatment on Si Electrodes Using Polyvinylidene Fluoride Binder