Designing positive electrodes with high energy density for lithium-ion batteries

Abstract

We demonstrate a machine-learning analysis of large-capacity/high-voltage battery cathodes, which quantitatively evaluates the importance of ever-attempted technical solutions.

Synthesis of a High-Capacity α-Fe2O3@C Conversion Anode and a High-Voltage LiNi0.5Mn1.5O4 Spinel Cathode and Their Combination in a Li-Ion Battery

“…250 W h kg –1 for a high number of charge/discharge cycles. 4 , 6 Graphite uptakes Li + delivering a capacity of 372 mA h g –1 , which is limited by the amount of alkali-metal ions stored within the carbon layers, reaching a maximum of 0.16 Li-equivalents per mole of C, that is, according to the LiC 6 chemical formula. 7 , 8 Transition-metal oxides react in the cell by an electrochemical conversion pathway mainly occurring below 1.5 V versus Li + /Li and involving a multiple exchange of electrons, which ensures a higher capacity than that of graphite.…”

“…Electric vehicles (EVs), hybrid-EVs (HEVs), and plug-in HEVs are predominantly powered by the most common version of the lithium-ion battery, that is, the one combining a graphite anode with a layered transition-metal-oxide cathode and employed in common portable electronics. − This system is based on the electrochemical (de)­insertion of lithium into and from the electrode materials and can typically store ca. 250 W h kg –1 for a high number of charge/discharge cycles. , Graphite uptakes Li + delivering a capacity of 372 mA h g –1 , which is limited by the amount of alkali-metal ions stored within the carbon layers, reaching a maximum of 0.16 Li-equivalents per mole of C, that is, according to the LiC 6 chemical formula. , Transition-metal oxides react in the cell by an electrochemical conversion pathway mainly occurring below 1.5 V versus Li + /Li and involving a multiple exchange of electrons, which ensures a higher capacity than that of graphite. − However, this intriguing class of materials intrinsically suffers from poor electrical conductivity and a large volume change throughout the electrochemical process, which causes the voltage hysteresis and rapid cell decay upon cycling . A suitable strategy to mitigate the various issues hindering the efficient use of these alternative anodes is represented by engineering nanostructured oxides with an increased active surface .…”

Machine learning in energy storage materials

“…Reproduced with permission. [109] Copyright 2016, American Chemical Society For LIBs, ML is also contributing to accelerating the screening of novel battery materials, [114][115][116][117] such as active electrodes and solid/liquid electrolyte materials as illustrated in Figure 1C. For example, in the case of solid electrolytes, massive efforts are focused on the search for inorganic/polymer solid ion conductors with high ionic conductivities and suitable mechanical properties.…”

Square-Scheme Electrochemistry in Battery Electrodes

“…Furthermore, the assumption of homogeneous chemical reactions O → O′ or R → R′ in a square scheme may oversimplify the heterogeneous structural changes occurring within electrodes. However, even for such complicated electrodes, an appropriate physical model and discriminating data analysis should enable a quantitative estimation of the underlying link between energetics and kinetics …”