The following example electrolyte compositions may be beneficial for use in Li and Li-ion cells with high capacity nanocomposite electrode particles or powders (e.g., comprising conversion- or alloying-type active anode materials) that experience certain volume changes during cycling (moderately high volume changes (e.g., an increase by about 8-about 160 or about 180 vol. % or a reduction by about 8-about 70 vol. %) during the first charge-discharge cycle and moderate volume changes (e.g., about 4-about 50 vol. %) during the subsequent charge-discharge cycles), an average size in the range from around 0.2 to around 40 microns (for some applications, more preferably from around 0.4 to around 20 microns) and specific surface area in the range from about 0.5 m²/g to about 50 m²/g. These electrolytes may comprise one or more of the following components: (a) low-melting point (LMP) solvent or solvent mixture; (b) regular melting point (RMP) solvent or solvent mixture; (c) additive (ADD) solvent or solvent mixture (added, for example, to improve anode electrolyte interphase properties or to improve cathode electrolyte interphase properties or to stabilize Li salts or to provide other useful functionality); (d) main (MN) Li salt or Li salt mixture; (e) additive (ADD) salt or salt mixture (not necessarily Li-based) (added, for example, to improve anode electrolyte interphase properties or to improve cathode electrolyte interphase properties or to stabilize Li salts or to provide other useful functionality); (f) other functional additives (OFADD) (added, for example, to enhance cell safety), where LMP solvent or LMP solvent mixture may preferably contribute to about 10-about 95 vol. % of the volume of all solvents in the electrolyte (more preferably, the LMP solvent or LMP solvent mixture may contribute to about 10-about 80 vol. % of the volume of all solvents in the electrolyte in some designs; e.g., for cells with high-capacity nanostructured anodes, a more favorable volume fraction of LMP solvents may range from about 20 vol. % to about 60 vol. %); where RMP solvent or RMP solvent mixture may preferably contribute to about 5-about 90 vol. % of the volume of all solvents in the electrolyte (more preferably, the RMP solvent or RMP solvent mixture may contribute to about 20-about 90 vol. % of the volume of all solvents in the electrolyte in some designs); and where ADD solvent or solvent mixture may preferably contribute to about 0-about 6 vol. % of the volume of all solvents in the electrolyte. Particular values of the optimum volume fractions of the LMP, RMP and ADD solvents or solvent mixtures for particular applications may depend on the cell operating potentials, cell operating (or cell storage) temperature and rates of charge and discharge desirable for cells in a given application. Examples of suitable esters for use as LMP solvent(s) or co-solvent(s) may include, but are not limited to, various formates (e.g., methyl formate, ethyl formate, propyl formate, butyl formate, amyl formate, hexyl formate, heptyl formate, etc.), various acetates (e.g., methyl acetate, ethyl acetate, propyl acetate, butyl acetate, amyl acetate, hexyl acetate, heptyl acetate, etc.), various propionates (e.g., methyl propionate, ethyl propionate, propyl propionate, butyl propionate, amyl propionate, hexyl propionate, heptyl propionate, etc.), various butyrates (e.g., methyl butyrate, ethyl butyrate, propyl butyrate, butyl butyrate, amyl butyrate, hexyl butyrate, heptyl butyrate, etc.), various valerates (e.g., methyl valerate, ethyl valerate, propyl valerate, butyl valerate, amyl valerate, hexyl valerate, heptyl valerate, etc.), various caproates (e.g., methyl caproate, ethyl caproate, propyl caproate, butyl caproate, amyl caproate, hexyl caproate, heptyl caproate, etc.), various heptanoates (e.g., methyl heptanoate, ethyl heptanoate, propyl heptanoate, butyl heptanoate, amyl heptanoate, hexyl heptanoate, heptyl heptanoate, etc.), various caprylates (e.g., methyl caprylate, ethyl caprylate, propyl caprylate, butyl caprylate, amyl caprylate, hexyl caprylate, heptyl caprylate, etc.), various nonaoates (e.g., methyl nonaoate, ethyl nonaoate, propyl nonaoate, butyl nonaoate, amyl nonaoate, hexyl nonaoate, heptyl nonaoate, etc.), various decanoates (e.g., e.g., methyl decanoate, ethyl decanoate, propyl decanoate, butyl decanoate, amyl decanoate, hexyl decanoate, heptyl decanoate, etc.), and fluorinated versions of the above-discussed esters, to name a few examples. Examples of solvents suitable for use as RMP solvents in the electrolyte (or for the fabrication of RMP solvent mixtures in the electrolyte) may comprise: various carbonates (fluorinated acyclic carbonates and propylene carbonate may be particularly advantageous for use in cells with high voltage cathodes), various sulfones (e.g., dimethyl sulfone, ethylmethyl sulfone, etc.) and various sulfoxides, various lactones, various phosphorous based solvents (e.g., dimethyl methylphosphonate, triphenyl phosphate, etc.), various silicon based solvents, various types of higher melting point esters (e.g., esters with melting points above around minus (?) 50° C.), various ethers (e.g., dioxolane, monoglyme, diglyme, triglyme, tetraglyme, and polyethylene oxide, etc.), various cyclic ester-based molecules (e.g., butyrolactones and valerolactones), various dinitriles (e.g., succinonitrile, adiponitrile, and glutaronitrile), and various ionic liquids (e.g., imidazoliums, pyrrolidiniums, piperidiniums, etc., may be particularly useful in cells comprising high voltage cathodes). RMP solvent(s) may also be (either fully or partially) fluorinated.