摘要:
Novel chain polymers comprising weakly basic anionic moieties chemically bound into a polyether backbone at controllable anionic separations are presented. Preferred polymers comprise orthoborate anions capped with dibasic acid residues, preferably oxalato or malonato acid residues. The conductivity of these polymers is found to be high relative to that of most conventional salt-in-polymer electrolytes. The conductivity at high temperatures and wide electrochemical window make these materials especially suitable as electrolytes for rechargeable lithium batteries.
摘要:
Novel conductive polyanionic polymers and methods for their preparion are provided. The polyanionic polymers comprise repeating units of weakly-coordinating anionic groups chemically linked to polymer chains. The polymer chains in turn comprise repeating spacer groups. Spacer groups can be chosen to be of length and structure to impart desired electrochemical and physical properties to the polymers. Preferred embodiments are prepared from precursor polymers comprising the Lewis acid borate tri-coordinated to a selected ligand and repeating spacer groups to form repeating polymer chain units. These precursor polymers are reacted with a chosen Lewis base to form a polyanionic polymer comprising weakly coordinating anionic groups spaced at chosen intervals along the polymer chain. The polyanionic polymers exhibit high conductivity and physical properties which make them suitable as solid polymeric electrolytes in lithium batteries, especially secondary lithium batteries.
摘要:
Methods for making composite anodes, such as macroporous composite anodes, are disclosed. Embodiments of the methods may include forming a tape from a slurry including a substrate metal precursor, an anode active material, a pore-forming agent, a binder, and a solvent. A laminated structure may be prepared from the tape and sintered to produce a porous structure, such as a macroporous structure. The macroporous structure may be heated to reduce a substrate metal precursor and/or anode active material. Macroporous composite anodes formed by some embodiments of the disclosed methods comprise a porous metal and an anode active material, wherein the anode active material is both externally and internally incorporated throughout and on the surface of the macroporous structure.
摘要:
Electrodeposition involving an electrolyte having a surface-smoothing additive can result in self-healing, instead of self-amplification, of initial protuberant tips that give rise to roughness and/or dendrite formation on the substrate and/or film surface. For electrodeposition of a first conductive material (C1) on a substrate from one or more reactants in an electrolyte solution, the electrolyte solution is characterized by a surface-smoothing additive containing cations of a second conductive material (C2), wherein cations of C2 have an effective electrochemical reduction potential in the solution lower than that of the reactants.
摘要:
A method for making a lithium battery or lithium ion battery having nitrogen silylated compounds as additives in a nonaqueous electrolytic solution. Batteries using this electrolytic solution have long cycle life and high capacity retention.
摘要:
Modifications to the surface of an electrode and/or the surfaces of the electrode material can improve battery performance. For example, the modifications can improve the capacity, rate capability and long cycle stability of the electrode and/or may minimize undesirable catalytic effects. In one instance, metal-ion batteries can have an anode that is coated, at least in part, with a metal fluoride protection layer. The protection layer is preferably less than 100 nm in thickness.
摘要:
Disclosed are developments in high temperature fuel cells including ionic liquids with high temperature stability and the storage of inorganic acids as di-anion salts of low volatility. The formation of ionically conducting liquids of this type having conductivities of unprecedented magnitude for non-aqueous systems is described. The stability of the di-anion configuration is shown to play a role in the high performance of the non-corrosive proton-transfer ionic liquids as high temperature fuel cell electrolytes. Performance of simple H2(g) electrolyte/O2(g) fuel cells with the new electrolytes is described. Superior performance both at ambient temperature and temperatures up to and above 200° C. are achieved. Both neutral proton transfer salts and the acid salts with HSO−4 anions, give good results, the bisulphate case being particularly good at low temperatures and very high temperatures. The performance of all electrolytes is improved by the addition of a small amount of involatile base of pKa value intermediate between those of the acid and base that make the bulk electrolyte. The preferred case is the imidazole-doped ethylammonium hydrogensulfate which yields behavior superior in all respects to that of the industry standard phosphoric acid electrolyte.
摘要:
Orthoborate salts suitable for use as electrolytes in lithium batteries and methods for making the electrolyte salts are provided. The electrolytic salts have one of the formulae (I). In this formula anionic orthoborate groups are capped with two bidentate chelating groups, Y1 and Y2. Certain preferred chelating groups are dibasic acid residues, most preferably oxalyl, malonyl and succinyl, disulfonic acid residues, sulfoacetic acid residues and halo-substituted alkylenes. The salts are soluble in non-aqueous solvents and polymeric gels and are useful components of lithium batteries in electrochemical devices.
摘要:
Non-aqueous electrolyte solutions capable of protecting negative electrode materials such as lithium metal and carbonaceous materials in energy storage electrochemical cells (e.g., lithium metal batteries, lithium ion batteries and supercapacitors) include an electrolyte salt, a non-aqueous electrolyte solvent mixture, an unsaturated organic compound 4-methylene-1,3-dioxolan-2-one or 4,5-dimethylene-1,3-dioxolan-2-one, and other optional additives. The 1,3-dioxolan-2-ones help to form a good solid electrolyte interface on the negative electrode surface.
摘要:
The use of lithium bis(oxalate)borate (LiBOB) as an additive in a lithium secondary battery provides improved battery performance such as long life and high capacity retention after high temperature storage.