Abstract: Provided are electrochemical cells and electrolytes used to build such cells. The electrolytes include ion-supplying salts and fluorinated solvents capable of maintaining single phase solutions with the salts at between about ?30° C. to about 80° C. The fluorinated solvents, such as fluorinated carbonates, fluorinated esters, and fluorinated esters, are less flammable than their non-fluorinated counterparts and increase safety characteristics of cells containing these solvents. The amount of fluorinated solvents in electrolytes may be between about 30% and 80% by weight not accounting weight of the salts. Fluorinated salts, such as fluoroalkyl-substituted LiPF6, fluoroalkyl-substituted LiBF4 salts, linear and cyclic imide salts as well as methide salts including fluorinated alkyl groups, may be used due to their solubility in the fluorinated solvents.

Abstract: Provided herein are methods for processing electrochemically active materials and resulting active material structures for use in rechargeable batteries. The resulting active materials structures include carbon containing coatings that partially or completely cover the surface of the active material structures. In a typical embodiment, the method includes providing a solution of carbon containing precursor in a solvent, dispersing electrochemically active material in the solution to form a mixture, removing the solvent from the mixture to form electrochemically active material coated with the carbon containing precursor, and heating the electrochemically active material coated with the carbon containing precursor in an inert atmosphere at a temperature sufficient to at least partially convert the carbon containing precursor into a carbon coating.

Abstract: Provided are electrochemical cells and electrolytes used to build such cells. An electrolyte may include a fluoroalkyl-substituted LiPF6 salt or a fluoroalkyl-substituted LiBF4 salt. In some embodiments, at least one fluorinated alkyl of the salt has a chain length of from 1 to 8 or, more specifically, between about 2 and 8. These fluorinated alkyl groups, in particular, relatively large fluorinated alkyl groups improve solubility of these salts in fluorinated solvents that are less flammable than, for example, conventional carbonate solvents. At the same time, the size of fluoroalkyl-substituted salts should be limited to ensure adequate concentration of the salt in an electrolyte and low viscosity of the electrolyte. In some embodiments, the concentration of a fluoroalkyl-substituted salt is at least about 0.5M.

Abstract: Provided herein are methods for processing electrochemically active materials for use in rechargeable batteries. The methods may also be practiced on electrodes and batteries containing such electrochemically active materials. In a typical embodiment, a method of chemically modifying the surface of an electrochemically active component of a battery is provided, the method including receiving the electrochemically active material and exposing the electrochemically active material to a gaseous reactant under conditions that chemically modify surfaces of the electrochemically active material that are accessible to the gaseous reactant, and thereby produce a modified electrochemically active material having improved properties for use in the battery.

Abstract: Provided are electrochemical cells and electrolytes used to build such cells. The electrolytes include ion-supplying salts and fluorinated solvents capable of maintaining single phase solutions with the salts at between about ?30° C. to about 80° C. The fluorinated solvents, such as fluorinated carbonates, fluorinated esters, and fluorinated esters, are less flammable than their non-fluorinated counterparts and increase safety characteristics of cells containing these solvents. The amount of fluorinated solvents in electrolytes may be between about 30% and 80% by weight not accounting weight of the salts. Fluorinated salts, such as fluoroalkyl-substituted LiPF6, fluoroalkyl-substituted LiBF4 salts, linear and cyclic imide salts as well as methide salts including fluorinated alkyl groups, may be used due to their solubility in the fluorinated solvents.

Abstract: Provided are electrochemical cells and electrolytes used to build such cells. An electrolyte may include a fluoroalkyl-substituted LiPF6 salt or a fluoroalkyl-substituted LiBF4 salt. In some embodiments, at least one fluorinated alkyl of the salt has a chain length of from 1 to 8 or, more specifically, between about 2 and 8. These fluorinated alkyl groups, in particular, relatively large fluorinated alkyl groups improve solubility of these salts in fluorinated solvents that are less flammable than, for example, conventional carbonate solvents. At the same time, the size of fluoroalkyl-substituted salts should be limited to ensure adequate concentration of the salt in an electrolyte and low viscosity of the electrolyte. In some embodiments, the concentration of a fluoroalkyl-substituted salt is at least about 0.5M.

Abstract: Provided are electrochemical cells and electrolytes used to build such cells. The electrolytes include imide salts and/or methide salts as well as fluorinated solvents capable of maintaining single phase solutions at between about ?30° C. to about 80° C. The fluorinated solvents, such as fluorinated carbonates, fluorinated esters, and fluorinated esters, are less flammable than their non-fluorinated counterparts and improve safety characteristics of cells containing these solvents. The amount of fluorinated solvents in electrolytes may be between about 30% and 80% by weight not accounting weight of the salts. Linear and cyclic imide salts, such as LiN(SO2CF2CF3)2, and LiN(SO2CF3)2, as well as methide salts, such as LiC(SO2CF3)3 and LiC(SO2CF2CF3)3, may be used in these electrolytes. Fluorinated alkyl groups enhance solubility of these salts in the fluorinated solvents. In some embodiments, the electrolyte may also include a flame retardant, such as a phosphazene, and/or one or more ionic liquids.

Abstract: Provided are electrochemical cells and electrolytes used to build such cells. An electrolyte includes at least one salt having a molecular weight less than about 250. Such salts allow forming electrolytes with higher salt concentrations and ensure high conductivity and ion transport in these electrolytes. The low molecular weight salt may have a concentration of at least about 0.5M and may be combined with one or more other salts, such as linear and cyclic imide salts and/or methide salts. The concentration of these additional salts may be less than that of the low molecular weight salt, in some embodiments, twice less. The additional salts may have a molecular weight greater than about 250. The electrolyte may also include one or more fluorinated solvents and may be capable of maintaining single phase solutions at between about ?30° C. to about 80° C.

Abstract: Provided herein are methods for processing electrochemically active materials for use in rechargeable batteries. The methods may also be practiced on electrodes and batteries containing such electrochemically active materials. In a typical embodiment, a method of chemically modifying the surface of an electrochemically active component of a battery is provided, the method including receiving the electrochemically active material and exposing the electrochemically active material to a gaseous reactant under conditions that chemically modify surfaces of the electrochemically active material that are accessible to the gaseous reactant, and thereby produce a modified electrochemically active material having improved properties for use in the battery.

Abstract: Provided herein are methods for processing electrochemically active materials and resulting active material structures for use in rechargeable batteries. The resulting active materials structures include carbon containing coatings that partially or completely cover the surface of the active material structures. In a typical embodiment, the method includes providing a solution of carbon containing precursor in a solvent, dispersing electrochemically active material in the solution to form a mixture, removing the solvent from the mixture to form electrochemically active material coated with the carbon containing precursor, and heating the electrochemically active material coated with the carbon containing precursor in an inert atmosphere at a temperature sufficient to at least partially convert the carbon containing precursor into a carbon coating.

Abstract: Provided are electrochemical cell assemblies and methods of fabricating thereof. A cell assembly includes an anode containing lithium titanium oxide and a cathode forming a jellyroll together with the anode. Each of the electrodes is connected to a separate cap and electrically insulated from the case. As such, the case is electrochemically neutral and may be made from a larger selection of materials. For example, a case may be made from steel that would otherwise dissolve if exposed to the anode potential during cycling of the battery. Some of these case materials simplify processing and sealing characteristics. In certain embodiments, a case may be crimped around each of the caps and corresponding gaskets to provide sealing interfaces. The caps or at least their surfaces exposed to the electrolyte are made from materials that are electrochemically stable at corresponding potentials of the electrodes.

Abstract: The present invention provides electrochemical cells and batteries having one or more electrically conductive tabs and carbon sheet current collectors, where the tabs are connected to the carbon sheet current collectors; and methods of connecting the tabs to the carbon based current collectors. In one embodiment, the electrically conductive tabs are metallic tabs.

Abstract: Disclosed herein are lithium or lithium-ion batteries that employ an aluminum or aluminum alloy current collector protected by conductive coating in combination with electrolyte containing aluminum corrosion inhibitor and a fluorinated lithium imide or methide electrolyte which exhibit surprisingly long cycle life at high temperature.

Abstract: The present invention provides electrochemical cells and batteries having one or more electrically conductive tabs and carbon sheet current collectors, where the tabs are connected to the carbon sheet current collectors; and methods of connecting the tabs to the carbon based current collectors. In one embodiment, the electrically conductive tabs are metallic tabs.

Abstract: Disclosed herein are lithium or lithium-ion batteries that employ an aluminum or aluminum alloy current collector protected by conductive coating in combination with electrolyte containing aluminum corrosion inhibitor and a fluorinated lithium imide or methide electrolyte which exhibit surprisingly long cycle life at high temperature.

Abstract: Disclosed herein are lithium or lithium-ion batteries that employ an aluminum or aluminum alloy current collector protected by conductive coating in combination with electrolyte containing aluminum corrosion inhibitor and a fluorinated lithium imide or methide electrolyte which exhibit surprisingly long cycle life at high temperature.

Abstract: A lithium oxyhalide cell electrically connected in parallel with a lithium ion cell is described. Importantly, the open circuit voltage of the freshly built primary lithium oxyhalide cell is equal to or less that the open circuit voltage of the lithium ion cell in a fully charged state. This provides a power system that combines the high capacity of the primary cell with the high pulse power of the secondary cell. This hybrid power system exhibits increased rate capability, higher capacity and improved safety in addition to elimination of voltage delay in comparison to a comparable lithium oxyhalide cell discharge alone.

Abstract: The present invention provides electrochemical cells and batteries having one or more electrically conductive tabs and carbon sheet current collectors, where the tabs are connected to the carbon sheet current collectors; and methods of connecting the tabs to the carbon based current collectors. In one embodiment, the electrically conductive tabs are metallic tabs.

Abstract: A lithium oxyhalide cell electrically connected in parallel with a lithium ion cell is described. Importantly, the open circuit voltage of the freshly built primary lithium oxyhalide cell is equal to or less that the open circuit voltage of the lithium ion cell in a fully charged state. This provides a power system that combines the high capacity of the primary cell with the high pulse power of the secondary cell. This hybrid power system exhibits increased rate capability, higher capacity and improved safety in addition to elimination of voltage delay in comparison to a comparable lithium oxyhalide cell discharge alone.