Abstract: Methods are provided for making bipolar electrochemical devices, such as batteries, using electrophoresis. A bipolar device is assembled by applying a field that creates a physical separation between two active electrode materials, without requiring insertion of a discrete separator film or electrolyte layer.

Abstract: A method of determining state of charge of an energy delivery device includes sampling voltage values of the energy delivery device during relaxation of the device. The method further includes regressing an open circuit voltage value and the total overpotential being relaxed. The regression includes a predetermined time constant of relaxation associated with the energy delivery device. One embodiment uses the equation V(t)=OCV?? exp(?t/tau), where V(t) represents the sampled voltage values, t represents times at which each of the voltage values are sampled, OCV represents the open circuit voltage value of the energy delivery device, ? represents the overpotential value, and tau represents the time constant of relaxation. The method uses a predetermined profile that relates open circuit voltage of the energy delivery device to state of charge of the device, to determine a particular state of charge corresponding to the regressed open circuit voltage value.

Abstract: Exemplary embodiments of the present invention provide flexible, multi-voltage battery modules having multiple cells that are nested together. The cells can be, for example, cylindrical lithium ion cells. To increase cell package density, the cells can be disposed in a nested configuration so that adjacent cell centers form equilateral triangles. The cells can be placed in a housing or case with interlocking tabs that allow multiple modules to be connected together. Within a module, the cells can be connected in different configurations by buss bars at the top and the bottom of the battery cells. The different configurations may provide different voltages for the module.

Abstract: A system for charging a battery includes a battery pack having at least two lithium ion cells. A controller detects a rate of change of voltage with respect to a state of charge (dV/dSOC) of the battery pack based on a calculated dV/dSOC that represents the battery pack as a whole, without calculating dV/dSOC individually on a cell-by-cell basis. Charging is terminated when dV/dSOC reaches a predetermined value.

Abstract: An energy storage device includes a first electrode comprising a first material and a second electrode comprising a second material, at least a portion of the first and second materials forming an interpenetrating network when dispersed in an electrolyte, the electrolyte, the first material and the second material are selected so that the first and second materials exert a repelling force on each other when combined. An electrochemical device, includes a first electrode in electrical communication with a first current collector; a second electrode in electrical communication with a second current collector; and an ionically conductive medium in ionic contact with said first and second electrodes, wherein at least a portion of the first and second electrodes form an interpenetrating network and wherein at least one of the first and second electrodes comprises an electrode structure providing two or more pathways to its current collector.

Abstract: A composite material having utility as an anode for lithium ion batteries comprises silicon, a transition metal, a ceramic and an electrically conductive diluent such as carbon. In particular instances, the ceramic is electrically conductive, and may comprise vanadium carbide or tungsten carbide. The transition metal may, in some instances, comprise iron. The material may be fabricated by grinding together a starting mixture of the components, and grinding may be accomplished in a high impact ball milling process, and the grinding step may cause partial alloying of the silicon with the metal and/or carbon. Further disclosed is a method for making the material as well as electrodes which incorporate the material.

Abstract: An electrochemical cell is provided. The cell includes a plurality of electrode sheets separated by at least one separator sheet. A positive extension tab is attached to a current collecting tabs of positive electrode sheets, and a negative extension tab is attached to current collecting tabs of the negative electrode sheets. The dimensions of the positive extension tab and the negative extension tab are selected such that temperature difference between positive extension tab and the negative extension tab are minimized when the electrochemical cell is in use.

Abstract: Electroactive compositions are disclosed for use in lithium ion battery electrodes. The compositions, such as multifunctional mixed metal olivines, provide an electrochemical cell having a plurality of open circuit voltages at different states of charge. The compositions afford improved state-of-charge monitoring, overcharge protection and/or overdischarge protection for lithium ion batteries.

Abstract: A battery management system includes one or more lithium ion cells in electrical connection, each said cell comprising: first and second working electrodes and one or more reference electrodes, each reference electrode electronically isolated from the working electrodes and having a separate tab or current collector exiting the cell and providing an additional terminal for electrical measurement; and a battery management system comprising a battery state-of-charge monitor, said monitor being operable for receiving information relating to the potential difference of the working electrodes and the potential of one or more of the working electrodes versus the reference electrode.

Abstract: An electrochemical cell, such as Li-Ion, having (a) a positive electrode; (b) a negative electrode, (c) a porous inorganic/organic composite layer interposed between the positive electrode and the negative electrode, and (d) an electrolyte comprising a lithium salt and a non-aqueous solvent. The composite layer includes inorganic nanoparticles and a binder to form a nanocomposite separator (NCS). In addition to the composite layer, the electrochemical cell includes a porous separator.

Abstract: Porous separators for use in electrochemical cells and methods of their manufacture are provided. The separators are porous structures comprising an electroactive material and an electronically insulating structural material, wherein the electroactive material forms a percolating path in the separator.

Abstract: In some embodiments, a battery cell can include an assembly having an anode sheet and a cathode sheet separated by separator membranes, each sheet having an electroactive layer on a current collector. At least one of the current collectors can be in electrical communication with conducting tabs that extend from at least one of the anode sheet and the cathode sheet, the conducting tabs extends from an end face of the spirally wound assembly. In addition, the cell can include a first tab insulator having concentrically positioned outer and inner members, each of the outer and inner members having at least one slot that allows one or more of the plurality of conducting tabs to pass through. The inner and outer members are adjustable with respect to relative angular orientation of the at least one slot on the outer and inner members of the first tab insulator.

Abstract: An electrochemical device includes a first electrode in electrical communication with a first current collector, a second electrode in electrical communication with a second current collector and a crosslinked solid polymer in contact with the first and second electrodes. At least one of the first and second electrodes includes a network of electrically connected particles comprising an electroactive material, and the particles of one electrode exert a repelling force on the other electrode when the first and second electrodes are combined with an uncrosslinked precursor to the solid polymer.

Abstract: A high capacity, high charge rate lithium secondary cell includes a high capacity lithium-containing positive electrode in electronic contact with a positive electrode current collector, said current collector in electrical connection with an external circuit, a high capacity negative electrode in electronic contact with a negative electrode current collector, said current collector in electrical connection with an external circuit, a separator positioned between and in ionic contact with the cathode and the anode, and an electrolyte in ionic contact with the positive and negative electrodes, wherein the total area specific impedance for the cell and the relative area specific impedances for the positive and negative electrodes are such that, during charging at greater than or equal to 4C, the negative electrode potential is above the potential of metallic lithium.

Abstract: An electrochemical device includes a first electrode in electrical communication with a first current collector, a second electrode in electrical communication with a second current collector and a crosslinked solid polymer in contact with the first and second electrodes. At least one of the first and second electrodes includes a network of electrically connected particles comprising an electroactive material, and the particles of one electrode exert a repelling force on the other electrode when the first and second electrodes are combined with an uncrosslinked precursor to the solid polymer.

Abstract: A high capacity, high charge rate lithium secondary cell includes a high capacity lithium-containing positive electrode in electronic contact with a positive electrode current collector, said current collector in electrical connection with an external circuit, a high capacity negative electrode in electronic contact with a negative electrode current collector, said current collector in electrical connection with an external circuit, a separator positioned between and in ionic contact with the cathode and the anode, and an electrolyte in ionic contact with the positive and negative electrodes, wherein the total area specific impedance for the cell and the relative area specific impedances for the positive and negative electrodes are such that, during charging at greater than or equal to 4C, the negative electrode potential is above the potential of metallic lithium.

Abstract: A system for balancing energy delivery devices within the one or more battery packs and for providing isolated monitoring of the battery packs includes at least one group of energy delivery devices electrically connected in series. For each group of energy delivery devices, the system includes a balancing circuit for each adjacent pair of energy delivery devices. The balancing circuit adjusts charge stored in each energy delivery device of the pair so that the charge stored in the energy delivery devices of the pair is substantially equal, and the charge stored in each energy delivery device remains above a threshold. The system also includes a voltage monitoring module for sequentially selecting each of the energy delivery devices and providing a voltage associated with the selected device at an output port. The voltage monitoring module uses a low on-resistance differential multiplexer to select each of the energy delivery devices.

Abstract: Compositions and methods are provided for coating electroactive particles. Coating materials include a conductive component and a low refractive index component. Coatings are provided in which the conductive and low refractive index components are linked and/or do not form phases having lengthscales greater than about 0.25 ?m. Coatings are provided in which the components are contained in sequential layers.

Abstract: An energy delivery system includes at least one string of two or more energy delivery modules electrically coupled in series. Each energy delivery module includes one or more energy delivery devices for storing and delivering electrical current, and a module monitor for monitoring and controlling each of the energy delivery devices. Each string of energy delivery modules includes a string communication path accessible to each of the energy delivery modules, wherein the module monitor of each energy delivery module is operable to communicate information associated with its energy delivery module through the string communication path. Each string also includes a string manager device for communicating with each module monitor in the string, through the string communication path. The energy delivery system also includes a system controller for communicating with each string manager device through a system communication path.

Abstract: A compact, robust, multifunctional and highly manufacturable rechargeable cylindrical electrochemical cell is provided. In some embodiments, a cell can include a spirally wound assembly having an anode sheet and a cathode sheet separated by separator membranes, each sheet having a electroactive layer on a current collector. At least one of the current collectors can be in electrical communication with conducting tabs that extend from at least one of the anode sheet and the cathode sheet, the conducting tabs extends from an end face of the spirally wound assembly. The centers of the plurality of conducting tabs can be located within a 90 degree quadrant of an end face of the spirally wound assembly.