Abstract:
A design and process for making hermetically sealed thermocompression feedthrough and peripheral seal for high temperature Li Alloy FeS.sub.x battery cells and battery enclosures. The selected materials and processes parameters are developed to match the high temperature Li Alloy/FeS.sub.x system.
Abstract:
A pressure vessel for pressurized secondary cells is disclosed. The vessel includes a generally cylindrical container having both ends closed by substantially flat circular discs. The container has a diameter dimension substantially greater than its axial dimension. A mechanism is provided for supporting a plurality of substantially rectangular stacked electrode plates within the container. A pair of sealed terminal connectors pass through the container, and a terminal assembly mechanism is disposed within the container for directly interconnecting the stacked plates to each terminal connector.
Abstract:
The present disclosure relates to blended cathode materials for use as a positive electrode material of a rechargeable electrochemical cell (or secondary cell) (such as a lithium-ion secondary battery) and also relates to a secondary battery including a cathode having the blended cathode materials. In particular, disclosed are blends of lithium vanadium fluorophosphate (LVPF) or a derivative thereof with one or more conventional cathode active materials in certain weight ratios thereof.
Abstract:
The present invention is notably directed to methods and systems for protecting a pre-charge circuit. The present invention is further directed to related computer-implemented program product. The method comprises monitoring the current flowing through the current limiting device, calculating the energy loading of the current limiting device over time, and managing the system state to prevent damaging operation of the pre-charge circuit.
Abstract:
Provided are an electrolyte for low temperature operation of lithium titanate electrodes, graphite electrodes, and lithium-ion batteries as well as electrodes and batteries employing the same. The electrolyte contains 1 to 30 vol % of a low molecular weight ester having a molecular weight of less than 105 g/mol and at least one non-fluorinated carbonate. An electrolyte additive may include 0.1 to 10 wt % of fluorinated ethylene carbonate, particularly when used with a graphite anode. Another electrolyte contains a high content of the low molecular weight ester of at least 70 vol %.
Abstract:
The invention is directed to a system for controlling battery current. In some embodiments, the system comprises a first lithium-ion (Li-ion) battery, the first battery having a first state-of-charge (SOC) and comprising a first battery controller and a first battery charger; and a second Li-ion battery in series with the first battery, the second battery having a second SOC and comprising a second battery controller and a second battery charger. In some embodiments, at least one of the first battery controller or the second battery controller controls a charge current flowing through at least one of the first battery and the second battery, wherein control of the charge current is transferred from the first battery to the second battery based at least partially on whether an overhead voltage is present across the first battery charger or the second battery charger.
Abstract:
This invention relates to a supercapacitor assembly having an asymmetric supercapacitor, a diode, and a switch in parallel with the diode. The asymmetric supercapacitor has at least one positive electrode, at least one negative electrode, and at least one separator impregnated with an electrolyte. The diode has an anode and a cathode, the cathode being electrically connected to the supercapacitor.
Abstract:
An electrochemical cell, including a jelly-roll type electrode stack, and a method for making such cell. The electrochemical cell includes folded electrode portions which form a plane recessed from the end of the electrode stack. The folded electrode portions are preferably formed by making pairs of slits in the electrode end and bending over the electrode portions between each pair of slits. The recessed plane forms a large area to which a current collection tab is subsequently connected. A coating may be applied to the folded portions of the electrode to further increase the contact area with the current collection tab by eliminating the slight variations in the recessed plane which are due to the overlap of the folded electrode portions.
Abstract:
A pressure venting device for a battery casing includes two semi-circular concavities extending upwardly from the bottom surface of the casing, two oppositely disposed bridges interrupting the concavities and two weakening or score lines disposed laterally and offset from the bridges. Since the score lines are formed in a flat area of the bottom surface of the battery casing, venting will occur consistently at a predetermined pressure range.
Abstract:
A pressure relief vent on a container includes a flat diaphragm fastened to the exterior of a container so as to cover an opening in the container. The diaphragm is fastened to the container at its perimeter and at at least one point within its perimeter. The shape of the peripheral fastening seam and the number of and size of the point fastenings determine and stabilize the vent pressure at which the diaphragm ruptures.