Hughes Aircraft Company

Hughes Electronics Corporation

Robert K Taenaka

Steven J Stadnick

John P Stafford

Barry G Gage

Walter R Oswald

Richard P Sernka

Walter Rex Oswald

Susan K Ferer

Michael Langmack

Patrick B Cooke

Michael A Allison

James M Hill

Matt H Russell

An electrochemical cell has electrode leads of different lengths extending from the terminals to the respective plate sets of the cell. The electrode leads have a cross-sectional area which varies along the length of the electrode leads, such that the electrical resistances of the electrode leads are substantially the same. Typically, each electrode lead has a first region having a first cross-sectional area, and a second region having a second cross-sectional area. The relative lengths of the first region and the second region of the electrode leads are varied to achieve the substantially constant total resistance.

Electrochemical cell with graded electrode leads

An electrical terminal provides an electrical interconnection between the exterior and the interior of the pressure vessel of an energy storage cell. The terminal includes an external electrical conductor exterior to the pressure vessel and an internal electrical conductor within the interior of the pressure vessel. An electrically nonconductive support mounts the electrical conductors to the wall of the pressure vessel. The two electrical conductors are cooperatively engaged, preferably by matching threads. A compliant seal is positioned between the external electrical conductor and the internal electrical conductor, on the one hand, and the wall of the pressure vessel, on the other, and a biasing washer set applies a force between the seal and the electrical conductors to maintain hermeticity in the event that the seal deforms during service.

Through-wall electrical terminal and energy storage cell utilizing the

A battery system includes a battery cell having a battery cell housing, and a housing support external to the battery cell housing. The housing support is formed of at least two split shell segments. Each split shell segment includes a heat conductor inner layer having a plurality of heat-conducting fibers with heat sink ends, and a structural support outer layer overlying the heat conductor inner layer. The structural support layer is made of a fiber-reinforced composite material. A layer of a structural adhesive bonds the respective heat conductor inner layer of each split shell segment to the battery cell housing. A thermal sink is in thermal contact with the sink ends of the plurality of heat-conducting fibers of each of the split shell segments, and the structural support outer layer of each split shell segment is joined to a structural base. Preferably, a number of the battery cells and overlying housing supports extend between a single thermal sink at one end and a single structure base at the other end, forming a battery pack.

Battery system with a high-thermal-conductivity split shell structural

A battery system comprises a plurality of sodium-sulfur storage cells connected in series to form a battery, with voltage measurement leads attached across each of the individual storage cells. A charge-limiting circuit controllably isolates an individual storage cell from a charging current applied across the battery when the measured voltage across that individual storage cell exceeds a preselected maximum storage cell voltage. Preferably, the charge-limiting circuit includes a bypass circuit connected through the voltage measurement leads and a circuit element that becomes conductive when the voltage across the individual storage cell exceeds the preselected maximum storage cell voltage. There are a plurality of charge-limiting circuits, one for each of the storage cells of the battery. In operation, a high charging current is imposed on the battery while measuring the voltage across each individual storage cell, until the voltage measured across at least one of the storage cells exceeds a preselected reduced-current voltage that is less than the preselected maximum storage cell voltage. The charging current is thereafter reduced to a low charging current while continuing to charge the battery. The low charging current is bypassed around each of the individual storage cells as that storage cell reaches the maximum voltage, until all of the storage cells reach the same state of charge.

Charge balancing of batteries during charging

A sodium-sulfur electrical storage cell (10) has a planar solid electrolyte (16) that is permeable to sodium ions, a planar permeable porous cathode (24) filled with sulfur, a planar permeable porous anode (28) filled with sodium, and an electrically nonconducting, closed flat container (12) for these elements. The electrolyte (16) is thin and strengthened, as by an integral supporting structure (22), or supported, as by a structural anode core structure (36) or by cross members (22) of the container, to minimize its deformation during operation. The anode (28) and cathode (24) are electrically conducting even without sodium and sulfur present, so that the cell (10) fails to a shorted state.

Planar sodium-sulfur electrical storage cell

Growing community of inventors

Granada Hills, CA, United States of America

Robert K Taenaka