Patents Assigned to Energy Development Associates, Inc.
  • Patent number: 4400446
    Abstract: A metal halogen battery system, said system having the following construction, a store means constructed in the form of a container which includes a generally unitary filter means extending around most of the inside surface of the container and with the filter means being spaced a predetermined distance away from said surface to form spacing between the filter means and the inside surface, said filter means being operative to separate the hydrate formed from the liquid electrolyte, a hydrate former-gas pump means associated with the store means and being operative to intermix halogen gas from the battery cell with aqueous electrolyte from the store means and from the cell, a gas space means being maintained at the top of the store means with the hydrate former-pump means exhausting into the proximity of the gas space, said gas space means being operative to reduce transfer of liquid from the store to the cell, exit conduit means generally adjacent the top of the store means for transmitting fluid containing h
    Type: Grant
    Filed: March 12, 1982
    Date of Patent: August 23, 1983
    Assignee: Energy Development Associates, Inc.
    Inventor: Thomas H. Hacha
  • Patent number: 4399200
    Abstract: In a system for controlling the flow rates in a storage battery of the type having at least one pump driven at a controlled speed by a motor driven at a speed determined by the average applied voltage and the load experienced by the pump, which system includes a circuit for applying an average voltage to the motor and means for generating a reference signal for controlling the general magnitude of the average applied voltage to drive the pump at the desired speed, there is provided an improvement.
    Type: Grant
    Filed: November 5, 1981
    Date of Patent: August 16, 1983
    Assignee: Energy Development Associates, Inc.
    Inventor: James H. Galloway
  • Patent number: 4389468
    Abstract: A metal halogen battery system, including at least one cell having a positive electrode and a negative electrode contacted by aqueous electrolyte containing the material of said metal and halogen, store means whereby halogen hydrate is formed and stored as part of an aqueous material, means for circulating electrolyte through the cell and to the store means, and conduit means for transmitting halogen gas formed in the cell to a hydrate former whereby the hydrate is formed in association with the store means, said store means being constructed in the form of a container which includes a filter means, said filter means being inoperative to separate the hydrate formed from the electrolyte, said system having, a hydrate former pump means associated with the store means and being operative to intermix halogen gas with aqueous electrolyte to form halogen hydrate, said hydrate former means including, multiple outlet nozzle means connected with the outlet side of said pump means and being operative to minimize pluggi
    Type: Grant
    Filed: March 16, 1982
    Date of Patent: June 21, 1983
    Assignee: Energy Development Associates, Inc.
    Inventor: Harry K. Bjorkman, Jr.
  • Patent number: 4386140
    Abstract: An improved hydrate store for a metal halogen battery system is disclosed which employs a multiple stage, multiple filter means or separating the halogen hydrate from the liquid used in forming the hydrate. The filter means is constructed in the form of three separate sections which combine to substantially cover the interior surface of the store container. Exit conduit means is provided in association with the filter means for transmitting liquid passing through the filter means to a hydrate former subsystem. The hydrate former subsystem combines the halogen gas generated during the charging of the battery system with the liquid to form the hydrate in association with the store. Relief valve means is interposed in the exit conduit means for controlling the operation of the separate sections of the filter means, such that the liquid flow through the exit conduit means from each of the separate sections is controlled in a predetermined sequence.
    Type: Grant
    Filed: April 16, 1982
    Date of Patent: May 31, 1983
    Assignee: Energy Development Associates, Inc.
    Inventor: Harry K. Bjorkman, Jr.
  • Patent number: 4385099
    Abstract: An improved electrical energy storage system comprising, at least one cell having a positive electrode and a negative electrode separated by aqueous electrolyte, a store means wherein halogen hydrate is formed and stored as part of an aqueous material having a liquid level near the upper part of the store, means for circulating electrolyte through the cell, conduit means for transmitting halogen gas formed in the cell to a hydrate forming apparatus associated with the store, said hydrate forming apparatus including, a pump to which there is introduced quantities of the halogen gas and chilled water, said pump being located in the store and an outlet conduit leading from the pump and being substantially straight and generally vertically disposed and having an exit discharge into the gas space above the liquid level in the store, and wherein said hydrate forming apparatus is highly efficient and very resistant to plugging or jamming.
    Type: Grant
    Filed: October 13, 1981
    Date of Patent: May 24, 1983
    Assignee: Energy Development Associates, Inc.
    Inventors: Walter L. Fong, Henry A. Catherino, Richard J. Kotch
  • Patent number: 4382113
    Abstract: A method of joining together a plurality of graphite members providing a low transition resistance is described. The method includes the steps of interposing a layer of a thermally sensitive material between the graphite members to be joined, applying pressure to force the graphite members together, applying sufficient heat to melt the thermally sensitive material, and releasing the pressure after providing a period of time for cooling. The thermally sensitive material is preferably composed from a thermoplastic material, and the heat for melting this material is preferably provided by resistance brazing.
    Type: Grant
    Filed: March 23, 1981
    Date of Patent: May 3, 1983
    Assignee: Energy Development Associates, Inc.
    Inventors: Stephan Schwartz, Olle Ramstrom, Ake Bjareklint
  • Patent number: 4371825
    Abstract: A method of minimizing the effect of parasitic currents in secondary batteries having a plurality of cells connected electrically in series and a common electrolyte in communication with the cells is described. Specifically, the parasitic currents flowing through the battery cause a cell imbalance over the charge/discharge cycle. This cell imbalance is minimized by first separating the cells of the battery into two equal groups. Then the battery is charged with the two groups of cells connected electrically in series, and subsequently discharged with the two groups of cells reconnected electrically in series in an inverted sequence.
    Type: Grant
    Filed: June 4, 1981
    Date of Patent: February 1, 1983
    Assignee: Energy Development Associates, Inc.
    Inventors: Michael C. Chi, Peter Carr
  • Patent number: 4343982
    Abstract: A method of joining two metal members to a graphite member to form a structure having a low transition resistance is described. The method includes the steps of providing a plurality of openings in the graphite member, interposing the graphite member between the two metal members and positioning the metal members to cover the openings in the graphite member, and resistance spot welding the metal members to the graphite member at the openings in the graphite member. This method is advantageous in forming a bus-bar connection between a pair of opposite polarity graphite electrodes in an electrochemical cell stack, such as a zinc-chloride battery. In this particular application, it is preferred that titanium be used for the metal members.
    Type: Grant
    Filed: March 23, 1981
    Date of Patent: August 10, 1982
    Assignee: Energy Development Associates, Inc.
    Inventors: Stephan Schwartz, Roland Soderstrom, Ake Bjareklint
  • Patent number: 4337237
    Abstract: When halogen is bubbled into a body of water in the presence of catalysts of graphitized carbon, ruthenised titanium, platinised titanium or mixtures thereof, hydrohalic acid is formed at higher concentrations than obtained by water by itself.
    Type: Grant
    Filed: September 10, 1980
    Date of Patent: June 29, 1982
    Assignee: Energy Development Associates, Inc.
    Inventor: Thomas G. Hart
  • Patent number: 4320179
    Abstract: Halogen and hydrohalic acid are transferred and purified in an auxiliary electrochemical cell divided into two compartments by a permselective membrane, one compartment containing a low chlorine oxidation overvoltage electrode and the other compartment containing a low chlorine reduction overvoltage electrode.
    Type: Grant
    Filed: April 3, 1978
    Date of Patent: March 16, 1982
    Assignee: Energy Development Associates, Inc.
    Inventor: Thomas G. Hart
  • Patent number: 4307159
    Abstract: This disclosure relates to a zinc halogen battery electrolyte composition containing an additive providing increased battery capacity. The improved electrolyte composition involves the use of a bismuth additive to inhibit undesirable irregular plating and reduce nodular or dendritic growth on the zinc electrode.
    Type: Grant
    Filed: March 28, 1980
    Date of Patent: December 22, 1981
    Assignee: Energy Development Associates, Inc.
    Inventors: Michael J. Hammond, Patricia H. Schultz, Vladimir Feiman
  • Patent number: 4306003
    Abstract: This disclosure relates to a zinc halogen battery electrolyte composition containing an additive providing improved zinc-on-zinc recyclability. The improved electrolyte composition involves the use of a lead additive to inhibit undesirable irregular plating and reduce nodular or dendritic growth on the electrode surface. The lead-containing electrolyte composition of the present invention appears to influence not only the morphology of the base plate zinc, but also the morphology of the zinc-on-zinc replate. In addition, such lead-containing electrolyte compositions appear to reduce hydrogen formation.
    Type: Grant
    Filed: March 28, 1980
    Date of Patent: December 15, 1981
    Assignee: Energy Development Associates, Inc.
    Inventor: Gary L. Henriksen
  • Patent number: 4306000
    Abstract: This disclosure relates to a method of cooling zinc halogen batteries which involves the use of a liquid-overfeed cooling system utilizing a fluorocarbon refrigerant or the like. This new method is adaptable for use in either cooling the battery store water during charge so that a solid halogen hydrate will form, or for use in cooling the battery electrolyte, or both. This direct-cooling, liquid-overfeed system is especially suited for use with a series of batteries as is proposed for use in utility load leveling systems and provides several advantages over other conventional cooling alternatives including an improved coefficient of performance, better heat transfer and temperature control, and reduced capital cost.
    Type: Grant
    Filed: April 29, 1980
    Date of Patent: December 15, 1981
    Assignee: Energy Development Associates, Inc.
    Inventor: Satyanarayana Kodali
  • Patent number: 4288507
    Abstract: Described is an electrode assembly comprising;a. a porous electrode having a first and second exterior face with a cavity formed in the interior between said exterior faces thereby having first and second interior faces positioned opposite the first and second exterior faces;b. a counter electrode positioned facing each of the first and second exterior faces of the porous electrode;c. means for passing an oxidant through said porous electrode; andd. screening means for blocking the interior face of the porous electrode a greater amount than the blocking of the respective exterior face of the porous electrode, thereby maintaining a differential of oxidant electrode surface between the interior face and the exterior face.The electrode assembly is useful in a metal, halogen, halogen hydrate electrical energy storage device.
    Type: Grant
    Filed: July 21, 1980
    Date of Patent: September 8, 1981
    Assignee: Energy Development Associates, Inc.
    Inventors: Peter Carr, Chen H. Chi
  • Patent number: 4288301
    Abstract: A method of forming hydrogen by electrolysis in a cell containing a hydrohalic acid produced from a reaction process using carbon particles as an input energy source wherein the acid for electrolysis is produced by reacting the electrolysis separated halogen with water and carbon particles in a reaction area communicated with the electrolysis cell. The reaction can also be made in the presence of a catalyst.
    Type: Grant
    Filed: October 18, 1979
    Date of Patent: September 8, 1981
    Assignee: Energy Development Associates, Inc.
    Inventor: Thomas G. Hart
  • Patent number: 4287267
    Abstract: A zinc-chlorine battery plant system and method of redirecting the electrical current around a failed battery module. The battery plant includes a power conditioning unit, a plurality of battery modules connected electrically in series to form battery strings, a plurality of battery strings electrically connected in parallel to the power conditioning unit, and a bypass switch for each battery module in the battery plant. The bypass switch includes a normally open main contact across the power terminals of the battery module, and a set of normally closed auxiliary contacts for controlling the supply of reactants electrochemically transformed in the cells of the battery module. Upon the determination of a failure condition, the bypass switch for the failed battery module is energized to close the main contact and open the auxiliary contacts.
    Type: Grant
    Filed: May 27, 1980
    Date of Patent: September 1, 1981
    Assignee: Energy Development Associates, Inc.
    Inventors: Curtis C. Whittlesey, Matthew S. Mashikian
  • Patent number: 4273839
    Abstract: Described is a method of activating a carbonaceous electrode comprising the steps;1. Providing a negative electrode and a carbonaceous positive electrode spaced apart from each other;2. Providing an aqueous electrolyte with a current carrying water soluble material therein; and3. Closing the circuit and passing a current between the positive and negative electrodes through the electrolyte thereby generating oxygen for a period of time sufficient to activate the positive electrode.The electrodes are useful in a metal halogen electrical energy storage device.
    Type: Grant
    Filed: July 30, 1979
    Date of Patent: June 16, 1981
    Assignee: Energy Development Associates, Inc.
    Inventors: Peter Carr, Alfred F. Laethem
  • Patent number: 4257867
    Abstract: An electrolytic cell for separating chlorine gas from other (foreign) gases, having an anode, a cathode assembly, an aqueous electrolyte, a housing, and a constant voltage power supply. The cathode assembly is generally comprised of a dense graphite electrode having a winding channel formed in the face opposing the anode, a gas impermeable (but liquid permeable) membrane sealed into the side of the cathode electrode over the channel, and a packing of graphite particles contained in the channel of the cathode electrode. The housing separates and parallelly aligns the anode and cathode assembly, and provides a hermetic seal for the cell. In operation, a stream of chlorine and foreign gases enters the cell at the beginning of the cathode electrode channel. The chlorine gas is dissolved into the electrolyte and electrochemically reduced into chloride ions. The chloride ions disfuse through the gas impermeable membrane, and are electrochemically oxidized at the anode into purified chlorine gas.
    Type: Grant
    Filed: March 28, 1980
    Date of Patent: March 24, 1981
    Assignee: Energy Development Associates, Inc.
    Inventors: Michael J. Hammond, Mark W. Arendell
  • Patent number: 4256554
    Abstract: An electrolytic cell for separating chlorine gas from other (foreign) gases, having an anode electrode, a cathode electrode, a gas impermeable (but liquid permeable) membrane interposed between the anode and cathode electrodes, an aqueous electrolyte, a housing, and a constant voltage power supply. The electrolytic cell may be constructed in either a rectangular or cylindrical geometry, and may be combined with other electrolytic cells to form a multiple cell system. In operation, a stream of chlorine and foreign gases enters the cell at the lower portion of the cathode electrode. The chlorine gas is dissolved into the electrolytic and electrochemically reduced into chloride ions. The chloride ions diffuse through the gas impermeable membrane, and are electrochemically oxidized at the anode into purified chlorine gas. The foreign gases do not participate in the above, and are vented from the cell.
    Type: Grant
    Filed: March 28, 1980
    Date of Patent: March 17, 1981
    Assignee: Energy Development Associates, Inc.
    Inventor: Harry K. Bjorkman, Jr.
  • Patent number: 4251568
    Abstract: A method for the useful storage of electrical energy is described in which an electrochemical cell employing a halide electrolyte and an ungraphitized carbon positive electrode is charged at a voltage substantially below the conventional decomposition voltage required to produce free halogen from the selected electrolyte. An unidentified chemical complex is formed and stored at the positive electrode, and the positive electrode may thereafter be employed as an electrical energy source in a primary or secondary battery.
    Type: Grant
    Filed: August 27, 1979
    Date of Patent: February 17, 1981
    Assignee: Energy Development Associates, Inc.
    Inventor: Thomas G. Hart