Abstract: The cadmium negative electrode has a structure serving as a collector and made of nickel foam. The sponge is filled with a mixture consisting mainly of cadmium oxide and contains nickel sulphate in the proportion of 1.8 to 2.7% by weight of the total mixture, expressed in the form of nickel.

Abstract: A cadmium electrode for use in a rechargeable cell employing an alkaline electrolyte is disclosed. The electrode includes an electrically conductive substrate supporting an electrochemically active cadmium material. In addition, an effective amount of a nonionic, water soluble glycoside-based surfactant is added to retard cadmium agglomeration during operation of the electrode. Finally, a process for making such an electrode is also disclosed.

Abstract: The present invention discloses an enclosed alkaline storage cell. The enclosed alkaline storage cell comprising a negative electrode made of materials including a main active material of cadmium oxide, a positive electrode, and a separator impregnated with an alkaline electrolytic solution and interposed therebetween, characterized in that the negative electrode has a product produced by cross linking reaction between high polymers having hydroxyl group and at least one of boric acid and boric acid salt inside and/or on the surface thereof.

Abstract: An alkaline nickel-cadmium storage battery in which the active material with which the negative electrode is filled with, or the electrolyte in the storage battery, contains polyvinylpyrrolidone as an expander. Polyvinylpyrrolidone compounds having a mean molecular weight of 5,000 to 35,000 g/mol have proved particularly advantageous.

Abstract: A nickel-cadmium storage battery with improved electrical properties is described in which one or more copolymers of vinyl pyrrolidone is/are added as expander to the active material with which the negative electrode is filled or to the electrolyte. The polymers have a mean molecular weight of 10,000 g/mol to 100,000 g/mol, with a vinyl pyrrolidone content of between 5 and 95 mol-%. The copolymers are added to the active material or to the electrolyte in an amount of 0.1 to 1.0% by weight, based on the active material. As a result of adding the copolymers, a malfunction-free operation of the storage battery is achieved, accompanied by a simultaneously equally as good degree of utilization of the cadmium active material compared with a storage battery which contains homopolymeric polyvinyl pyrrolidone.

Abstract: A rechargeable alkaline storage cell comprising a positive electrode including an active material which mainly comprises nickel hydroxide added with zinc or a zinc compound. The cell further comprises a negative electrode and an alkaline electrolyte which mainly includes potassium hydroxide. The electrolyte also includes lithium hydroxide and sodium hydroxide.

Abstract: A rechargeable battery has a pair of electrodes, one having nickel hydrox as the active component and the other comprising as active component an amorphous alloy of at least one element selected from the group consisting of early transition metals and rare earth metals; and at least one late transition metal; the battery displays superior characteristics as compared with conventional Ni-Cd rechargeable batteries; essentially the battery functions as a hydrogen cell, involving intercalation of hydrogen into the amorphous alloy; a new method of charging involves charging a rechargeable cell and periodically interrupting the charging for a short interval and electrically shorting the cell during the short interval.

Abstract: Negative cadmium electrode for a non-sealed alkaline storage battery comprising a metal support to which is bonded an active paste containing a cadmium-based active material and a binder. The active paste additionally includes a material that acts as a hydrogen releasing catalyst, in a proportion of 0.2 percent to 25 percent by weight of the paste.

Abstract: This invention is to provide a nickel-cadmium alkaline storage battery in which the content of nickel hydroxide and/or nickel oxide in a negative active material is from 2 to 60 wt% based on the total amount of cadmium, and the content of cadmium hydroxide in the negative active material is 0.95 or lower in terms of a weight ratio to nickel hydroxide in a positive active material; a manganese dioxide-cadmium alkaline storage battery in which the content of cadmium hydroxide in a negative active material in the discharged state is 0.84 or lower in terms of a weight ratio to manganese dioxide in a positive active material; and a silver oxide-cadmium alkaline storage battery in which the content of cadmium hydroxide in a negative active material in the discharged state is 1.36 or lower in terms of a weight ratio to silver in a positive active material.

Abstract: The present invention provides a process for easily preparing .gamma.-Cd(OH).sub.2. The present invention facilitates improvement in the charge/discharge performance and energy density of an alkaline secondary battery having a cadmium electrode including .gamma.-Cd(OH).sub.2. The present invention provides superrapid-chargeable batteries, such as a nickel-cadmium alkaline secondary battery having a cadmium electrode including .gamma.-Cd(OH).sub.2 in which the weight of cadmium hydroxide contained in the negative electrode is 0.95 times as much as the weight of nickel hydroxide contained in the positive electrode, a manganese dioxide-cadmium alkaline secondary battery in which the weight of cadmium hydroxide contained in the negative electrode is not more than 0.84 times as much as the weight of manganese dioxide contained in the positive electrode, and a silver oxide-cadmium alkaline secondary battery in which the weight of cadmium hydroxide contained in the negative electrode is not more than 1.

Abstract: A cadmium electrode for use in rechargeable alkaline cells is disclosed featuring use of dispersed polyamide having specific properties. The polyamide serves as a binder as well as an anti-agglomerant to retard cadmium agglomeration during use of the electrode. The use of elemental silver additive dispersed throughout the electrode is also disclosed, as is the use of zirconium material as an elecrolyte wicking and anti-compressive agent. A process for making any of the foregoing electrodes is disclosed featuring the step of forming a paste by mixing together the polymeric resin, active cadmium material and a non-aqueous solvent, applying the paste to a conductive substrate and removing the solvent. Alternatively, known prefabricated cadmium electrodes, such as Teflon-bonded or sintered types, are post-treated through dipping or the like in a solution of the aforementioned polyamide.

Abstract: A rechargeable alkaline storage cell mainly comprising a negative electrode including polyvinyl pyrolidone having a degree of polymerization of 350 to 1,000, a positive electrode, and an alkaline electrolyte, and its manufacturing method are disclosed. This invention may be employed for the sintering method or for the non-sintering method of manufacturing a negative electrode.

Abstract: A paste-type cadmium electrode for use in an alkaline storage cell, comprising a conductive substrate, an active material layer mainly comprising cadmium oxide and formed on a surface of the conductive substrate, and a conductive layer or a nickel body formed on a surface of the active material layer.The conductive layer either has therein powdered carbon and powdered alkali-resistant metal having a surface area of 0.001 to 0.5 m.sup.2 against 1 g of the active material; comprises powdered carbon, a binder and powdered alkali-resistant metal having an apparent density of 0.2 g/cc or less; or comprises a first conductive layer formed on a surface of the active material layer and comprising powdered alkali-resistant metal and a binder, and a second conductive layer formed on a surface of the first conductive layer and comprising powdered carbon and a binder.The nickel body is dispersed on a surface of the active material layer, the nickel body comprising fiber-type nickel having an average fiber diameter of 1 .

Abstract: Overcharge protection, and especially the chargeability of a sealed Ni/Cd battery with high currents (up to 1 CA) is improved by rolling a carbon-containing powdered material into the surface of the negative electrode, which material catalyzes the reduction of oxygen. Wetting of the electrode with a "Tylose" dispersion prior to application of the powder (by powdering, vibration or in an agitator) improves the adhesion of the powder. The cadmium electrode thus prepared combines in itself the functions of a negative principal electrode and of an auxiliary oxygen electrode.

Abstract: A cadmium non-sintered negative electrode for use in an alkaline storage cell comprising a main active material comprising at least one of powdered cadmium oxide and powdered cadmium hydroxide; a reserve charging substance comprising powdered metal cadmium; and an additive comprising powdered nickel hydroxide whose grain shape is substantially globe and/or whose average grain size is 1.5 to 200 .mu.m.

Abstract: The present invention provides a paste type cadmium anode for alkali storage batteries which comprises an electrically conductive core material, an active material layer mainly composed of cadmium compounds and coated on the core material, an electrically conductive porous layer mainly composed of metallic nickel and provided on the surface of the active material layer, and an organic compound present between the active material layer mainly composed of cadmium compounds and the electrically conductive porous layer mainly composed of metallic nickel. This anode is improved in a cycle life owing to improvement in oxygen gas absorption and prevention of distortion of electrode plate.A method for making the anode is also provided.

Abstract: A wound electrode assembly for use in a sealed electrochemical cell. The wound electrode assembly has at least one electrode comprised of an electrically conductive substrate and an electrochemically active material secured to at least one face of the substrate. This one electrode defines an outer wrap for the electrode assembly. The electrochemically active material is absent from at least a portion of the exterior of the outer wrap to permit the first substrate in the outer wrap to contact at least a portion of the cell container into which the wound electrode assembly is positioned.

Abstract: A positive collector electrode with an active material which comprises a double hydroxide of the general formula[M.sup.2+ (1-x)Fe.sup.3+ x(OH).sub.2 ].sup.x+ [(x/n)X.sup.n-, yH.sub.2 O].sup.x-in which the transient parameter is 0.05.ltoreq.x.ltoreq.0.4, preferably 0.2, M.sup.2+ is preferably Ni.sup.2+, and X.sup.n- is an anion species, shows a remarkable improvement in electrical behavior as compared to analogous double hydroxides in which X.sup.n- is SO.sub.4.sup.2-, NO.sub.3.sup.- or CO.sub.3.sup.2-. These electrodes, known as siderophile electrodes, exhibit resistance to iron contamination if X.sup.n- is formed at least partly by PO.sub.4.sup.3- or HPO.sub.4.sup.2-. This improvement is manifested in a constancy of the specific discharge capacity at a high level over many cycles during charge/discharge operation as compared to a Cd/Cd(OH).sub.2 electrode. The process for producing the electrode is also disclosed.

Abstract: A rechargeable alkaline storage cell comprises, as main components thereof, a negative electrode, a positive electrode and an electrolyte. The negative electrode is formed of sintered type cadmium electrode including one of a polysaccharide and its derivative having a polymerization degree of more than 320.

Abstract: Alkaline Ni/Cd round cells (button cells) which are able to withstand long-term overloading with a relatively high current (five-hour current) for a practically unlimited time and still deliver approximately their rated capacity on discharge with an equal current after 12 months. The button cells of the invention comprise a negative electrode tablet provided with an auxiliary electrode comprising activated carbon integrated in the nickel wire gauze basket and a positive electrode constituted of a material which contains 20 wt. % to 35 wt. % metallic nickel as the second largest component of the mixture after Ni(OH).sub.2, while the otherwide common conductive graphite is absent.

Abstract: A primary element is provided which is dischargeable at high temperatures comprising an alkaline electrolyte in a metallic annular cylindrical housing which encloses in inwardly directed concentric order: an outer positive silver oxide or manganese dioxide electrode in the form of a pressed powder cylinder and an inner negative electrode comprising a concentrically wound cadmium electrode wherein said negative electrode is separated from said positive electrode by a separator interposed therebetween. In storage and testing it has been shown that cells produced in accordance with the present invention may be kept at temperatures of the order of 200.degree. C. for over six weeks without any loss of operability.

Abstract: A rechargeable alkaline storage cell and a method of manufacturing the cell. The manufacturing method mainly comprises a first step of forming a cadmium electrode by coating a conductive support with a kneaded active material in paste form including cadmium oxide as a main component thereof while suppressing hydration of the kneaded active material, and a second step of producing cadmium hydroxide through hydration of the cadmium oxide. The cell comprises, as main components thereof, a positive electrode including a rechargeable active material, a paste type negative cadmium electrode including cadmium hydroxide produced by chemical hydration, a separator disposed between the positive electrode and the negative electrode, and an electrolyte impregnating the separator.

Abstract: A rechargeable negative electrode for an electrochemical apparatus using nonaqueous electrolytes, said electrode comprising an alloy comprising (1) at least one metal selected from the group consisting of Sn, Pn, In and Bi and (2) Zn or Zn and Cd, as well as a rechargeable electrochemical apparatus comprising a combination of said negative electrode with a positive electrode having reversibility in charging and discharging. The above-mentioned negative electrode reversibly absorbs and desorbs alkali metal ions, as the result of charge and discharge, in nonaqueous electrolyte containing alkali metal ions. It undergoes no pulverization even after repeated charge and discharge, and maintains its shape stably, so that it has a long charge-and-discharge cycle life. Further, since it can absorb a large quantity of alkali metal per unit volume, it is of high energy density.

Abstract: A rechargeable electrochemical device comprising a cathode (6) composed chiefly of activated carbon, anode (3) composed of a lithium alloy, and an electrolyte composed of an organic solvent in which a lithium salt is dissolved. Lithium content in the lithium alloy forming the anode (3) is selected such that, if converted to the electric capacity under the charged condition, the capacity of this alloy ranges from 3 to 20 times the cathode capacity that is obtained when the cathode is discharged from 3.0V to 2.0V in a single-pole potential with respect to metal lithium. This constitution is able to provide a reliable rechargeable electrochemical device, which is proof against super-discharge and excellent in charge and discharge cycle life.

Abstract: A sealed storage battery comprises a positive electrode including a metallic oxide as an active material, a negative electrode including hydrogen-storage-alloy powder capable of electrochemically charging and discharging hydrogen as an active material, an alkaline electrolyte, and two separators (12a and 1 2b) for absorbing and retaining the alkaline electrolyte. The hydrogen-storage-alloy power has a crystal structure and is provided with numerous irregularities on the surface thereof, and has SF-value of 2.5 or below, which SF-value represents a plateau characteristic of equilibrium pressure of released hydrogen. The numerous irregularities on the surface of the alloy powder cause oxygen being generated from the positive electrode to be eliminated promptly.

Abstract: A rechargeable alkaline cell. Main components of the cell includes a positive electrode, a negative electrode, a separator, and a hydrophobic polymer. The negative electrode includes a conductive support, an active material layer formed on the conductive support, and a conductive layer formed on the active material layer. The separator is disposed between the positive and negative electrodes and impregnated with an alkaline electrolyte. The hydrophobic polymer is disposed between the separator and conductive powder of the conductive layer to be out of contact with the active material layer.

Abstract: Latex coated electrodes comprising a foraminous, electrically conductive substrate which supports a paste comprising a mixture of (a) finely divided, particulate, rechargeable, active material and, (b) a fibrous interconnecting network of an unsintered, uncoalesced, hydrophobic linear fluorocarbon polymer, wherein said active material is dispersed throughout and bound in said fibrous network and being accessible to said electrolyte and to gas being generated during overcharge of the cell have excellent mechanical integrity. These electrodes have a greater storage life than similar uncoated electrodes and rechargeable cells employing these electrodes have excellent electrical properties with respect to both voltage characteristics and pressure buildup.

Abstract: The cell of a gas-tight alkaline battery is balanced by subdividing the negative excess capacity into the necessary charge and discharge reserves by individually treating the two electrode polarities prior to their assembly, while avoiding open cell forming. When combining a charged, dried, positive sintered electrode which is suitable for storage with a negative electro-deposited electrode, the latter inherently receives a charge reserve due to partial chemical oxidation with H.sub.2 O.sub.2 l or K.sub.2 S.sub.2 O.sub.8. When a discharged, but preformed positive sintered electrode is combined with a negative sintered electrode, the latter is electrochemically partially charged to the extent necessary to achieve the desired discharge reserve, and thereafter preserved by immersion in a solution containing sulfuric acid, and possibly CdSO.sub.4.

Abstract: Undesirable heavy metal peroxides formed during the continuous partial oxidation of cadmium electrodes made from a charged strip of material, by means of H.sub.2 O.sub.2, to introduce a charge reserve prior to incorporation in a sealed alkaline battery cell, are removed by an immersion treatment in an alkaline hydroxide solution, with simultaneous desorption of oxygen and removal of the heat of hydrogenation. A subsequent boric acid immersion bath is used to neutralize introduced alkaline residues and to improve the stability of the strip during storage. The phenomena which accompany peroxide decomposition (intense evolution of heat and sputtering of electrolyte) in the completely assembled cell during the introduction of the electrolyte, and which interfere with the metering of the electrolyte, are thus avoided.

Abstract: A positive electrode for alkaline storage cells is disclosed. The active material for the positive electrode is a double hydroxide of the formula[M.sup.2+.sub.(1-x) Fe.sup.3+.sub.x (OH).sub.2 ].sup.x+ [(x/n)X.sup.n-..sub.y H.sub.2 O].sup.x-wherein x is in the range 0.05.ltoreq.x.ltoreq.0.4, M.sup.2+ is an oxidizable and reducible, and X.sup.n- is at least one anion. The double hydroxide has a pyroaurite-like double layer structure and is electrochemically resistant to iron poisoning. In a preferred embodiment, the double hydroxide comprises [Ni.sub.4 Fe(OH).sub.10 ].sup.30 [NO.sub.3.sup.-.yH.sub.2 O].sup.31 . Methods for preparing positive electrodes having the double hydroxide active material are also disclosed.

Abstract: A method of manufacturing a polymer-consolidated cadmium electrode for an alkaline storage cell, the method comprising the steps of:mixing the following ingredients in water: a gelling agent; cadmium and cadmium oxide in powder form constituting the active material; and a copolymer of carboxylated styrene-butadiene at a concentration lying in the range 0.5% to 3% by weight of active material;coating the resulting paste on a metal current collector;drying the coated current collector; andsubjecting the resulting assembly to a temperature lying in the range 120.degree. C. to 150.degree. C. for a period of a few minutes in order to cause said polymer to cross-link.

Abstract: The present invention relates to a rechargeable negative electrode for an electrochemical apparatus using nonaqueous electrolyte, said electrode comprising an alloy comprising Cd and at least one metal selected from the group consisting of Sn, Pb, In and Bi, as well as to a rechargeable electrochemical apparatus comprising a combination of said negative electrode with a positive electrode having reversibility in charge and discharge.The above-mentioned negative electrode reversibly absorbs and desorbs alkali metal ions, as the result of charge and discharge, in nonaqueous electrolyte containing alkali metal ions. It undergoes no pulverization even after repeated charge and discharge and maintains its shape stably, so that it has a long chargeand-discharge life. Further, since it can absorb a large quantity of alkali metal per unit volume, it is of high energy density.

Abstract: An alloy capable of reversibly absorbing and desorbing lithium ions in a non-aqueous electrolyte containing lithium ions on charging and discharging has excellent applicability to anode for rechargeable electrochemical devices. However, such alloy, when absorbed with lithium, loses its flexibility, so that when it is incorporated in a device in a charged state, it is subject to trouble such as cracking and can not display its properties. This invention adopts a method in which anode alloy is combined with lithium by connecting them so as to be electronically conductive to each other and this combination is fitted into the device, and then the electrolyte is supplied into the device to have lithium absorbed in anode alloy in the device. According to this method, cracking of cathode can be prevented.

Abstract: A rechargeable high energy density cell having a metal--metal oxide negative electrode, more specifically, the metal being cadmium, wherein the metal is in the form of thin flakes. Such cells show improved energy density and cycle life when charged-discharged at higher rate and to 100% depth of discharge.

Abstract: The cell of a gas-tight alkaline battery is balanced by subdividing the negative excess capacity into the necessary charge and discharge reserves by individually treating the two electrode polarities prior to their assembly, while avoiding open cell forming. When combining a charged, dried, positive sintered electrode which is suitable for storage with a negative electro-deposited electrode, the latter inherently receives a charge reserve due to partial chemical oxidation with H.sub.2 O.sub.2 or K.sub.2 S.sub.2 O.sub.8. When a discharged, but preformed positive sintered electrode is combined with a negative sintered electrode, the latter is electrochemically partially charged to the extent necessary to achieve the desired discharge reserve, and thereafter preserved by immersion in a solution containing sulfuric acid, and possibly CdSO.sub.4.

Abstract: Gassing is significantly reduced in electrochemical cells having anodes of polycrystalline metals, such as zinc, by heat treatment of the anode metal at a temperature below that of the melting point of the metal for a period of time sufficient to reduce the number of grains in the polycrystalline metal to at least a third of the original number of grains and thereafter using the metal in the formation of the cell anode. With such gassing reduction, the amount of mercury required for amalgamation with the zinc may also be reduced.

Abstract: The present invention provides a negative electrode plate for alkaline storage cells of the sealed type which comprises an active material layer formed on each of opposite surfaces of an electrically conductive carrier sheet from a paste composed chiefly of a cadmium oxide powder, and an electrically conductive layer comprising a carbon powder and formed over the surface of the active material layer, which gives e.g., greatly improved ability to absorb oxygen gas.

Abstract: A cadmium electrode for a rechargeable alkaline cell comprises a rigid substrate having particle-receiving recesses therein into and upon which are pressed a particulate mix of binder coated cadmium oxide particles and cadmium particles which constitute an active precharge anti-fading constituent of the mix. The binder coating may be a substantially insulating material, in which case the cadmium particles in various places are pressed into the substrate so that they penetrate through the binder coating to make direct contact with the cadmium oxide particles. The binder is most advantageously a curable butadiene polymer binder coating on the cadmium oxide particles preferably formed by heating an initial slurry of an emulsion of the binder and cadmium oxide particles to vaporize the liquid carrier and at least partially cure the binder material.

Abstract: An improved electrode coating and separator coating derived from a copolymer of diacetone acrylamide and a polymerizable monomer.This invention relates to novel rechargeable electrodes, separators and processes for preparing same.

Abstract: A divalent silver oxide cell having a negative electrode, a positive electrode mixture mainly of AgO, a separator between the negative electrode and the positive electrode mixture of an electrolyte. The positive electrode mixture contains Cd and Te so as to stabilize the AgO.

Abstract: An intimate mixture is prepared of a conductive metal powder and an active material in granular form. The mixture is then sintered by passing it through a variable magnetic field which is varied to produce trains of pulses in which the durations of the trains and intervals between trains are chosen in such a manner as to ensure that said metal powder is sintered without deteriorating said grains of active material.

Abstract: The invention is a high energy density electric cell having a lithium anode, and a copper oxide or cadmium oxide cathode. The electrolyte of the electric cell can be an organic solvent composed of propylene carbonate or nitromethane or a mixture of the two. The solute for the electrolyte is a soluble salt selected from the group of potassium hexafluorophosphate, lithium hexafluorophosphate and benzl trimethylammonium hexafluorophosphate.

Abstract: A cadmium electrode for a rechargeable alkaline cell comprises a rigid substrate having particle-receiving recesses therein into and upon which are pressed a particulate mix of binder coated cadmium oxide particles and cadmium particles which constitute an active precharge anti-fading constituent of the mix. The binder coating may be a substantially insulating material, in which case the cadmium particles in various places are pressed into the substrate so that they penetrate through the binder coating to make direct contact with the cadmium oxide particles. The binder is most advantageously a curable butadiene polymer binder coating on the cadmium oxide particles preferably formed by heating an initial slurry of an emulsion of the binder and cadmium oxide particles to vaporize the liquid carrier and at least partially cure the binder material.

Abstract: The addition of certain polymer compounds such as polybenzimidazole increases the capacity and cycle life of cadmium electrodes in nickel-cadmium batteries.

Abstract: A sulfide-containing cathode for nonaqueous cells such as AgBiS.sub.2, Co.sub.2 Bi.sub.2 S.sub.5, CoBi.sub.2 S.sub.4 and FeSb.sub.2 S.sub.4.

Abstract: The invention comprises an improved cadmium negative electrode which is less prone to fading, can easily be manufactured by a pasting technique, and which does not require any external cycling to develop a precharge. This is accomplished by the use of irregular knarled cylindroidal cadmium particles of an average size ranging from 8 to 25 microns as measured by a Fisher Subsieve Sizer. The irregular knarled cylindroidal shape of the particles provides a substantial improvement pyrophoric characteristics while stilll providing electrochemical activity within a nickel-cadmium cell.

Abstract: An improved electrode coating and separator coating derived from a copolymer of diacetone acrylamide and a polymerizable monomer.This invention relates to novel rechargeable electrodes, separators and processes for preparing same.

Abstract: A solid cathode for nonaqueous cells comprising complex metal sulfides such as PbFeS.sub.2, Co.sub.0.5 Fe.sub.1.5 S.sub.2, Co.sub.1.5 Fe.sub.0.5 S.sub.2 and CoFeS.sub.2.

Abstract: The electrode is formed from a permeable thin substrate constituted by an inorganic or organic substance whose porous or fibrous texture is such that the ratio between the effective surface and the boundary surface is large. This substrate is metallized over the entire effective surface, throughout its thickness, in order to constitute a charge collector. On this is then formed, over the entire effective surface, that is to say, throughout the thickness of the substrate, a thin deposit of active electrode material so that neither the porosity of the substrate nor the effective surface are substantially reduced.

Abstract: An improved electrode useful in electrochemical cells utilizes as the electrochemically active material zinc, zinc oxide, cadmium, cadmium oxide or a mixture of two or more of these materials. This electrochemically active material is preferably in the form of a shape-retaining body and is in direct contact with a novel current collector resistant to corrosion in strong alkaline electrolytes. The current collector is an alloy having at least about 40% of bismuth and at least about 25% of lead, by weight of the alloy. In one preferred embodiment the alloy consists entirely or essentially of bismuth and lead. In another embodiment, the alloy also includes at least one of the metals cadmium and tin. A useful collector can be formed by casting an alloy having about 50% bismuth, 27% lead, 13% tin and 10% cadmium, by weight of the alloy.