US2979553A - Current generator cell - Google Patents

Description

United States Patent CURRENT GENERATOR CELL John McCallum, Worthington, Ohio, Theodore B. Johnson, Stratford, Conn., and Walter E. Ditmars, Jr., and Leslie D. McGraw, Columbus, Ohio, assignors, by direct and mesne assignments, to Remington Arms Company, Inc., Bridgeport, Conn., a corporation of Delaware No Drawing. Filed Ian. 3, 1958, Ser. No. 706,890

10 Claims. (Cl. 136-100) No. 405,494, filed January 21, 1954. Each of these applications is now abandoned.

Itis well known that certain metals including aluminum, magnesium, and titanium in contact with many electrolytes acquire a surface film that effectively blocks the flow of electrons. of this property of such metals in the construction of such electrolytic apparatus as rectifiers, capacitors, and lightning arrestors. Titanium, by reason of its filmforming properties, has frequently been mentioned as a metal suitable for use in' electrolytic devices of this character. Because of such film-forming properties, titanium has not been seriously considered as a possible useful material for the negative electrode (anode) of a primary cell. V H

On the other hand, it is well known that certain electrolytes severely attack'titanium'l metal. Hydrofluoric" acid, for example, is commonly used .to. clean .titanium products, and hydrogen gas is vigorously evolved there: by. Red fumingnitric acid can attack titanium metal with explosive violence. Prior to this invention, then,

Advantage has long been taken 'ice greatly retarding the formation of nonconductive or rectifying films on the surfaces of various titanium alloys and instead maintain the surfaces substantially free from any current blocking film, and. permit the use of light! weight durable titanium alloys as primary cell negative electrodes (anodes); p

Certain preferred electrolytes provide best results .for various purposes. Propercombinations of negative. electrodes (anodes), electrolytes, and positive electrodes (cathodes), in accordance with this invention, provide novel primary cells that may be custom designed to have combinations of characteristics not obtained in prior cells. For example, such cells can be made to have long shelf life and low drain, or to provide high currents at high voltage, or to have small size and light weight. Combinations of these properties in various degrees can also be obtained.

The cathodes or depolarizers (positive electrodes) usedin cells of the present invention maybe-those well known in the art, such as mercuric oxide, lead dioxide, manganese dioxide, nickel oxides. The depolarizers (positive electrodes) may or may not be formed on special supports such asthe titanium supports of U.S.

Patent 2,631,115 of Fox. The support for the depolarizer (positive electrode) is another part of the cell, and has no material bearing on the function of the anode (negative electrode). The Fox patent asserts that titanium, used as a supporting structure for the depolarizer (the positive electrode. in. a current generating cell), improves the depolarizer voltage and operating characteristics without taking part in the electrochemical reaction. The titanium alloy anodes (negative electrodes) of the present invention have nothing to do with the behavior of the cell depolarizers or cathodes (positive electrodes) and the alloyanodes are "electrochemically consumed as an integral part of cell, discharge. Thesefacts are mentioned here to avoid any ,confusionbetween these two essentially different uses of titanium.

Primary cell anodes according to the present invention comprise titanium-rich alloys containing at least atomic percent titanium. The addition of alloying materials such as molybdenum, vanadium, chromium,

titanium Was regarded as either too passive because of current blocking films in many electrolytes, or too active because'of spontaneous corrosion by other electrolytes. Either situation rendered titanium substantially useless as a negative electrode (anode) for a primary cell.

It has been discovered as a part of the present invention that certain alloying elements added to titanium make titanium alloys that are electrochemically active, but at the same time prevent chemical activity and spontaneous corrosion. When the alloys are used as primary cell anodes (negative electrodes) both the titanium and the alloying elements are consumed in the delivery of useful energy. 7

By varying the type and amount of alloying elements added to titanium, in accordance with the present invention, the chemical and electrochemical properties of titanium can be controlled to provide novel primary cell anodes (negative electrodes) with a variety of desirable properties, depending on the desired end use. I

This invention includes the discovery that concentrated alkaline electrolytes have the property of inhibiting or cobalt, nickel,,ni0bium, tantalum, and tungsten, from periodic groups V, VI, and VIII decreases the sponta-' neous corrosion of the anode and thereby increases the shelf life of the cell. Such alloying elements can be called titanium passivating elements. Alloying. additions of materials such as aluminum, beryllium,fland boron, from periodic groups II and III, increasethe voltage and current capacity of the cell. ,Such alloying elements can be called voltage-improving and currentimproving elements. Various combinations of these and other materials may be used in titanium alloys to obtain desired properties, as described herein. The anodes of this invention are free from any substantial current blocking film and are in direct contact withthe electrolytes. The alloys are consumed in the discharge of cells by the flow of ions from the anodes to the electrolytes.

The present invention contemplates the use of alloys of titanium as the active anode materials that directly furnish electrical energy in primary cells. It has been discovered that many of these titanium alloys exhibit unique properties as primary cell anodes. In particular, certain alloy additions to titanium decrease. spontaneous corrosion thereby improving shelf life. Alloyingaddiabsence tions can also increase the closed circuit voltage of titanium containing cells, increase the available current density, or reduce the weight and size of the anode. Various combinations of these advantages may also be obtained by controlling the titanium alloy composition. The titanium alloy anodes may be made in the form of shaped solid alloys, rolled foils, sintered powders, or compressed powders, by methods well known in the primary cell art. It is important to avoid gross heterogeneity of the alloy, as nonuniformity may result in local galvanic action, which destroys shelf life of the cell. The electrolyte must contact the titanium alloy anode but it may be either liquid or gelled in accordance with common practices in the primary cell art. The cathode depolarizer may also be made in conventional forms and shapes,

- ANODE MATERIALS We have discovered that titanium alloys with various elements of groups V, VI, and VIII of the periodic table used as primary cell anodes have low enough spontaneous corrosion to provide long shelf life for the cells containing. them as anodes. In this group of alloys, increasing the concentration of the alloying addition results in increasing the chemical passivity of the anode. However, when the alloying addition is present in a certain minimum desired amount, further additions do not ap preciably affect the chemical passivity or corrosion resistance. For example, in a titanium molybdenum alloy, the corrosion resistance of the alloy in primary cell electrolytes gradually increases with increase in molybdenum concentration until the molybdenum concentration is about 25 to 29 weight percent. Further increases of molybdenum do not materially increase the corrosion resistance.

To illustrate this discovery, corrosion rates were measured by hydrogen evolution in saturated potassium hydroxide solutions containing a small amount of solubilized potassium tartrate. Results are shown in Table I below, together with anodic closed circuit voltages at an anode current density of 5.0 milliamperes per square inch. The closed circuit voltages are measured against a saturated calomel electrode (SCE) for purposes of experimentation. In primary cells containing this electrolyte, conventional cathodes such as mercuric oxide, nickel oxides, and manganese oxides may be used.

.4 v as described in the periodic table. Thus, titanium can be considered to have 4 valence electrons, vanadium 5, chromium 6, iron 8, cobalt 9, nickel l0, and so forth.

To illustrate this discovery, various titanium alloys were given corrosion tests in primary cell electrolytes, and the following results were obtained:

For best cell performance, the minimum amounts by weight of the passivating elements in titanium alloy anodes should be: 29 percent molybdenum, 13 percent vanadium, 18 percent chromium, 29- percent cobalt, 38 percent nickel, 24 percent niobium, 35 percent tantalum, and 39 percent tungsten.

To obtain optimum results in the chemical passivation of titanium by alloying, the alloy should be one phase and homogeneous. Titanium metal has a hexagonal closepacked crystaline structure below 882 C. When alloyed with some of the other transition metals, however, titanium assumes a body centered cubic crystalline structure in which greater solid solubility is possible. Titanium forms intermctallic compounds with some metals. It is important for optimum performance and minimum selfdischarge that only one crystalline structure be present for the entire alloy, and that mixed phases, structures, or compounds be absent. To illustrate this point, two Ti-30 Mo alloys were prepared, one by quenching the alloy rapidly from melting temperature, the other by slowly annealing from melting temperature to ambient room temperature over a period of days. Spontaneous corrosion tests were then made, as described earlier, and results were as follows:

Table I Closed Gassing Circuit Anode, Numbers Refer to Weight Percent Rate, cc. Voltage H /day-in. at 5.0

mar/in. vs. SCE 1 1 Saturated Calomel Electrode.

We have discovered further that this chemical passivation effect can be obtained by alloying titanium metal with other transition metals from periodic groups V, VI, and VIII. A certain minimum concentration of alloy additions appears to be desirable for the minimum of chemical activity plus maximum of electrochemical activity as a primary cell anode. It appears that there are electronic interactions between atoms of the alloys and when the total number of valence electrons is about five for each titanium atom, we have a preferred alloy for a primary cell anode. In this instance, valence electrons means the total number of electrons in the transition metal outside of the preceding inert gas electronic core Table III Gassing Alloy Rate, cc.

Hg/dZiY-HL Pl-30 Mo (quenched) 0.0021 Ti-30 Mo (slow annealed) 0.018

The slow annealed sample has a mixture of crystalline structures (hexagonal close packed plus body centered cubic). Each structure has a dilferent alloy composition, and corrosion resistance is thereby decreased.

Mixtures of various metals may be alloyed with titanium to decrease chemical activity and increase electrochemical activity. For best results, the concentration of valence electrons should be at least about five for each titanium atom and the resulting alloy should be one phase and homogeneous. The required concentrations for alloying additions are accurate to within about plus or minus 20 percent of the values calculated on this basis. To attain homogeneity, the usual techniques of metallurgy such as quenching, remelting, annealing, should be employed. Since titanium atoms and all atoms of the alloying additions participate in the primary cell anode reaction, it is possible to devise a variety of anodes with a variety of electrochemical properties.

Titanium alloys passivated according to the principles of this invention have exceptional stability as primary cell electrodes at elevated temperatures. To illustrate this discovery various primary cell anodes were placed in 14 molar. potassium hydroxide and corrosion rates. were in an otherwiseidentical cell;

s ove-ma measured 'by hydrogen evolution. -Results were as follows:

etched in a saturated aqueoussolutionbf potassiumhydroxide containing 0.25 M. of potassium tartrate.

Table IV At 80i20 F. At 165:1:5" F.

Anode Gasslng Open Cir- Gasstng Open 01:

IE/s te, o e. 2 ctult Vol- IE/rate. c uit Vola-. aevs. aagevs. y S CE y SCE Amalgamatedzinc 0.11 --1.66 29 1.13 Tltanlum 0. 31 -l. 55 93 1. 63 Titanium-30 weight p denum 0. 005 1. 05 1. 2 -1. 40 Titanium-14.9 weight percent vanadium 0. 3 -1. 28 0. 45 -1. 48 Titanium-40 'weight percent vana dlum 0. 045 1. 22 1. 8 1. 46 Titanium-35 weight percent molybdenum, fi-weight percent aluminunn. 0. 005 -1. 0. 42 1. 40

These datashow that for a titanium alloy anode containing, 14.9 percent vanadium, the gassing rate increases by only one-half when the temperature is increased from 80 F. to 165 F.; while,in contrast, the gassing rate for an amalgamated zinc anode (commonly used in commer cial primary cells) increases 170 times, andthe gassing rate for an unalloyed titanium anode increases '300 times, for the same-temperature increase.[ Furthermore, the gassing ratesat 165 FLfo'r the other titanium alloy anodes listed abov'e are less than one-tenth of the gassing rate for an amalgamated 'zinc anode,iand less than'one-fiftieth of the gassing rate for-anunalloyed titanium anode at the same temperature. In addition, the voltages 'for; the titanium=alloys increase by; at-least two-tenths -volt compared to a voltage increase of lessthan one-tenth volt for amalgamated zincor titaniumanodes.

The solidproducts formed onthe surface of some titanium alloy anodes during dis'charge .of. cells are, not current-blocking films as might be encountered on. pure and unalloy'e'd"titaniumjariodes infthe same electrolyte. For example, pure titanium anodes in primary cells having saturated KOH electrolytes'arid mercuric oxide cathodes polarizeafter a shortdrainage'ibeeaus'e' of the buildup of current-blocking' films; --Ti-3 0 Mo alloy anodes in the same-cells i deliver energy at practically constant voltage until the alloys are completely consumed by the T primary cell reactions;

Sintered titanium alloy anodes-provide higher currents and-higher closed-'circuit "voltage's than rolled anodes of equaPWeight, because the sintered anodeshave=*g'reater surface area per unit weight. In addition,'high opencircuit voltages are obtained, without additional 'an'ode pretreatment; upon immersion'of the sintered anodes in the cell electrolytes. The high voltages indicateactivesurfaces; which make sintered anodes still more advantageous over rolled metal anodes, many'of which must be 'cleaned and given an activation treatment before immersion in the cell. 'For example, a sintered Ti-27 Mo-10 Al anode had aninitial-open-circuit voltage of 1.540 volts vs. 'SCE in 14' M-KOH electrolyte,'while a solid Ti-27 Mo-1'0 Al anode had an initial open-circuitqvoltage'of -1.2'98 -volts 'Acellhaving-a Ti-'27 Mo-'10 Nb anode made and tested in connection with thisinvention illustrates typical'fresults disk about-- 0.455- inch in diameter and 0.01 inch thick,

weighir'rg:0'.15:'gram: The disk had been cold 1011mm the desiredthickness,stampedtoshape and anodically I The cell electrolyte was 0.5 cubic centimeter of a solution of 55 weight percent (14 M) potassium hydroxide in distilled water. I o

The cathode was made of 1.33 grams of compacted powder comprising 92 weight percent red mercuric oxide and 8 weight percent graphite.

The cell reached an equilibrium closed circuit voltage of 0.88.volt instantaneously on a load of about 10,000 ohms and. maintained this voltage within :1 percent throughout days of continuousdrain'at a temperature of 70 :2 F. An additional 70 days of-continuous drain was obtained before the cell voltage fell to 0.81 volt.

This cell illustrates the advantage of an extremely constant closed-circuit voltage at'constant temperature. The constancy of closed-circuit voltage is useful in a primary cell to provide a reference voltage while on drain. Such a cell is .useful for control instruments, electric clocks, transistor circuits, etc.

' This cellal'so has=the advantage that it can be discharged vat 32F. at about, 0.4: volt until, all the active materials having tita'niummetal anodes. To illustrate this, various titanium containing anodes were studied in saturated potassium hydroxide containing 0.25 molar potassium tartrate. Experimental results are listed in Table V below,

where the anode voltages are shown as measured against a reference SCE electrode.

Table V Closed Cir- Closed Cireuit Volcurt Vol- Polarizing tage of Cells Anode. tage vs. Current with Com- SCE at 5.0 Density, mercial maJln. .maJin. HgO Electrodes, Volts Both the titanium and the alloying addition, aluminum, beryllium, or boron, are'consumed during the cell reaction. This leads to extremely low equivalent weight. Therefore, small, light-weight high capacity primary cells may be made with anodes of these materials. Above certain maximum concentrations of alloying additions, howand, therefore, decreased shelf life of the primary cells using them. When the alloying addition is present in the anode in an amount below a certain weight percentage,

'8 'Liquid electrolytes arepreferred for those cells requiring high drainage rates. Gelled liquids or pastes are preferred for cells designed for low drainage rates. Gelling agents such as starch or glutens or others well known in the primary cell. art can be used.

Generally, the more concentrated the cell electrolyte,

ever, these alloys exhibit increased spontaneous corrosion,.. the greater is the watt'minute capacity of the cell fora given size.. Thus,- saturated solutions or saturated soluthe cell provides increased potential at high anode current 7 density without having significantly reduced shelf life. For example, the shelf life is best for beryllium contents less than 9 weight percent, aluminum contents less than sirable. The hydroxide concentration should be at least about .5 moles per liter, preferably at least about 11 moles per liter.

The cathode or depolarizer is preferably an oxygen yielding compound, such as mercuric oxide, the oxide or weight percent, and boron contents less than 10 weight percent. these alloying materials provide still higher currents at high closed circuit voltages. Such highly concentrated alloys give the higher currents and voltages with greater Anodes containing higher concentrations of efiiciency than the alloying elements alone and provide unusually high wattage per unit of weight or volume. Cells using such anodes are useful for various purposes requiring high drains for short periods, despite their Table VI Closed Cir- Polarizing Anode (Numbers refer to weight cult Volt- Gassing Current percent) age at 5.0 Rate, cc. Densty, max/in! H lday-lni Ina/in. vs. SCE

Ti- Mo -0. s4 0. 01a 6.0 Ti- Mo-5 Al 1. 10 0. 002 200 Other ternary additions to a binary alloy of titanium with a group V, VI, or VIII metal improve drainage properties when the ternary alloy is used as a primary cell anode. For example, 10 weight percent niobium or 10 weight percent vanadium added to a titanium-30 weight percent molybdenum alloy anode allows longer continuous drains at a more constant closed circuit. voltage and at larger anode current densities. Similar improvements with ternary additions of other elements in the periodic table to binary alloys of titanium with an element of group V, VI, or VIII are obtained where the two main principles of this invention are followedi (l) The total concentration of valence electrons should be at least about five for each titanium atom in the alloy, and (2) All elements should be in solid solution in one another, one phase, and homogeneous, in accordance with the well-known principles of metallurgy. For a nontransition element, the number of valence electrons is equal to the number of the periodic group in which the element appears.

ELECTROLYTES The preferred electrolytes for primary cells containing titanium alloy anodes are concentrated alkalies. They peroxide of silver, cupric or cuprous oxide, lead'peroxide, potassium permanganate or another alkaline permanganate, as is well known in the primary cell art.

A significant advantage of this invention is that where a suitable combination of cathode and electrolyte is chosen for stability, high'drain, small size, light weight, or some combination of these properties, then a titanium alloy anode can be constructed for the cathode-electrolyte combination that enhances these properties even further. For example, we have found Ti-30 Mo anodes in conjunction with alkaline electrolytes and mercuric oxide cathodes to be more stable, and thus to provide longer shelf life for the cells, than any other known anode with the same cathode-electrolyte combination. For best results the titanium alloy should be constructed with elements such that one or more of the reaction products is soluble in the chosen electrolyte, and the amounts of alloying additions to titanium should be such that the total concentration of valence electrons is at least about five for each titanium atom and the alloy anode is one phase.

The electrolytes are preferably made with potassium hydroxide or alkaline potassium salts. Most titanium alloys provide slightly higher open circuit voltage with saturated sodium hydroxide electrolytes than with saturated potassium hydroxide electrolytes. However, the titanium alloy anodes can be drained at larger current densities with the alkaline potassium electrolytes, and for most applications this makes the alkaline potassium electrolytes generally more desirable.

The concentration of a potassium hydroxide electrolyte affects the voltage characteristics, especially at high current densities. In the range from 11 molar to saturation, increasing concentration of the KOH increases the voltage at a given current density and provides useful output at higher current densities.

Zincate, tartrate, and aluminate additions to KOH of 11 M, and higher concentrations increase the voltage at a given current density and provide useful output at higher current densities.

Typical experiments illustrating the characteristics of various titanium alloy anode primary cells are shown in the data of Table VII. Data for titanium metal anodes are included for comparison. The anode voltages were measured in reference to a saturated calomel electrode. For actualacell operation, various well-known cathodes, such as mercuric oxide, nickel oxide, or. carbon-air electrode were used. The cell potentials in these cases may be readily calculated by known methods.

The extended drainages indicated in Table VII were taken at times varying from two hours to four weeks.

In Table VII, column 5 indicates whether current at the density shown may be drawn for several hours from .the primary cells at constant potential. Column 6 is a .critical current density at which the voltage of the primary cell abruptly decreases. Column 7 denotes shelf life as measured by corrosion of the anode, the'shelf life may be in the form of liquids, gelled liquids, or pastes. being inversely proportional to the gassing rate.

(A) .TYVITANIUM n'rn. 00.0000

Table .VII.-P r ope rties of primary cells comprising anodesof titanium and its alloys at ambient mom temperatures 6 m m m w m m m e 0 0 0 0 0. 0. 0 u w mm 0 0 0. 0, 0 w .0 n 0 a a. 0 mm 0 r 0 0 0 m .00 0 h m 0. u m r. r. 0 0 m 0 0 00 000. 0 w 8 a I 68 88.! w e I b eeh 0 m D 0 00001 0 .00 1 000 0 0 0 0 0 00 000 0 0B7. N 0m 0% mw u 100040.. D sootu 0.0000000 .00 m 0 0 .0 .2 0 02.0000 0.161 .ooranww woe A 20 31000N 00100000N3 m 5 %N N QNN AHWLZ. 0.N M0 0 w M MMM00 000 .00 n .0 m W 00000 0000 00 1 ism 0 000 000 s mmmm m m 00mm 0 0% mm 1 m s 1. w a R U H. 00 0 m m a m m m m n m n n 0 0000 0 F I n n m A I. E e .08. 5 O 0 T m nm w M. t 0 t S I H. m5 m I a 0 0 s 0 ,0000 00 1 m m a 0 0 0 T .00 I P w u A a 0 F n a. 0 Y Y 0 n T u n 0 .0 o 0 m. 1 Y n E Z. Y m m v m s Y n m E I .u u n M u n n w M 0 H 0 "0 u u E 0. .0 000 L 0. 0 .0 00000.0 0.00 0 05.00 520 L 0.. m T 8 m aaaaaa aaam tamma M MMMM A MM M U P w 0 0 0.000.: 00000 00; M 000 I: M N 00 00000 00000.00 "0 A m m m 000 n m 0.000. E 0. n 0 A 00 00000 W 00000000 0 0 0 000 a n 0000 T 0 m 0 00) m 00 00000 0 0 000000 T .00 000 n n 0000 0 0 n w m xmm r KK K K m KKKKKKKm mm m mmm mmm M m mmmm m m m tr F. u n .S u A .wjfinmwm. 0 MMMMMMMM M w MM MMMa rw MMMM m M0 0 0 0 .0 m 000 0 0 ..M 00000000 0 L OOON 00 0 0 M 0.N h L 0 0 0 3 W; A M 3 m 0 z b 0 0 n n u n n n s u u 0 owaw a HE 000 N 0 00000 0000 E 00 0 0 0 00 0 0 0 0 000 0 0000 0 8 e I I M w m m 0 00. R a dddMd .0000 N 00 0.0 0 0 00 000 P 0 000 K. 51 18 0M SS SSS m S SSSmS SSS-M m &-M I|\ m u .0 u m n m m C m u n n u u n n n u .o n s n m m s .0 0 r m m m n u n m m .E u n n 0 0 u u n n m B e u O u n w u n m 0 n 000). u N n n n n m m T 0 m mmmm m A m u u u 0 u n m I m 0 n 0000 u n u 0 0 w n n 0 11 u u 0 n newewe u 0 AA M u m u .UMH U 0 sqs .n :0 0000000? 0.... .0. 1]. 1.1 T 2 6 m .0. 000.000.0000. 0 0000 MM 6 O4 H 0. .0.0 0 0000000000. .0 1.000 mm TTTTM mm m TTTTTTTTT wfimfl mm 00000 00 0 0000000000 0 00 00 00 alkaline electrolyte and 11y of a single-phase, homogeneous alloy comprising at least atomic percent titanium with a met and tungsten, in solid the concentration of electrons outside 3, in which said ng of 29 percent molyb 18 percent chromium, 29 38 percent nickel, 24 percentniobium,

ent tungsten.

vanadium, chromium, coniobium, tantalum, solution, in which of the preceding ine the periodic table is atom.

1 Commercial Rem-Cru sheet titanium. 1 Numbers indicate weight percents oi alloyed elements.

What is claimed is: 1. A primary cell comprising a cathode, an alkaline electrolyte, and an anode that is an alloy consisting esleast 50 atomic percent titanium with at weight percent of a titanium passivating roup consisting of molybdenum, vanadiniobium, tantalum, and said anode being free from any king film .and in direct contact aid anode being conell by the flow ions 7 2. A primary cell having an alkaline electrolyte and an anode that is an alloy consisting essentially of at least 50 atomic percent titanium and a titanium passivating sentially of at least about 13 element of the g um, chromium, cobalt, nickel,

tungsten, the surface of substantial current bloc with said electrolyte, the alloy of s sumed in the discharge of said c therefrom to said electrolyte.

metal, said titanium passivating metal being present in electrolyte has an hydroxide concentration of at least about moles per liter.

5. A primary cell having an alkaline electi olyte and are in solid solution and in which the concentration of Y electrons outside of the preceding inert gas electronic core as describedin :-theperiodic table is at least about five for each titanium atom, said anode being in contact with an electrolyte consisting essentially of potassium hydroxide having a concentration of at least about 11 moles least 50 atomic percent titanium and at least about f weight percent molybdenum.

8. A primary cell having an anode consisting essentially of a single-phase, homogeneous alloy of at least 50 atomic percent titanium in which all elements present are in solid solution and in which the concentration of electrons outside of the preceding inert gas electronic core as described in the periodic table is at least about five for each titanium atom, said anode being in contact with an electrolyte consisting essentially of potassium hydroxide having aconcentration. within the range from substantial saturation to saturation plus a minor amount of solid phase.

9. A primary cell having an anode consisting essen tially of a single-phase, homogeneous alloy of at least 50 atomic percent titanium in which all elements present per liter.

10. A primary cell having an anode consisting essentially of a single-phase, homogeneous alloy of at least atomic percent titanium in which all elements present are in solid solution and in which the concentration of electrons outside of the preceding inert gas electronic core Qas'- described in the periodic table is at least about five --for each titanium atom, said anode being in contact with 15 an electrolyte consisting essentially of potassium hydroxide having a concentration of at least about 11 moles per liter, and a minor amount of a material selected from the group consisting of zincates, tartrates, and aidminates.

References Cited in the file of this patent UNITED STATES PATENTS Morrison May 11, 1915 Bomberger Jan. 14,1958

OTHER REFERENCES

Claims (1)

1. A PRIMARY CELL COMPRISING A CATHODE, AN ALKALINE ELECTROLYTE, AND AN ANODE THAT IS AN ALLOY CONSISTING ESSENTIALLY OF AT LEAST 50 ATOMIC PERCENT TITANIUM WITH AT LEAST ABOUT 13 WEIGHT PERCENT OF A TITANIUM PASSIVATING ELEMENT OF THE GROUP CONSISTING OF MOLYBDENUM, VANADIUM, CHROMIUM, COBALT, NICKEL, NIOBIUM, TANTALUM, AND TUNGSTEN, THE SURFACE OF SAID ANODE BEING FREE FROM ANY SUBSTANTIAL CURRENT BLOCKING FILM AND IN DIRECT CONTACT WITH SAID ELECTROLYTE, THE ALLOY OF SAID ANODE BEING CONSUMED IN THE DISCHARGE OF SAID CELL BY THE FLOW IONS THEREFROM TO SAID ELECTROLYTE.