FR2485269A1 - SILVER OXIDE BATTERY DIVALENT, CONTAINING CADMIUM AND TELLURE COMPONENTS - Google Patents

Abstract

INVENTION RELATING TO BATTERIES. DIVALENT SILVER OXIDE BATTERY, OF A KIND CONTAINING A POSITIVE ELECTRODE MAINLY FORMED BY DIVALENT SILVER OXIDE THE STABILITY OF WHICH IS GREATLY INCREASED BY ADDING A CADMIUM COMPONENT AND A TELLURE COMPONENT AND AT LEAST ONE AUXILIARY COMPONENT CONTAINING A BODY CHOSEN FROM THE GROUP CONSTITUTED BY THALLIUM, MERCURY, LEAD, GERMANIUM, YTTRIUM, TIN, TUNGSTENE, LANTHAN, RARE EARTHS, ZINC, ALUMINUM AND SELENUM, EACH EITHER DIVALENT SILVER OXIDE, EITHER DIVALENT SILVER OXIDE, EITHER ALKALINE ELECTROLYTE OR BOTH. THE CONCENTRATION OF THE CADMIUM COMPONENT IS NOT LESS THAN 0.03 BY WEIGHT WHEN IT IS IN DIVALENT SILVER OXIDE AND NOT LESS THAN 0.01 GLITER IN ALKALINE ELECTROLYTE; THE TELLURE COMPONENT SHALL HAVE A CONCENTRATION OF NOT LESS THAN 0.01 BY WEIGHT IN DIVALENT SILVER OXIDE AND NOT LESS THAN 0.01 GLITER IN ALKALINE ELECTROLYTE; AND THE AUXILIARY COMPONENTS, A TOTAL CONCENTRATION NOT LESS THAN 0.01 BY WEIGHT IN DIVALENT SILVER OXIDE AND NOT LESS THAN 0.01 GLITER IN ALKALINE ELECTROLYTE. APPLICATION TO THE REALIZATION OF SILVER OXIDE BATTERIES.

Description

The present invention, concerning batteries, is more specifically

on perfectiomnnements

  to divalent silver oxide batteries,

  isolating the divalent silver oxide as the main constituent of the positive electrode of the cell. We know the classic alkaline batteries

  to silver in which the positive electrode of the

  the alkaline is mainly closed divalent silver dioxide and the negative electrode, mainly zinc

  or other sub - analogue. The silver oxide di -

  have a high oxygen content in comparison

  because of monovalent silver oxide and thus a stack

  use divalent silver oxide has a great capacity

  discharge city. Nevertheless, as silver oxide di-

  In the cell, the cell has poor stability and is gradually decomposed into monovalent silver oxide. During the storage of the battery structure, the oxygen produced inside the cell will increase the internal pressure in the cell. this one, so that the battery

  will deform or even, in extreme cases,

  tera. This decomposition of divalent silver oxide (also called "self-discharge") also means that the amount of divalent silver oxide available for

  the operation of the battery will decrease,

  singing the pile to produce the amount of electric current

  initially planned. In particular in

  alkaline products for long-term service,

  this phenomenon of self-discharge is an important problem.

  As. It is believed that the tendency to decompose that presents the divalent silver oxide in such a stack

  can be attributed to the great activity of the oxide of ar-

  divalent gent and the resulting reaction of oxy-

  of silver divalent with the alkaline electrolyte with which it is kept in direct contact. A method for avoiding these disadvantages, in which the surfaces of the divalent silver oxide particles are covered

-485269

  silver plating, is set forth in US Pat. No. 3,017,448. This process has made it possible to improve the shelf life.

  storage of a divalent silver oxide battery.

  As a criterion for the stability of the arsenic oxide

  divalent gent used in batteries, one can use the quantity called "rate of gasification" or "rate of formation of oxygen) '. This criterion is calculated by the volume of oxygen produced over a fixed period of time

  1 g of divalent silver oxide maintained in a

  40% aqueous solution of sodium hydroxide (sodium hydroxide) or potassium hydroxide (potassium hydroxide) at 400C. We will notice

  that these conditions are more severe than those in the

  what a divalent silver oxide battery works normally. Usually a silver oxide battery

  bivalent uses sodium hydroxide as the electrolyte.

  But, for applications requiring a strong electrical current from the beginning, these batteries must use for

  this is potassium hydroxide. Generally the oxide of arsenic

  classic bivalent gent presents less stability in

  potassium hydroxide in the presence of hydro-

sodium hydroxide.

  In seeking ways to stabilize a divalent silver oxide battery having divalent silver oxide in the positive electrode, experiments have been made to incorporate various additives into the cell. It was found that the addition of a source of lead and an aluminum source, either to the divalent silver electrode or to the alkaline electrolyte in the divalent silver oxide cell, could provide a large stability to divalent silver oxide. This discovery

  detailed in Japanese patent applications.

  JA-OS 9222/1981 and JA-OS 9966/1981.

  An object of the present invention is to provide a divalent silver oxide battery having a positive electrode formed primarily of oxide

  of divalent silver, in which the silver oxide divides

  slow will be characterized by significantly increased stability.

  In studying this issue closely, it has been found that when two cadmium-based and tellurium-based components are added to the divalent silver oxide, the alkaline electrolyte, or both, the stability of the divalent silver is significantly increased and the improved stability is not degraded even when using potassium hydroxide as the electrolyte for

the battery.

  We have yet discovered that a silver oxide

  divalent that includes a "cadmium component" and a "compound

  tellurium "can still have its improved stability * by adding the cadmium component and the tellurium component in conjunction with the addition of a

  or several auxiliary components containing ele-

  selected from the group consisting of thallium, mercury, lead, germanium, llytrium, tin, tungsten, lanthanum, rare earths, zinc, aluminum and selenium. These components

  auxiliaries can be incorporated into the oxide of ar-

  divalent gent, in the alkaline electrolyte or in both. Of the additive components used in the invention, some are readily soluble in the alkaline electrolyte, while others are only slightly soluble. In case, the stabilization of the

  divalent silver oxide battery according to this

  The reaction is carried out by adding the indicated components, in the required amounts, to the divalent silver oxide constituting the positive electrode, to the alkaline electrolyte or both. Like cadmium, thallium, mercury,

  tin and yttrium are not very soluble in the elec-

  alkaline trolyte, they are incorporated into this electro-

  lyte in the form of sludge or in the state of suspension.

  Moreover, like tellurium, lead, germanium,

  aluminum, zinc and selenium are easily

  lubles in the alkaline electrolyte, they dissolve under

  the form of ions when they are incorporated into the electro-

4 2485269

  lyte. Nevertheless, even in the case of an easy component

  Although only a small amount of dissolved component in the electrolyte is soluble in the alkaline electrolyte, this very small amount of dissolved component in the electrolyte will nevertheless play an important role in stabilizing the divalent silver oxide. . This means that the addition of such a component to the alkaline electrolyte, even if it is only slightly soluble in the bases, will show

  amply effective in stabilizing dietary silver oxide

worth.

  When adding the component to

  the divalent silver oxide, the latter will be advantageous

  of a type obtained, as is usually the case

  study, using a solution of silver nitrate, an oxidizing agent such as potassium persulfate and a caustic base. An almost similar result is achieved, however, by using a divalent silver oxide

  type produced by the process of the oxidation of halo-

  silver scythe or by the process of oxidation by

ozone.

  The inclusion of the cadmium component and the

  Said tellurium and / or the auxiliary component such as thalium or ltrium in the divalent silver oxide is advantageously effected by causing the reaction of an alkaline hydroxide, silver nitrate and an oxidizing agent, adding the cadmium component, the tellurium component and the auxiliary component to the divalent silver oxide produced in the resulting slurry (not yet

  filtered or dried), mixing them, then submitting

  both the resulting mixture to a filtration and a

  sication. This can be achieved by another route by previously desiccating divalent silver oxide, redispersing the dried divalent silver oxide in a dispersing agent and adding the cadmium component, the

  tellurium component and the auxiliary component

  resulting persion. The desired result can also be obtained by mechanically mixing silver oxide

  divalent in the dry state with the cadmium component

  tellurium and the auxiliary component. he is also

  possible to perform the inclusion by adding the

  cadmium, the tellurium component and the component

  xilar to a medium formed by a solution of silver nitrate, an alkaline solution, an oxidizing agent and water, medium which is treated to obtain divalent silver oxide. The inclusion is obtained as efficiently as described above by adding the cadmium, tellurium and auxiliary components to silver oxide granules

  divalent products during the preparation of the elec-

  divalent silver oxide positive trode for the cell and then compressing the resulting mixture

the positive electrode shape.

  When the components added to the divalent silver oxide battery are limited to cadmium and tellurium, the amount of cadmium component shall not be less than 0.03% by weight, calculated as cadmium metal, and that of the tellurium component

  not be less than 0,01% by weight calculated as such

  lure metal. Even though the present invention is carried out using amounts of additive components at their respective lower limits, the improvement in stack stability is remarkable in comparison

  with that provided by the classical technique does not

  as long as the only use of a cadmium component. In order to ob-

  hold the same degree of stability in the pile by the

  only cadmium, the amount of cadmium

  must be at least 0.3% in weight. This fact constitutes

  undoubtedly a clear indication that the addition of

  contemplated in the invention has a multiplied effect

  on improving the stability of the battery. Natural-

  In fact, the volume of oxygen produced inside the cell is more effectively reduced with the combined use of cadmium and tellurium. The effect of combined employment is, however, not absolutely obvious if both

  components are incorporated with tomato concentrations

  below their lower limits respectively

as indicated above.

  When the cadmium component and the tellurium component are added to the divalent silver oxide, the ratio of the amount of cadmium to that of tellurium should exceed 0.2 and even preferably 0.5. An excessive increase in the amount of tellurium relative to that of cadmium is undesirable because it destroys rather than improves the desired effects. The total of cadmium and tellurium to be added to the divalent oxide is advantageously maintained in

  below an upper limit of about 10% in weight.

  Increasing the amount of these elements would lower the purity of the divalent silver oxide and hence reduce the amount of electrical power generated. But if these components are used as inert fillers or as plating substances in divalent silver oxide when

  press the positive electrode of the battery, we can add them

  in quantities totaling more than 10% by weight. In this case, the added components

  do not degrade the stability of divalent silver oxide.

  Examples of the cadmium component which may advantageously be used in the invention are cadmium oxide, cadmium hydroxide, powdered cadmium metal, cadmium sulphide, cadmium sulphate,

  cadmium nitrate, cadmium stearate,

  cadmium mate, cadmium selenide and cadmium selenate. These cadmium-based components can be used singly or in combinations

  varied. Examples of the beneficial tellurium component

  Examples of the present invention include tellurium dioxide, tellurium trioxide, metal tellurium telluric acid, telluric acid, telluric acid alkaline salts, telluric acid alkaline salts and tellurates. These components to

  tellurium can be used singly or in combination

  varied. Compounds and alloys which contain both cadmium and tellurium, such as, for example, CdTeO 3, CdTeO and Od-Te powder alloy can also be used as additions. When adding components cad., Mitu. and tellurium to the alkaline electrolyte in the divalent silver oxide stack, the diea ntit eomp osmx acaium thus added advantageously exceeds 0 03 g / Xlitre although the effect of the addition of this compound does not become

  discernible only when the added amount goes up

  above 0.01 g / liter Nevertheless, I can be expected

  to increase this quantity beyond

  of 10 g / liter has some additional effect

  addition of the tellurium component becomes discernible.

  nable if the quantity of the added component increases

  above 0.01 g / liter For the effect of the addition is net, the tellurium component is advantageously added in an amount of not less than 0.02 g / liter, and

  preferably even 0.04 g / liter. When the concentration

  tion of the tellurium component thus added increases

  Finally, we note that the effect of the addition of this compound

  health declines. Therefore, the amount of the component

  must be kept below 5.0 g / liter.

  It is also possible to add one of the cadmium and tellurium components to the divalent silver oxide and the other to the alkaline electrolyte. In addition, one of the two components could be added only, either

  with divalent silver oxide, either with the alkaline electrolyte

  lin, and the other, partly to the divalent silver oxide and partly to the alkaline electrolyte. It is also allowed to add both components in part to the oxide

  of divalent silver and partly to the alkaline electrolyte.

  When one of the cadmium and tellurium components is added only to the divalent silver oxide and the other

  alkaline electrolyte alone, the lower limits

  res quantities of these elements so added are?

  equal to the lower limits of the quantities of

  when added solely to the oxide of arsenic

  divalent gent or alkaline electrolyte. When the

  The cadmium component is added in part to the arsenic oxide

  divalent and partly to the alkaline electrolyte, the

  amount of this component incorporated in the oxide of

  divalent gent must exceed 0.01% by weight and that in

  the alkaline electrode must exceed 0.02 g / liter.

  When the cadmium component, the component

  tellurium and the auxiliary component are incorporated

  In the case of divalent silver oxide, the amount of cadmium component must exceed 0.03% by weight as metal cadmium, that of the tellurium component must exceed 0.01% by weight as tellurium metal and that of the auxiliary component must exceed 0 , 01% by weight. The addition of

  auxiliary component such as thallium contributes

  the improvement of the stability of the battery

the divalent silver oxide.

  The upper limit of the total amount of the cadmium, tellurium and auxiliary components added to the divalent silver oxide is advantageously limited to the vicinity of 10% by weight. If the total exceeds this upper limit, the added components lower the purity of the divalent silver oxide and therefore decrease the amount of electrical current that can

  be produced by the battery. If auxiliary components

  As long as thallium is added beyond their upper limits of 3% by weight for each, their surplus quantities do not bring any additional effect.

  as we can see. Nevertheless, where these

  Auxiliary agents are used as inert charges when pressing the positive electrode of the cell, the total amount of cadmium, tellurium and auxiliary components may exceed 10% by weight similarly to the use of cadmium and tellurium components as inert charges . In this case, an increase in the total beyond the upper limit of 10o by weight is not likely

  not degrade the stability of the divalent agent oxide.

  As well as the cadmium component and the

  In the case of tellurium, auxiliary components such as thallium, lead, germanium, mercury, lytrium, tin, tungsten, lanthanum and rare earth elements can be used in the form of oxides,

  metals, salts and intermetallic compounds.

  When adding the cadmium components, such as

  lure and auxiliary to the alkaline electrolyte, their ef-

  fetuses begin to occur when the amounts of cadmium and tellurium each exceed 0.01 g / liter and the total of the amount of auxiliary components exceeds 0.01 g / liter. We can not expect that

  the effects of these components increase visi-

  if the total of their quantities exceeds 10g / liter.

  When cadmium and thallium, tin, yttrium and other auxiliaries that are slightly soluble in alkali are added to the electrolyte, the particle size of these substances does not exceed

  advantageously not the number of meshes 60.

  According to one possibility, cadmium and tellurium components and auxiliary components such as

  thallium may be added in part to the oxide of ar-

  divalent and partly to the alkaline electrolyte.

  In the single figure annexed, we see the

  schematic presentation of a device that can be used

  used to determine the stability of a divalent silver oxide battery. In the examples of embodiment cited below, the device of the figure was used to measure the gasification rate of the stack with divalent silver oxide, the device including a graduated glass tube 1, an alkaline electrolyte 2 , a sample of 1 gram of divalent silver oxide 3, a bath 4 to

  constant temperature and hot water 5 to 40 C.

EXAMPLE 1

  In 1000 cm3 of deionized water, 100 g of dry divalent silver oxide, synthesized from silver nitrate and potassium persulfate in a solution

  alkaline, were dispersed by stirring. In the

  The resulting persion, cadmium oxide as a cadmium source and a tellurium dioxide as a tellurium source, was added in various amounts shown in Table I and stirred for 10 minutes.

  The resulting mixture was then filtered and dried. Separate-

  In a 40% (by weight) aqueous potassium hydroxide solution as an electrolyte for a cell, cadmium oxide as a cadmium source was added and tellurium dioxide as a tellurium source with the various amounts indicated in Table I and they have been perfectly dispersed or dissolved. In

  the resulting solution, the divalent silver oxide mentioned

  Born above was allowed to stand for 240 hours at 40 ° C. The volume of gas produced during this rest has

  measured to evaluate oxygen formation. The re-

The results are shown in Table I.

TABILEAU I

  Oxide content Hydroxide content Divalent potassium silver content in

Exp. (% by weight) (g / liter)

(gTltre) "cation

n Cd Te Cd Te l / g-

2 h)

1 - - 627

2 - 0.30 - - 950

3 0.50 - - - 264

4 0.01 0.005 - - 291

0.03 0.01 - - 205

6 0.10 0.10 - - 98

7 0.03 0.10 - - 65

8 0.60 0.29 - - 54

9 2.50 2.47 - - 48

10.0 5.80 - - 45

11 0.30 - - 0.20 63

12 - - 0.01 0.01 320

13 - - 0.03 0.02 198

  TAEIOAU-I sui-teeur in the form of money divaleni; Cd T3e 0.20 0.20 0, 01 0.03 0.30 0.05 0.01 0.01 0.10 0.10 Content of potassium hydroxide X, 3Te

0705 0.05

0 to 0) 05

0.30 0.10

I 0 0750

3.0 1.0

9.5 1.5

0.50 0.20

0.50 =

0.50

0.02 0.02

0.30 0.02 0.10 0.10

  Experiments 1 to 3 were experiments

  those comparatives in which we did not use the

  cadmium and tellurium, either in the divalent silver oxide

  slow, either in the electrolyte. Experience n 4 incor-

  both cadmium and tellurium in the divalent silver oxide with amounts falling below the lower limits specified in the invention and therefore without having sufficient influence on the production of the gaso. Experiments 5 to 26 have summer of

  examples of demonstration of the invention and

  both cadmium and tellurium in the cell.

  divalent silver oxide as specified in the

  No. 5 in which cadmium and tellurium are used with amounts corresponding to their respective lower limits according to the invention of 0.3% and 0.01% gave better results than the experiment.

  No. 3 which used cadmium with the amount of 0.50%.

Exp. not

17

22

Rate

gazéifi-

cation

-S '/ g

3t, '' 1 A

  This contrast demonstrates the multiplied effect of addi-

  tion of the two components cadmium and tellurium. The experiences

  Nos. 6 to 10 were useful and favorable examples of the invention, with volumes of gas produced during a 240-hour rest, always below

  cm3 per gram. Among them, experiment no.

  poring both cadmium and tellurium with

  higher than those required, showed significantly better results than those

  experience 9. This clearly indicates that the ad-

  two elements exceeding the limit

  greater than 10% does not bring any additional effect.

  Experiment No. 11 was a demonstration example incorporating cadmium into divalent silver oxide and tellurium in the electrolyte. Experiments 12 to 19

  are examples of demonstration in which we

  corpore both cadmium and tellurium in the elec-

  trolyte. Examples 20 to 26 are exemplary embodiments in which cadmium and tellurium are partially incorporated in the divalent silver oxide and partially in the electrolyte. All these examples have

  provided equally favorable results.

* EXAMPLE 2

  In ooo1000 cm3 of deionized water, 100 g of oxide

  of divalent dry silver synthesized in the same way as

  in Example 1 were dispersed by stirring.

  In the resulting dispersion, Cd (OH) 2 as a source of cadmium, TeO2 as a source of tellurium and PbO, T1l203, GeO2 and HgO respectively as sources of lead, thallium, germanium and mercury were added in the indicated quantities in Table II as aqueous dispersions and stirred for minutes. The resulting mixture was then filtered and dried. The dried mixture obtained in this way was tested for stability in a 40% (by weight) aqueous solution of potassium hydroxide. The volume of gas produced during the 240 hours of the mixture lying in the solution was measured. Silver oxide was studied and the solution was measured. The divalent silver oxide has been studied to determine the content. The results are indicated

TABLE II

additional components

in Table II.

  Content of divalent silver oxide (% by weight) Cd Te Pb Tl

- - 0,50 -

- - - 0.50

  0.03 0.03 0.03 0.03 0.10 0.10 0.30 0.30 0.30 0.30 0.30 3.0, 0 3.0 1.0 0.01 0.01 0.01 0.01 0.01 0.05 0.05 0.10 0.10 0.10 0.10 0.10 3'o 2.0 2.0 0, 50 0.01 0.01

- U, U

0.05 -

- 0.05

0.10 -

- 0.10

  0.05 3.0 2.5 0.05 1.0 2.5 0.30 Exordence # 27 to 30 such comparative studies not containing but incorporating only Ge

gaseous if

cation

(4tú1 / g -

jI 240 h)

- - 299

- - 386

0.50 - 495

- 0.50 281

- - 157

- - 130

0.01 - 149

- 0.01 133

- - 65

- - 49

- - 17

_ - 7

0.10 - 13

- 0.11 9

_- 8

- - 5

- -.14

- - 4

_ _ 6

have been experienced

cadmium and tellurium,

of Pb, Tl, Ge and Hg.

  Experiments Nos. 31 to 34, which incorporated cadmium

  cadmium and tellurium in corresponding quantities.

  at the respective lower limits according to the

  which also included Pb, Tl, Ge and Hg, each

  0.01% yielded somewhat better results than Example 5 of Example 1 which Exp. No. 28 33 38 43 -

248 P69

  did not incorporate any of the auxiliary components. The former

  35 to 41 were examples of realizations incorporating cadmium and tellurium and either? b or

  other auxiliary components with small quantities

  significantly larger. In comparison with the results of experiment 7, those of experiments 57 to 41 clearly indicate the obvious effects of the addition of Pb, Tl, Ge and Mg. Experiments 42 to 45 are exemplary embodiments incorporating cadmium and

  tellurium and either Pb or other auxiliary components

  with slightly larger quantities and impli-

  therefore a very low rate of gasification

cation.

EXAMPLE 3

  Divalent silver oxide was washed with water

  synthesized in the same manner as in Example 1.

  In water washed divalent silver oxide and cadmium,

  tellurium, lead and germanium added to it

  in the various amounts indicated in Table III were shaken. The resulting mixture was filtered and dried. Separately, in an aqueous solution of potassium hydroxide at 40% (by weight), cadmium, tellurium,

  thallium and mercury have been included in the

  variables listed in Table III so as to obtain

  an electrolyte. The dry mixture obtained above was allowed to stand in the electrolyte at 40 ° C. for 240 hours. The volume of gas produced during the rest during these 240 hours was measured. The divalent silver oxide and the alkaline electrolyte have been studied for

  the content of the additive components. The components

  In the present case, the terms CdO, TeO2, NGeO2, T1203 and HgO were used. The results are

represented in Table III.

  Content of divalent silver oxide (ó by weight) Tl H_ Lb

- - 0.1

0.1 -. -

0.05 0.05

- - 0.05

- 0C1 -

- 0.05

0.1 - -

O, i l Ge 0.05 0.05 0.1

TABLE III

  Content of potassium hydroxide (g / liter) Cd O, 0.3 0.3 0.3. 0.3 0.3 0.3 0.3 0.3 Te T1

- 021

- 0,1

- 0,1

0.1 -

0.1 0.1

0.1 0.1

0.1.

0.1 -

0.1 0.1

0.1 -

  H-Pb 0.1 0.1 0.1 0e1 0 l., Ge 0.1 0.1c

0.1 0.05 0.05 0905 0.05

  Gasification rate (Al / g 240h) i, .5 l 5 1 $ 8 i Exp. n0 Cd 0.3 0.3 0.3 0.3 0.3 0.3 Te 0.1 0.1 0, 1 0.1 0, 1 0.1, 0.1 0.157 0.3 0.1

0,, 05 OeO5,;, L t i;

, -

  e. t In the test experiments, we used

  cadmium and tellurium with their respective quantities

  3% by weight and 0.1% by weight to be added to the divalent silver oxide, and 0.3g / liter and 0.1g / liter to be added to the electrolyte. , while the quantities of the components T1, Hg, Pb and

  Ge have been used in various combinations. We always

  days achieved good results in all the experi-

  these tests. The results show that these components

  are also effective, whether they are added to the oxy-

  of divalent silver or electrolyte.

EXAMPLE 4

  Dival silver oxide synthesized in the same manner as in Example 1 was washed with water. In water the washed divalent silver oxide and Y 2 O 3, SnO 2, WO 3, La 2 O 3, CeO 2, Sm 2 O 3 and ZnO used in the form of aqueous dispersions as sources of yttrium,

  tin, tungsten, lanthanum, cerium, sama-

  and zinc, and added to it according to the quantities

  various items shown in Table IV, were shaken

  for 10 minutes. The resulting mixture was then filtered

  very dry. We tried the dry mixture as to its stability.

  in a 40% (by weight) aqueous potassium hydroxide solution at 40 ° C. for 240 hours. We measured

  the volume of gas produced during the rest. Arsenic oxide

  divalent gent has been studied as to the content of

  additives. The results are those indicated in

grade IV.

TABLE IV

  Content of divalent silver oxide (% by weight) Cd Te Y Sn W Ce Ce Sm Rate

of

zéifi-

cation (n4 / g) Zn 240h 0.50

0.01 0.01

0.01 -

0.01 -

0.01 -

0.05 -

0.05 -

0.05 -

0.10 0.10

0.10 -

0, 10 -

0.10 -

0.50 -

1.0 0.50

2.0 - 3.0 -

- - - - 379

0.50 - - - - - 351

- - 0.50 - - 480

- - - 0.50 317

- - 153

0.01 - - - - 165

- 0.01 - - - 177

- -. - 0.005 0.005 175

- - 0.05 - - - 50

- - - 0.05 - - 56

- - 0.05 61

- _ _ - - 15

0.10 - - - - - 26

- - 0.05 - - 0.05 22

- - - - 0,10 - 14

- - - 0.30 - - 7

0.50 - - - 0.50 - 6

1.0 - 1.0 - - - 5

3.0 - 3.0 - - - 5

  Experiments Nos. 58 to 61 are comparative experiments in which no cadmium was used

  tellurium, but in which we incorporated inde-

  Y, Sn and Zn. Experiments Nos. 62 to 65, which in-

  cluait cadmium and tellurium in amounts corresponding to their respective lower limits according to the invention and which further included Y, Sn, W, etc., each with an amount of about 0.01%, provided results clearly better than Experiment # 5 in Example 1 which did not incorporate any of the other selected components such as Y and Sn. Examples Nos. 66 to 72 are exemplary embodiments incorporating Exp. No. 62 67 7o 72 0.03 0.03 0.03 0.03 0.10 0.10 0.10 0.30 0.30 0.30 0.30 1.0 3.0.0.0 _ _

  cadmium and tellurium and yttrium and other

  auxiliary substances in slightly more

  large. In combination with the results of the experi-

  No. 7, those of experiments Nos. 69 to 72 clearly indicate

  the obvious effects of the addition of Y, Sn, la, etc. Experiments 73 to 76 are examples of

  realization incorporating cadmium and tellurium and

  very auxiliary components in even larger quantities. the results of these tests indicate that the surplus addition of these components does not bring about

additional improvement.

EXEMPTION 5

  The divalent silver oxide was synthesized by the reaction of silver nitrate with potassium persulfate in alkaline solution. In the synthesis, a

  silver nitrate solution used as a raw material

  was slightly acidified with nitric acid

  than. In this solution we added cadmium and

  tellurium in the form of oxides in varying amounts

  shown in Table V and a variable number (none

  test experience) of the component group

  Yttrium, tin and tungsten and samarium, which has been added in the form of oxides with the various amounts also indicated in the table.

  V, have been dissolved or dispersed there. The solution or

  resulting prsion was used for the synthesis of

  the divalent silver oxide. the oxide samples

  divalent gent obtained in the various experiments were studied as to the rate of gasification. the results are shown in Table V.

TABLE V

  Content of divalent silver oxide (% by weight) Exp. Gasification No. Cd Te Y Sn W Sm l. 20 h)

77 0.28 0.12 - - - 67

78 0.32 0.10 0.12 - - - 14

79 0.20 0.10 - 0.09 - - 24

0.30 0.11 - - 0.10 - 23

81 0.32 0.12 - - - 0.13 17

  It will be noted that according to the indications in this table that if cadmium and tellurium are incorporated after formation of divalent silver oxide or if they are incorporated before the formation, the results are almost identical to those obtained in experiments no. 69 to

72 of Table IV.

  When the test was conducted to determine the rate of gasification by causing the samples to stand in 40% aqueous sodium hydroxide solution at 400 ° C. for 240 hours, the results were almost the same as those shown in FIG.

table above.

EXAMPLE 6

  In 1000 cm3 of deionized water, 100 g of oxide

  of divalent dry silver synthesized in the same way as

  in Example 1 were completely dispersed by stirring. In the resulting dispersion, Cd (OH) 2 as a source of cadmium, the tellurium powder metal as a source of tellurium and auxiliary components including Y203

  and Al203 respectively as a source of yttrium and aluminum.

  minium, as well as tin metal powder and selenium metal powder as sources of tin and selenium were added in the various quantities indicated

  in Table VI and intimately mixed. The resulting mixture

  both was filtered and dried. Separately, in a 40% aqueous solution (by weight) of potassium hydroxide, intended to serve as an electrolyte in a cell, CdO, TeO 2, Y 2 O 3, 1203 SeO 2 O, La 2 O 3, ZnO and SnO 2 were added in the amounts The resulting basic solution, the dry mixture mentioned above was allowed to stand for 240 hours and examined to determine its rate of gasification. The

  The results are shown in Table VI.

TABLE VI

  Content of divalent silver oxide (% by weight) Cd Te 0.3 0.3 0.3 0.3 0.3 0.3 0.1 0.1 0.1 0.1 0.1 0.1 0.1 oe y NN my o03 Y 0.01 Sn005 Oe005 n NM A1 0.1 Se 0.005 la 0.1 A1 Hy Cd content Te 0.5 0.5 0.5 0.5 0.5 0.5 0, 1 0.1 0.1 potassium hydroxide M / liter rate gasification (Mw / g 240 h) Y 0.01 0.005 Y 1.0 Se 0.1 Al 0.01 Al Se

0.05 0.05

Zn Sn

0.005 0.005

Sn

0.5 0.5

  o Exp. ## EQU1 ##% o Divalent silver oxide content (% by weight) Cd Te

- 0.1 Y - -

0.3

- 0.1 Y - -

0.3

- 0.1 Y -

0.3

0.3 - - Sn -

0.1

0.3 - - Sn -

0.1 0 ', 1

0.3 - - Sn -

  0.1 TABLE VI (cont.) Content of potassium hydroxide (g / liter) Cd Te

0.01 - - - -

0.05 - - - -

- 0.01 - - -

- 0.04 - - -

  Gasification rate (.t4l / g 240 h) Exp. no We see by the values provided by the table

  VI when adding cadmium and tellurium to

  of divalent silver and yttrium and other

  auxiliaries to the electrolyte, as in the experiments

  these Nos. 82 to 85 and 86 and 87 give better results than when the addition of asiliary components is omitted as in the. experience nO 4- and when such

  Auxiliary components are added. larger quantity

  As in Experiments 86 and 87, stability is even better. Experiments Nos. 88 and 89 are exemplary embodiments incorporating cadmium in

  electrolyte and adding tellurium9 to the electro-

  lyte, either with divalent silver oxide and the experience

  No. 90 was a comparative experiment omitting the incor-

  poration of auxiliary components. Comparing their results clearly shows that such examples

  in accordance with the present invention provides

  better results. Examples Nos. 93 to 95 and 96 to 98 are exemplary embodiments incorporating cadmium or tellurium in corresponding quantities.

  at their respective lower limits according to the invention.

  In experiments Nos. 93 to 95, tellurium and yttrium were added in equal amounts. In the experience

  No. 93 no cadmium was incorporated, while the former

  period 94, cadmium was incorporated with a concentration

  0.01 g / liter. The comparison of these results shows that the addition of cadmium already shows its effect,

  even when the amount of cadmium added is very small.

  corn. In experiments n 96 to 98, we added cadres

  milum and tin in equal amounts. In experiment no. 96 there is no tellurium incorporated, while in experiment no. 97 -on has incorporated tellurium with a

  concentration of 0.01 g / liter. Comparison of the results

  states that the addition of tellurium manifests its effect

* when the amount of tellurium added is very small.

  In the test experiments indicated above, electricity

  The trolyte used was potassium hydroxide. When repeated experiments with sodium hydroxide

  the results were quite similar.

EXAMPLE 7

  In 1000 cc of deionized water, 100 grams of dry divalent silver oxide synthesized in the same manner as described in Example 1 were perfectly dispersed by stirring. In the resulting dispersion,

  a different source of cadmium with a varying amount

  Table VII and mixed thoroughly.

  The resulting mixture was filtered and dried. In an election

  trolyte which was an aqueous solution of potassium hydroxide in some experiments and an aqueous solution of sodium hydroxide in other experiments,

  a source of various tellurium has been added with the quantity

  variable in Table VII to determine the rate of gasification. the results are shown in

Table VII.

TABLE VII

  Source of Cd Exp. for addition to AgO Cd content (wt%) in AgO Te source for addition to the electrolyte Te content in the base (g / liter) Kind of alkaline solution Degree of azeification fUl /. 240 h) 99 Od (OH) 2 Cd metal powder 101 CdS 102 Cd (N3) 103 OdO 104 Cd (OH) 2 O, 30 l. ## STR2 ## TeO 2 TeO 2 H 6 TeO 6 TeO 2 O powder, 0.20 0.10 0.05 0.10 0.10 KOH, 4% NaOH, and 0.1% by weight. 99 to 104 are examples

  implementation using various sources of

  mium and various sources of tellurium. The values of

  The table above shows that the results are

  tically the same, although they vary slightly with

  the kind of sources of cadmium and tellurium used.

EXAMPLE 8

  From the divalent silver oxide synthesized from the

  same way as indicated in Example 1 was washed with water.

  In water, washed divalent silver oxide and

  The Cd, Te, Tl, Pb, Y and Sn salts added to it in the various amounts indicated in Table VIII were stirred. The resulting mixture was filtered and dried. The dried silver oxide sample thus obtained

  was molded in a pill machine under a pressure

  4 tons / cm 2, so as to produce tablets weighing 0.5 g each and measuring 10 mm in diameter. The

  tablets had a thickness of about 1 min. Separate-

  in a 40% (by weight) aqueous solution of hy-

  Potassium droxide provided as an electrolyte in a cell, Cd (OH) 2, sodium tellurate, T1203, PbO, Y2O3 and SnO2 were added in amounts calculated to give the various concentrations shown in Table VIII. In the resulting alkaline solution, the

  tablets mentioned above are not required to

  240 hours, then tested for the rate of gasification

  cation. In the test device, the tablets were placed to prevent any of them from falling on a

  other. The results are shown in Table VIII.

:, 4V) 8269

TALAU -II

TABLE VIII

  Oxy content: divalent silver (ó by weight) jxp. n Cd Te T1 Potassium hydroxide content (e / liter) Gasification rate $ 1 / g. 240h) Cd Te Ti 108

0.3 0.1 -

0.3 0.1 0.1

0.3 001 0.1 -

109 2.0 0.5 -

- - -

111 - -

112 0.3 - -

113 5.0 1.0 1.0

0.5 0.5

- S0

0.1

0.5 0.2

0.5 0.2

0.5 0.2

0.5 0.2

, 0 1.0

, 0 1.0

Pb On 0.5 0.5 Pb Oe5 0.5 0.5 Y 1.0

114 10.0 2.0 2.0

, 2.0 2.0 2.0

  In general, the material of the positive electrode is molded into tablets at a pressure of the order of 4 tons / cm 2 and in the form of tablets

  set up in a stack. In this example,

  samples of divalent silver oxide. have been

  experienced in the gasification rate under conditions

  approximations of that of the reaction taking place

  in a real pile. Experiment No. 105 has been an experiment

  comparative experience that omitted the incorporation of

  additives. As the silver oxide crystals di-

  valent were exposed to solicitations during the

  molding, the rate of gasification obtained in this experiment

  test experience was superior to that of experience

  No. 1 using divalent silver oxide powder.

  Experiment No. 106 was an example incorporating only

  cadmium and tellurium, whereas experiment 107 incorporated thallium in addition to cadmium and m___ D.S

  tellurium. In these two test experiments, we recorded

  a higher rate of gasification than when the same samples were tested under

  their non-agglomerated powder form, because of the ef-

  constraint. Nevertheless, the result clearly indicates a clear effect of incorporation of the additive components in contrast to the results of Experiment No. 105. Experiments Nos. 108 and 109 are exemplary embodiments in which the number of

  additive components and their amounts have been increased.

  In these test experiments, gasification rates

  have been lowered correspondingly. Experiences

  these nO 110 and 111 are examples of realization in

  which the additive components have been incorporated only

  in the electrolyte. the results of these experiences

  These tests are similar to those obtained in ex-

  test runs in which the additive components have been incorporated into the divalent silver oxide. the

  Examples Nos. 113 and 114 are examples of

  using additive components in larger quantities.

  quantities. The result shows that the exaggerated addition of these components does not bring discernable improvement

by the effect of their addition.

REVEIMIC} Aions

  1. Stack with divalent silver oxide, containing

  an alkaline electrolyte and including a positive electrode formed mainly of divalent silver oxide, characterized in that a cadmium component and a component

  tellurium are contained in at least the oxide of ar-

  divalent gent or in at least the alkaline electrolyte.

  2. Battery with divalent silver oxide according to

  claim 1, characterized in that said component

  cadmium is included in the said divalent silver oxide

  slow, with a concentration of not less than 0.03% by weight. 3. Battery with divalent silver oxide according to

  claim 1, characterized in that said component

  cadmium is incorporated in said alkaline electrolyte

  flax, with a concentration of not less than 0.03 g / liter.

  The divalent silver oxide battery according to claim 1, characterized in that said cadmium component is included in said divalent silver oxide with a concentration of not less than 0.01% by weight and incorporated in said alkaline electrolyte. with a concentration of not less than 0.02 g / liter 5. Divalent silver oxide battery

  claim 1, characterized in that said component

  tellurium is included in said divalent silver oxide

  slow with a concentration of not less than 0.01% by weight. 6. Battery with divalent silver oxide according to

  claim 1, characterized in that said component

  tellurium is incorporated in said alkaline electrolyte

  flax with a concentration of not less than 0.02 g / liter.

  7o Divalent Silver Oxide Battery

  claim 1, characterized in that said component

  tellurium is contained in said di-silver oxide

  are not less than 0.02% in

  weight and in said alkaline electrolyte with a concentration

  not less than 0.02 g / liter.

  8. Divalent silver oxide battery according to

  claim 1, characterized in that said component

  health cadmium has been added to the suspended state audit

alkaline electrolyte.

  9. Battery with divalent silver oxide

  claim 1, characterized in that the incorporation

  said cadmium component and said tellurium component

  in said divalent silver oxide is obtained in

  making a divalent silver oxide sludge

  an alkaline hydroxide, silver nitrate and

  oxidizing agent, by the addition of said components to the

  said mud and by their mixture in it.

  10. Divalent silver oxide battery

  claim 1, characterized in that the incorporation

  said cadmium component and said tellurium component

  in said divalent silver oxide is obtained in

  divalent silver oxide by reaction of an alkaline hydroxide, silver nitrate and an oxidizing agent, by

  drying said divalent silver oxide by the dispersion

  resuspend the dried divalent silver oxide in a dispersion fluid and then add the said

  components to the resulting dispersion.

  11. Silver oxide battery according to claim

  cation 1, characterized in that the incorporation of said cadmium component and said tellurium component in said divalent silver oxide is obtained by producing the divalent silver oxide by reaction of an alkaline hydroxide, silver nitrate and an oxidizing agent, by drying the divalent silver oxide produced and then mixing said components mechanically with the oxide

dried divalent silver.

  12o divalent silver oxide battery according to claim 1, characterized in that the formation reaction of the divalent silver oxide using a solution of silver nitrate, an alkaline solution, an oxidizing agent and the water is made with said cadmium component and said tellurium component incorporated

? 635,269

  ji in the raw materials used for the training of

the divalent silver oxide.

  13. A divalent silver oxide battery according to claim 1, characterized in that said cadmium component and said tellurium component, when included in said divalent silver oxide, are included with such quantities as ratio of cadmium to tellurium not less than 092 14. Silver oxide stack diTalen; according to claim 13, characterized in that said report

is greater than 0.5.

  15. Silver oxide battery according to claim

  cation 1, characterized in that the total quantities of cadmium component and tellurium component contained in said divalent silver oxide is not greater than

at 10% by weight.

  16. Divalent silver oxide battery

  claim 1, characterized in that said component

  cadmium is at least one member selected from the group consisting of cadmium oxide, cadmium hydroxide, powdery cadmium metal, cadmium sulfide, cadmium sulfate, cadmium nitrate, stearate,

  cadmium, cadmium formate and cadmium selenide.

  17o Divalent Silver Oxide Battery

  claim 1, characterized in that said -compo-

  health tellurium is at least one body chosen from the group

  consisting of tellurium dioxide, trioxide of

  lure, powdery tellurium metal, telluric acid, telluric acid, alkaline salts of telluric acid

  and the alkaline salts of telluric acid.

  18. Battery with divalent silver oxide

  claim 1, characterized in that said component

  cadmium and said tellurium component, when contained in said alkaline electrolyte, are included therein with respective concentrations of not less than 0.03 g / liter and not less than 0.01 g / liter 19. Battery divalent silver oxide

  claim 14, characterized in that said component

  cadmium is contained with a concentration in the range of 0.03 to 10 g / liter and said tellurium is in a concentration within the range of

ranging from 0.04 to 5.0 g / liter.

  20. Stack with divalent silver oxide

  claim 8, characterized in that said component

  cadmium, when added to the alkaline electrolyte

  flax, has a particle size not greater than

at a mesh size of 60.

  21. Divalent silver oxide battery containing

  an alkaline electrolyte and having a positive electrode

  mainly composed of divalent silver oxide,

  characterized in that a cadmium component and a composition

  tellurium and at least one auxiliary component selected from the group consisting of thallium, mercury, lead, germanium, yttrium, tin, tungsten, lanthanum, rare earth elements, zinc, nickel, aluminum and selenium are contained in at least the divalent silver oxide or in at least the alkaline electrolyte. 22. Battery with divalent silver oxide

  claim 21, characterized in that said component

  cadmium is contained in said di-silver oxide

  are at a concentration of not less than 0.03% by weight. 23. Divalent silver oxide battery

  claim 21, characterized in that said component

  cadmium is contained in said alkaline electrolyte

  with a concentration of not less than 0.01 g / liter.

  24. Divalent silver oxide battery

  claim 21, characterized in that said component

  cadmium is contained in said di-silver oxide

  are not less than 0.03% in

  weight and in said alkaline electrolyte with a concentration

  not less than 0.01 g / liter.

  25. The divalent silver oxide battery as claimed in claim 21, characterized in that said tellurium component is contained in said divalent silver oxide with a concentration of not less than 0.01% by weight. 26. Divalent silver oxide battery

  claim 21, characterized in that said component

  tellurium is contained in said alkaline electrolyte

  with a concentration of not less than 0.01 g / liter.

  27. Divalent silver oxide battery

  claim 21, characterized in that said component

  tellurium is contained in said di-silver oxide

  are at a concentration of not less than 0.01% by weight and in said alkaline electrolyte with a

  concentration not less than 0.01 g / liter.

  28. The divalent silver oxide battery according to claim 21, characterized in that at least one

  auxiliary component is contained in said oxide of

  divalent gent with a concentration not lower than

0.01% by weight.

  29. The divalent silver oxide battery according to claim 21, characterized in that at least

  an auxiliary component is contained in said electro-

  alkaline lyte with a concentration not lower than

0.01 g / liter.

  30. The divalent silver oxide battery according to claim 21, characterized in that at least one

  auxiliary component is contained in said oxide of

  divalent gent with a concentration of not less than 0.01% by weight and in said alkaline electrolyte with

  a concentration of not less than 0.01 g / liter.

  31. divalent silver oxide battery according to claim 21, characterized in that the total of the amount of cadmium component, tellurium component and at least one auxiliary component contained in said

  divalent silver oxide does not exceed 10% by weight.

  32. Battery with divalent silver oxide according to

  claim 21, characterized in that said component

  cadmium and said at least one auxiliary component containing a member selected from the group consisting of thallium, mercury, tin and yttrium are added in the suspended state to said alkaline electrolyte. 33. Divalent silver oxide battery

  claim 21, characterized in that the incorpo-

  said cadmium component, said tellurium component

  and said at least one auxiliary component in said oxy-

  of divalent silver is produced by producing a divalent silver oxide sludge by the reaction of an alkali hydroxide, silver nitrate and an oxidizing agent, by adding said components to said slurry and by their mixture. 34. Divalent silver oxide battery

  claim 21, characterized in that the incorporation

  said cadmium component, said tellurium component and at least one said auxiliary component in said divalent silver oxide is obtained by producing divalent silver oxide by the reaction of an alkaline hydroxide, silver nitrate, and an oxidizing agent, by drying said divalent silver oxide, by redispersion of the dried divalent silver oxide in a dispersion fluid and then adding said components to the dispersion

resultant.

  35. Divalent silver oxide battery

  claim 21, characterized in that the incorporation

  said cadmium component, said tellurium component and at least one said auxiliary component in said divalent silver oxide is made by producing divalent silver oxide by the reaction of an alkaline hydroxide, silver nitrate and an oxidizing agent by drying the divalent silver oxide produced and then mixing

  mechanically said components with the dried divalent ar-gent oxide.

  36. The divalent silver oxide battery according to claim 21, characterized in that the reaction to the formation of divalent silver oxide using a solution of silver nitrate and an alkaline solutinn, an oxidizing agent and water is made with said cadmium component, said tellurium component and at least one said auxiliary component incorporated into the materials

  first for the formation of divalent silver oxide.

  37. Divalent silver oxide battery according to

  claim 21, characterized in that said component

  cadmium is at least one body chosen from the group

  consisting of cadmium oxide, cadmium hydroxide, -

  powdered cadmium metal, cadmium sulphide, cadmium sulphate, cadmium nitrate, cadmium stearate, cadmium formate and cadmium selenide. 38. Divalent silver oxide battery according to

  claim 21, characterized in that said component

  health tellurium is at least one body chosen from the group

  consisting of tellurium dioxide, trioxide of

  lure, the telluric metal powder, the telluric acid,

  telluric acid, the alkaline salts of telluric acid

  and the alkaline salts of telluric acid.

  39. Divalent silver oxide battery according to

  claim 33, characterized in that said component

  cadmium and said at least one auxiliary component, when added to the alkaline electrolyte, have a particle size not exceeding the number of

mesh 60.