US4460543A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparation of zinc powder for alkaline batteries by amalgamation of zinc powder
Assignee: Grillo Werke AG
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Filing: 1983-04-06
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Granted: 1984-07-17
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Expires: 2003-04-06
Abstract
Abstract Zinc powder containing mercury for alkaline batteries are prepared by reacting zinc powder with metallic mercury in the presence of amalgamation aids with agitation in a closed system, at a partial oxygen pressure of less than 100 mbar, while the volatile parts are continually exhausted, then raising the partial value of atmosphere air. Additional alloying elements can be added to reduce the gas development, by mixing zinc powder with metallic mercury in which is dissolved a part or the entire quantity of the required alloying elements.
Inventors
- 👤 Wolfgang Glaeser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 00:32
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/02; H01M4/36; H01M4/38; H01M4/42; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
82 words
A method for making zinc powder having a mercury content of 0.1-10% by weight for use in alkaline batteries which comprises: (a) stirring zinc powder with metallic mercury in the presence of an amalgamation aid at 20°-150° C. in a closed system at a partial pressure of oxygen below 100 mbar; (b) continuously removing excess amalgamation aid, water vapor and any volatile products formed from the system; and (c) gradually raising the partial pressure of oxygen in the system to atmospheric pressure.
Claim 2
Independent Claim
82 words
A method for making zinc powder having a mercury content of 0.1-10% by weight for use in alkaline batteries which comprises: (a) stirring zinc powder with metallic mercury in the presence of an amalgamation aid at 20°-150° C. in a closed system at a partial pressure of oxygen below 100 mbar; (b) continuously removing excess amalgamation aid, water vapor and any volatile products formed from the system; and (c) gradually raising the partial pressure of oxygen in the system to atmospheric pressure.
Claim 3
Dependent Claim
17 words
A method according to claim 1, wherein the temperature in steps (a) and (b) is 90° C.
Claim 4
Dependent Claim
21 words
A method according to claim 1, wherein the partial pressure of oxygen in steps (a) and (b) is below 20 mbar.
Claim 5
Dependent Claim
23 words
A method according to claim 1, wherein the amalgamation aid is a gas, dilute aqueous solution, dilute aqueous acid or dilute aqueous alkali.
Claim 6
Dependent Claim
18 words
A method according to claim 4, wherein the amalgamation aid is aqueous potassium, hydroxide, ammonia or carbonic acid.
Claim 7
Dependent Claim
31 words
A method according to claim 1, wherein pouring density of the zinc powder product is controlled by controlling the rate of increase in the partial pressure of oxygen during step (c).
Claim 8
Dependent Claim
24 words
A method according to claim 1, wherein zinc powder is mixed with metallic mercury having dissolved therein an alloying element to reduce gas development.
Claim 9
Dependent Claim
25 words
A method according to claim 4, wherein the zinc powder is mixed with metallic mercury containing dissolved therein an alloying element to reduce gas development.
Claim 10
Dependent Claim
19 words
A method according to claim 7, wherein the zinc powder reactant has incorporated therein part of the alloying element.
Claim 11
Dependent Claim
27 words
A method according to claim 7, wherein the alloying element is selected from the group consisting of gold, silver, tin, lead, cadium, indium, thallium, gallium and zinc.
References Cited (Backward Citations)
US3764338A
Cited
JPS54129322A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-17 | 1988-01-16 | 1988-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-17 | 1992-01-16 | 1992-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-17 | 1996-01-16 | 1996-07-17 | $7700.00 | Window Closed / Lapsed |