US3709459A - Mould for casting electrode grids for electric storage batteries - Google Patents
Mould for casting electrode grids for electric storage batteries Download PDFInfo
- Publication number
- US3709459A US3709459A US00090889A US3709459DA US3709459A US 3709459 A US3709459 A US 3709459A US 00090889 A US00090889 A US 00090889A US 3709459D A US3709459D A US 3709459DA US 3709459 A US3709459 A US 3709459A
- Authority
- US
- United States
- Prior art keywords
- mould
- silicon nitride
- backing plates
- casting
- electric storage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C3/00—Selection of compositions for coating the surfaces of moulds, cores, or patterns
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D25/00—Special casting characterised by the nature of the product
- B22D25/02—Special casting characterised by the nature of the product by its peculiarity of shape; of works of art
- B22D25/04—Casting metal electric battery plates or the like
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/64—Carriers or collectors
- H01M4/82—Multi-step processes for manufacturing carriers for lead-acid accumulators
- H01M4/84—Multi-step processes for manufacturing carriers for lead-acid accumulators involving casting
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Definitions
- the faces of the mould exposed to the melt comprise silicon nitride.
- the mould may comprise inserts of silicon nitride backed by backing plates of metal such as cast iron.
- a method of making such a mould includes pressing silicon powder between punches at least one of which has in it a form corresponding to the desired casting, and thereafter heating it in an atmosphere of nitrogen.
- An object of the invention is to enable lead or lead alloy battery plate grids to be cast without using mould dressing.
- a customary material for moulds for making such castings is meehanite cast iron, and the usual procedure is to spray the face of the mould with cork dust, generally about twice in each shift, in order to ensure filling of the mould. If such dressing is overlooked the mould is liable to fail to fill, and a large number of rejects may be obtained before the oversight is detected.
- silicon nitride has a low co-efficient of expansion and, for a ceramic, a relatively high thermal conductivity, resulting in high resistance to thermal shock, its thermal conductivity compared with metals is relatively low. This is of substantial advantage in casting thin lead castings such as battery plates which consist virtually of a network of wires and involve liquid metal traversing long narrow passages in order to reach all parts of the casting. Due, it is believed, to the low thermal conductivity of silicon nitride, it is found that the mould dressing can be omitted without producing a faulty casting that would result from this with a cast iron mould. V
- cork dressing assists the casting to part from the mould. It is found that the casting parts readily and clearly from the mould face of silicon nitride so that in this respect also the use of this material for the facing of the mould eliminates the need for mould dressing.
- Silicon nitride is sufficiently hard to stand up to the wear involved.
- the cooling of the mould may be increased by providing a layer of metal foil, (e.g. copper foil), of high conductivity, between the silicon nitride inserts and the backing plates.
- metal foil e.g. copper foil
- the mould includes a pair of silicon nitride facing plates 10 and 11 sandwiched between a pair of meehanite cast iron backing plates 16 and 17.
- Each facing plate is bevelled along two or more edges, and correspondingly bevelled clamping plates 24 and 25 are screwed, by screws 20 and 21 to the associated backing plate 16 or 17 to hold the facing plate in position.
- Each facing plate is provided with venting holes 12 and 13 and asbestos paper seatings 18 and 19 are interposed between the opposed faces of the backing plates 16 and 17 and facing plates 10 and 11.
- the usual alignment dowels 22 extend through the backing plates 16 and 17, in which they fit, and through the clamping plates 24 and 25 in which they have a clearance.
- the mould may be pre-heated.
- a mould for casting lead or lead alloy electrode grids for electric storage batteries in which the faces of the mould exposed to the melt comprise inserts of silicon nitride which are backed by backing plates 0 metal.
- a mould as claimed in claim 1 which includes a layer of metal foil, of high conductivity, between the silicon nitride inserts and the backing plates.
- a mould as claimed in claim 1 which includes asbestos paper between the silicon nitride inserts and the backing plates.
- a mould as claimed in claim 2 which includes asbestos paper between the silicon nitride inserts and the backing plates.
- a mould as claimed in claim 3 which includes asbestos paper between the silicon nitride inserts and the backing plates.
- a mould as claimed in claim 4 which includes asbestos paper between the silicon nitride inserts and the backing plates.
Abstract
A mould for casting lead or lead alloy electrode grids for electric storage batteries comprises backing plates of metal faced with inserts of silicon nitride exposed to the melt.
Description
United States Patent 1 Bushrod 51 Jan. 9, 1973 [54] MOULD FOR CASTING ELECTRODE GRIDS FOR ELECTRIC STORAGE BATTERIES [75] Inventor: Charles James Buslirod, Bramhall,
England [73] Assignee: Electric Power Storage Limited, Clifton Junction, Lancashire, En gland 221 Filed: Nov. 19, 1970 21 Appl. No.: 90,889
[30] Foreign Application Priority Data Primary Examiner-R. Spencer Annear Attorney-Watson, Cole, Grindle & Watson [57] ABSTRACT NOV. 21, Great Britain A mould f sting lea r lead al oy lectrode g ids for electric storage batteries comprises backing plates [52] US. Cl ..249/134, 164/138 of metal faced with inserts of silicon nitride exposed to [51] Int. Cl ..B22c 1/12 the melt i o [58] Field of Search ..164/138; 249/114, 134;
l17/5.1 8 Claims, 1 Drawing Figure I IHHHH H MOULD FOR CASTING ELECTRODE GRIDS FOR ELECTRIC STORAGE BATTERIES This invention relates to casting lead or lead alloy electrode grids for electric storage batteries.
According to the present invention in a method of casting lead or lead alloy electrode grids for electric storage batteries at least the faces of the mould exposed to the melt comprise silicon nitride. Thus the mould may comprise inserts of silicon nitride backed by backing plates of metal such as cast iron.
In one form of the invention a method of making such a mould includes pressing silicon powder between punches at least one of which has in it a form corresponding to the desired casting, and thereafter heating it in an atmosphere of nitrogen.
An object of the invention is to enable lead or lead alloy battery plate grids to be cast without using mould dressing. A customary material for moulds for making such castings is meehanite cast iron, and the usual procedure is to spray the face of the mould with cork dust, generally about twice in each shift, in order to ensure filling of the mould. If such dressing is overlooked the mould is liable to fail to fill, and a large number of rejects may be obtained before the oversight is detected.
Although silicon nitride has a low co-efficient of expansion and, for a ceramic, a relatively high thermal conductivity, resulting in high resistance to thermal shock, its thermal conductivity compared with metals is relatively low. This is of substantial advantage in casting thin lead castings such as battery plates which consist virtually of a network of wires and involve liquid metal traversing long narrow passages in order to reach all parts of the casting. Due, it is believed, to the low thermal conductivity of silicon nitride, it is found that the mould dressing can be omitted without producing a faulty casting that would result from this with a cast iron mould. V
In addition the cork dressing assists the casting to part from the mould. It is found that the casting parts readily and clearly from the mould face of silicon nitride so that in this respect also the use of this material for the facing of the mould eliminates the need for mould dressing.
Silicon nitride is sufficiently hard to stand up to the wear involved.
In some cases it may be found that the reduction of thermal conductivity is more than is required and the cooling of the casting may be unduly delayed. In this event the cooling of the mould may be increased by providing a layer of metal foil, (e.g. copper foil), of high conductivity, between the silicon nitride inserts and the backing plates.
The invention may be put into practice in various ways but one specific embodiment will be described by way of example with reference to the accompanying drawing which is a sectional elevation of a mould for casting lead or lead alloy electric storage battery plate grids.
The mould includes a pair of silicon nitride facing plates 10 and 11 sandwiched between a pair of meehanite cast iron backing plates 16 and 17. Each facing plate is bevelled along two or more edges, and correspondingly bevelled clamping plates 24 and 25 are screwed, by screws 20 and 21 to the associated backing plate 16 or 17 to hold the facing plate in position. Each facing plate is provided with venting holes 12 and 13 and asbestos paper seatings 18 and 19 are interposed between the opposed faces of the backing plates 16 and 17 and facing plates 10 and 11. The usual alignment dowels 22 extend through the backing plates 16 and 17, in which they fit, and through the clamping plates 24 and 25 in which they have a clearance.
If undue delay is experienced in the warming up of the mould when casting is started, the mould may be pre-heated.
It is believed that, perhaps by eliminating the need for dressing, the use of silicon nitride moulds gives improved surface finish to the castings, resulting in reduced corrosion rate of grids and improved overcharge life.
What we claim as our invention and desire to secure by Letters Patent is:
l. A mould for casting lead or lead alloy electrode grids for electric storage batteries in which the faces of the mould exposed to the melt comprise inserts of silicon nitride which are backed by backing plates 0 metal.
2. A mould as claimed in claim 1 in which the backing plates are of cast iron.
3. A mould as claimed in claim 1 which includes a layer of metal foil, of high conductivity, between the silicon nitride inserts and the backing plates.
4. A mould as claimed in claim 3 in which the metal foil is copper foil.
5. A mould as claimed in claim 1 which includes asbestos paper between the silicon nitride inserts and the backing plates.
6. A mould as claimed in claim 2 which includes asbestos paper between the silicon nitride inserts and the backing plates.
7. A mould as claimed in claim 3 which includes asbestos paper between the silicon nitride inserts and the backing plates.
8. A mould as claimed in claim 4 which includes asbestos paper between the silicon nitride inserts and the backing plates.
Claims (7)
- 2. A mould as claimed in claim 1 in which the backing plates are of cast iron.
- 3. A mould as claimed in claim 1 which includes a layer of metal foil, of high conductivity, between the silicon nitride inserts and the backing plates.
- 4. A mould as claimed in claim 3 in which the metal foil is copper foil.
- 5. A mould as claimed in claim 1 which includes asbestos paper between the silicon nitride inserts and the backing plates.
- 6. A mould as claimed in claim 2 which includes asbestos paper between the silicon nitride inserts and the backing plates.
- 7. A mould as claimed in claim 3 which includes asbestos paper between the silicon nitride inserts and the backing plates.
- 8. A mould as claimed in claim 4 which includes asbestos paper between the silicon nitride inserts and the backing plates.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB57066/69A GB1286330A (en) | 1969-11-21 | 1969-11-21 | Casting electric battery electrode grids |
Publications (1)
Publication Number | Publication Date |
---|---|
US3709459A true US3709459A (en) | 1973-01-09 |
Family
ID=10478271
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US00090889A Expired - Lifetime US3709459A (en) | 1969-11-21 | 1970-11-19 | Mould for casting electrode grids for electric storage batteries |
Country Status (4)
Country | Link |
---|---|
US (1) | US3709459A (en) |
JP (1) | JPS5017178B1 (en) |
FR (1) | FR2069572A5 (en) |
GB (1) | GB1286330A (en) |
Cited By (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4130157A (en) * | 1976-07-19 | 1978-12-19 | Westinghouse Electric Corp. | Silicon nitride (SI3 N4) leachable ceramic cores |
US4195002A (en) * | 1978-07-27 | 1980-03-25 | International Lead Zinc Research Organization, Inc. | Water-dispersible coatings containing boron nitride for steel casting dies |
US4546951A (en) * | 1982-08-19 | 1985-10-15 | Arbo Gereedschapsmakerij B.V. | Mould for encapsulating parts of elements into a plastic material |
US4614630A (en) * | 1984-04-02 | 1986-09-30 | Minnesota Mining And Manufacturing Co. | Mold having ceramic insert, method for injection molding using the same |
US4704079A (en) * | 1984-04-02 | 1987-11-03 | Minnesota Mining And Manufacturing Company | Mold having ceramic insert |
US4903753A (en) * | 1982-03-05 | 1990-02-27 | Varta Batterie Aktiengesellschaft | Casting technique for lead storage battery grids |
US5326652A (en) * | 1993-01-25 | 1994-07-05 | Micron Semiconductor, Inc. | Battery package and method using flexible polymer films having a deposited layer of an inorganic material |
USRE36843E (en) * | 1993-06-21 | 2000-08-29 | Micron Technology, Inc. | Polymer-lithium batteries and improved methods for manufacturing batteries |
US6782940B2 (en) | 2000-06-07 | 2004-08-31 | Romain L. Billiet | Method for rapid reproduction of molds and mold components |
US20050242964A1 (en) * | 1992-08-12 | 2005-11-03 | Tuttle John R | Miniature radio frequency transceiver |
US20070007345A1 (en) * | 1997-08-20 | 2007-01-11 | Tuttle Mark E | Electronic communication devices, methods of forming electrical communication devices, and communications methods |
US20110174459A1 (en) * | 2010-01-19 | 2011-07-21 | Water Gremlin Company | Mold assemblies including removable inserts and associated methods of use and manufacture |
US8802282B2 (en) | 2009-04-30 | 2014-08-12 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US9190654B2 (en) | 2004-01-02 | 2015-11-17 | Water Gremlin Company | Battery parts and associated systems and methods |
US9748551B2 (en) | 2011-06-29 | 2017-08-29 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US9954214B2 (en) | 2013-03-15 | 2018-04-24 | Water Gremlin Company | Systems and methods for manufacturing battery parts |
US11038156B2 (en) | 2018-12-07 | 2021-06-15 | Water Gremlin Company | Battery parts having solventless acid barriers and associated systems and methods |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
ATE9069T1 (en) * | 1981-05-29 | 1984-09-15 | Rosenthal Technik Ag | CERAMIC LINING FOR METAL MOLDS AND A PROCESS FOR THEIR MANUFACTURE. |
JPH03107008U (en) * | 1990-02-20 | 1991-11-05 |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2992127A (en) * | 1958-12-23 | 1961-07-11 | Texas Instruments Inc | Novel graphite articles and method of making |
US3286312A (en) * | 1965-03-29 | 1966-11-22 | Little Inc A | Refractory coated casting mold |
US3580328A (en) * | 1969-05-12 | 1971-05-25 | Gen Motors Corp | Mold for improved control of heat transfer in casting plate or strip products |
-
1969
- 1969-11-21 GB GB57066/69A patent/GB1286330A/en not_active Expired
-
1970
- 1970-11-17 FR FR7041207A patent/FR2069572A5/fr not_active Expired
- 1970-11-19 US US00090889A patent/US3709459A/en not_active Expired - Lifetime
- 1970-11-20 JP JP45102613A patent/JPS5017178B1/ja active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2992127A (en) * | 1958-12-23 | 1961-07-11 | Texas Instruments Inc | Novel graphite articles and method of making |
US3286312A (en) * | 1965-03-29 | 1966-11-22 | Little Inc A | Refractory coated casting mold |
US3580328A (en) * | 1969-05-12 | 1971-05-25 | Gen Motors Corp | Mold for improved control of heat transfer in casting plate or strip products |
Cited By (35)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4130157A (en) * | 1976-07-19 | 1978-12-19 | Westinghouse Electric Corp. | Silicon nitride (SI3 N4) leachable ceramic cores |
US4195002A (en) * | 1978-07-27 | 1980-03-25 | International Lead Zinc Research Organization, Inc. | Water-dispersible coatings containing boron nitride for steel casting dies |
US4903753A (en) * | 1982-03-05 | 1990-02-27 | Varta Batterie Aktiengesellschaft | Casting technique for lead storage battery grids |
US4546951A (en) * | 1982-08-19 | 1985-10-15 | Arbo Gereedschapsmakerij B.V. | Mould for encapsulating parts of elements into a plastic material |
US4614630A (en) * | 1984-04-02 | 1986-09-30 | Minnesota Mining And Manufacturing Co. | Mold having ceramic insert, method for injection molding using the same |
US4704079A (en) * | 1984-04-02 | 1987-11-03 | Minnesota Mining And Manufacturing Company | Mold having ceramic insert |
US8018340B2 (en) | 1992-08-12 | 2011-09-13 | Round Rock Research, Llc | System and method to track articles at a point of origin and at a point of destination using RFID |
US20070290863A1 (en) * | 1992-08-12 | 2007-12-20 | Tuttle John R | Radio Frequency Identification Device And Method |
US20050242964A1 (en) * | 1992-08-12 | 2005-11-03 | Tuttle John R | Miniature radio frequency transceiver |
US7746230B2 (en) | 1992-08-12 | 2010-06-29 | Round Rock Research, Llc | Radio frequency identification device and method |
US20070103316A1 (en) * | 1992-08-12 | 2007-05-10 | Tuttle John R | Radio frequency identification device and method |
US7583192B2 (en) | 1992-08-12 | 2009-09-01 | Keystone Technology Solutions, Llc | Radio frequency identification device and method |
USRE35746E (en) * | 1993-01-25 | 1998-03-17 | Micron Technology, Inc. | Battery package and method using flexible polymer films having a deposited layer of an inorganic material |
US5326652A (en) * | 1993-01-25 | 1994-07-05 | Micron Semiconductor, Inc. | Battery package and method using flexible polymer films having a deposited layer of an inorganic material |
USRE36843E (en) * | 1993-06-21 | 2000-08-29 | Micron Technology, Inc. | Polymer-lithium batteries and improved methods for manufacturing batteries |
US20070007345A1 (en) * | 1997-08-20 | 2007-01-11 | Tuttle Mark E | Electronic communication devices, methods of forming electrical communication devices, and communications methods |
US7839285B2 (en) | 1997-08-20 | 2010-11-23 | Round Rock Resarch, LLC | Electronic communication devices, methods of forming electrical communication devices, and communications methods |
US7948382B2 (en) | 1997-08-20 | 2011-05-24 | Round Rock Research, Llc | Electronic communication devices, methods of forming electrical communication devices, and communications methods |
US20070290862A1 (en) * | 1997-08-20 | 2007-12-20 | Tuttle Mark E | Electronic Communication Devices, Methods Of Forming Electrical Communication Devices, And Communications Methods |
US6782940B2 (en) | 2000-06-07 | 2004-08-31 | Romain L. Billiet | Method for rapid reproduction of molds and mold components |
US9190654B2 (en) | 2004-01-02 | 2015-11-17 | Water Gremlin Company | Battery parts and associated systems and methods |
US10283754B2 (en) | 2004-01-02 | 2019-05-07 | Water Gremlin Company | Battery parts and associated systems and methods |
US9935306B2 (en) | 2009-04-30 | 2018-04-03 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US9917293B2 (en) | 2009-04-30 | 2018-03-13 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US8802282B2 (en) | 2009-04-30 | 2014-08-12 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US10910625B2 (en) | 2009-04-30 | 2021-02-02 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US11942664B2 (en) | 2009-04-30 | 2024-03-26 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US20110174459A1 (en) * | 2010-01-19 | 2011-07-21 | Water Gremlin Company | Mold assemblies including removable inserts and associated methods of use and manufacture |
US9748551B2 (en) | 2011-06-29 | 2017-08-29 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US10181595B2 (en) | 2011-06-29 | 2019-01-15 | Water Gremlin Company | Battery parts having retaining and sealing features and associated methods of manufacture and use |
US9954214B2 (en) | 2013-03-15 | 2018-04-24 | Water Gremlin Company | Systems and methods for manufacturing battery parts |
US10217987B2 (en) | 2013-03-15 | 2019-02-26 | Water Gremlin Company | Systems and methods for manufacturing battery parts |
US11038156B2 (en) | 2018-12-07 | 2021-06-15 | Water Gremlin Company | Battery parts having solventless acid barriers and associated systems and methods |
US11283141B2 (en) | 2018-12-07 | 2022-03-22 | Water Gremlin Company | Battery parts having solventless acid barriers and associated systems and methods |
US11804640B2 (en) | 2018-12-07 | 2023-10-31 | Water Gremlin Company | Battery parts having solventless acid barriers and associated systems and methods |
Also Published As
Publication number | Publication date |
---|---|
FR2069572A5 (en) | 1971-09-03 |
JPS5017178B1 (en) | 1975-06-19 |
GB1286330A (en) | 1972-08-23 |
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