WO2008032336A1 - Lead acid battery - Google Patents

Lead acid battery Download PDF

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Publication number
WO2008032336A1
WO2008032336A1 PCT/IN2007/000396 IN2007000396W WO2008032336A1 WO 2008032336 A1 WO2008032336 A1 WO 2008032336A1 IN 2007000396 W IN2007000396 W IN 2007000396W WO 2008032336 A1 WO2008032336 A1 WO 2008032336A1
Authority
WO
WIPO (PCT)
Prior art keywords
cell
plates
lead acid
acid battery
cells
Prior art date
Application number
PCT/IN2007/000396
Other languages
French (fr)
Inventor
Ajoy Datta
Original Assignee
Luminous Power Technologies Pvt Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Luminous Power Technologies Pvt Ltd filed Critical Luminous Power Technologies Pvt Ltd
Publication of WO2008032336A1 publication Critical patent/WO2008032336A1/en

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/06—Lead-acid accumulators
    • H01M10/12—Construction or manufacture
    • H01M10/128—Processes for forming or storing electrodes in the battery container
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/10—Primary casings; Jackets or wrappings
    • H01M50/102—Primary casings; Jackets or wrappings characterised by their shape or physical structure
    • H01M50/112—Monobloc comprising multiple compartments
    • H01M50/114—Monobloc comprising multiple compartments specially adapted for lead-acid cells
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/06—Lead-acid accumulators
    • H01M10/12—Construction or manufacture
    • H01M10/14—Assembling a group of electrodes or separators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/06—Lead-acid accumulators
    • H01M10/12—Construction or manufacture
    • H01M10/16—Suspending or supporting electrodes or groups of electrodes in the case
    • 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
    • H01M4/14—Electrodes for lead-acid accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/46—Separators, membranes or diaphragms characterised by their combination with electrodes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/50—Current conducting connections for cells or batteries
    • 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
    • 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
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Definitions

  • This invention in general relates to a lead acid battery and in particular relates to compression of a cell in a lead acid battery.
  • Lead acid batteries are the most widely used secondary batteries, extensively employed in applications like automobiles.
  • a battery has several cells electrically connected in parallel or series.
  • the basic construction of a cell comprises a positive plate, a negative plate, and an electrolyte.
  • Battery capacity is increased by electrically connecting a plurality of positive and negative plates in parallel to form a cell and, if required, subsequently electrically connecting a plurality of such cells in series.
  • the application for which the battery is being used determines the battery voltage and capacity i.e. the number of plates per cell, number of cells and the type of connections, i.e. series or parallel, to be made between the cells.
  • a separator is a physical insulation provided between two opposite polarity plates of a cell.
  • the separator provides simultaneous electronic insulation and ionic conduction.
  • the material forming the separator can be made from any of various-microporous, acid resistant materials having an affinity, i.e. high wettability for the liquid electrolyte. Examples of materials used as a separator are microporous rubber, porous plastic polymers and thin ion exchange resin membranes.
  • One function of the separator is to immobilize the electrolyte within the separator pores as in absorptive glass mats (AGM) used in sealed recombinant batteries.
  • AGM absorptive glass mats
  • Fig. 1 and IA provides an illustration of a lead acid battery of the prior art.
  • the battery comprises a container 100 comprising a plurality of compartments 102, a positive terminal 104 and a negative terminal 106.
  • the battery further comprises a plurality of cells comprising a first cell 121, a last cell 125 and one or more intermediate cells 123.
  • Each of the above cells comprises one or more positive plates 131, one or more negative plates 133 and one or more separator 135.
  • the separator 135 is placed between the positive plate 131 and the negative plate 133.
  • Each cell is placed in a compartment 102 of the container 100.
  • the positive plates 131 are electrically connected in parallel to each other to form a positive plate group and the negative plates 133 are electrically connected in parallel to each other to form a negative plate group.
  • the positive plate group of the first cell 121 is electrically connected to the positive terminal 104 while the negative plate group of the first cell is electrically connected to the positive plate group of the adjacent intermediate cell 123.
  • the negative plate group of the last cell 125 is electrically connected to the negative terminal 106 and the positive plate group of the last cell 125 is electrically connected to the negative plate group of the adjacent intermediate cell 123.
  • the positive or negative plate groups of intermediate cells 123 are electrically connected to each other and to the positive or negative plate group of the first cell 121 and the last cell 125 in either series or parallel connection or a combination of the two, as required.
  • the battery compartments 102 are separated by a wall.
  • the battery container 100 is typically made of acid resistant plastic material such as polypropylene or acrylonitrile-butadiene-styrene (ABS) and other materials known to the prior art.
  • ABS acrylonitrile-butadiene-styrene
  • For the proper functioning of the battery good contact between the separator 135 and adjacent plates is necessary. It is important that each separator 135 remains completely in contact with the entire surface area of its adjacent plates. The loss of contact between the plate surface and the separator 135 degrades battery performance.
  • the compression is achieved by ensuring snug support of the plate assembly in the battery container 100, using appropriately sized internal ribbing on the container walls and the use of shims placed outside the cell stack during assembly into the battery container 100.
  • a cell for a lead acid battery comprises one or more positive plates; one or more negative plates and one or more separator such that a separator is placed between one positive plate and one negative plate.
  • the plates, with the separators placed in between the plates, are compressed.
  • the plates of a cell are internally connected electrically as in the prior art.
  • the cell of the above embodiment can be compressed using compression plates and the compression can be to a predetermined uniform pressure.
  • a lead acid battery comprises cells of the previous embodiments.
  • a lead acid battery comprises a container of the prior art and a plurality of cells.
  • Each cell comprises one or more positive plate, one or more negative plate and one or more separator.
  • the separator is placed between the positive plate and the negative plate.
  • Each cell is individually compressed and placed in a compartment of the container.
  • the plates of a cell are internally connected electrically and the cells are interconnected electrically as in the prior art.
  • Fig. 1 provides an illustration of a battery container of a lead acid battery of prior art.
  • Fig IA provides an illustration of the top view of a lead acid battery of the prior art.
  • Fig. 2 provides an illustration of a cell in accordance with an embodiment of the present subject matter.
  • the subject matter describes, in one aspect, cells for a lead acid battery and a lead acid battery comprising such cells. In another aspect the subject matter describes a lead acid battery wherein individual cells in the battery are compressed.
  • Fig. 2 provides an illustration of a cell which is compressed in accordance with one embodiment of the present subject matter.
  • the figure illustrates a plurality of plates comprising a cell 200.
  • the cell 200 comprises a multiplicity of positive and negative plates interleaved with separators and placed between two acid resistant compression plates 202 and 204.
  • This assembly is compressed to a predetermined pressure and the two compression plates are locked in place.
  • the assembly can be compressed using techniques known to the prior art.
  • the compressed assembly can be locked in place using welded or bolted ties or using any other locking arrangement described in the prior art.
  • the above cell can be compressed to a predetermined pressure and locked in place.
  • This example describes a lead acid battery comprising cells of the embodiments of the previous examples.
  • One cell is inserted into one compartment of the container of the battery.
  • the plates of the cell and the cells can be electrically connected as in the prior art.
  • This embodiment relates to a lead acid battery comprising a container of the prior art and a plurality of cells.
  • Each cell comprises one or more positive plate, one or more negative plate and one or more separator.
  • the separator is placed between the positive plate and the negative plate.
  • Each cell is individually compressed and placed in a compartment of the container.
  • the plates of a cell are internally connected electrically and the cells are interconnected electrically as in the prior art.
  • This embodiment relates to the lead acid battery of the previous example wherein the individual cells are compressed to the same predetermined uniform pressure.
  • a lead acid battery comprises other steps such as curing and drying of the pasted plates, sealing the container, acid filling of the battery, etc. These processes are known to the prior art. The details of these steps are therefore not described herein.

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Secondary Cells (AREA)

Abstract

The subject matter described herein relates to cells for a lead acid battery, wherein individual cells are compressed. In another aspect, the subject matter described herein relates to a lead acid battery comprising the above cells.

Description

LEAD ACID BATTERY TECHNICAL FIELD
This invention in general relates to a lead acid battery and in particular relates to compression of a cell in a lead acid battery. BACKGROUND
Lead acid batteries are the most widely used secondary batteries, extensively employed in applications like automobiles. A battery has several cells electrically connected in parallel or series. The basic construction of a cell comprises a positive plate, a negative plate, and an electrolyte.
Battery capacity is increased by electrically connecting a plurality of positive and negative plates in parallel to form a cell and, if required, subsequently electrically connecting a plurality of such cells in series.
The application for which the battery is being used determines the battery voltage and capacity i.e. the number of plates per cell, number of cells and the type of connections, i.e. series or parallel, to be made between the cells.
Direct contact between the positive and negative plates would lead to an electrical short circuit. A separator is a physical insulation provided between two opposite polarity plates of a cell. The separator provides simultaneous electronic insulation and ionic conduction. The material forming the separator can be made from any of various-microporous, acid resistant materials having an affinity, i.e. high wettability for the liquid electrolyte. Examples of materials used as a separator are microporous rubber, porous plastic polymers and thin ion exchange resin membranes. One function of the separator is to immobilize the electrolyte within the separator pores as in absorptive glass mats (AGM) used in sealed recombinant batteries.
Fig. 1 and IA provides an illustration of a lead acid battery of the prior art. The battery comprises a container 100 comprising a plurality of compartments 102, a positive terminal 104 and a negative terminal 106. The battery further comprises a plurality of cells comprising a first cell 121, a last cell 125 and one or more intermediate cells 123. Each of the above cells comprises one or more positive plates 131, one or more negative plates 133 and one or more separator 135. The separator 135 is placed between the positive plate 131 and the negative plate 133. Each cell is placed in a compartment 102 of the container 100. The positive plates 131 are electrically connected in parallel to each other to form a positive plate group and the negative plates 133 are electrically connected in parallel to each other to form a negative plate group. The positive plate group of the first cell 121 is electrically connected to the positive terminal 104 while the negative plate group of the first cell is electrically connected to the positive plate group of the adjacent intermediate cell 123. The negative plate group of the last cell 125 is electrically connected to the negative terminal 106 and the positive plate group of the last cell 125 is electrically connected to the negative plate group of the adjacent intermediate cell 123. The positive or negative plate groups of intermediate cells 123 are electrically connected to each other and to the positive or negative plate group of the first cell 121 and the last cell 125 in either series or parallel connection or a combination of the two, as required.
The battery compartments 102 are separated by a wall. The battery container 100 is typically made of acid resistant plastic material such as polypropylene or acrylonitrile-butadiene-styrene (ABS) and other materials known to the prior art. For the proper functioning of the battery good contact between the separator 135 and adjacent plates is necessary. It is important that each separator 135 remains completely in contact with the entire surface area of its adjacent plates. The loss of contact between the plate surface and the separator 135 degrades battery performance.
In order to ensure proper contact between plate surfaces and separators 135 compression is necessary. Generally, the compression is achieved by ensuring snug support of the plate assembly in the battery container 100, using appropriately sized internal ribbing on the container walls and the use of shims placed outside the cell stack during assembly into the battery container 100.
However, during cell operation, gases produced due to the electrochemical reactions in the cell, apply pressure on the walls of the battery container 100 and cause bulging of the container walls. The bulging of the battery container walls results in non-uniform compression between the inner and outer cells. Even if the plates are initially supported by the container walls, any deformation of the walls would cause non uniform plate compression, degrading cell performance and life. ■
SUMMARY
This summary is provided to introduce a selection of embodiments in a simplified, form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
In an embodiment of the subject matter described herein, a cell for a lead acid battery is described. The cell comprises one or more positive plates; one or more negative plates and one or more separator such that a separator is placed between one positive plate and one negative plate. The plates, with the separators placed in between the plates, are compressed. The plates of a cell are internally connected electrically as in the prior art.
In other embodiments, the cell of the above embodiment can be compressed using compression plates and the compression can be to a predetermined uniform pressure.
In another embodiment, a lead acid battery comprises cells of the previous embodiments.
In yet another embodiment a lead acid battery is described. The battery comprises a container of the prior art and a plurality of cells. Each cell comprises one or more positive plate, one or more negative plate and one or more separator. The separator is placed between the positive plate and the negative plate. Each cell is individually compressed and placed in a compartment of the container. The plates of a cell are internally connected electrically and the cells are interconnected electrically as in the prior art.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 provides an illustration of a battery container of a lead acid battery of prior art.
Fig IA provides an illustration of the top view of a lead acid battery of the prior art. Fig. 2 provides an illustration of a cell in accordance with an embodiment of the present subject matter.
DETAILED DESCRIPTION
The subject matter describes, in one aspect, cells for a lead acid battery and a lead acid battery comprising such cells. In another aspect the subject matter describes a lead acid battery wherein individual cells in the battery are compressed.
Aspects of the lead acid battery described herein can be implemented in any number of different environments, and/or configurations that will be obvious to a person skilled in the art. Different embodiments of the battery are herein described in the context of the following exemplary method(s) only as examples and are not limiting to the scope of the described subject matter.
Example 1
Fig. 2 provides an illustration of a cell which is compressed in accordance with one embodiment of the present subject matter.
The figure illustrates a plurality of plates comprising a cell 200. As depicted in the figure, the cell 200 comprises a multiplicity of positive and negative plates interleaved with separators and placed between two acid resistant compression plates 202 and 204. This assembly is compressed to a predetermined pressure and the two compression plates are locked in place. The assembly can be compressed using techniques known to the prior art. The compressed assembly can be locked in place using welded or bolted ties or using any other locking arrangement described in the prior art. Example 2
The above cell can be compressed to a predetermined pressure and locked in place. :
Example 3
This example describes a lead acid battery comprising cells of the embodiments of the previous examples. One cell is inserted into one compartment of the container of the battery. The plates of the cell and the cells can be electrically connected as in the prior art.
Example 4
This embodiment relates to a lead acid battery comprising a container of the prior art and a plurality of cells. Each cell comprises one or more positive plate, one or more negative plate and one or more separator. The separator is placed between the positive plate and the negative plate. Each cell is individually compressed and placed in a compartment of the container. The plates of a cell are internally connected electrically and the cells are interconnected electrically as in the prior art.
Example 5
This embodiment relates to the lead acid battery of the previous example wherein the individual cells are compressed to the same predetermined uniform pressure.
It may be noted that the construction of a lead acid battery comprises other steps such as curing and drying of the pasted plates, sealing the container, acid filling of the battery, etc. These processes are known to the prior art. The details of these steps are therefore not described herein.
While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims

I/ We claim:
1. A cell for a lead acid battery comprising
one or more positive plates;
one or more negative plates; and
one or more separators;
such that a separator is placed between one positive plate and one negative plate and wherein said plates, with said separators placed in between said plates, are compressed.
2. A cell of claim 1 wherein said cell is compressed and locked using compression plates.
3. A cell of claim 2 wherein said cell is compressed to a predetermined uniform pressure.
4. A lead acid battery comprising cells of any of the preceding claims.
5. A lead acid battery comprising:
a container comprising:
a plurality of compartments;
a positive terminal; and
a negative terminal; and
a plurality of cells wherein each cell comprises:
one or more positive plates;
one or more negative plates; and
one or more separators such that a separator is placed between said positive plate and said negative plate and wherein said plates, with said separators placed in between said plates, are compressed, and one said cell is placed in one said compartment and said plurality of cells are electrically connected.
6. The lead acid battery of claim 5 wherein each said cell is compressed and locked using compression plates.
7. The lead acid battery of claim 6 wherein each said cell is compressed to a predetermined uniform pressure.
PCT/IN2007/000396 2006-09-13 2007-09-06 Lead acid battery WO2008032336A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN2027/DEL/2006 2006-09-13
IN2027DE2006 2006-09-13

Publications (1)

Publication Number Publication Date
WO2008032336A1 true WO2008032336A1 (en) 2008-03-20

Family

ID=38866721

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Application Number Title Priority Date Filing Date
PCT/IN2007/000396 WO2008032336A1 (en) 2006-09-13 2007-09-06 Lead acid battery

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WO (1) WO2008032336A1 (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE7002943U (en) * 1970-01-29 1971-07-08 Bosch Gmbh Robert GAS-PROOF LEAD ACCUMULATOR WITH PLASTIC CASE.
US4603093A (en) * 1983-02-03 1986-07-29 California Institute Of Technology Lead-acid battery
EP0584639A1 (en) * 1992-08-10 1994-03-02 Friedhelm Messmer Lead accumulator
EP0613201A1 (en) * 1993-02-17 1994-08-31 Electrosource, Inc. Battery plate compression cage assembly
US5618641A (en) * 1993-12-03 1997-04-08 Bipolar Power Corporation Bipolar battery construction
DE19738087A1 (en) * 1997-09-01 1999-03-04 Vb Autobatterie Gmbh Molded plastic case for electrical accumulator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE7002943U (en) * 1970-01-29 1971-07-08 Bosch Gmbh Robert GAS-PROOF LEAD ACCUMULATOR WITH PLASTIC CASE.
US4603093A (en) * 1983-02-03 1986-07-29 California Institute Of Technology Lead-acid battery
EP0584639A1 (en) * 1992-08-10 1994-03-02 Friedhelm Messmer Lead accumulator
EP0613201A1 (en) * 1993-02-17 1994-08-31 Electrosource, Inc. Battery plate compression cage assembly
US5618641A (en) * 1993-12-03 1997-04-08 Bipolar Power Corporation Bipolar battery construction
DE19738087A1 (en) * 1997-09-01 1999-03-04 Vb Autobatterie Gmbh Molded plastic case for electrical accumulator

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