MXPA00006494A - Electrochemical cell balance - Google Patents

Abstract

An electrochemical cell, such as a battery (10), having a large amount of electrolytic solution relative to the amount of manganese dioxide and/or zinc particles. The cathode (12) can have a weight ratio of manganese dioxide to electrolytic solution of from about 2.2 to about 2.9, and a weight ratio of zinc particles in the anode (14) to electrolytic solution can be from about 0.9 to about 1.25.

Description

BALANCE OF ELECTROCHEMICAL CELL DESCRIPTION OF THE INVENTION The invention relates to batteries. Batteries, such as alkaline batteries, are commonly used as sources of energy. In general, alkaline batteries have a cathode, an anode, a separator and an electrolytic solution. The cathode is typically formed of manganese dioxide, carbon particles and a binder. The anode can be formed from a gel that includes zinc particles. The separator is usu-to the entity placed between the cathode and the anode. The electrolyte solution, which is dispersed throughout the length of the battery, can be a hydroxide solution. The invention relates to batteries, such as alkaline batteries, which have a large amount of electrolytic solution relative to the amount of manganese dioxide and / or zinc particles. These batteries have good operating characteristics. For example, batteries can show high energy efficiency at a high discharge rate, such as a discharge speed equal to at least the capacity REF.121418 of the battery (in units of ampere-hours) discharged in one hour. The batteries may have various standard sizes in the industry, such as AA, AAA, AAAA, C or D. In one aspect, the invention features an alkaline battery having a cathode, an anode, an electrolytic solution and a separator placed between the cathode and the anode. The cathode includes manganese dioxide, and the anode includes zinc particles. The weight ratio of manganese dioxide to the electrolyte solution is from about 2.2 to about 2.9 - and the weight ratio of the zinc particles to the electrolyte solution is from about 0.9 to about 1.25. These proportions are based on the amount of electrolytic solution dispersed throughout the anode, the cathode and the separator. In still another aspect, the invention features an alkaline battery having a cathode, an anode, an electrolytic solution and a separator positioned between the cathode and the anode. The cathode includes manganese dioxide, and the anode includes zinc particles. The weight ratio of manganese dioxide to the electrolyte solution is from about 2.5 to about 2.9, and the weight ratio of the zinc particles to the electrolyte solution is from about 1.1 to about 1.25. In a further aspect, the invention features an alkaline battery having a cathode, an anode, an electrolytic solution and a separator positioned between the cathode and the anode. The cathode includes manganese dioxide, and the anode includes zinc particles. The weight ratio of manganese dioxide to the electrolyte solution is from about 2.5 to about 2.65, and the weight ratio of the zinc particles to the electrolyte solution is from about 0.9 to about 1.2. The invention also relates to AA alkaline batteries that give at least 150 pulses to discharge at 1 volt according to the photo test (described below), at least about 0.6 hours to discharge up to 1 volt according to the test continuous of 1 watt (described further below), at least about 1. 6 hours to discharge at 1 volt according to the pulsed test (described below) and / or at least about 1.5 hours to discharge at 1.1 volts according to the half-watt rm test (described below). The invention further relates to AAA alkaline batteries that give at least about 0.65 hours to discharge up to 1 volt, according to the continuous half-watt test (described below), at least about 0.35 hours to discharge up to 1 volt according to to the pulsed test (described below), at least about 0.4 hours to discharge at 1.1 volts according to the half-watt rm test (described below) and / or at least about 2 hours to discharge at 1.1 volts according to the one-quarter watt rm test (described later). The separator can include a non-membranous material, non-woven, and a second non-woven, non-woven material, placed along a surface of the first material. The separator may be devoid of a membrane layer or an adhesive layer placed between the non-membrane, non-membrane materials. A membrane material refers to a material having an average pore size of less than about 0.5 microns, while a nonmembranal material refers to a material having an average pore size of at least about 5 microns. The cathode may include manganese dioxide and non-synthetic, non-expanded graphite particles having an average particle size of at most about 20 microns as measured using a Sympatec HELIOS analyzer. For a given sample of graphite particles, the average particle size is the particle size for which half the volume of the sample has a smaller particle size. "Non-synthetic graphite particles" refers to graphite particles that are prepared without the use of an industrial or laboratory graphitization process. "Non-expanded graphite particles" refer to graphite particles that have not undergone industrial or laboratory expansion process. The cathode can have a porosity of about 21% up to about 28%. The porosity of the cathode corresponds to the relative volume of the cathode that is not picked up by the solid material, such as, for example, manganese dioxide, carbon particles and binder.

The anode can have a porosity of about 2 grams of zinc particles to about 2.45 grams of zinc particles per cubic centimeter of anode volume that is collected by the liquid or solid material. The batteries can be AA or AAA batteries that can show good results when tested according to the photo test, the continuous 1 watt test, the continuous half watt test, the pulsed test, the half watt rm test and / or the rm test of a quarter of a watt. These tests are described below. Other features and advantages of the invention will be apparent from the description of the preferred embodiments thereof and from the claims. Figure 1 is a cross-sectional view of a battery. Preferred batteries are alkaline batteries having a weight ratio of manganese dioxide to the electrolyte solution of about 2.2 to about 2.9 and a weight ratio of the zinc particles to the electrolyte solution of about 0.9 to about 1.25. In some embodiments, the weight ratio of manganese dioxide to the electrolyte solution is from about 2.5 to about 2.9, and the weight ratio of the zinc particles to the electrolyte solution is from about 1.1 to about 1.25. In other embodiments, the weight ratio of manganese dioxide to the electrolyte solution is from about 2.5 to about 2.65, and the weight ratio of the zinc particles to the electrolyte solution is from about 0.9 to about 1.2. These proportions by weight are based on the amount of the electrolytic solution dispersed throughout the cathode, the anode and the separator. With reference to Figure 1, a battery 10 having a cathode 12, an anode 14, a separator 16, an outer wall 18 which contacts the outer diameter of the cathode 12 and the insulating layer 26 is shown. The battery 10 includes in addition an anode manifold 20 which passes through a seal member 22 and into the anode 14. The upper end of the anode manifold 20 is connected to a negative end cap 24, which serves as the negative external terminal of the anode. battery 10. The layer 26 can be formed of an electrically non-conductive material, such as a heat-shrinkable plastic. In addition, an electrolyte solution is dispersed throughout the length of battery 10. Cathode 12 may include any of the standard forms of manganese dioxide used in battery cathodes. Distrors of such manganese dioxide include Kerr McGee, Co. , Broken Hill Proprietary, Chem Metals, Co. , Tosoh. Delta Manganese, Mitsui Chemicals and JMC. In certain embodiments, the cathode 12 can have from about 8.9 grams of manganese dioxide to about 9.8 grams of manganese dioxide. In these embodiments, the cathode 12 preferably includes from about 9.3 grams to about 9.8 grams of manganese dioxide, more preferably from about 9.4 grams to about 9.65 grams of manganese dioxide, and most preferably from about 9.45 grams to about 9. 6 grams of manganese dioxide. In other embodiments, the cathode 12 preferably has from about 4 grams to about 4.3 grams of manganese dioxide, more preferably from about 4.05 grams to about 4.25 grams of manganese dioxide, and more preferably from about 4.1 grams to about 4.2 grams of dioxide of manganese. Typically, cathode 12 also includes carbon particles. These carbon particles can be any of the standard carbon particles used in battery cathodes. The particle size is limited only by the dimensions of the cathode 12. These can be synthetic or non-synthetic, and can be expanded or not expanded. In certain modalities, the carbon particles are non-synthetic, non-expanded graphite particles. In these embodiments, the graphite particles preferably have an average particle size of less than about 20 microns, more preferably from about 2 microns to about 12 microns, and more preferably from about 5 microns to about 9 microns, as measured using an analyzer Sympatec HELIOS. The non-synthetic, unexpanded graphite particles can be obtained for example from Brazilian Nacional de Grafite (Itapecirica, MG Brasil).

The amount of carbon particles with the cathode 12 must be high enough to improve the conductivity of the cathode 12, while having minimal impact on the energy capacity of the battery 10. In some embodiments, the cathode 12 preferably includes about 4 weight percent to about 10 weight percent of carbon particles, more preferably from about 5 weight percent to about 9 weight percent of carbon particles, and more preferably from about 6 weight percent to about 8 weight percent. percent by weight of carbon particles. These percentages by weight correspond to when the electrolytic solution is not dispersed within the cathode 12. In some embodiments, the cathode 12 may also include a binder. Examples of binders for the cathode 12 include polyethylene powders, polyacrylamides, Portland cement and fluorocarbon resins, such as PVDF and PTFE. In certain embodiments, the cathode 12 includes a polyethylene binder sold under the tradename coathylene HA-1681 (Hoescht). When the cathode 12 includes a binder, the binder preferably constitutes less than about 1 weight percent of the cathode 12, more preferably from about 0.1 weight percent to about 0.5 weight percent of the cathode 12, and most preferably about 0.3 percent by weight of the cathode 12. These weight percentages correspond to when the electrolyte solution is not dispersed within the cathode 12. The cathode 12 may include other additives. Examples of these additives are described in U.S. Patent No. 5,342,712, which is incorporated by reference herein. In some embodiments, the cathode 12 preferably includes from about 0.2 weight percent to about 2 weight percent TiO2, more preferably 0.8 weight percent TiO2. The cathode 12 can be a single pellet of material. Alternatively, the cathode 12 can be formed from a number of cathode pellets that are stacked one on top of the other. In any case, the cathode pellets can be processed first by the mixture of manganese dioxide, carbon particles and optionally a binder. For embodiments in which more than one pellet is used, the mixture can be pressed to form the pellets. The pellet (s) are adjusted within the battery 10 using standard processes. For example, in one process, a core rod is placed in the central cavity of the battery 10, and a punch is then used to pressurize the pellet from the higher part. When this process is used, the interior of the wall 18 may have one or more vertical flanges that are spaced circumferentially around the wall 18. These ridges may help retain the cathode 12 in place within the battery 10. In the embodiments in which the cathode 12 is formed of a single pellet, the powder can be placed directly inside the battery 10. A retaining ring can be adjusted in place, and an extrusion rod can pass through the ring, densifying the powder and forming the cathode 12. In certain embodiments, a layer of the conductive material can be placed between the wall 18 and the cathode 12. This layer can be placed along the inner surface of the wall 18, along the length of the outer circumference of the cathode 12 or both. Typically, this conductive layer is formed of a carbonaceous material. Such materials include LB1000 (Timcal), Eccocoat 257 (.R. Grace &Co.), Electrodag 109 (Acheson Industries, Inc.), Electrodag 112 (Acheson) and EB005 (Acheson). The methods of applying the conductive layer are described for example in Canadian Patent No. 1,263,697, which is incorporated by reference herein. When the cathode 12 is placed inside the battery 10 by a pressing process, the provision of a conductive layer between the wall 18 and the cathode 12 can decrease the amount of pressure used to place the pellet (s) inside the battery 10. In this way, the porosity of the cathode 12 can be made relatively high without causing the or pellets are crushed or form grietase However, if the porosity of cathode 12 is too low, can supply an insufficient amount of electrolyte within the cathode 12, reducing the efficiency of battery 10. therefore, the cathode 12 should have a porosity of from about 21% to about 28%, more preferably from about 25% to about 27%, and more preferably about 26%. The anode 14 can be formed from any of the standard zinc particle materials used in battery anodes. Frequently, the anode 14 is formed of a zinc gel that includes the zinc particles, a gelling agent and minor amounts of additives, such as gasification inhibitors. In addition, a portion of the electrolyte solution is dispersed throughout the anode 14. In some embodiments, the anode 14 preferably includes from about 3.7 grams to about 4.25 grams of zinc particles, more preferably from about 3.8 grams to about 4.15 grams. of zinc particles, and more preferably from about 3.9 grams to about 4.05 grams of zinc particles. In other embodiments, the anode 14 preferably includes from about 1.5 grams to about 1.9 grams of zinc particles, more preferably from about 1.55 grams to about 1.85 grams of zinc particles, and most preferably from about 1.65 grams to about 1.75 grams of zinc particles. zinc particles. In certain embodiments, the anode 14 preferably includes from about 64 weight percent to about 76 weight percent zinc particles, more preferably from about 66 weight percent to about 74 weight percent zinc particles, and most preferably from about 68 weight percent to about 72 weight percent zinc particles. These percentages by weight correspond to when the electrolytic solution is dispersed along the entire anode 14. If the porosity of the anode 14 is too high, the energy capacity of the battery 10 is reduced, but, if the porosity of the anode 14 is too low can supply an insufficient amount of electrolyte within the anode 14. thus, in certain embodiments, anode 14 preferably includes from about 2 grams of zinc particles to about 2.45 grams of zinc particles per cubic centimeter of anode more preferably a porosity of about 2.1 grams of zinc particles to about 2.35 grams of zinc particles per cubic centimeter of anode, and most preferably a porosity of about 2.15 grams of zinc particles to about 2.3 grams of zinc particles per cubic centimeter of anode.

Typically, the anode 14 includes one or more gelling agents. Such gelling agents include polyacrylic acids, grafted starch materials, polyacrylic acid salts, polyacrylates, carboxymethylcellulose or combinations thereof. Examples of such polyacrylic acids are Carbopol 940 (B.F. Goodrich) and Polygel 4P (3V), and an example of a grafted starch material is Waterlock A221 (Grain Processing Corporation, Muscatine, IA). An example of a salt of a polyacrylic acid is CL1.5 (Allied Colloids). In some embodiments, the anode 14 preferably includes about 0.2 weight percent to about 1 weight percent total gelling agent, more preferably from about 0.4 weight percent to about 0.7 weight percent total gelling agent, and more preferably from about 0.5 weight percent to about 0.6 weight percent of total gelling agent. These percentages by weight correspond to when the electrolytic solution is dispersed throughout the anode 14. The anode 14 can also include gasification inhibitors. These gasification inhibitors can be inorganic materials, such as bismuth, tin, lead and indium. Alternatively, the gasification inhibitors can be organic compounds, such as phosphate esters, ionic surfactants or nonionic surfactants. Examples of ionic surfactants are described, for example, in U.S. Patent No. 4,777,100, which is incorporated by reference herein. The separator 16 can have any of the conventional designs for battery separators. In some embodiments, the separator 16 is formed of two layers of non-woven, non-membranous material, with one layer that is placed along one surface of the other. To minimize the volume of the separator 16 while providing an efficient battery, each layer of non-woven, non-woven material can have a basis weight of about 54 grams per square meter, a thickness of about 137.1 micrometers (5.4 mils) when it is dry and a thickness of approximately 254 μm (10 mils) when wet. In these embodiments, the separator preferably does not include a layer of membranous material or a layer of adhesive between the non-woven, non-membranous layers. In general, the layers may be substantially devoid of fillers, such as inorganic particles. In other embodiments, the separator 16 includes an outer layer of cellophane with a layer of nonwoven material. The separator 16 also includes an additional layer of nonwoven material. The cellophane layer may be adjacent to the cathode 12 or the anode 14. Preferably, the nonwoven material contains from about 78 weight percent to about 82 weight percent PVA and from about 18 weight percent to about 22 weight percent. Weight of rayon with a trace of a surfactant. Such non-woven materials are available from PDM under the tradename PA36. The electrolytic solution dispersed throughout the length of the battery 10 can be any of the conventional electrolytic solutions used in batteries. Typically, the electrolyte solution is an aqueous hydroxide solution. Such aqueous solutions of hydroxide include, for example, solutions of potassium hydroxide and solutions of sodium hydroxide. In some embodiments, the electrolyte solution is an aqueous solution of potassium hydroxide that includes from about 33 weight percent to about 38 weight percent potassium hydroxide. The amount of electrolytic solution dispersed throughout the cathode 12, the anode 14 and the separator 16, may be such that the weight ratio of manganese dioxide to the electrolyte solution and the zinc particles to the electrolytic solution, are within the ranges previously noted. In certain embodiments, the battery 10 preferably includes from about 3.4 grams to about 3.9 grams of electrolyte solution, more preferably from about 3.45 to about 3.65 grams of electrolyte solution, and most preferably from about 3.5 grams to about 3.6 grams of electrolyte solution. In other embodiments, the battery 10 preferably includes from 1.6 grams to about 1.9 grams of electrolyte solution, more preferably from about 1.65 grams to about 1.85 grams of electrolyte solution, and most preferably from about 1.7 grams to about 1.8 grams of electrolyte solution. The batteries can be AA or AAA batteries that show good results when tested according to the photo test, the continuous 1 watt test, the continuous half watt test, the pulsed test, the half watt rm test, and / o the continuous test of half a watt. These tests are described below. The battery 10 can be an AA battery or a battery that offers excellent performance according to the photo test (described below). For example, when discharging at 1 volt according to the photo test, the AA battery can give at least 150 pulses, at least about 175 pulses, at least about 185 pulses or at least about 200 pulses. When discharged at 0.8 volts according to the photo test, the AA battery can give at least 350 pulses, at least about 375 pulses, at least about 385 pulses or at least about 400 pulses. The battery 10 can be an AA battery that offers excellent performance according to the continuous 1 watt test (described below). For example, when discharging at 1 volt according to the continuous 1 watt test, the AA battery can give at least about 0.6 hours, at least about 0.65 hours, at least about 0.7 hours or at least about 0.75 hours. When discharging at 0.8 volts according to the continuous 1 watt test, the AA battery can give at least 0.95 hours, at least about 1 hour, at least about 1.05 hours or at least about 1.1 hours. The battery 10 can be an AA battery that offers excellent performance according to the pulsed test (described below). For example, when discharging at 1 volt according to the pulsed test, the AA battery can give at least about 1.6 hours, at least about 1.75 hours, at least about 2 hours or at least about 2.15 hours. When discharged at 0.8 volts according to the pulsed test, the AA battery can give at least 2.75 hours, at least about 3 hours, at least about 3.25 hours or at least about 3.3 hours. The battery 10 can be an AA battery that offers excellent performance according to the half-watt rm test (described below). For example, when discharging at 1.1 volts according to the half-watt rm test, the AA battery can give at least about 1.5 hours, at least about 2 hours, at least about 2.5 hours, or at least about 2.65 hours. When discharged at 0.9 volts according to the half-watt rm test, the AA battery can give at least 2.9 hours, at least about 3 hours, at least about 3.25 hours or at least about 3. hours. The battery 10 can be an AAA battery that offers excellent performance according to the continuous half-watt test (described below). For example, when discharging at 1 volt according to the continuous half-watt test, the AAA battery can give at least about 0.65 hours, at least about 0.7 hours, at least about 0.75 hours or at least about 0.8 hours. When it is discharged at 0.9 volts according to the continuous test of half a watt, AAA battery can give at least 0.9 hours, at least about 0.95 hours, at least about 1.0 hour or at least about 1.05 hours. The battery 10 can be an AAA battery that offers excellent performance according to the pulsed test (described below). For example, when discharging at 1 volt according to the pulsed test, the AAA battery can give at least about 0.35 hours, at least about 0.4 hours, at least about 0.45 hours or at least about 0.5 hours. When discharged at 0.9 volts according to the pulsed test, the AAA battery can give at least 0.65 hours, at least about 0.7 hours, at least about 0.75 hours or at least about 0.8 hours. The battery 10 can be an AAA battery that offers excellent performance according to the half-watt rm test (described below). For example, when discharging at 1.1 volts according to the half-watt rm test, the AAA battery can give at least about 0.4 hours, at least about 0.45 hours, at least about 0.5 hours or at least about 0.55 hours. When discharging at 0.9 volts according to the half-watt rm test, the AAA battery can give at least 0.9 hours, at least about 0.95 hours, at least about 1 hour or at least about 1.05 hours. The battery 10 can be an AAA battery that offers excellent performance according to the rm test of a quarter of a watt (described below).

For example, when 1.1 volts are discharged according to the quarter-watt rm test, the AAA battery can give at least about 2 hours, at least about 2.1 hours, at least about 2.2 hours or at least about 2. 3 hours. When discharging at 0.9 volts according to the rm test of a quarter of a watt, the AAA battery can give at least 3.1 hours, at least about 3.25 hours, at least approximately 3. 4 hours or at least approximately 3.5 hours.

EXAMPLE I The AA batteries were prepared with the following components. The cathode included approximately 9,487 grams of manganese dioxide (Kerr-McGee, Co.), about 0.806 grams of non-expanded, non-synthetic graphite, which has an average particle size of about 7 microns (Brazilian National Grafite) and about 0.3 weight percent of coathylene HA-1681. The anode included approximately 3,976 grams of zinc particles, approximately 50 ppm of surfactant (RM510, Rhone Poulenc) relative to zinc, and approximately 0.5 weight percent of total gelling agent (Carbopol 940 and A221). The porosity of the cathode was approximately 26%, and the porosity of the anode was approximately 2,173 grams of zinc per cubic centimeter of anode. The separator was a two-layer structure with each layer formed of a nonwoven material that included approximately 57 weight percent PVA fibers (approximately 0.5 denier to 6 millimeters), approximately 30 weight percent cellulose fibers (approximately 1.5 denier to 6 millimeters), and approximately 13 weight percent of PVA binder. Each layer was approximately 137.1 micrometers (5.4 thousandths of an inch) thick when dry and about 254 micrometers (10 mils) thick when wet. Each layer had a weight of approximately 54 grams per square meter. The separator _ did not include an adhesive, and the layers were substantially devoid of any filler. The battery also included approximately 3,598 grams of an aqueous solution of potassium hydroxide (approximately 35.5 weight percent potassium hydroxide). A thin coating of EB005 (Acheson) was placed between the outer wall of the battery and the outer periphery of the cathode. The AA batteries were stored at a temperature of about 20.1 ° C to about 22.1 ° C for five days. The batteries AA were then stored according to the following procedure. Each battery is usually tested for leakage or damage to the material, identified such that the identification of the battery can be maintained throughout the test program. The batteries are oriented on their sides in retention trays such that the batteries are not in physical contact with each other. The retention trays are made to be resistant to heat and electrolytes. The trays are stored for 1 day at ambient conditions, after which the trays are placed in a preheated chamber. The trays are spaced so that there is at least about 5 cm (2 inches) of space between the wall of the chamber, and the tray above, below, or adjacent to each tray. The following 24-hour test sequence, shown in Table I, is repeated for 14 days.

The trays are removed from the chamber and each battery is visually examined for leakage or damage to the material.

Table I Cycle number Time (Hours) Temperature (+ 2 ° C) 1 6.0 Variation from 28 to 25 2 4.5 Variation from 25 to 34 3 2.0 Variation from 34 to 43 4 1.0 Variation from 43 to 48 1.0 Variation from 48 to 55 6 1.0 Variation from 55 to 48 7 1.0 Variation from 48 to 43 8 3.0 Variation from 43 to 32 9 4.5 Variation from 32 to 28 24.0 (1 day) The following tests were subsequently performed on individual AA batteries. Each test was conducted at a temperature of about 20.1 ° C to about 22.1 ° C.

An AA battery was discharged from an open circuit voltage of approximately 1.6 volts under constant current conditions of ten seconds per minute for one hour per day ("photo test"). The AA battery reached 1 volt after 202 pulses, and the AA battery reached 0.8 volts after 443 pulses. An AA battery was continuously discharged from an open circuit voltage of 1.6 volts to 1 watt ("continuous 1 watt test"). The AA battery reached 1 volt after approximately 0.75 hours, and the AA battery reached 0.8 volts after approximately 1.00 hours. An AA battery was continuously discharged from an open circuit voltage of approximately 1.6 volts at a rate that alternated between 1 watt (3 second pulses) and 0.1 watt (7 second pulses) ("pulsed test"). The AA battery reached 1 volt after approximately 2.16 hours, and the AA battery reached 0.8 volts after approximately 3.72 hours. An AA battery was discharged from an open-circuit voltage of approximately 1.6 volts to 0.5 watts per 15 minutes per hour ("the half-watt rm test"). The AA battery reached 1.1 volts after approximately 1.87 hours, and the AA battery reached 0.9 volts after approximately 3.34 hours.

EXAMPLE II An AAA battery was prepared. Cathode 12 included approximately 4155 grams of manganese dioxide (Kerr McGee, Co.), approximately 0.353 grams of unexpanded, non-synthetic graphite having an average particle size of approximately 7 microns (Brazilian National Grafite) and approximately 0.3 percent by weight of coathylene HA-1681. Anode 14 included approximately 1,668 grams of zinc particles, approximately 50 ppm of surfactant (RM 510, Rhone Poulenc) in relation to zinc, and approximately 0.5 weight percent total gelling agent (Carbopol 940 and A221). The porosity of the cathode was approximately 26%, and the porosity of the anode was approximately 2.266 grams of zinc per cubic centimeter of anode 14. The separator included two layers of nonwoven material. The separator was a two-layer structure with each layer formed of a nonwoven material that included approximately 57 weight percent PVA fibers (approximately 0.5 denier to 6 millimeters), approximately 30 weight percent cellulose fibers (approximately 1.5 denier to 6 millimeters) and about 13 weight percent of PVA binder. Each layer was approximately 137.1 micrometers (5.4 thousandths of an inch) thick when dry and approximately 254 micrometers (10 mils) thick when wet. Each layer had a basis weight of approximately 54 grams per square meter. The separator did not include an adhesive, and the layers were substantially devoid of any filler. The battery also included 1.72 grams of an aqueous solution of potassium hydroxide (approximately 35.5 weight percent). A thin coating of EB005 (Acheson) was placed between the outer wall of the battery and the outer periphery of the cathode. The AA batteries were stored as described in Example I. Each AAA battery was discharged from an open circuit voltage of approximately 1.6 volts, and the tests were conducted within the temperature range described in Example I.

An AAA battery was continuously discharged from an open circuit voltage of approximately 1.6 volts at half a watt ("continuous half-watt test"). The AAA battery reached 1 volt after approximately 0.76 hours, and the AAA battery reached 0.8 volts after approximately 0.96 hours. With the test pressed, an AAA battery took approximately 0.55 hours to reach 1 volt, and approximately 0.84 hours to reach 0.8 volts. With the rm half-watt test, it took an AAA battery approximately 0.57 hours to reach 1 volt, and approximately 1.08 hours to reach 0.8 volts. An AAA battery was discharged from an open circuit voltage of approximately 1.6 volts to 0.25 watts for 15 minutes per hour ("the rm test of a quarter of a watt"). The AAA battery reached 1.1 volts after approximately 2.4 hours, and the AAA battery reached 0.9 volts after approximately 3.65 hours.

EXAMPLE III The AA batteries were prepared with the following components. The cathode included approximately 9.11 grams of manganese dioxide (40:60 weight mixture of Delta: osoh), approximately 0.810 grams of non-expanded, non-synthetic graphite, which has an average particle size of approximately 7 microns (Brazilian National de Grafite ) and about 0.8 weight percent titanium dioxide (Kronos). The anode included approximately 3.89 grams of zinc particles, approximately 0.88 percent by weight of total gelling agent (3 V and CL 15), and approximately 50 ppm of surfactant (RM 510, Rhone Poulenc). The porosity of the cathode was approximately 23%, and the porosity of the anode was approximately 2,173 grams of zinc per cubic centimeter of anode. The separator included a layer of non-woven material (PA 36 A, PDM) a layer of PA36C and a cellophane layer (25.4 μm (1 mil) thick). The cellophane was adjacent to the cathode, and the non-woven PA36A layer was adjacent to the anode. The battery also included approximately 3.62 grams of aqueous potassium hydroxide solution (approximately 35.5 weight percent potassium hydroxide). A thin coating of EB 005 (Acheson) was placed between the outer wall of the battery and the outer periphery of the cathode. The AA batteries were stored at a temperature of about 20.1 ° C to about 22.1 ° C for approximately five days according to the protocol described in Example I.

The following tests were subsequently performed on individual AA batteries. Each test was conducted at a temperature of about 20.1 ° C to about 22.1 ° C. The AA battery was discharged according to the photo test. 'The AA battery reached 1 volt after 180 pulses, and the AA battery reached 0.8 volts after 347 pulses. An AA battery was discharged according to the continuous 1 watt test. AA battery reached 1 volt after approximately 0.57 hours, and the AA battery reached 0.8 volts after approximately 0.80 hours. An AA battery was continuously discharged from an open circuit voltage according to the pulsed test. The AA battery reached 1 volt after approximately 1.76 hours, and the AA battery reached 0.8 volts after approximately 3.11 hours. An AA battery was discharged according to the half-watt rm test. The AA battery reached 1.1 volts after approximately 1.66 hours, and the AA battery reached 0.9 volts after approximately 3.05 hours. Other embodiments are within the claims.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates.

Claims (42)

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. An alkaline battery, characterized in that it comprises: a cathode that includes manganese dioxide; an anode that includes zinc particles; an electrolyte solution; and a separator placed between the cathode and the anode, wherein a weight ratio of the manganese dioxide to the electrolyte solution is from about 2.2 to about 2.9 and a weight ratio of the zinc particles to the electrolyte solution is about 0.9 to approximately 1.25.

2. The alkaline battery according to claim 1, characterized in that the carbon particles are non-synthetic, non-expanded graphite particles having an average particle size of less than about 20 microns.

3. The alkaline battery according to claim 1, characterized in that the alkaline battery is selected from the group consisting of AA batteries, AAA batteries, AAA batteries, C batteries and D batteries.

4. The alkaline battery according to claim 1, characterized in that the separator comprises a non-woven, non-membranous material, and a second non-woven, non-woven material placed along a surface of the first material.

5. The alkaline battery according to claim 1, characterized in that the cathode has a porosity of about 21% up to about 28%.

6. The alkaline battery according to claim 1, characterized in that the anode has a porosity of about 2 grams of zinc particles per cubic centimeter to about 2.45 grams of zinc particles per cubic centimeter.

7. An alkaline battery, characterized in that it comprises: a cathode that includes manganese dioxide; an anode that includes zinc particles; an electrolyte solution; and a separator positioned between the cathode and the anode, wherein a weight ratio of the manganese dioxide to the electrolyte solution is from about 2.2 to about 2.9 and a weight ratio of the zinc particles to the electrolyte solution is about 1.1. at approximately 1.25.

8. The alkaline battery according to claim 7, characterized in that the carbon particles are non-synthetic, non-expanded graphite particles, having an average particle size of less than about 20 microns.

9. The alkaline battery according to claim 7, characterized in that the alkaline battery is selected from the group consisting of AA batteries, AAA batteries, AAAA batteries, C batteries and D batteries.

10. The alkaline battery according to claim 7, characterized in that the separator comprises a non-woven, non-membranous material, and a second non-woven, non-woven material placed along a surface of the first material.

11. The alkaline battery according to claim 7, characterized in that the cathode has a porosity of about 21% up to about 28%.

12. The alkaline battery according to claim 7, characterized in that the anode has a porosity of about 2 grams of zinc particles per cubic centimeter to about 2.45 grams of zinc particles per cubic centimeter.

13. An alkaline battery, characterized in that it comprises: a cathode that includes manganese dioxide; an anode that includes zinc particles; and a separator positioned between the cathode and the anode, wherein a weight ratio of the manganese dioxide to the electrolyte solution is from about 2.5 to about 2.65 and a weight ratio of the zinc particles to the electrolyte solution is about 0.9. up to about 1.2.

14. The alkaline battery according to claim 13, characterized in that the carbon particles are non-synthetic, non-expanded graphite particles having an average particle size of less than about 20 microns.

15. The alkaline battery according to claim 13, characterized in that the alkaline battery is selected from the group consisting of AA batteries, AAA batteries, AAA batteries, C batteries and D batteries.

16. The alkaline battery according to claim 13, characterized in that the separator comprises a non-woven, non-membranous material, and a second non-woven, non-woven material placed along a surface of the first material.

17. The alkaline battery according to claim 13, characterized in that the cathode has a porosity of about 21% up to about 28%.

18. The alkaline battery according to claim 13, characterized in that the anode has a porosity of about 2 grams of zinc particles per cubic centimeter to about 2.45 grams of zinc particles per cubic centimeter.

19. An alkaline AA battery, characterized in that it comprises: a cathode; an anode; and a separator, wherein the AA alkaline battery gives at least 150 pulses to discharge at 1 volt according to a photo test.

20. The AA alkaline battery according to claim 19, characterized in that the AA alkaline battery gives at least 350 pulses to discharge at 0.8 volts according to the photo test.

21. The AA alkaline battery according to claim 19, characterized in that the cathode comprises manganese dioxide and carbon particles, and wherein the anode comprises zinc particles.

22. An AA alkaline battery, characterized in that it comprises: a cathode; an anode; and a separator, where the AA alkaline battery gives at least approximately "0.6 hours to discharge at 1 volt according to a continuous 1 watt test."

23. The AA alkaline battery according to claim 22, characterized in that the AA alkaline battery gives at least about 0.95 hours to discharge at 0.8 volts according to the continuous 1 watt test.

24. The AA alkaline battery according to claim 22, characterized in that the cathode comprises manganese dioxide and carbon particles, and wherein the anode comprises zinc particles.

25. An AA alkaline battery, characterized in that it comprises: a cathode; an anode; and a separator, wherein the AA alkaline battery gives at least about 1.6 hours to discharge at 1 volt according to a pulse test.

26. The AA alkaline battery according to claim 25, characterized in that the AA alkaline battery gives at least about 2.75 hours to discharge at 0.8 volts according to the pulse test.

27. The AA alkaline battery according to claim 25, characterized in that the cathode comprises manganese dioxide and carbon particles, and wherein the anode comprises zinc particles.

28. An AA alkaline battery, characterized in that it comprises: a cathode; an anode; and a separator, where the alkaline battery AA gives at least approximately 1.5 hours to discharge at 1.1 volts according to the half-watt rm test.

29. The AA alkaline battery according to claim 28, characterized in that the AA alkaline battery gives at least about 2.9 hours to discharge at 0.9 volts according to the half-watt rm test.

30. The AA alkaline battery according to claim 28, characterized in that the cathode comprises manganese dioxide and carbon particles, and wherein the anode comprises zinc particles.

31. An AAA alkaline battery, characterized in that it comprises: a cathode; an anode; and a separator, where the AAA alkaline battery gives at least about 2 hours to discharge at 1.1 volts according to the rm test of a quarter of a watt.

32. The AAA alkaline battery according to claim 31, characterized in that the AAA alkaline battery gives at least 3.1 hours to discharge at 0.9 volts according to the half-watt rm test.

33. The AAA alkaline battery according to claim 31, characterized in that the cathode comprises manganese dioxide and carbon particles, and wherein the anode comprises zinc particles.

34. An AAA alkaline battery, characterized in that it comprises: a cathode; an anode; and a separator, wherein the AAA alkaline battery gives at least about 0.65 hours to discharge at 1 volt according to a continuous half-watt test.

35. The AAA alkaline battery according to claim 34, characterized in that the AAA alkaline battery gives at least about 0.9 hours to discharge at 0.9 volts according to the continuous half-watt test.

36. The AAA alkaline battery according to claim 34, characterized in that the cathode comprises manganese dioxide and carbon particles, and wherein the anode comprises zinc particles.

37. An AAA alkaline battery, characterized in that it comprises: a cathode; an anode; and a separator, wherein the AAA alkaline battery gives at least about 0.35 hours to discharge at 1 volt according to a pulsed test.

38. The AAA alkaline battery according to claim 37, characterized in that the AAA alkaline battery gives at least about 0.65 hours to discharge at 0.9 volts according to the pulsed test.

39. The AAA alkaline battery according to claim 37, characterized in that the cathode comprises manganese dioxide and carbon particles, and wherein the anode comprises zinc particles.

40. An AAA alkaline battery, characterized in that it comprises: a cathode; an anode; and a separator, wherein the AAA alkaline battery gives at least about 0.4 hours to discharge at 1.1 volts according to a half-watt rm test.

41. The AAA alkaline battery according to claim 40, characterized in that the AAA alkaline battery gives at least about 0.9 hours to discharge at 0.9 volts according to the half-watt rm test.

42. The AAA alkaline battery according to claim 40, characterized in that the cathode comprises manganese dioxide and carbon particles, and wherein the anode comprises zinc particles.