Lead oxide, composition containing lead oxide, and method for preparing lead oxide

Abstract

Provided herein is a composition comprising one or more of alpha lead oxide, beta lead oxide, metallic lead, Pb2O3, and Pb3O4, the composition comprising particles comprising sub-particles, the sub-particles having an average maximum size of from 10 to 300 nm. Also described herein are methods of making such compositions.

Description

Background Art

[0001] The present disclosure relates to lead oxide.

[0002] The present invention relates to lead oxides, such as alpha lead (II) oxide, beta lead (II) oxide, red lead and Pb 2 O 3 More particularly, but not exclusively, the present invention relates to a method for preparing such lead oxide, a composition containing such lead oxide, a battery plate made using such a composition, and a battery having such a battery plate.

[0003] Lead oxide is used in the manufacture of lead-acid batteries. This lead oxide can be obtained by recycling lead-acid batteries. Conventional recycling methods are energy intensive and usually involve smelting, i.e. high temperature heating is required. WO2008 / 056125 describes a low energy method for recycling lead for use in lead-acid batteries, comprising forming lead citrate and then forming a composition containing lead and / or lead (II) oxide. The composition can then be used to manufacture battery plates for use in lead-acid batteries.

[0004] The present invention seeks to alleviate one or more of the above problems. Additionally or alternatively, the present invention seeks to provide an improved method for preparing lead oxide. Summary of the invention

[0005] According to a first aspect of the present invention, there is provided a method for preparing a composition containing alpha lead (II) oxide, the method comprising: Conversion of organic lead salts into PbOPbCO 3 ;as well as The PbOPbCO is heated in a substantially inert atmosphere. 3 .

[0006] The present inventors have discovered that alpha lead(II) oxide can be prepared by converting an organic lead salt (e.g., lead citrate) into lead(II) oxide, optionally converting the lead(II) oxide into PbOPbCO 3 ; then heat PbOPbCO 3 As used herein, "lead oxide" refers to lead (II) oxide (PbO) unless the context requires otherwise.

[0007] Lead (II) oxide, commonly known as yellow lead, has a tetragonal crystal structure.

[0008] The organic lead salt may be anhydrous or partially or completely hydrated. The organic lead salt may include a lead carboxylate. The carboxylate may be aliphatic. The carboxylate may be linear or branched. The carboxylate may be saturated or unsaturated. The carboxylate may be an alkyl carboxylate. The carboxylate may include at least 2 carbon atoms, optionally at least 3 carbon atoms, optionally at least 4 carbon atoms, optionally at least 5 carbon atoms, optionally at least 6 carbon atoms. The carboxylate may include up to 20 carbon atoms, optionally up to 18 carbon atoms, optionally up to 16 carbon atoms, optionally up to 14 carbon atoms, optionally up to 12 carbon atoms, optionally up to 10 carbon atoms, optionally up to 8 carbon atoms. The carboxylate may include 2 to 15 carbon atoms, optionally 2 to 12 carbon atoms, optionally 2 to 8 carbon atoms, optionally 2 to 6 carbon atoms.

[0009] The organic lead salt may include a lead salt of a monocarboxylic acid, such as lead acetate. The monocarboxylic acid may optionally be a saturated acid. The monocarboxylic acid may optionally be a straight chain acid or a branched chain acid. The organic lead salt may include a lead salt of a dicarboxylic acid, such as glutaric acid. The dicarboxylic acid may optionally be a saturated acid. The dicarboxylic acid may optionally be a straight chain acid or a branched chain acid. The organic lead salt may include a lead salt of a tricarboxylic acid, such as citric acid. The tricarboxylic acid may optionally be a saturated acid. The tricarboxylic acid may optionally be a branched chain acid.

[0010] The organic lead salt is preferably lead citrate.

[0011] For convenience, the term "lead citrate" is used to refer to Pb(C 6 H 6 O 7 ) and its hydrates, as well as other stoichiometries, such as 3Pb.2(C 6 H 5 O 7 ) and its hydrates. In certain aspects of the present invention, the term "lead citrate" is used to refer to Pb(C 6 H 6 O 7 ) and its hydrate, and treating PbSO with citric acid aqueous solution and trisodium citrate aqueous solution 4 In other aspects of the present invention, the term "lead citrate" is used to refer to Pb(C 6 H 6 O 7 ) and its hydrates. Specifically, "lead citrate" may refer to trilead biscitrate [3Pb.2(C 6 H 5 O 7 )] (commonly known as trilead citrate) and its hydrates.

[0012] The organic lead salt (e.g., lead citrate) is optionally provided in the form of particles, optionally in the form of elongated particles, optionally in the form of rod-shaped particles. The average maximum dimension of the organic lead salt particles may be at least 0.5 μm, optionally at least 1.0 μm, optionally at least 1.5 μm, optionally at least 2.0 μm. The average maximum dimension of the organic lead salt particles is optionally no more than 20 μm, optionally no more than 15 μm, optionally no more than 10 μm. The inventors have found that the use of relatively large organic lead salt particles (particularly lead citrate) is conducive to the formation of alpha lead (II) oxide. The average aspect ratio of the organic lead salt particles may be at least 1.5:1, optionally at least 2.0:1, optionally at least 3.0:1. The average aspect ratio of the organic lead salt particles is optionally no more than 20:1, optionally no more than 15:1, optionally no more than 10:1, optionally no more than 7.5:1, optionally no more than 5:1.

[0013] Conversion of an organic lead salt (optionally lead citrate) to PbOPbCO 3 The method may include converting an organic lead salt into lead (II) oxide, converting the lead (II) oxide into lead carbonate, and converting lead carbonate into PbOPbCO 3 The conversion of the organic lead salt into lead (II) oxide may include reacting the organic lead salt with an oxidizing agent (e.g., an oxidizing gas, such as a gas containing oxygen, such as a gas containing molecular oxygen O 2 The conversion of the lead (II) oxide into lead carbonate may include heating the lead (II) oxide in the presence of carbon dioxide. The heating of the organic lead salt to form lead (II) oxide and the conversion of the lead (II) oxide into lead carbonate may be performed sequentially and / or simultaneously. For example, the heating of the organic lead salt may be performed in the presence of an oxidant (e.g., an oxidizing gas, such as a gas containing molecular oxygen O). 2 The method of the present invention is to heat the lead citrate in the presence of an oxidizing gas (e.g., a 2-hydroxy-1-nitrogen-2-yl)-2-nitrogen (2-hydroxy-1-nitrogen) and carbon dioxide to form lead (II) oxide and convert the lead (II) oxide into lead carbonate. Thus, converting the organic lead salt into lead carbonate may include heating the organic lead salt in the presence of an oxidizing gas and carbon dioxide. Without being bound by theory, it is understood that heating the organic lead salt in the presence of an oxidizing agent will form beta lead (II) oxide. Those skilled in the art will recognize that beta lead (II) oxide may not be the only product formed. Beta lead (II) oxide reacts with carbon dioxide to form lead carbonate.

[0014] Conversion of lead carbonate into PbOPbCO 3 The heating of the lead carbonate may include heating the lead carbonate. The heating of the lead carbonate optionally results in the formation of lead oxide (optionally alpha lead oxide). The lead oxide may react with the lead carbonate to form PbOPbCO 3For the avoidance of doubt, the conversion of lead carbonate to lead oxide may be a reversible process. Lead carbonate, when heated, produces lead oxide and carbon dioxide. Lead oxide and carbon dioxide may react to produce lead carbonate.

[0015] If the oxidant comprises a gas (e.g., containing molecular oxygen O 2 The method may include contacting the lead citrate with the oxidant stream.

[0016] The carbon dioxide may be provided as a carbon dioxide stream. The method may comprise contacting the lead (II) oxide with the carbon dioxide stream.

[0017] If the oxidant contains molecular oxygen (e.g., if air is used as the oxidant) and if forming lead carbonate comprises heating lead (II) oxide in the presence of carbon dioxide, the molar ratio of carbon dioxide to molecular oxygen may optionally be at least 10:1, optionally may be at least 12:1, optionally may be at least 15:1, optionally may be at least 18:1, optionally may be at least 20:1, optionally may be at least 25:1, optionally may be at least 30:1, optionally may be at least 40:1, optionally may be at least 50:1. The inventors have found that a molar ratio of carbon dioxide to molecular oxygen of at least 25:1 may be beneficial because the amount of alpha lead oxide in the final composition is significantly greater than when the molar ratio is 12:1. The inventors have also found that a molar ratio of carbon dioxide to molecular oxygen of at least 50:1 may be beneficial because the amount of alpha lead oxide in the composition is significantly greater than when the molar ratio is 40:1. For the avoidance of doubt, if air is used to provide the molecular oxygen, the amount of molecular oxygen may be determined based on air comprising 21% oxygen. The present inventors have discovered that a relatively high ratio of carbon dioxide to molecular oxygen is effective in obtaining a high proportion of alpha lead oxide in the composition, particularly if an organic lead salt (e.g., lead citrate) is heated in a gas mixture containing molecular oxygen (e.g., air) and carbon dioxide.

[0018] The molar ratio of carbon dioxide to molecular oxygen may optionally be no more than 250:1, optionally no more than 200:1, optionally no more than 150:1, optionally no more than 100:1.

[0019] PbO 3 Heating in a substantially inert atmosphere (e.g., in nitrogen) to form alpha lead (II) oxide. PbOPbCO 3 It can be heated long enough to form lead(II) oxide. 3 The heating may be performed for at least 5 minutes, for at least 10 minutes, for at least 20 minutes, or for at least 30 minutes. 3The heating may be performed for no more than 120 minutes, for no more than 90 minutes, for no more than 75 minutes, or for no more than 60 minutes. It has been found that in order to produce a relatively large amount of alpha lead (II) oxide, PbOPbCO 3 Heat long enough.

[0020] PbO 3 It can be heated at a sufficiently high temperature to promote the formation of alpha lead(II) oxide. 3 The heating may be at a temperature of at least 250°C, optionally at least 275°C, optionally at least 300°C, and optionally at least 325°C. 3 Heating may optionally be performed at a temperature not exceeding 450°C, optionally not exceeding 425°C, optionally not exceeding 400°C, and optionally not exceeding 375°C.

[0021] PbO 3 Heating may be performed at a temperature of 300°C to 400°C, optionally at a temperature of 325°C to 375°C, optionally for 10 to 90 minutes, optionally for 20 to 60 minutes, optionally for about 30 minutes.

[0022] Those skilled in the art will recognize that the process of the present invention does not necessarily produce only alpha lead oxide, and the composition may contain other components, such as one or more of beta lead oxide, metallic lead, lead oxide carbonate, lead carbonate, red lead and carbon. However, the composition produced by the process of the present invention may contain at least 20 wt% alpha lead oxide, optionally at least 30 wt% alpha lead oxide, optionally at least 40 wt% alpha lead oxide, optionally at least 50 wt% alpha lead oxide, optionally at least 60 wt% alpha lead oxide, optionally at least 70 wt% alpha lead oxide, optionally at least 80 wt% alpha lead oxide, optionally at least 90 wt% alpha lead oxide, optionally at least 95 wt%, optionally at least 98 wt% alpha lead oxide by weight. For example, the alpha lead oxide content may be measured using acid dissolution or X-ray diffraction, as will now be described.

[0023] The composite samples were homogenized using a pestle and mortar. The homogenized samples were characterized using a B3 (BB) Broker D8 DAVINCI (Broker D8 Advance, USA) on Gen 9 in the range of 10° to 90° 2θ and Cu-Kα radiation. The step size was 0.0300° 2θ, the scan step size was 96.00 s (total step size 2628), each step was 0.5 s, the current was 40 mA, and the voltage was 40 kV. The diffraction data were background corrected and analyzed using the "Highscore" data analysis software (Broker-Pan Analytica), using library data on the target materials to identify the materials present and their relative amounts. This information is used to calculate the relative proportions of alpha lead oxide and beta lead oxide in the composition. A limitation of using X-ray diffraction is that if a particular material dominates (e.g., lead oxide), the diffraction peaks of other materials may be difficult to identify and / or quantify. X-ray diffraction can also be used to identify and / or quantify other oxides of lead, such as Pb 2 O 3 and Pb 3 O 4 However, identifying and / or quantifying materials below about 10 wt % can be difficult.

[0024] Acid dissolution can be used to determine the relative amounts of the various components in the composition. 2 g of the composition is contacted with 50 mL of 5% aqueous acetic acid in a 250 mL conical flask and the suspension is stirred at 500 rpm for 5 minutes using a magnetic stirrer. Any lead oxide dissolves in the acetic acid, leaving metallic lead, carbon, red lead and Pb 2 O 3 One or more of the undissolved materials are undissolved. Whether the undissolved material floats depends in part on the particle size, the density of the material, and the charge of the particles. Dense materials tend to settle. However, very small particles tend to remain suspended. Therefore, it is possible for small particles of inherently dense materials to float. However, in general, carbon and metallic lead (sometimes coated with carbon) will settle to the bottom of the flask, while red lead and Pb 2 O 3 Keep it suspended.

[0025] The suspension or solution is decanted from the solid material settled at the bottom of the flask, if any.

[0026] If the precipitate appears black, this indicates the presence of carbon. The precipitate is washed with water and dried to determine the weight of the precipitate. The precipitate is then rinsed with water to separate the carbon from the metallic lead by density differences. The precipitate is rinsed to facilitate separation until the heavier solid portion no longer appears black, indicating that the heavier solid portion is metallic lead. The metallic lead is then dried. The weight of the metallic lead can then be determined. The weight of the carbon can also be determined. The ratio of metallic lead to carbon in the composition can also be determined.

[0027] If the suspension in the flask appears reddish orange, this indicates the presence of red lead. The suspension is filtered and the residue is washed with Milli-Q high purity water and dried. The weight of red lead can then be determined from the weight of the residue and the proportion of red lead in the composition can be determined.

[0028] If the suspension in the flask appears brown, it indicates the presence of Pb 2 O 3 As mentioned above, Pb 2 O 3 The weight percent (wt %) is determined by reference to X-ray diffraction data.

[0029] As described above, alpha lead oxide and beta lead oxide dissolve in acid to form lead acetate. The solvent can be removed to obtain lead acetate, which can be used to calculate the total amount of alpha lead oxide and beta lead oxide in the sample. The relative amounts of alpha lead oxide and beta lead oxide in the original sample before acid dissolution are determined using X-ray diffraction data, and the relative amounts of alpha lead oxide and beta lead oxide determined by X-ray diffraction are used to calculate the amount of alpha lead oxide and beta lead oxide in the composition.

[0030] The method of the first aspect of the invention may be carried out in a rotary furnace.

[0031] As described above, the method of the first aspect of the present invention is used to prepare a composition containing alpha lead oxide. According to the second aspect of the present invention, there is provided a composition containing alpha lead oxide, which can be prepared by the method of the first aspect of the present invention, or is prepared by the method. The composition may include those parameters related to the method of the first aspect of the present invention above. The composition may contain, for example, at least 80wt% of alpha lead oxide by weight, optionally at least 85wt% of alpha lead oxide by weight, optionally at least 90wt% of alpha lead oxide by weight, optionally at least 95wt% of alpha lead oxide by weight, optionally at least 98wt% of alpha lead oxide by weight, and may optionally be essentially composed of alpha lead oxide. The composition may contain metallic lead.

[0032] The composition may include particles. The composition may include rod-shaped particles. The composition may include amorphous particles (i.e., particles without a well-defined shape). The composition may include particles having holes and / or channels therein. Such particles may have a network structure containing holes and / or channels therein. The particles may include subparticles. Subparticles are smaller than particles. At least some subparticles may optionally be in the form of protrusions. The average maximum dimension of the particles may optionally be 0.2 μm to 20 μm. The average maximum dimension of the subparticles may optionally be at least 10 nm, optionally at least 15 nm, optionally at least 20 nm, optionally at least 25 nm, optionally at least 30 nm, optionally at least 40 nm, optionally at least 50 nm. The average maximum dimension of the subparticles may be no more than 300 nm, optionally no more than 250 nm, optionally no more than 200 nm, optionally no more than 150 nm, optionally no more than 100 nm. The average maximum dimension of the subparticles may be from 10 to 300 nm, optionally from 15 nm to 200 nm, optionally from 20 nm to 150 nm. The subparticles may be spherical or subspherical. The subparticles may have the same or different chemical composition as the rest of the particle.

[0033] The present inventors have discovered that a composition containing lead-based materials useful in the battery industry has advantageous properties (particularly a relatively high surface area) if the composition comprises relatively large particles on which relatively small subparticles (which subparticles may be in the form of protrusions) are formed.

[0034] The size of particles and subparticles may be measured using any suitable method, such as scanning electron microscopy.

[0035] Optionally, at least 20% of the particles of the composition are rod-shaped particles. Optionally, at least 40%, optionally at least 50%, optionally at least 60%, optionally at least 70%, optionally at least 80%, optionally at least 90%, optionally at least 95% of the particles of the composition are rod-shaped.

[0036] Optionally, among the rod-shaped particles, optionally at least 50% by number have a maximum dimension of 0.2 μm to 20 μm, optionally at least 60% by number, optionally at least 70% by number, optionally at least 80% by number, optionally at least 90% by number have a maximum dimension of 0.2 μm to 20 μm.

[0037] As described above, the composition optionally includes rod-shaped particles. The average aspect ratio of the rod-shaped particles may be at least 1.5:1, optionally at least 2.0:1, optionally at least 3.0:1. The average aspect ratio of the rod-shaped particles may not exceed 20:1, optionally not exceed 15:1, optionally not exceed 10:1, optionally not exceed 7.5:1, optionally not exceed 5:1.

[0038] Optionally, among the rod-shaped particles, optionally at least 50% by number, optionally at least 60% by number, optionally at least 70% by number, optionally at least 80% by number, optionally at least 90% by number have an aspect ratio of at least 1.5: 1, optionally at least 2.0: 1, optionally at least 3.0: 1. Optionally at least 50% by number, optionally at least 60% by number, optionally at least 70% by number, optionally at least 80% by number, optionally at least 90% by number have an aspect ratio of no more than 20: 1, optionally no more than 15: 1, optionally no more than 10: 1, optionally no more than 7.5: 1, optionally no more than 5: 1.

[0039] The composition may include particles having a core portion rich in metallic lead and poor in oxides, and an outer portion rich in oxides. The inventors have found that the core portion of some particles is rich in metallic lead and has a low lead oxide content, while the outer portion is rich in lead oxides. Such an arrangement may be advantageous because the outer portion can effectively protect the core portion from oxidation when the composition is exposed to air. Without being bound by theory, it is foreseeable that a battery made from such a composition may have a longer cycle life because the outer portion protects the core portion from sulfation.

[0040] The core portion may comprise at least 95 wt% metallic lead, optionally at least 96 wt% metallic lead, optionally at least 98 wt% metallic lead by weight.The core portion may be substantially free of lead oxide.

[0041] The outer part may contain alpha lead oxide, beta lead oxide, red lead and Pb 2 O 3 One or more of .

[0042] The core portion may be spherical or sub-spherical.

[0043] The volume of the core part is optionally greater than the volume of the outer part. The volume of the core part is optionally at least twice, optionally at least three times, optionally at least five times, optionally at least ten times, optionally at least fifteen times, optionally at least twenty times, optionally at least thirty times, optionally at least forty times, optionally at least fifty times, optionally at least one hundred times the volume of the outer part.

[0044] The average maximum dimension of the core portion may be at least 1 μm, optionally at least 2 μm, optionally at least 5 μm, optionally at least 10 μm. The average maximum dimension of the core portion may optionally be no more than 100 μm, optionally no more than 80 μm, optionally no more than 60 μm, optionally no more than 50 μm, optionally no more than 40 μm, optionally no more than 30 μm.

[0045] The BET surface area of ​​the composition (optionally measured using nitrogen, optionally at 77 K) is optionally at least 1.0 m 2 / g, optional at least 1.5m 2 / g, optional at least 1.8m 2 / g, optional at least 2.0m 2 / g, optional at least 2.5m 2 / g, optional at least 3.0m 2 / g. BET surface area (optionally measured using nitrogen, optionally at 77K) is optionally not more than 10m 2 / g, optionally not more than 8m 2 / g, optionally not more than 6m 2 / g, optionally not more than 5m 2 / g.

[0046] The data obtained for determining the BET surface area can also be used to determine the pore volume. In this regard, the pore volume determined by BJH analysis (optionally using nitrogen, optionally at 77 K) is optionally at least 0.0050 cm 3 g -1 , optionally at least 0.0060 cm 3 g -1 , optionally at least 0.0070 cm 3 g -1 The pore volume as determined by BJH analysis is optionally no greater than 0.025 cm 3 g -1 , optionally not more than 0.020 cm 3 g -1 , optionally not more than 0.015 cm 3 g -1 , optionally not more than 0.010 cm 3 g -1 , optionally not exceeding at least 0.0080 cm 3 g -1 , optionally not more than 0.0070 cm 3 g -1 .

[0047] The pore size of the composition as determined by adsorption measurements may optionally be at least Optionally at least Optionally at least Optionally at least Optionally at least Optionally at least Optionally at least The pore size determined by adsorption measurements may optionally be no greater than Optionally not more than Optionally not more than Optionally not more than Optionally not more than Optionally not more than Optionally not more than Optionally not more than Optionally not more than

[0048] The acid absorption of the composition may optionally be at least 200 mg of acid per gram of sample, optionally at least 220 mg of acid per gram of sample, optionally at least 240 mg of acid per gram of sample. The acid absorption may optionally be no more than 1000 mg of acid per gram of sample, optionally no more than 800 mg of acid per gram of sample, optionally no more than 600 mg of acid per gram of sample, optionally no more than 500 mg of acid per gram of sample, optionally no more than 400 mg of acid per gram of sample, optionally no more than 350 mg of acid per gram of sample, optionally no more than 300 mg of acid per gram of sample, optionally no more than 280 mg of acid per gram of sample. The acid absorption may be determined using sulfuric acid, such as 16 wt % sulfuric acid. For the avoidance of doubt, the terms "acid absorption" and "acid adsorption" are often used interchangeably in the art.

[0049] According to a third aspect of the present invention, there is also provided a method for preparing a composition containing beta lead (II) oxide, the method comprising heating an organic lead salt in a gas stream containing an oxidant.

[0050] The present inventors have surprisingly discovered that the formation of beta lead (II) oxide can be better controlled by contacting an organic lead salt (eg lead citrate) with a gas stream containing an oxidant.

[0051] Beta lead oxide, commonly known as red lead, has an orthorhombic structure that can be easily identified by X-ray diffraction.

[0052] The gas containing the oxidant typically contains an inert diluent. For example, the gas may include air, which contains an oxidant in the form of molecular oxygen and an inert diluent in the form of nitrogen. It has been found that the presence of an inert diluent is beneficial to the formation of beta lead oxide. Although air contains an inert diluent in the form of nitrogen, the inventors have found that it may be beneficial to further reduce the concentration of the oxidant. Therefore, the method may include mixing a precursor gas containing an oxidant with a diluent gas to provide a gas containing an oxidant. For example, the precursor gas may include air. The diluent gas may be an inert diluent and may include, for example, nitrogen. The molar ratio of the diluent gas to the precursor gas (particularly if the precursor gas is air) may be at least 1:10, optionally at least 1:5, optionally at least 1:2.5, optionally at least 1:2, optionally at least 1:1.5. The molar ratio of the diluent gas to the precursor gas may optionally be no more than 5:1, optionally no more than 4:1, optionally no more than 3:1, optionally no more than 2:1. The molar ratio of the diluent gas to the precursor gas may be 1:10 to 5:1, optionally 1:5 to 3:1, optionally 1:2 to 2:1. Using the diluent gas to dilute the oxidant reduces the concentration of the oxidant, thereby reducing the temperature rise caused by the exothermic reaction of the oxidant with lead citrate. At higher temperatures, the formation of metallic lead is promoted. At lower temperatures, the formation of beta lead oxide is favored.

[0053] If the oxidant is in the form of a gaseous oxidant, such as molecular oxygen, the gas optionally contains no more than 20 wt% oxidant, optionally no more than 18 wt% oxidant, optionally no more than 16 wt% oxidant, optionally no more than 14 wt% oxidant, optionally no more than 12 wt% oxidant, optionally no more than 10 wt% oxidant by weight.

[0054] If the oxidant is in the form of a gaseous oxidant, such as molecular oxygen, the gas optionally contains at least 1 wt% oxidant, optionally at least 2 wt% oxidant, optionally at least 3 wt% oxidant, optionally at least 5 wt% oxidant, optionally at least 7.5 wt% oxidant, optionally at least 10 wt% oxidant.

[0055] If the oxidant is in the form of a gaseous oxidant, such as molecular oxygen, the gas optionally contains 1-20 wt% oxidant, optionally 1-18 wt% oxidant, optionally 3-16 wt% oxidant, optionally 5-14 wt% oxidant.

[0056] When exposed to the gas stream, the organic lead salt may be heated to a temperature of at least 250° C., optionally at least 275° C., optionally at least 300° C., optionally at least 325° C. The lead carbonate may be heated to a temperature of no more than 450° C., optionally no more than 425° C., optionally no more than 400° C., optionally no more than 375° C.

[0057] When being exposed to air flow, organic lead salt can be optionally heated and be no more than 240 minutes, optionally be no more than 180 minutes, optionally be no more than 150 minutes, optionally be no more than 120 minutes, optionally be no more than 90 minutes, optionally be no more than 75 minutes, optionally be no more than 60 minutes.When being exposed to air flow, organic lead salt can be optionally heated at least 30 minutes, optionally at least 60 minutes, optionally at least 90 minutes.Those skilled in the art will recognize that the heat-up time may depend on the amount of organic lead salt and the volume of reaction chamber / stove.In this regard, the amount of organic lead salt is big more, and the heat-up time is long more.

[0058] The organic lead salt may be heated to a temperature of 275°C to 375°C for a period of 60-180 minutes, optionally 90-150 minutes, while exposed to the gas stream.

[0059] The inventors have found that the composition can be customized by changing the method of preparing the composition. For example, the inventors have found that by heating an organic lead salt (particularly lead citrate) to a temperature of 325-375°C in the presence of a gas stream containing a relatively low concentration of an oxidant (e.g., 6-10 wt%, such as can be achieved by mixing half or one volume of air with one volume of nitrogen), a composition containing a high percentage of beta lead oxide (e.g., at least 80 wt%, optionally at least 85 wt%, optionally at least 90 wt% beta lead oxide) can be obtained. Heating to a higher temperature (e.g., 400°C) and / or using a higher proportion of an oxidant (e.g., 13 wt%, such as can be achieved by mixing two volumes of air with one volume of nitrogen) can also provide a relatively high proportion of beta lead oxide (optionally at least 70 wt%, optionally at least 75 wt%, optionally at least 80 wt%, optionally at least 85 wt% beta lead oxide), a higher proportion of metallic lead (optionally at least 5 wt%, optionally at least 6 wt%, optionally at least 7 wt%, optionally at least 8 wt%). This is important because the presence of metallic lead in the composition is useful for preparing lead battery products. Heating to lower temperatures (e.g., 300-325°C) and / or using a higher proportion of oxidant (e.g., 13 wt%, such as can be achieved by mixing two volumes of air with one volume of nitrogen) can also provide a relatively high proportion of beta lead oxide (optionally at least 70 wt%, optionally at least 75 wt%, optionally at least 80 wt%, optionally at least 85 wt% beta lead oxide), a lower proportion of metallic lead (optionally not more than 5 wt%, optionally not more than 3 wt%, optionally not more than 1 wt%), a certain proportion of alpha lead oxide (e.g., at least 1 wt%, optionally at least 3 wt%, optionally at least 5 wt%).

[0060] Those skilled in the art will recognize that the process of the present invention does not necessarily produce only beta lead oxide, and components other than beta lead oxide may be present in the composition, for example, one or more of alpha lead oxide, metallic lead, red lead and carbon may be present. However, the composition produced by the process of the present invention may contain at least 60 wt% beta lead oxide, optionally at least 70 wt% beta lead oxide, optionally at least 80 wt% beta lead oxide, optionally at least 90 wt% beta lead oxide by weight. For example, the beta lead oxide content may be measured using acid dissolution or X-ray diffraction.

[0061] The organic lead salt may be as defined above in relation to the process of the first aspect of the invention.

[0062] The method of the third aspect of the invention may be carried out in a rotary furnace.

[0063] As described above, the method of the third aspect of the present invention is used to prepare a composition containing beta lead oxide. Therefore, according to the fourth aspect of the present invention, there is provided a composition containing beta lead oxide, which can be prepared by the method of the third aspect of the present invention, or is prepared by the method. The composition may contain, for example, at least 85wt% beta lead oxide, optionally at least 90wt% beta lead oxide by weight. The composition of the fourth aspect of the present invention may have any of the above-described features associated with the method of the third aspect of the present invention. The composition may contain metallic lead.

[0064] The composition of the fourth aspect of the invention may have those features described above for the composition of the second aspect of the invention. For example, the composition of the fourth aspect of the invention may optionally include particles containing sub-particles. The sub-particles may be protrusions.

[0065] According to a fifth aspect of the present invention, there is provided a method for preparing a composition containing red lead, the method comprising: Conversion of organic lead salts into PbOPbCO 3 ;as well as PbOPbCO 3 Converted to red lead.

[0066] Red lead is well known to those skilled in the art. The general formula of red lead is Pb 3 O 4 , also known as lead tetroxide, red lead and lead (II, IV) oxide.

[0067] Conversion of an organic lead salt (optionally lead citrate) to PbOPbCO 3 The method may optionally include converting an organic lead salt (optionally lead citrate) to lead (II) oxide, and optionally converting the lead (II) oxide to lead carbonate. The lead carbonate may be heated to form alpha lead oxide. The alpha lead oxide may react with the lead carbonate to form PbOPbCO3 The conversion of the organic lead salt into lead (II) oxide may include reacting the organic lead salt with an oxidizing agent (e.g., an oxidizing gas, such as a gas containing oxygen, such as a gas containing molecular oxygen O 2 The conversion of lead (II) oxide to lead carbonate may include heating the lead (II) oxide in the presence of carbon dioxide. The heating of the organic lead salt to form lead (II) oxide and the conversion of the lead (II) oxide to lead carbonate may be performed sequentially and / or simultaneously. For example, the heating of the organic lead salt may be performed in the presence of an oxidant (e.g., an oxidizing gas, such as a gas containing molecular oxygen O). 2 The method of claim 1 is to heat an organic lead salt in the presence of an oxidizing gas (e.g., a oxidizing agent) and carbon dioxide to form lead (II) oxide and convert the lead (II) oxide into lead carbonate. Thus, converting the organic lead salt into lead carbonate may include heating the organic lead salt in the presence of an oxidizing gas and carbon dioxide. Without being bound by theory, it is understood that heating the organic lead salt in the presence of an oxidizing agent will form beta lead (II) oxide. Those skilled in the art will recognize that beta lead (II) oxide may not be the only product formed. Beta lead (II) oxide reacts with carbon dioxide to form lead carbonate.

[0068] If the oxidant comprises a gas (eg, a gas containing molecular oxygen), the oxidant may be provided as a gas stream. The method may include contacting the organic lead salt with the oxidant stream.

[0069] The carbon dioxide may be provided as a carbon dioxide stream. The method may comprise contacting the lead (II) oxide with the carbon dioxide stream.

[0070] If the oxidant contains molecular oxygen (e.g., if air is used as the oxidant) and if forming lead carbonate comprises heating lead (II) oxide in the presence of carbon dioxide, the molar ratio of carbon dioxide to molecular oxygen may optionally be at least 10:1, optionally may be at least 12:1, optionally may be at least 15:1, optionally may be at least 18:1, optionally may be at least 20:1, optionally may be at least 25:1. For the avoidance of doubt, if air is used to provide the molecular oxygen, the amount of molecular oxygen may be determined based on air comprising 21% oxygen. The inventors have found that a relatively high ratio of carbon dioxide to molecular oxygen is effective in producing a high percentage of alpha lead oxide, particularly when lead citrate is heated in a gas mixture containing molecular oxygen (e.g., air) and carbon dioxide.

[0071] The molar ratio of carbon dioxide to molecular oxygen may optionally be no more than 250:1, optionally no more than 200:1, optionally no more than 150:1, optionally no more than 100:1.

[0072] PbOPbCO 3 The conversion to red lead may optionally include the conversion of PbOPbCO 3Convert PbOPbCO to alpha lead oxide, and convert alpha lead oxide to red lead. 3 The conversion to alpha lead oxide may include in a gas stream (optionally, the gas contains an oxidant, such as O 2 ) in the presence of PbOPbCO 3 Although the oxidant does not react with PbOPbCO 3 The reaction occurs, but the gas flow removes carbon dioxide that would otherwise react with the alpha lead oxide. The conversion of the alpha lead oxide to red lead may include the addition of an oxidizing agent, an optional oxidizing gas (e.g., containing molecular oxygen O 2 Alpha lead oxide is heated in the presence of a gas such as air.

[0073] PbOPbCO 3 The conversion to red lead may involve heating PbOPbCO at a sufficiently high temperature 3 Promote the formation of red lead. PbOPbCO 3 Heating may be at a temperature of at least 325° C., optionally at least 350° C., optionally at least 375° C., optionally at least 400° C., optionally at least 425° C. Applicants have found that heating to relatively high temperatures promotes the formation of red lead.

[0074] PbO 3 Heating may optionally be performed at a temperature not exceeding 500°C, optionally not exceeding 475°C, optionally not exceeding 450°C, optionally not exceeding 425°C.

[0075] PbO 3 The heating may be long enough to promote the formation of red lead. For example, PbOPbCO 3 Heating may be performed for at least 30 minutes, optionally at least 45 minutes, optionally at least 60 minutes. Applicants have found that the formation of red lead is relatively slow and requires prolonged heating, the duration of which depends to some extent on the temperature.

[0076] PbO 3 Heating may be performed at a temperature of 350°C to 400°C, optionally at a temperature of 375°C to 425°C, optionally for 30 to 90 minutes, optionally for 60 to 90 minutes.

[0077] The process can be carried out in a rotary furnace.

[0078] The organic lead salt may be as defined above in relation to the process of the first aspect of the invention.

[0079] Those skilled in the art will appreciate that the method of the present invention does not necessarily produce only red lead, and other components besides red lead may also be present. For example, α-lead oxide, β-lead oxide, metallic lead and Pb may be present. 2 O3 However, the composition produced by the method of the present invention may contain at least 50 wt% red lead, optionally at least 60 wt% red lead, optionally at least 70 wt% red lead, optionally at least 80 wt% red lead, optionally at least 90 wt% red lead, optionally at least 95 wt% red lead, optionally at least 98 wt% red lead by weight. For example, acid dissolution or X-ray diffraction can be used to measure the red lead content, as described above.

[0080] As described above, the method of the fifth aspect of the present invention can be used to prepare a composition containing red lead. According to the sixth aspect of the present invention, there is provided a composition containing red lead, which can be prepared by the method of the fifth aspect of the present invention, or is prepared by the method. Therefore, the composition can have any of the above features associated with the method of the fifth aspect of the present invention. The composition can contain, for example, at least 85wt% of red lead, optionally at least 90wt% of red lead.

[0081] The composition of the sixth aspect of the invention may have the features described above for the composition of the second aspect of the invention. For example, the composition of the sixth aspect of the invention may optionally include particles containing sub-particles. For example, the sub-particles may be protrusions.

[0082] According to a seventh aspect of the present invention, there is provided a method for preparing a 2 O 3 A method of making a composition, the method comprising: Conversion of organic lead salts into PbOPbCO 3 ;as well as PbOPbCO 3 Convert to Pb 2 O 3 .

[0083] Pb 2 O 3 (or lead trioxide) is well known to those skilled in the art.

[0084] Conversion of organic lead salts into PbOPbCO 3 Those features described above in relation to the method for forming red lead according to the fifth aspect of the present invention may be included.

[0085] PbOPbCO 3 Converted to Pb 2 O 3 Optionally, PbOPbCO 3 Conversion to alpha lead oxide, and conversion of alpha lead oxide to Pb 2 O 3 . PbOPbCO 3The conversion to alpha lead oxide may include in a gas stream (optionally, the gas contains an oxidant, such as O 2 ) in the presence of PbOPbCO 3 Although the oxidant does not react with PbOPbCO 3 The reaction occurs, but the gas flow removes the carbon dioxide that would otherwise react with the alpha lead oxide. 2 O 3 The oxidant may include an oxidizing agent, an optional oxidizing gas (e.g. containing molecular oxygen O 2 α-lead oxide is heated in the presence of a gas such as air. 3 Converted to Pb 2 O 3 The general method is to convert PbOPbCO 3 The method of converting to red lead is similar, but the method of obtaining Pb 2 O 3 The temperatures used are lower than those used to obtain red lead.

[0086] In the presence of an oxidant, PbOPbCO 3 can be heated at a sufficiently high temperature to promote the 2 O 3 The formation of PbOPbCO 3 The temperature may be at least 275° C., optionally at least 300° C., optionally at least 325° C., optionally at least 350° C. However, too high a temperature promotes the formation of red lead, so it is preferred to heat the lead carbonate to a temperature of no more than 400° C., optionally no more than 375° C., optionally no more than 350° C., optionally no more than 325° C.

[0087] PbO 3 The heating may be performed for at least 30 minutes, optionally at least 45 minutes, optionally at least 60 minutes, optionally at least 90 minutes. 3 The heating time may be no more than 300 minutes, optionally no more than 240 minutes, optionally no more than 180 minutes, optionally no more than 150 minutes, optionally no more than 120 minutes, optionally no more than 90 minutes. The applicant has found that Pb 2 O 3 The formation of red lead is relatively slow, especially at lower temperatures which are conducive to inhibiting the formation of red lead.

[0088] PbO 3 Heating may be performed at a temperature of 275°C to 350°C, optionally at a temperature of 275°C to 325°C, optionally for 30 to 180 minutes, optionally for 60 to 120 minutes.

[0089] The process can be carried out in a rotary furnace.

[0090] The organic lead salt may be as defined in the method of the first aspect of the invention.

[0091] Those skilled in the art will appreciate that the method of the present invention does not necessarily produce only Pb 2 O 3 , there may also be 2 O 3 For example, one or more of alpha lead oxide, beta lead oxide, metallic lead and red lead may be present. Specifically, alpha lead oxide and / or red lead may be present. However, the composition produced by the method of the present invention may contain at least 40 wt% by weight of Pb 2 O 3 , optionally at least 50 wt% Pb 2 O 3 , optionally at least 60 wt% Pb 2 O 3 For example, acid dissolution and X-ray diffraction can be used to measure Pb 2 O 3 Content, as described above.

[0092] As described above, the method of the seventh aspect of the present invention can be used to prepare 2 O 3 According to an eighth aspect of the present invention, there is provided a composition containing Pb 2 O 3 The composition can be prepared by the method of the seventh aspect of the present invention, or can be prepared by the method. The composition can have the above-mentioned characteristics related to the method of the sixth aspect of the present invention. The composition can contain, for example, at least 40wt% Pb 2 O 3 , optionally at least 60 wt% Pb 2 O 3 .

[0093] The composition of the eighth aspect of the invention may have the features described above for the composition of the second aspect of the invention. For example, the composition of the eighth aspect of the invention may optionally include particles containing sub-particles. For example, the sub-particles may be protrusions.

[0094] According to the ninth aspect of the present invention, there is provided a method for preparing a product containing the desired α lead oxide, β lead oxide, Pb 2 O 3 , red lead and metallic lead, the method comprising: Determine what is needed in the composition: alpha lead oxide, beta lead oxide, Pb 2 O 3 , red lead and metallic lead; selecting one or more reaction parameters from one or more heating temperatures, one or more heating durations, and one or more gas compositions based on the determination; The organic lead salt is heated according to one or more selected reaction parameters to form a desired α-lead oxide, β-lead oxide, Pb 2 O 3 , red lead and metallic lead.

[0095] The present inventors have discovered that the composition of the lead-containing composition can be controlled primarily by controlling the composition of the gas in which the organic lead salt is heated.

[0096] The method may include determining the desired alpha lead oxide, and the selection of one or more reaction parameters includes selecting a first gas composition, the first gas composition containing carbon dioxide and an oxidant, preferably containing molecular oxygen. The selection of one or more reaction parameters optionally includes selecting a second gas composition, the second gas composition containing an inert gas. The method may include heating the organic lead salt in the presence of the first gas composition. The method may include subsequent heating in the presence of the second gas composition. The method of the ninth aspect of the invention may have the characteristics of the method for preparing alpha lead oxide according to the first aspect of the invention.

[0097] The method may include determining the desired beta lead oxide, and the selection of one or more reaction parameters includes selecting a gas composition containing an oxidant, preferably molecular oxygen, optionally including air. The gas composition may contain an oxidant and an inert diluent. The method may include mixing the gas containing the oxidant with the inert diluent. The method may include heating the organic lead salt in the presence of the gas composition, optionally in the flow of the gas composition. The method of the ninth aspect of the invention may have the characteristics of the method for preparing beta lead oxide according to the third aspect of the invention.

[0098] The method may include determining the desired red lead, and the selection of one or more reaction parameters includes selecting a first gas composition containing carbon dioxide and an oxidant, preferably molecular oxygen. The selection of one or more reaction parameters optionally includes selecting a second gas composition containing an oxidant, such as O 2, and optionally excluding carbon dioxide. The selection of one or more reaction parameters may include selecting the temperature at which the second gas composition contacts the reagent. The temperature is optionally at least 350°C, optionally at least 375°C. The method may include heating the organic lead salt in the presence of the first gas composition. The method may include subsequently heating in the presence of the second gas composition, optionally at a selected temperature. The method of the ninth aspect of the invention may have the features of the method for preparing red lead according to the fifth aspect of the invention.

[0099] The method may include determining the required Pb 2 O 3 , and the selection of one or more reaction parameters includes selecting a first gas composition, the first gas composition containing carbon dioxide and an oxidant, preferably containing molecular oxygen. The selection of one or more reaction parameters optionally includes selecting a second gas composition, the second gas composition containing an oxidant, optionally containing O 2 , and optionally excluding carbon dioxide. The selection of one or more reaction parameters may include selecting the temperature at which the second gas composition contacts the reagent. The temperature is optionally at least 275°C and optionally not more than 375°C. The method may include heating the organic lead salt in the presence of the first gas composition. The method may include subsequently heating in the presence of the second gas composition, optionally at a selected temperature. The method of the ninth aspect of the invention may have the method of preparing Pb according to the seventh aspect of the invention. 2 O 3 Characteristics of the method.

[0100] The method may include determining the need for alpha lead oxide, beta lead oxide, Pb 2 O 3 , red lead and metallic lead.

[0101] The method may include determining the required amounts of the required components. For example, the method may include determining the required beta lead oxide and the required at least 5 wt % metallic lead. The selection of one or more parameters may include selecting a gas composition containing an oxidant, preferably containing molecular oxygen, optionally including air. The selection of one or more parameters may include selecting a temperature of at least 350° C. The gas composition may contain an oxidant and an inert diluent. The method may include mixing the gas containing the oxidant with the inert diluent. The method may include heating the organic lead salt in the presence of the gas composition at a selected temperature.

[0102] Those skilled in the art will recognize that the chemical composition of the synthesized composition need not be the same as the expected chemical composition. Those skilled in the art will recognize that, given the nature of chemical synthesis, the synthesized chemical composition may differ to a certain extent from the expected chemical composition.

[0103] The organic lead salt may be as defined in the method of the first aspect of the invention.

[0104] According to the tenth aspect of the present invention, there is provided a composition comprising α-lead oxide, β-lead oxide, metallic lead, Pb 2 O 3 and Pb 3 O 4 The composition comprises particles comprising sub-particles, the sub-particles optionally having an average maximum dimension of 10 to 300 nm. The sub-particles may be in the form of protrusions.

[0105] The inventors have found that a composition containing lead-based materials useful in the battery industry has advantageous properties (particularly a relatively high surface area) if the composition comprises relatively large particles which in turn comprise relatively small subparticles (optionally in the form of protrusions). As mentioned above in relation to the second aspect of the invention, subparticles are smaller than particles. Those skilled in the art will recognise that not all subparticles need to be in the form of protrusions. Thus, particles may include subparticles which are not in the form of protrusions. Thus, at least some of the subparticles may be in the form of protrusions.

[0106] The particles may be of any shape. For example, the composition may optionally include rod-shaped particles, and the protrusions are located on the rod-shaped particles. The rod-shaped particles may optionally have an average maximum dimension of 0.2 μm to 20 μm. For example, the composition may include spherical or sub-spherical particles.

[0107] The size of particles and subparticles may be measured using any suitable method, such as scanning electron microscopy.

[0108] The average maximum dimension of the subparticles may be calculated using at least 30% of the subparticles, optionally at least 40% of the subparticles, optionally at least 50% of the subparticles, optionally at least 60% of the subparticles, optionally at least 70% of the subparticles, optionally at least 80% of the subparticles by number.

[0109] When determining the average maximum dimension of the sub-particles, at least 30% of the particles, optionally at least 40% of the particles, optionally at least 50% of the particles, optionally at least 60% of the particles, optionally at least 70% of the particles, optionally at least 80% of the particles, optionally at least 90% of the particles by number may be used to determine the maximum dimension of the sub-particles.

[0110] When determining the average maximum dimension of the subparticles, at least 50% of the composition, optionally at least 60% of the composition, optionally at least 70% of the composition, optionally at least 80% of the composition, optionally at least 90% of the composition by mass may be used to determine the maximum dimension of the subparticles.

[0111] Optionally, at least 20% of the particles of the composition are rod-shaped particles. Optionally, at least 40%, optionally at least 50%, optionally at least 60%, optionally at least 70%, optionally at least 80%, optionally at least 90%, optionally at least 95% of the particles of the composition are rod-shaped.

[0112] Optionally, among the rod-shaped particles, optionally at least 50% by number have a maximum dimension of 0.2 μm to 20 μm, optionally at least 60% by number, optionally at least 70% by number, optionally at least 80% by number, optionally at least 90% by number have a maximum dimension of 0.2 μm to 20 μm.

[0113] As described above, the composition optionally includes rod-shaped particles. The average aspect ratio of the rod-shaped particles can be at least 1.5: 1, optionally at least 2.0: 1, optionally at least 3.0: 1. The average aspect ratio of the rod-shaped particles can optionally be no more than 20: 1, optionally no more than 15: 1, optionally no more than 10: 1, optionally no more than 7.5: 1, optionally no more than 5: 1.

[0114] Optionally, among the rod-shaped particles, optionally at least 50% by number, optionally at least 60% by number, optionally at least 70% by number, optionally at least 80% by number, optionally at least 90% by number have an aspect ratio of at least 1.5: 1, optionally at least 2.0: 1, optionally at least 3.0: 1. Optionally at least 50% by number, optionally at least 60% by number, optionally at least 70% by number, optionally at least 80% by number, optionally at least 90% by number have an aspect ratio of no more than 20: 1, optionally no more than 15: 1, optionally no more than 10: 1, optionally no more than 7.5: 1, optionally no more than 5: 1.

[0115] The BET surface area of ​​the composition (optionally measured using nitrogen, optionally at 77 K) is optionally at least 1.0 m 2 / g, optional at least 1.5m 2 / g, optional at least 2.0m 2 / g, optional at least 2.5m 2 / g, optional at least 3.0m 2 / g. BET surface area (optionally measured using nitrogen, optionally at 77K) is optionally not more than 10m 2 / g, optionally not more than 8m 2 / g, optionally not more than 6m 2 / g, optionally not more than 5m 2 / g.

[0116] The average maximum dimension of the subparticles may optionally be at least 10 nm, optionally at least 15 nm, optionally at least 20 nm, optionally at least 25 nm, optionally at least 30 nm, optionally at least 40 nm, optionally at least 50 nm. The average maximum dimension of the subparticles may optionally be no more than 300 nm, optionally no more than 250 nm, optionally no more than 200 nm, optionally no more than 150 nm, optionally no more than 100 nm. The average maximum dimension of the subparticles may be from 10 to 300 nm, optionally from 15 nm to 200 nm, optionally from 20 nm to 150 nm, optionally from 50 to 150 nm. The subparticles may be spherical or subspherical.

[0117] The composition has a pore volume, optionally determined by BJH analysis, optionally determined from BET data obtained using nitrogen, optionally at 77 K, optionally with a pore volume of at least 0.0050 cm 3 g -1 , optionally at least 0.0060 cm 3 g -1 , optionally at least 0.0070 cm 3 g -1 The pore volume is optionally not more than 0.025 cm 3 g -1 , optionally not more than 0.020 cm 3 g -1 , optionally not more than 0.015 cm 3 g -1 , optionally not more than 0.010 cm 3 g -1 , optionally not more than 0.0080 cm 3 g -1 , optionally not more than 0.0070 cm 3 g -1 .

[0118] The pore size of the composition as determined by adsorption measurements may optionally be at least Optionally at least Optionally at least Optionally at least Optionally at least Optionally at least Optionally at least The pore size determined by adsorption measurements may optionally be no greater than Optionally not more than Optionally not more than Optionally not more than Optionally not more than Optionally not more than Optionally not more than Optionally not more than Optionally not more than

[0119] The acid absorption of the composition may optionally be at least 200 mg of acid per gram of sample, optionally at least 220 mg of acid per gram of sample, optionally at least 240 mg of acid per gram of sample. The acid absorption may optionally be no more than 1000 mg of acid per gram of sample, optionally no more than 800 mg of acid per gram of sample, optionally no more than 600 mg of acid per gram of sample, optionally no more than 500 mg of acid per gram of sample, optionally no more than 400 mg of acid per gram of sample, optionally no more than 350 mg of acid per gram of sample, optionally no more than 300 mg of acid per gram of sample, and optionally no more than 280 mg of acid per gram of sample. The acid absorption may be determined using sulfuric acid, such as 16 wt % sulfuric acid.

[0120] The average maximum dimension of the subparticles may optionally be no more than three times the average minimum dimension of the subparticles. For example, the average "length" of the subparticles may be no more than three times the average "width" of the protrusions. The average maximum dimension of the subparticles may optionally be no more than 2.5 times, optionally no more than 2.0 times, optionally no more than 1.5 times the average minimum dimension of the subparticles.

[0121] Throughout this disclosure, if a subparticle is a protrusion, the protrusion may optionally be approximately spherical or partially spherical (eg, hemispherical).

[0122] The particles included in the composition may have a core portion rich in metallic lead and poor in oxides, and an outer portion rich in oxides. The weight percentage of metallic lead in the core portion is optionally greater than the weight percentage of metallic lead in the outer portion. The weight percentage of oxides in the core portion is optionally lower than the weight percentage of oxides in the outer portion. The inventors have found that the core portion of some particles is rich in metallic lead and has a low content of lead oxides, while the outer portion is rich in lead oxides. Such an arrangement is advantageous because the outer portion can effectively protect the core portion from oxidation when the composition is exposed to air. With respect to the composition of the outer portion, "lead oxides" include all lead oxides, including alpha lead oxide, beta lead oxide, red lead and Pb 2 O 3 .

[0123] The core portion may comprise at least 95 wt% metallic lead, optionally at least 96 wt% metallic lead, optionally at least 98 wt% metallic lead by weight.The core portion may be substantially free of lead oxide.

[0124] The outer part may contain alpha lead oxide, beta lead oxide, red lead and Pb 2 O 3 One or more of .

[0125] The core portion may be spherical or sub-spherical.

[0126] The average maximum dimension of the core portion may be at least 1 μm, optionally at least 2 μm, optionally at least 5 μm, optionally at least 10 μm. The average maximum dimension of the core portion may optionally be no more than 100 μm, optionally no more than 80 μm, optionally no more than 60 μm, optionally no more than 50 μm, optionally no more than 40 μm, optionally no more than 30 μm.

[0127] The volume of the core part is optionally greater than the volume of the outer part. The volume of the core part is optionally at least twice, optionally at least three times, optionally at least five times, optionally at least ten times, optionally at least fifteen times, optionally at least twenty times, optionally at least thirty times, optionally at least forty times, optionally at least fifty times, optionally at least one hundred times the volume of the outer part.

[0128] Those skilled in the art will recognize that the composition may contain lead in addition to alpha lead oxide, beta lead oxide, metallic lead, Pb 2 O 3 For example, the composition may contain other oxides of lead (e.g. Pb 12 O 19 ) and carbon. It is expected that these other components will account for a small proportion of the composition, for example, no more than 5wt% of the composition, optionally no more than 3wt%, optionally no more than 2wt%, optionally no more than 1wt%, optionally no more than 0.5wt%, optionally no more than 0.1wt%. Therefore, the composition optionally contains at least 95wt%, optionally at least 97wt%, optionally at least 98wt%, optionally at least 99wt%, optionally at least 99.5wt%, optionally at least 99.9wt% of alpha lead oxide, beta lead oxide, metallic lead, Pb 2 O 3 and one or more of red lead.

[0129] The composition may contain metallic lead. The composition may contain alpha lead oxide. The composition may contain beta lead oxide. The composition may contain Pb 2 O 3 The composition may contain Pb 3 O 4 .

[0130] The composition may contain α-lead oxide, β-lead oxide, metallic lead, Pb 2 O 3 and Pb 3 O 4For example, the composition may contain metallic lead and one or both of alpha lead oxide and beta lead oxide. The composition may contain alpha lead oxide and beta lead oxide.

[0131] The composition may contain, for example, at least 1 wt% of metallic lead, optionally at least 2 wt%, optionally at least 3 wt%, optionally at least 5 wt%, optionally at least 8 wt%, optionally at least 10 wt%, optionally at least 15 wt%, optionally at least 20 wt%. The composition may contain, for example, no more than 40 wt% of metallic lead, optionally no more than 35 wt% of metallic lead, optionally no more than 30 wt% of metallic lead, optionally no more than 25 wt% of metallic lead, optionally no more than 20 wt% of metallic lead. It may be advantageous for the composition to contain a certain amount of metallic lead, particularly if the composition also contains alpha lead oxide and / or beta lead oxide.

[0132] The composition is basically composed of alpha lead oxide, beta lead oxide, metal lead, Pb 2 O 3 and one or more of red lead.

[0133] The composition may contain at least 98.0 wt% alpha lead oxide, optionally at least 98.5 wt%, optionally at least 99.0 wt%, optionally at least 99.5 wt% alpha lead oxide. The composition may contain no more than 99.9 wt% alpha lead oxide, optionally no more than 99.8 wt% alpha lead oxide, optionally no more than 99.7 wt% alpha lead oxide, optionally no more than 99.6 wt% alpha lead oxide, optionally no more than 99.5 wt% alpha lead oxide.

[0134] The composition may contain, optionally, at least 40 wt% alpha lead oxide, optionally, at least 50 wt% alpha lead oxide, optionally, at least 55 wt% alpha lead oxide, optionally, at least 60 wt% alpha lead oxide, optionally, at least 65 wt% alpha lead oxide, optionally, at least 70 wt% alpha lead oxide, optionally, at least 75 wt% alpha lead oxide.

[0135] The composition may contain, optionally, no more than 95 wt% alpha lead oxide, optionally no more than 90 wt% alpha lead oxide, optionally no more than 85 wt% alpha lead oxide, optionally no more than 80 wt% alpha lead oxide, optionally no more than 75 wt% alpha lead oxide, optionally no more than 70 wt% alpha lead oxide. Applicants have found that it may be beneficial for the composition to contain a substantial amount of alpha lead oxide, optionally in the presence of metallic lead.

[0136] The composition may contain, optionally, at least 40 wt% beta lead oxide, optionally, at least 50 wt% beta lead oxide, optionally, at least 55 wt% beta lead oxide, optionally, at least 60 wt% beta lead oxide, optionally, at least 65 wt% beta lead oxide, optionally, at least 70 wt% beta lead oxide, optionally, at least 75 wt% beta lead oxide.

[0137] The composition may contain, optionally, no more than 95 wt% beta lead oxide, optionally no more than 90 wt% beta lead oxide, optionally no more than 85 wt% beta lead oxide, optionally no more than 80 wt% beta lead oxide, optionally no more than 75 wt% beta lead oxide, optionally no more than 70 wt% beta lead oxide. Applicants have found that it may be beneficial to contain a substantial amount of beta lead oxide in the composition, optionally in the presence of metallic lead.

[0138] The composition may contain, optionally, a total amount of at least 40 wt% of beta lead oxide and alpha lead oxide, optionally a total amount of at least 50 wt% of beta lead oxide and alpha lead oxide, optionally a total amount of at least 55 wt% of beta lead oxide and alpha lead oxide, optionally a total amount of at least 60 wt% of beta lead oxide and alpha lead oxide, optionally a total amount of at least 65 wt% of beta lead oxide and alpha lead oxide, optionally a total amount of at least 70 wt% of beta lead oxide and alpha lead oxide, optionally a total amount of at least 75 wt% of beta lead oxide and alpha lead oxide.

[0139] The composition may contain, optionally, not more than 95% by weight of beta lead oxide and alpha lead oxide in total, optionally not more than 90% by weight of beta lead oxide and alpha lead oxide in total, optionally not more than 85% by weight of beta lead oxide and alpha lead oxide in total, optionally not more than 80% by weight of beta lead oxide and alpha lead oxide in total, optionally not more than 75% by weight of beta lead oxide and alpha lead oxide in total, optionally not more than 70% by weight of beta lead oxide and alpha lead oxide in total. Applicants have found that it may be beneficial for the composition to contain substantial amounts of beta lead oxide and alpha lead oxide, optionally in the presence of metallic lead.

[0140] The composition may contain 50-80 wt% alpha lead oxide and 10-20 wt% metallic lead. The composition may contain 60-80 wt% alpha lead oxide, optionally 70-80 wt% alpha lead oxide, optionally 75-80 wt% alpha lead oxide. The composition may contain 10-15 wt% metallic lead or 15-20 wt% metallic lead.

[0141] The composition may contain 50-80 wt% beta lead oxide and 10-20 wt% metallic lead. The composition may contain 60-80 wt% beta lead oxide, optionally 70-80 wt% beta lead oxide, optionally 75-80 wt% beta lead oxide. The composition may contain 10-15 wt% metallic lead or 15-20 wt% metallic lead.

[0142] The composition may contain at least 98.0 wt% beta lead oxide, optionally at least 98.5 wt%, optionally at least 99.0 wt%, optionally at least 99.5 wt% beta lead oxide. The composition may contain no more than 99.9 wt% beta lead oxide, optionally no more than 99.8 wt% beta lead oxide, optionally no more than 99.7 wt% beta lead oxide, optionally no more than 99.6 wt% beta lead oxide, optionally no more than 99.5 wt% beta lead oxide.

[0143] The composition may contain at least 98.0 wt% Pb 3 O 4 , optionally at least 98.5 wt %, optionally at least 99.0 wt %, optionally at least 99.5 wt % Pb 3 O 4 The composition may contain no more than 99.9 wt% of Pb 3 O 4 , optionally not more than 99.8 wt% Pb 3 O 4 , optionally not more than 99.7 wt% Pb 3 O 4 , optionally not more than 99.6 wt% Pb 3 O 4 , optionally not more than 99.5 wt% Pb 3 O 4 .

[0144] The composition may contain at least 40 wt% Pb 2 O 3 , optionally at least 50 wt% Pb 2 O 3 , optionally at least 60 wt% Pb 2 O 3 , optionally at least 70 wt% Pb 2 O 3 , optionally at least 80 wt% Pb 2 O 3 , optionally at least 90 wt% Pb 2 O 3 , optionally at least 95 wt% Pb 2 O 3, optionally at least 98 wt% Pb 2 O 3 .

[0145] The composition of the tenth aspect of the present invention can be prepared by the method of the first aspect, the third aspect, the fifth aspect, the seventh aspect and the ninth aspect of the present invention, and therefore can have one or more characteristics of these aspects of the present invention. On the contrary, the method of the first aspect, the third aspect, the fifth aspect, the seventh aspect and the ninth aspect of the present invention can include one or more characteristics of the composition of the tenth aspect of the present invention. In addition, the composition of the tenth aspect of the present invention can have one or more characteristics of the second aspect, the fourth aspect, the sixth aspect and the eighth aspect of the present invention. On the contrary, the composition of the second aspect, the fourth aspect, the sixth aspect and the eighth aspect of the present invention can have one or more characteristics of the composition of the tenth aspect of the present invention.

[0146] According to the eleventh aspect of the present invention, there is provided a composition comprising α-lead oxide, β-lead oxide, metallic lead, Pb 2 O 3 and Pb 3 O 4 The composition may be a composition of one or more particles comprising a core portion rich in metallic lead and poor in oxides and an outer portion rich in oxides. The outer portion rich in oxides may be deficient in metallic lead. The inventors have found that the core portion of some particles is rich in metallic lead and has a low content of lead oxides, while the outer portion is rich in lead oxides. Such an arrangement is advantageous because the outer portion can effectively protect the core portion from oxidation when the composition is exposed to air. Without being bound by theory, it is foreseeable that a battery made from such a composition may have a longer cycle life because the outer portion protects the core portion from sulfation.

[0147] The core portion may contain at least 95 wt% metallic lead, optionally at least 96 wt% metallic lead, optionally at least 98 wt% metallic lead.The core portion may be substantially free of lead oxide.

[0148] The outer part may contain alpha lead oxide, beta lead oxide, red lead and Pb 2 O 3 One or more of .

[0149] The core portion may be spherical or sub-spherical.

[0150] The average maximum dimension of the core portion may be optionally at least 1 μm, optionally at least 2 μm, optionally at least 5 μm, optionally at least 10 μm. The average maximum dimension of the core portion may optionally be no more than 100 μm, optionally no more than 80 μm, optionally no more than 60 μm, optionally no more than 50 μm, optionally no more than 40 μm, optionally no more than 30 μm.

[0151] Those skilled in the art will recognize that the composition may contain lead in addition to alpha lead oxide, beta lead oxide, metallic lead, Pb 2 O 3 For example, the composition may contain other oxides of lead (e.g. Pb 12 O 19 ) and carbon. It is expected that these other components will account for a minor proportion of the composition, for example, no more than 5wt% of the composition, optionally no more than 3wt%, optionally no more than 2wt%, optionally no more than 1wt%, optionally no more than 0.5wt%, optionally no more than 0.1wt%. Therefore, the composition optionally contains at least 95wt%, optionally at least 97wt%, optionally at least 98wt%, optionally at least 99wt%, optionally at least 99.5wt%, optionally at least 99.9wt% of alpha lead oxide, beta lead oxide, metallic lead, Pb 2 O 3 and one or more of red lead.

[0152] The composition of the eleventh aspect of the present invention can be prepared by the method of the first aspect, the third aspect, the fifth aspect, the seventh aspect and the ninth aspect of the present invention. The composition of the eleventh aspect of the present invention can have the above-mentioned characteristics related to the composition of the second aspect, the fourth aspect, the sixth aspect, the eighth aspect and the tenth aspect of the present invention.

[0153] In some embodiments, the compositions of the second, fourth, sixth, eighth, tenth and / or eleventh aspects of the invention are processed into panels, for example, using methods well known to those skilled in the art.

[0154] According to a twelfth aspect of the present invention, there is provided a method for making a lead-acid battery plate, comprising combining the composition of the second, fourth, sixth, eighth, tenth and / or eleventh aspects of the present invention with one or more battery paste additives and an acid to form a paste. Sulfuric acid is typically used as the acid to convert the lead oxide in the composition into PbSO 4 Suitable battery paste additives include those listed above, including metal compounds, insoluble carbon, barium sulfate and fibers. The paste is then applied to a grid (usually a lead alloy grid) and allowed to cure to form a plate. The method of making lead-acid battery plates can be applied to thin plate pure lead (TPPL) batteries.

[0155] According to the thirteenth aspect of the present invention, there is provided a battery plate which can be manufactured by the method of the eleventh aspect of the present invention, or a battery plate manufactured by the method of the eleventh aspect of the present invention. The lead-acid battery plate may be suitable for a thin plate pure lead (TPPL) battery.

[0156] Conversely, the solar panels can also be incorporated into lead-acid batteries. The solar panels can be incorporated into lead-acid batteries using known methods.

[0157] Therefore, according to a fourteenth aspect of the present invention, there is provided a lead acid battery comprising one or more battery plates according to the twelfth aspect of the present invention. The battery may be a thin plate pure lead (TPPL) battery.

[0158] The lead-acid battery of the fourteenth aspect of the present invention may include a battery housing in which one or more battery plates of the thirteenth aspect of the present invention are disposed. The housing may contain battery acid, such as sulfuric acid. Once the battery is assembled, the lead acid in the battery plates, such as PbSO 4 (and basic lead sulfate) are converted to PbO on the positive plate 2 , converted into metallic lead on the negative plate.

[0159] Of course, it should be understood that features described with respect to one aspect of the invention may be incorporated into other aspects of the invention. For example, the method of the invention may include any features described with reference to the apparatus of the invention, and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0160] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0161] Figure 1 A schematic diagram showing an example of a method for preparing alpha lead oxide according to a first embodiment of the present invention;

[0162] Figure 2A shows a low-magnification scanning electron microscope image of an example of a composition containing alpha lead oxide according to the second aspect and the tenth aspect of the present invention;

[0163] Figure 2B High-magnification scanning electron microscope images showing examples of compositions containing alpha lead oxide according to the second and tenth aspects of the present invention;

[0164] Figure 3 A schematic diagram showing an example of a method for preparing a composition containing beta lead oxide according to another embodiment of the present invention;

[0165] Figure 4Ashows low-magnification scanning electron microscope images of examples of compositions containing beta lead oxide according to the fourth and tenth aspects of the present invention;

[0166] Figure 4B High-power scanning electron microscope images showing examples of compositions containing beta lead oxide according to the fourth and tenth aspects of the present invention;

[0167] Figure 5 A schematic diagram showing an example of a method for preparing red lead according to another embodiment of the present invention;

[0168] Fig. 6A A low-magnification scanning electron microscope image showing an example of a composition containing red lead according to the sixth and tenth aspects of the present invention;

[0169] Figure 6B High-power scanning electron microscope images showing examples of the red lead-containing compositions according to the sixth and tenth aspects of the present invention;

[0170] Figure 7 Another embodiment of the present invention is to prepare Pb 2 O 3 A schematic diagram of an example of a method;

[0171] Fig. 8A The Pb-containing 2 O 3 A low magnification scanning electron microscope image of an example of a composition of;

[0172] Figure 8B The Pb-containing 2 O 3 High magnification scanning electron microscope images of examples of compositions;

[0173] Fig. 9 A schematic diagram showing an example of a method for preparing a composition containing desired components according to another embodiment of the present invention;

[0174] Fig.10 A schematic diagram showing an example of a method for manufacturing a solar panel according to yet another embodiment of the present invention;

[0175] Fig.11 is a simplified perspective view of a battery according to an embodiment of the present invention;

[0176] Fig. 12A and Fig. 12B A low-magnification scanning electron microscope image showing an example of a core of particles of a composition containing alpha lead oxide obtained according to the second and tenth aspects of the present invention;

[0177] Fig.13 The figure shows the metal lead content of the lead oxide powder sample according to the present invention after being exposed to air for a period of time compared with that of the conventional lead oxide;

[0178] Fig.14A and Fig. 14B Low-magnification and high-magnification scanning electron microscope images of examples of particles of the lead oxide-containing composition according to the tenth aspect of the present invention are shown, respectively. DETAILED DESCRIPTION

[0179] A method of forming a composition containing alpha lead oxide.

[0180] The composition containing α-lead oxide was synthesized by the following method. 30 g of lead citrate (Pb 3 (C 6 H 5 O 7 ) 2 ·3H 2 O) is placed in a 4-liter rotary furnace. The preparation of lead citrate is as described in WO2008 / 056125. Scanning electron microscopy shows that lead citrate is elongated, with a particle length of about 10 to 40 μm and a particle width of about 2 to 4 μm. X-ray diffraction confirms that the lead citrate is indeed lead citrate. A mixture of air (18 L / hr) and carbon dioxide (18 to 25 L / hr) is passed into lead citrate, while lead citrate is heated to 350°C, and then lead citrate is heated at 350°C for a known first period of time of 1 hour 45 minutes to 2 hours. After this first period, a nitrogen flow (12 L / hr) is passed into the material in the rotary furnace for a known second period of time of 3 to 30 minutes. The rotary furnace is then cooled to room temperature, and nitrogen is passed into the rotary furnace (12 L / hr). The rotary furnace is always rotated at a speed of 20 rpm. The resulting composition is then analysed using X-ray diffraction and acid dissolution techniques to determine the presence and relative amounts of the various components within the composition, such as alpha lead oxide, beta lead oxide, red lead and metallic lead as described above in relation to the process of the first aspect of the invention.

[0181] Table 1 below shows how the composition varies with process conditions. Residence time 1 refers to the time that the lead citrate is heated and exposed to air and carbon dioxide. Residence time 2 refers to the time that the contents of the rotary kiln are heated in the presence of nitrogen. In Comparative Examples 1 (CEx1) to 4 (CEx4), a mixture of air and carbon dioxide is always passed into the rotary kiln. Table 1 - Formation of compositions containing alpha lead oxide It should be noted that the acid dissolution method was not used to measure Pb 3 O 2 CO3 In Table 1, "P" means "present" and "D" means "significant".

[0182] No carbon or red lead was found in the compositions of Examples 1 to 8. In the composition of Example 9, 2 wt% carbon was found.

[0183] Examples 1 to 9 demonstrate that alpha lead oxide can be prepared by heating lead citrate in the presence of air and carbon dioxide and then heating the reaction product in the presence of nitrogen.

[0184] Without being bound by theory, it is understood that the following reactions occur: Pb 3 (C 6 H 5 O 7 ) 2 3H 2 O (s) +9O 2(g) → 3βPbO (s) +12CO 2(g) + 8H 2 O (g) --------- (1) βPbO (s) + CO 2(g) → PbCO 3 (s) --------- (2) 2αPbO (s) + PbCO 3 (s) → 2PbOPbCO 3 (s) --------- (4) 2PbO PbCO 3(s) + N 2(g) → 3αPbO (s) +CO 2(g) + N 2(g) --------- (5)

[0185] refer to Figure 1 Without being bound by theory, it is contemplated that the method 100 for forming alpha lead oxide from lead citrate comprises: 101 converting the lead citrate into 2PbOPbCO 3 , and 102 will 2PbOPbCO 3It is expected that oxygen in the air will react with the lead citrate to form lead oxide (probably beta lead oxide), which will then react with carbon dioxide to form lead carbonate. Heating the lead carbonate will form alpha lead oxide, which will react with lead carbonate to form 2PbOPbCO 3 2PbOPbCO is heated in an inert gas (nitrogen in this case) 3 Alpha lead oxide is formed.

[0186] To promote the formation of lead carbonate, it seems to be beneficial to provide excess carbon dioxide. Heating PbOPbCO in an inert atmosphere 3 A sufficiently long time is also beneficial to promote the formation of alpha lead oxide. It is expected that the use of a carbon dioxide flow rate of 250L / hr will result in the formation of carbon because the oxygen content is relatively low and the carbon dioxide content is relatively high.

[0187] Examples 1 to 9 in Table 1 show that compositions containing a high percentage of alpha lead oxide can be produced. In addition, Examples 1 to 9 and Examples 3 to 9 specifically show that the relative amounts of alpha lead oxide and beta lead oxide can be controlled by controlling the relative amounts of air and carbon dioxide.

[0188] The scanning electron microscope image of the composition of Example 9 is as follows: Figure 2A and Figure 2B The composition comprises Figure 2A Large, elongated particles 150, 151, 152 are visible in the granules. The shape and size of these particles are similar to the lead citrate particles used to make alpha lead oxide. The average length of these particles exceeds 5 μm and the average width is about 1 to 2 μm. The surface of the particles appears rough and smaller sub-particles can be seen on the surface of the particles. Smaller sub-particles 160, 161, 162 with an average maximum size of about 50 to 200 nm can be seen.

[0189] A method of forming a composition containing beta lead oxide.

[0190] The composition containing β-lead oxide was synthesized by the following method. 30 g of lead citrate (Pb 3 (C 6 H 5 O 7 ) 2 ·3H 20) is placed in a 4-liter rotary furnace. The preparation of lead citrate is as described in WO2008 / 056125. Scanning electron microscopy shows that lead citrate is elongated, with a particle length of about 10 to 40 μm and a particle width of about 2 to 4 μm. X-ray diffraction confirms that the lead citrate is indeed lead citrate. A mixture of air (6 to 100 L / hr) and nitrogen (12 L / hr) is passed into lead citrate, while lead citrate is heated to 350°C, and then lead citrate is heated at 350°C for 2 hours. The rotary furnace is then cooled to room temperature, and the same nitrogen and air mixture is passed into the rotary furnace. The rotary furnace is always rotated at a speed of 20 rpm. The resulting composition is then analyzed using X-ray diffraction and acid dissolution techniques to determine the presence and relative content of various components (such as the above-mentioned α-lead oxide, β-lead oxide, red lead and metallic lead) in the composition.

[0191] Table 2 below shows how the composition varies with process conditions. Table 2 - Formation of compositions containing beta lead oxide

[0192] In Example 19, there was no gas flow during the cooling phase, i.e., after exposure to the air and nitrogen mixture for two hours at 350° C. In Examples 20 and 21, nitrogen was omitted from the gas mixture, and as in Example 19, there was no gas flow during the cooling phase, i.e., after exposure to air for two hours at 350° C. In Example 22, nitrogen was omitted from the gas mixture, but in contrast to Examples 19 to 21, the nitrogen flow rate during the cooling phase was 12 L / hr.

[0193] Examples 10 to 22 demonstrate that controlled production of lead beta oxide can be achieved by heating lead citrate in an air stream. Figure 3 Without being bound by theory, it is contemplated that the method 200 of forming beta lead oxide from lead citrate comprises: heating 201 the lead citrate in the presence of an oxidizing agent (in this case, oxygen in air).

[0194] Examples 10 to 16 demonstrate that the use of high flow rates of air promotes the formation of beta lead oxide and metallic lead, as well as some alpha lead oxide. As the amount of air is reduced, the amount of beta lead oxide increases and metallic lead decreases. Examples 10 to 16 demonstrate that the amount of metallic lead in the composition can be controlled by controlling the relative amounts of air and nitrogen.

[0195] Examples 13, 17 and 18 show that the amount of metallic lead increases as the temperature at which the lead citrate is exposed to air and nitrogen increases from 300° C. to 400° C. In addition, scanning electron microscope images show that the composition produced by heating to 300° C. includes smaller subparticles having a size of about 50 μm, while the composition produced by heating to 400° C. includes larger subparticles having a size of several hundred microns.

[0196] Without being bound by theory, the expected reaction mechanism is as follows: Pb 3 (C 6 H 5 O 7 ) 2 3H 2 O (s) +9O 2(g) → 3βPbO (s) +12CO 2(g) + 8H 2 O (g) --------- (6)

[0197] The scanning electron microscope image of the composition of Example 13 is as follows: Figure 4A and Figure 4B The composition comprises Figure 4A Large, elongated particles 250, 251, 252 are visible in the granules. The shape and size of these particles are similar to the lead citrate particles used to make alpha lead oxide. The average length of these particles exceeds 5 μm and the average width is about 1 to 2 μm. The surface of the particles appears rough and smaller sub-particles can be seen on the surface of the particles. Smaller sub-particles 260, 261, 262 with an average maximum size of about 50 to 200 nm can be seen.

[0198] A method of forming a composition containing red lead.

[0199] The composition containing red lead was synthesized by the following method. 30 g of lead citrate (Pb 3 (C 6 H 5 O 7 ) 2 ·3H 2O) is placed in a 4-liter rotary furnace. The preparation of lead citrate is as described in WO2008 / 056125. Scanning electron microscopy shows that lead citrate is elongated, with a particle length of about 10 to 40 μm and a particle width of about 2 to 4 μm. X-ray diffraction confirms that the lead citrate is indeed lead citrate. A mixture of air (18 L / hr) and carbon dioxide (200 L / hr) is passed into the lead citrate, while the lead citrate is heated to 350°C, and then the lead citrate is heated at 350°C for 2 hours. After this first period, an air stream (200 L / hr) is passed into the material in the rotary furnace for a known second period of 30 or 60 minutes. The rotary furnace is then cooled to room temperature and air is passed into the rotary furnace (200 L / hr). The rotary furnace is always rotated at a speed of 20 rpm. The resulting composition is then analyzed using X-ray diffraction and acid dissolution techniques to determine the presence and relative amounts of the various components within the composition (eg, alpha lead oxide, beta lead oxide, red lead, and metallic lead as described above).

[0200] Table 3 below shows how the composition varies with process conditions. Residence time 2 is the duration of heating in the air stream. Residence temperature is the temperature at which the product is heated in the air stream. Table 3 - Formation of compositions containing red lead

[0201] Examples 23 to 27 demonstrate that red lead and compositions having a high percentage of red lead can be prepared by heating lead citrate in a stream of air and carbon dioxide and then heating the reaction product in a stream of air. Using higher temperatures when heating in air promotes the formation of red lead. Figure 5 Without being bound by theory, it is contemplated that the method 300 for forming red lead from lead citrate comprises: 301 converting lead citrate into PbOPbCO 3 , and 302 will PbOPbCO 3 Transformed into red lead.

[0202] Without being bound by theory, the following reaction occurs. Pb 3 (C 6 H 5 O 7 ) 2 3H 2 O (s) +9O 2(g) → 3βPbO (s) +12CO 2(g) + 8H 2 O (g) --------- (1) βPbO (s) + CO2(g) → PbCO 3 (s) --------- (2) 2αPbO (s) + PbCO 3 (s) → 2PbOPbCO 3 (s) --------- (4) 2PbOPbCO 3(s) → 3αPbO (s) + CO 2(g) --------- (7) 3αPbO (s) + 1 / 2O 2(g) → Pb 3 O 4(s) --------- (8) 2PbO PbCO 3(s) + O 2(g) → Pb 3 O 4(s) + CO 2(g) --------- (11)

[0203] 301Conversion of lead citrate to PbOPbCO 3 Including: heating lead citrate to form β-lead oxide, which reacts with carbon dioxide to form lead carbonate. Lead carbonate decomposes when heated to form α-lead oxide, which reacts with lead carbonate to form PbOPbCO 3 Heating PbOPbCO in an air stream 3 Alpha lead oxide will be formed, which reacts with oxygen to form red lead.

[0204] The scanning electron microscope image of the composition of Example 27 is as follows: Fig. 6A and Figure 6B The composition comprises Fig. 6A Large, elongated particles 350, 351, 352 are visible in the graphite. The shape and size of these particles are similar to the lead citrate particles used to make alpha lead oxide. The average length of these particles exceeds 5 μm and the average width is about 1 to 2 μm. The surface of the particles appears rough and smaller sub-particles can be seen on the surface of the particles. Smaller sub-particles 360, 361, 362 with an average maximum dimension of about 50 to 100 nm can be seen.

[0205] Formation of Pb 2 O 3 Composition method

[0206] The Pb-containing 2 O 3 30 grams of lead citrate (Pb 3 (C 6 H 5 O 7 ) 2 ·3H 2 O) is placed in a 4-liter rotary furnace. The preparation of lead citrate is as described in WO2008 / 056125. Scanning electron microscopy shows that lead citrate is elongated, with a particle length of about 10 to 40 μm and a particle width of about 2 to 4 μm. X-ray diffraction confirms that the lead citrate is indeed lead citrate. A mixture of air (18 L / hr) and carbon dioxide (200 L / hr) is passed into the lead citrate, while the lead citrate is heated to 350°C, and then the lead citrate is heated at 350°C for 2 hours. After this first period, an air flow (30 to 200 L / hr) is passed into the material in the rotary furnace at a temperature of 300°C or 350°C for a second period of 30 to 120 minutes. The rotary furnace is then cooled to room temperature and air flow is passed into the rotary furnace (200 L / hr). The rotary furnace is always rotated at a speed of 20 rpm. The resulting composition is then analyzed using X-ray diffraction and acid dissolution techniques to determine the presence and relative amounts of the various components within the composition (eg, alpha lead oxide, beta lead oxide, red lead, and metallic lead as described above).

[0207] Table 4 shows how the composition varies with processing conditions. Table 4 - Contains Pb 2 O 3 The formation of the composition

[0208] The temperatures indicated in Table 4 are the temperatures when the contents in the rotary furnace are exposed to air. The times indicated in Table 4 are the times when the contents in the rotary furnace are exposed to air.

[0209] Examples 28 to 36 demonstrate that by heating lead citrate in a stream of air and carbon dioxide and then heating the reaction product in a stream of air, preferably at relatively low temperatures (300° C. appears to be preferred in this case), it is possible to prepare a mixture having a high percentage of Pb 2 O 3 When heated in air, a higher temperature promotes the formation of red lead, while a lower temperature promotes the formation of Pb 2 O 3 formation.

[0210] refer to Figure 7Without being bound by theory, it is contemplated that the method 400 for forming red lead from lead citrate comprises: 401 converting lead citrate into PbOPbCO 3 , and 402 will PbOPbCO 3 Converted to Pb 2 O 3 . 401Conversion of lead citrate to PbOPbCO 3 Including: heating lead citrate to form β-lead oxide, which reacts with carbon dioxide to form lead carbonate. Lead carbonate decomposes when heated to form α-lead oxide, which reacts with lead carbonate to form PbOPbCO 3 Heating PbOPbCO in an air stream 3 It will form alpha lead oxide, which reacts with oxygen to form Pb 2 O 3 .

[0211] Without being bound by theory, the following reaction occurs. Pb 3 (C 6 H 5 O 7 ) 2 3H 2 O (s) +9O 2(g) → 3βPbO (s) +12CO 2(g) + 8H 2 O (g) --------- (1) βPbO (s) + CO 2(g) → PbCO 3 (s) --------- (2) 2αPbO (s) + PbCO 3 (s) → 2PbOPbCO 3 (s) --------- (4) 2PbOPbCO 3(s) → 3αPbO (s) +CO 2(g) --------- (9) 2αPbO (s) + O 2(g) → Pb 2 O 3(s) --------- (10) PbO PbCO 3(s) + 1 / 2O 2(g) → Pb 2 O 3(s) + CO 2(g) --------- (11)

[0212] The scanning electron microscope image of the composition of Example 36 is as follows: Fig. 8A and Figure 8B The composition comprises Fig. 6A Large, elongated particles 450, 451, 452 are visible in the granules. The shape and size of these particles are similar to the lead citrate particles used to make alpha lead oxide. The average length of these particles is over 5 μm and the average width is about 1 to 2 μm. The surface of the particles appears rough and smaller sub-particles can be seen on the surface of the particles. Smaller sub-particles 460, 461, 462 with an average maximum dimension of about 50 to 100 nm can be seen.

[0213] The present invention is to provide a mixture of α-lead oxide, β-lead oxide, red lead and Pb 2 O 3 The compositions of the samples were determined to determine their BET surface area, pore volume and pore size. These were performed using a sample size of about 0.55 to 0.60 g, a bath temperature of 77 K and N 2 Determined as an analytical adsorbent. Table 5 - Some characteristics of the compositions according to the invention

[0214] The structures of beta lead oxide according to the fourth, tenth and eleventh aspects of the present invention were studied. The beta lead oxide of the present invention and conventional ball-milled lead oxide were relatively evenly covered on an adhesive carbon tape. The powdered lead oxide was then pressed so that the powder was firmly embedded in the tape. One drop of 1wt% acetic acid solution was added to slowly dissolve the PbO. After 30 seconds, the excess solution was removed with dry paper. The process of wetting with acetic acid and removing the excess solution was repeated four times. The remaining material was then rinsed four times with a drop of distilled water.

[0215] Fig. 12A and Fig. 12BThe particles remaining after the particles were exposed to acetic acid are shown. The remaining particles are essentially spherical or sub-spherical (essentially similar to a sphere) with a diameter of about 15 to 30 μm. Each remaining particle is essentially the core of the original particle. Given that a 1wt% acetic acid solution will only dissolve PbO and not Pb, the core is essentially composed of metallic lead. The outer region containing lead oxide has been dissolved by acetic acid. This demonstrates that the structure of the lead oxide contains a metallic lead core covered by an outer region of lead oxide. Such a structure is beneficial because the lead oxide can protect the metallic lead inside from oxidation when the composition is exposed to a potentially oxidizing environment (such as air).

[0216] One of the main properties measured by battery manufacturers to determine the performance of lead oxide is the amount of acid absorption. This paper studies the Fig. 12A and Fig. 12B The acid absorption properties of the above materials were compared with those of conventional ball-milled and Barton pot lead oxide. 22 g (20 mL) of 16 wt% sulfuric acid solution was prepared and cooled to room temperature. Then 10 g of lead oxide was added in an insulated container with stirring at 350 rpm. The suspension was left to react for 20 minutes before analysis. The unreacted H 2 SO 4 To determine H 2 SO 4 The amount of lead oxide absorbed is also related to the temperature rise in the suspension during the reaction. The mass percentage of lead oxide reacted is also determined. Button Pot ball milling βPbO of the present invention αPbO of the present invention <![CDATA[Acid absorption (mg H 2 SO 4 / g sample)]]> 150.8 184.9 232.6 258.9 Temperature rise(℃) 11.35 12.5 17.1 17.7 Mass fraction of lead oxide reacted (wt%) 34％ 42％ 52.9％ 58.9％ Table 6 - Acid Absorption Properties of Alpha Lead Oxide and Beta Lead Oxide of the Invention

[0217] The data in Table 6 show that the acid absorption characteristics of the alpha lead oxide and beta lead oxide of the present invention are superior to those of the conventional barton pot and ball milled lead oxide. In addition, the mass percentage of lead oxide reacted in the alpha lead oxide and beta lead oxide of the present invention is much higher than that of conventional lead oxide.

[0218] The surface area and pore volume of the materials studied in Table 6 were measured and are shown in Table 7. Button Pot ball milling βPbO αPbO <![CDATA[Specific surface area BET (m 2 .g -1 )]]> 0.44 1.34 1.08 1.96 <![CDATA[Pore volume (cm 3 .g -1 )]]> 0.00175 0.004478 0.00620 0.011 Table 7 - Surface area and pore volume of alpha lead oxide and beta lead oxide of the present invention

[0219] Researched Fig. 12A and Fig. 12B The stability of the metallic lead in the above materials is determined by the reaction with an acid or a base. The metallic lead content (x) of the lead oxide of the present invention is compared with the known Barton pot (o) and ball milled (+) lead oxides. The metallic lead content is determined by the reaction with an acid or a base. Fig.13 The change of metallic lead content over time is shown. Fig.13It is obvious that the loss rate of metallic lead in the lead oxide of the present invention is much lower than that in the conventional lead oxide.

[0220] Fig.14A and Fig. 14B A scanning electron microscope image of an example of a composition according to the tenth aspect of the invention is shown in FIG. Fig.14A is a low magnification image showing an agglomerated particle AG having a channel network and pores inside. The particle AG has an ill-defined amorphous shape. Fig. 14B As shown, these particles include a plurality of sub-particles, two of which are labeled SP1 and SP2. The average maximum dimension of the sub-particles is about 50 to 100 nm.

[0221] refer to Fig. 9 An example of a method according to an embodiment of the ninth aspect of the present invention is described. The method is generally indicated by reference numeral 500 and is a method for preparing a method containing desired alpha lead oxide, beta lead oxide, Pb 2 O 3 , red lead and metallic lead. The method 500 includes 501 determining the composition needs alpha lead oxide, beta lead oxide, Pb 2 O 3 , red lead and metallic lead. In this particular example, we 501 determine that a composition containing red lead is needed. Method 500 includes: based on the determination, 502 select one or more reaction parameters from one or more heating temperatures, one or more heating durations, and one or more gas components. As described above, to prepare a composition containing red lead, we heat lead citrate in a mixture of air and carbon dioxide, and then heat the resulting composition in a stream of air at 400°C. Therefore, we 502 select a first gas composition including carbon dioxide and air, in which lead citrate is heated. We also select a second gas composition including air for subsequent heating at 400°C, the second gas composition including air. Then we heat lead citrate in a mixture of air and carbon dioxide at a temperature of 350°C for two hours, and then heat the resulting composition in air at a temperature of 400°C for one hour, thereby obtaining a composition containing red lead.

[0222] Reference now Fig.10 An example method of manufacturing a battery panel according to another embodiment of the present invention is described. The method of forming a lead-acid battery panel is generally indicated by reference numeral 600. The method 600 includes combining 601 the composition of the second, fourth, sixth and / or eighth aspects of the present invention with one or more battery panel additives and an acid to form a paste. Sulfuric acid is generally used as the acid to convert the lead oxide in the composition into PbSO 4Suitable battery plate additives include those listed above, including metal compounds, insoluble carbon, barium sulfate, and fibers, such as lignin-based fibers. The paste may then be applied 602 to a grid (typically a lead alloy grid) and cured 603 to form a lead-acid battery plate.

[0223] Fig.11 1 is a simplified exploded perspective view of a battery according to an embodiment of the present invention. The battery is generally indicated by reference numeral 1000 and includes a plurality of battery panels, of which only one battery panel 1001 is labeled. Battery panel 1001 is arranged as described above with respect to Fig.10 The battery panel manufactured by the method described above. The battery panel 1001 is located in a plastic housing 1003. Sulfuric acid is located in the housing 1003 and in contact with the battery panel 1001.

[0224] Many of the above methods involve an oxidation process, sometimes followed by a thermal decomposition process, depending on the method. Oxidation processes are generally exothermic, while thermal decomposition processes are generally endothermic. The net energy required is the difference between the heat absorbed by the endothermic process and the heat generated by the exothermic process, so the energy required for the process may be relatively low or neutral, but sometimes, the process can gain net energy.

[0225] Although the present invention has been described and illustrated with reference to specific embodiments, those skilled in the art will appreciate that the present invention may have many different variations not specifically described herein. By way of example only, some possible variations will now be described.

[0226] In some of the above examples, nitrogen is used as the inert gas. Those skilled in the art will recognize that other inert gases may be used, such as any noble gas.

[0227] The above example illustrates how to use air to provide molecular oxygen as an oxidant. Those skilled in the art will recognize that oxidants other than molecular oxygen can be used. In addition, it is not necessary to provide molecular oxygen in air.

[0228] The inventors have demonstrated that the compositions according to the invention can be made using the methods described herein. A person skilled in the art will recognize that other methods can be used to obtain the compositions according to the invention.

[0229] The above examples demonstrate that lead citrate can be used as a starting material. Those skilled in the art will recognize that other organic lead salts can also be used. In particular, those skilled in the art will recognize that other lead carboxylates can also be used.

[0230] The above examples use lead citrate having particle sizes and shapes. One skilled in the art will recognize that lead citrate having different shapes and sizes may be used.

[0231] The method exemplified above uses a rotary furnace. Those skilled in the art will recognize that other furnaces or reaction vessels may be used.

[0232] When reference is made to known, obvious or foreseeable equivalents or elements in the foregoing description, such equivalents are incorporated herein as if set forth separately. The true scope of the invention should be determined with reference to the claims, which should be interpreted as covering any such equivalents. The reader should also understand that the entirety or features of the invention described as preferred, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. In addition, it should be understood that such optional entireties or features, although they may have benefits in some embodiments of the invention, may not be desirable in other embodiments and therefore may not exist.

Claims

1. A composition comprising α-lead oxide, β-lead oxide, metallic lead, Pb 2 O 3 and Pb 3 O 4 The composition comprises particles comprising sub-particles in the form of protrusions, wherein the average maximum dimension of the sub-particles is from 10 to 300 nm.

2. The composition of claim 1, wherein the composition contains one or more of alpha, beta oxide and beta lead oxide.

3. The composition according to claim 1 or 2, comprising metallic lead.

4. A composition according to claim 3, comprising at least 5 wt% metallic lead.

5. A composition according to claim 3 or 4, containing not more than 40 wt% of metallic lead.

6. A composition according to any one of the preceding claims, wherein the composition comprises rod-shaped particles. The composition according to claim 6 , wherein the maximum dimension of the rod-shaped particles is from 0.2 μm to 20 μm.

8. A composition according to claim 6 or 7, wherein at least 50% by number of the particles in the composition are rod-shaped particles.

9. The composition according to any one of claims 6 to 8, wherein at least 50% by number of the rod-shaped particles have a maximum dimension of 0.2 μm to 20 μm.

10. A composition according to any one of claims 6 to 9, wherein at least 50% by number of the rod-shaped particles have an aspect ratio of at least 1.5:1, and optionally an aspect ratio of no more than 20:

1.

11. A composition according to any one of the preceding claims, wherein the subparticles have an average maximum dimension of at least 20 nm.

12. A composition according to any one of the preceding claims, wherein the average maximum dimension of the subparticles does not exceed 200 nm.

13. A composition according to any one of the preceding claims, wherein the subparticles have an average maximum dimension of 50 to 150 nm.

14. A composition according to any one of the preceding claims, wherein the composition contains at least 95 wt% of alpha lead oxide, beta lead oxide, metallic lead, Pb 2 O 3 and one or more of red lead.

15. The composition according to claim 14, wherein the composition contains at least 98 wt% of alpha lead oxide, beta lead oxide, metallic lead, Pb 2 O 3 and one or more of red lead.

16. A composition according to any one of the preceding claims, wherein the composition has a BET surface area of ​​at least 1.0 m 2 / g.

17. The composition of claim 16, wherein the composition has a BET surface area of ​​at least 2.5 m 2 / g.

18. A composition according to any preceding claim comprising particles comprising a metallic lead rich and oxide poor core portion, the core portion optionally being spherical or sub-spherical, and an oxide rich outer portion.

19. A method for preparing a composition containing alpha lead (II) oxide, the method comprising: include: Conversion of organic lead salts into PbOPbCO 3 , the organic lead salt is optionally lead citrate; as well as The PbOPbCO is heated in a substantially inert atmosphere. 3 .

20. The process according to claim 19, wherein the organic lead salt, which is optionally lead citrate, is converted into PbOPbCO 3 The invention comprises converting an organic lead salt, which is optionally lead citrate, into lead (II) oxide, and converting the lead (II) oxide into PbOPbCO 3 .

21. The method of claim 20, wherein converting an organic lead salt, such as lead citrate, to lead (II) oxide comprises heating the organic lead salt, optionally lead citrate, in the presence of an oxidizing agent; converting the lead (II) oxide to PbOPbCO 3 The method comprises heating the lead (II) oxide in the presence of carbon dioxide to form lead carbonate; and converting the lead carbonate into PbOPbCO 3 .

22. The method of claim 21, wherein the oxidant comprises molecular oxygen and the molar ratio of carbon dioxide to molecular oxygen is at least 15:

1.

23. A composition comprising alpha lead oxide, prepared or obtainable by a process as claimed in any one of claims 19 to 22.

24. A method of preparing a composition containing beta lead oxide, the method comprising heating an organic lead salt, optionally lead citrate, in a gas stream containing an oxidant.

25. The method of claim 24, comprising mixing a precursor gas containing an oxidant with a diluent gas to provide a gas containing an oxidant.

26. The method of claim 25, wherein a molar ratio of the diluent gas to the precursor gas is at least 1:10 and no greater than 3:

1.

27. A method according to any one of claims 24 to 26, wherein the oxidant is in the form of a gaseous oxidant, the oxidant-containing gas containing at least 5 wt% and no more than 14 wt% oxidant.

28. A composition comprising beta lead oxide, prepared or obtainable by a process as claimed in any one of claims 24 to 27.

29. A method for preparing a composition containing red lead, the method comprising: include: Conversion of organic lead salts into PbOPbCO 3 , the organic lead salt is optionally lead citrate; as well as PbOPbCO 3 Converted to red lead.

30. The process of claim 29, wherein the organic lead salt, optionally lead citrate, is converted into PbOPbCO 3 The invention relates to a method for converting an organic lead salt, optionally lead citrate, into lead (II) oxide, converting the lead (II) oxide into lead carbonate, and converting the lead carbonate into PbOPbCO 3 .

31. The method of claim 30, wherein converting an organic lead salt, optionally lead citrate, to lead (II) oxide comprises heating the organic lead salt, optionally lead citrate, in the presence of an oxidizing agent; and converting the lead (II) oxide to lead carbonate comprises heating the lead (II) oxide in the presence of carbon dioxide.

32. The method according to any one of claims 29 to 31, wherein PbOPbCO 3 The conversion into red lead involves converting PbOPbCO 3 Conversion into alpha lead oxide, and conversion of alpha lead oxide into red lead.

33. The method according to claim 32, wherein PbOPbCO 3 The conversion into alpha lead oxide comprises heating PbOPbCO at a temperature of at least 350°C in the presence of a gas stream containing an oxidant. 3 , optionally heated at a temperature of at least 375°C.

34. A composition containing red lead prepared or obtainable by the method of any one of claims 29 to 33.

35. A method for preparing a Pb 2 O 3 Composition of the method, the method include: Conversion of organic lead salts into PbOPbCO 3 , the organic lead salt is optionally lead citrate; as well as PbOPbCO 3 Converted to Pb 2 O 3 .

36. The process of claim 35, wherein the organic lead salt, optionally lead citrate, is converted into PbOPbCO 3 The method comprises converting an organic lead salt, optionally lead citrate, into lead (II) oxide, optionally converting the lead (II) oxide into lead carbonate and converting the lead carbonate into PbOPbCO 3 .

37. The method of claim 36, wherein converting an organic lead salt, optionally lead citrate, to lead (II) oxide comprises heating the organic lead salt, optionally lead citrate, in the presence of an oxidizing agent; and converting the lead (II) oxide to lead carbonate comprises heating the lead (II) oxide in the presence of carbon dioxide.

38. The method according to claim 35 or 36, wherein PbOPbCO 3 Converted to Pb 2 O 3 Including PbOPbCO 3 Conversion to alpha lead oxide, and conversion of alpha lead oxide to Pb 2 O 3 .

39. The method according to claim 38, wherein PbOPbCO 3 The conversion into alpha lead oxide comprises heating PbOPbCO at a temperature not exceeding 350°C in the presence of a gas stream containing an oxidant. 3 , optionally heated at a temperature not exceeding 325°C.

40. A kind of Pb 2 O 3 A composition prepared or obtainable by the method of any one of claims 35 to 39.

41. A method for preparing a product containing the required α-lead oxide, β-lead oxide, Pb 2 O 3 , red lead and metallic lead, wherein the method include: Determine what is needed in the composition: alpha lead oxide, beta lead oxide, Pb 2 O 3 , red lead and metallic lead; selecting one or more reaction parameters from one or more heating temperatures, one or more heating durations, and one or more gas compositions based on the determination; and Heating an organic lead salt, optionally lead citrate, according to one or more selected reaction parameters, thereby obtaining a product containing the desired alpha lead oxide, beta lead oxide, Pb 2 O 3 , red lead and metallic lead.

42. The method of any one of claims 20-22, 24-27, 29-33, 35-39 and 41, wherein the particles of the organic lead salt, optionally lead citrate, are rod-shaped particles and have an average maximum dimension of at least 0.5 μm and not more than 20 μm.

43. A method of forming a lead acid battery plate comprising mixing the composition of any of claims 1-18, 23, 28, 34 and 40 with one or more battery plate additives and an acid to form a paste.

44. A lead acid battery plate produced or producible by the method of claim 43.

45. A lead acid battery comprising one or more battery plates according to claim 44.

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