摘要:
This invention teaches rechargeable manganese dioxide cells having alkaline electrolytes, zinc negative electrodes and manganese dioxide positive electrodes. In keeping with the present invention, the positive electrode is essentially unconstrained--that is, no cage is used in the cell to confine the positive electrode. During discharge of a rechargeable alkaline cell, the positive electrode may be inclined to swell, and during the charge cycle it may be inclined to contract or reduce its dimensions. However, the positive electrode is dimensioned so as to substantially fill the entire space allotted for it within the cell, while allowing for a slight accommodation for height-wise or longitudinal expansion or growth in bobbin cells. The positive electrode may include additives such as carbon or graphite to increase its electrical conductivity; hydrophobic agents such as PTFE, polyethylene or polypropylene to enhance the hydrogen permeability of the positive electrode and thereby lead to increased hydrogen recombination rates; and similar hydrophobic agents as well as hydrophillic additives to serve as lubricants and to reduce tool wear during manufacturing processes. Also, the discharge capacity of the negative electrode may be established so as to be in the range of from about 60% to about 120% of the theoretical one electron discharge capacity of the positive MnO.sub.2 electrode.
摘要:
This invention relates to rechargeable manganese dioxide cells (usually alkaline cells with zinc anodes or cells having non-aqueous electrolyte and lithium anodes), and particularly to the cathodes therefore. In keeping with the present invention, the cathodes are essentially unconstrained--that is, no cage is used in the cell between the cathodes and the anodes. The cathode is restricted from significantly changing its dimensions during discharge of the cell, when it is inclined to swell--as opposed to the tendency of the cathode to contract during a charge cycle. The cathode substantially fills the entire space allotted for it within the cell, with a light accommodation for height-wise or longitudinal expansion or growth of the cathode of bobbin-type cells, or crosswise expansion or growth of button-type cells. There may be additives in the cathode mix, including particularly conductive fibres of graphite or other conductive materials; and other materials may also be added to the cathode mix, including metallic additives. Methods of manufacture are also provided by the present invention, including compaction and recompaction of the cathode pellet, and a range of compaction pressures is suggested. Cells in keeping with the present invention are capable of exhibiting high current drain rates, and long cycle life.
摘要:
This invention relates to rechargeable manganese dioxide cells (usually alkaline cells with zinc anodes or cells having non-aqueous electrolyte and lithium anodes), and particularly to the cathodes therefore. In keeping with the present invention, the cathodes are essentially unconstrained--that is, no cage is used in the cell between the cathodes and the anodes. The cathode is restricted from significantly changing its dimensions during discharge of the cell, when it is inclined to swell--as opposed to the tendency of the cathode to contract during a charge cycle. The cathode substantially fills the entire space allotted for it within the cell, with a light accommodation for height-wise or longitudinal expansion or growth of the cathode of bobbin-type cells, or cross-wise expansion or growth of button-type cells. There may be additives in the cathode mix, including particularly conductive fibres of graphite or other conductive materials; and other materials may also be added to the cathode mix, including metallic additives. Methods of manufacture are also provided by the present invention, including compaction and recompaction of the cathode pellet, and a range of compaction pressures is suggested. Cells in keeping with the present invention are capable of exhibiting high current drain rates, and long cycle life.
摘要:
This invention relates to rechargeable manganese dioxide cells (usually alkaline cells with zinc anodes or cells having non-aqueous electrolyte and lithium anodes), and particularly to the cathodes therefor. In keeping with the present invention, the cathodes are essentially unconstrained--that is, no cage is used in the cell between the cathodes and the anodes. The cathode is restricted from significantly changing its dimensions during discharge of the cell, when it is inclined to swell--as opposed to the tendency of the cathode to contract during a charge cycle. The cathode substantially fills the entire space alloted for it within the cell, with a slight accommodation for height-wise or longitudinal expansion or growth of the cathode of bobbin-type cells, or cross-wise expansion or growth of button-type cells. There may be additives in the cathode mix, including particularly conductive fibres of graphite or other conductive materials; and other materials may also be added to the cathode mix, including metallic additives. Methods of manufacture are also provided by the present invention, including compaction and recompaction of the cathode pellet, and a range of compaction pressure is suggested. Cells in keeping with the present invention are capable of exhibiting high current drain rates, and long cycle life.
摘要:
This invention relates to rechargeable manganese dioxide cells (usually alkaline cells with zinc anodes or cells having non-aqueous electrolyte and lithium anodes), and particularly to the cathodes therefor. In keeping with the present invention, the cathodes are essentially unconstrained--that is, no cage is used in the cell between the cathodes and the anodes. The cathode is restricted from significantly changing its dimensions during discharge of the cell, when it is inclined to swell--as opposed to the tendency of the cathode to contract during a charge cycle. The cathode substantially fills the entire space alloted for it within the cell, with a slight accommodation for height-wise or longitudinal expansion or growth of the cathode of bobbin-type cells, or cross-wise expansion or growth of button-type cells. There may be additives in the cathode mix, including particularly conductive fibres of graphite or other conductive materials; and other materials may also be added to the cathode mix, including metallic additives. Methods of manufacture are also provided by the present invention, including compaction and recompaction of the cathode pellet, and a range of compaction pressures is suggested. Cells in keeping with the present invention are capable of exhibiting high current drain rates, and long cycle life.
摘要:
Metal-clad polymer articles containing structural fine-grained and/or amorphous metallic coatings/layers optionally containing solid particulates dispersed therein, are disclosed. The fine-grained and/or amorphous metallic coatings are particularly suited for strong and lightweight articles, precision molds, sporting goods, automotive parts and components exposed to thermal cycling although the coefficient of linear thermal expansion (CLTE) of the metallic layer and the substrate are mismatched. The interface between the metallic layer and the polymer is suitably pretreated to withstand thermal cycling without failure.
摘要:
Anode applicators include consumable anodes, that can be operated in a non-stationary mode and are insensitive to orientation, are used in selective plating/brush electrodeposition of coatings or free-standing components. The flow-through dimensionally-stable, consumable anodes employed are perforated/porous to provide relatively unimpeded electrolyte flow and operate at low enough electrochemical potentials to provide for anodic metal/alloy dissolution avoiding undesired anodic reactions. The consumable anodes include consumable anode material(s) in high surface area to reduce the local anodic current density. During electroplating, sufficient electrolyte is pumped through the consumable anodes at sufficient flow rates to minimize concentration gradient and/or avoid the generation of chlorine and/or oxygen gas and/or undesired reaction such as the anodic oxidation of P-bearing ions in the electrolyte. The active consumable anode material(s) can have a microstructure which is fine-grained and/or amorphous to ensure a uniform anodic dissolution.
摘要:
Composite current collectors containing coatings of metals, alloys or compounds, selected from the group of Zn, Cd, Hg, Ga, In, Tl, Sn, Pb, As, Sb, Bi and Se on non-metallic, non-conductive or poorly-conductive substrates are disclosed. The composite current collectors can be used in electrochemical cells particularly sealed cells requiring a long storage life. Selected metals, metal alloys or metal compounds are applied to polymer or ceramic substrates by vacuum deposition techniques, extrusion, conductive paints (dispersed as particles in a suitable paint), electroless deposition, cementation; or after suitable metallization by galvanic means (electrodeposition or electrophoresis). Metal compound coatings are reduced to their respective metals by chemical or galvanic means. The current collectors described are particular suitable for use in sealed primary or rechargeable galvanic cells containing mercury-fee and lead-free alkaline zinc electrodes.
摘要:
Composite current collectors containing coatings of metals, alloys or compounds, selected from the group of Zn, Cd, Hg, Ga, In, Tl, Sn, Pb, As, Sb, Bi and Se on non-metallic, non-conductive or poorly-conductive substrates are disclosed. The composite current collectors can be used in electrochemical cells particularly sealed cells requiring a long storage life. Selected metals, metal alloys or metal compounds are applied to polymer or ceramic substrates by vacuum deposition techniques, extrusion, conductive paints (dispersed as particles in a suitable paint), electroless deposition, cementation; or after suitable metallization by galvanic means (electrodeposition or electrophoresis). Metal compound coatings are reduced to their respective metals by chemical or galvanic means. The current collectors described are particular suitable for use in sealed primary or rechargeable galvanic cells containing mercury-free and lead-free alkaline zinc electrodes.
摘要:
Free standing articles or articles at least partially coated with substantially porosity free, fine-grained and/or amorphous Co-bearing metallic materials optionally containing solid particulates dispersed therein, are disclosed. The electrodeposited metallic layers and/or patches comprising Co provide, enhance or restore strength, wear and/or lubricity of substrates without reducing the fatigue performance. The fine-grained and/or amorphous metallic coatings comprising Co are particularly suited for articles exposed to thermal cycling, fatigue and other stresses and/or in applications requiring anti-microbial properties.