摘要:
Embodiments are described in terms of selective methods of sealing separators and jellyroll electrode assemblies and cells made using such methods. More particularly, methods of selectively heat sealing separators to encapsulate one of two electrodes for nickel-zinc rechargeable cells having jellyroll assemblies are described. Selective heat sealing may be applied to both ends of a jellyroll electrode assembly in order to selectively seal one of two electrodes on each end of the jellyroll.
摘要:
A rechargeable pencil battery has a hollow cylindrical positive electrode including nickel hydroxide; a gelled negative electrode comprising at least one of zinc and a zinc compound; a separator interposed between the hollow cylindrical positive electrode and the gelled negative electrode; and a negative electrode current collector inserted into the gelled negative electrode. Rechargeable batteries of the invention are capable of between about 50 and 1000 cycles from a fully charge state to a fully discharged state at a discharge rates of about 0.5 C or greater, in some embodiments about 1 C or greater. Batteries of the invention have a ratio of length to diameter of between about 1.5:1 and about 20:1, and therefore can be longer than typical commercially available batteries but also include batteries of commercial sizes e.g. AAAA, AAA, AA, C, D, sub-C and the like.
摘要:
An improved Ni—Zn cell with a negative electrode substrate plated with tin or tin and zinc during manufacturing has a reduced gassing rate. The copper or brass substrate is electrolytic cleaned, activated, electroplated with a matte surface to a defined thickness range, pasted with zinc oxide electrochemically active material, and baked. The defined plating thickness range of 40-80 μIn maximizes formation of an intermetallic compound Cu3Sn that helps to suppress the copper diffusion from under plating layer to the surface and eliminates formation of an intermetallic compound Cu6Sn5 during baking to provide adequate corrosion resistance during battery operation.
摘要:
The conductivity of a zinc negative electrode is enhanced through use of surfactant-coated carbon fibers. Carbon fibers, along with other active materials such as bismuth oxide, zinc etc., form an electronically conductive matrix in zinc negative electrodes. Zinc negative electrodes as described herein are particularly useful in nickel zinc secondary batteries.
摘要:
Active material for a negative electrode of a rechargeable zinc alkaline electrochemical cell is made with zinc metal particles coated with tin and/or lead. The zinc particles may be coated by adding lead and tin salts to a slurry containing zinc particles, a thickening agent and water. The remaining zinc electrode constituents such as zinc oxide (ZnO), bismuth oxide (Bi2O3), a dispersing agent, and a binding agent such as Teflon are then added. The resulting slurry/paste has a stable viscosity and is easy to work with during manufacture of the zinc electrode. Further, the zinc electrode is much less prone to gassing when cobalt is present in the electrolyte. Cells manufactured from electrodes produced in accordance with this invention exhibit much less hydrogen gassing, by as much as 60-80%, than conventional cells. The cycle life and shelf life of the cells is also enhanced, as the zinc conductive matrix remains intact and shelf discharge is reduced.
摘要翻译:可充电锌碱性电化学电池的负极的活性材料由涂覆有锡和/或铅的锌金属颗粒制成。 可以通过向含有锌颗粒,增稠剂和水的浆料中加入铅和锡盐来涂覆锌颗粒。 然后加入剩余的锌电极成分如氧化锌(ZnO),氧化铋(Bi 2 O 3),分散剂和粘结剂如特氟纶。 所得到的浆料/糊料具有稳定的粘度,并且在锌电极的制造过程中易于加工。 此外,当电解质中存在钴时,锌电极容易发生气体渗透。 从根据本发明生产的电极制造的电池比常规电池表现出少得多的氢气,多达60-80%。 电池的循环寿命和保质期也得到提高,因为锌导电基体保持完整,降低了放电。
摘要:
Methods of manufacturing a rechargeable power cell are described. Methods include providing a slurry or paste of negative electrode materials having low toxicity and including dispersants to prevent the agglomeration of particles that may adversely affect the performance of power cells. The methods utilize semi-permeable sheets to separate the electrodes and minimize formation of dendrites; and further provide electrode specific electrolyte to achieve efficient electrochemistry and to further discourage dendritic growth in the cell. The negative electrode materials may be comprised of zinc and zinc compounds. Zinc and zinc compounds are notably less toxic than the cadmium used in NiCad batteries. The described methods may utilize some production techniques employed in existing NiCad production lines. Thus, the methods described will find particular use in an already well-defined and mature manufacturing base.
摘要:
A zinc electrode for use in alkaline batteries comprises a mixture of 0.425 to 1.55 volume parts of zinc oxide with a volume part of a metallic oxide chosen from the group consisting of: calcium oxide, barium oxide, and mixtures thereof, together with hydroxy-ethyl cellulose, an oxide dispersant chosen from the group consisting of: soap derivatives, anionic polyelectrolytes, anionic surfactants, and mixtures thereof, and a binder. The electrode is prepared by mixing zinc oxide with the chosen metallic oxide in an aqueous medium such as water or potassium hydroxide, stirring overnight, filtering and drying the mixture, optionally adding a further small amount of zinc oxide, optionally adding other metallic oxides, and adding hydroxy-ethyl cellulose, an oxide dispersant, and a binder. The aqueous paste os slurry thus formed is placed on a conductive substrate, drawn through a sizing gap, cut and dried, to form low cost pasted zinc oxide electrodes.
摘要:
A zinc electrode composition is provided for use in low toxicity, high energy density cells having alkaline electrolytes. The zinc electrode comprises zinc oxide, a binder, and from 0.1% up to 10% of a fluoride of an element chosen from the group consisting of silver, gallium, indium, tin, tellurium, lead, bismuth, and combinations thereof. The invention also provides an electrochemical cell having an electrode as noted above. The inventive cell further comprises an electrolyte which contains a mixture of sodium, potassium, and lithium hydroxides, together with boric acid. The excess alkali hydroxide is present in the range of 2.7 to 5M, and the concentration of boric acid is between 0.6 and 1.3 moles per litre.
摘要:
A zinc electrode is provided for use in electrochemical cells having an alkaline electrolyte and high cycle life. The zinc electrode comprises a mixture of zinc oxide together with an inorganic fibre which contains silica and alumina. Preferably, the composition of the inorganic fibre is in the range of 80% to 99% alumina, and 1% to 20% silica. Typically, the zinc electrode will further comprise an inorganic fibre additive in the range of 2% to 15% by weight of the zinc oxide electrode. Also, the zinc electrode will typically further include 2% up to 10% of bismuth oxide.
摘要:
A control system is designed or configured to control the state of charge of a battery or battery pack in a system containing a separate power source, which is separate from the battery or battery pack. In operation, the battery or battery pack is called upon to intermittently provide power for certain functions. The separate power source may be, for example, an AC electrical power source for a UPS or an engine of a vehicle such as a micro hybrid vehicle. The battery may be a nickel zinc aqueous battery. The control system may be designed or configured to implement one or more of the following functions: monitoring the state of charge of the battery or battery pack; directing rapid recharge of the battery or battery pack from the separate power source when the battery or battery pack is not performing its functions; and directing charge to fully charged level or a float charge level, which is different from the fully charged level, in response to operating conditions.