Cadmium/silver oxide batteries

The silver-cadmium (cadmium/silver oxide) battery has significantly longer cycle life and better low-temperature performance than the silver-zinc battery but is inferior in these characteristics compared with the nickel-cadmium battery. Its energy density, too, is between that of the nickel-cadmium and the silver-zinc batteries. The battery is also very expensive, using two of the more costly electrode materials. As a result, the silver-cadmium battery was never developed commercially but is used in special applications, such as nonmagnetic batteries and space applications. Other silver battery systems, such as silver-hydrogen and silver-metal hydride couples, have been the subject of development activity but have not reached commercial viability. 

Discharge Performance for Cadmium/Silver Oxide Batteries... 

The performance characteristics of the cadmium/silver oxide battery are summarized in Figs. 33.12 and 33.13a and b, which can be used to determine the capacity, service life, and voltage levels under a variety of discharge conditions. 

Chizhikov, D. M., Cadmium, Pergamon Press, 1966 (mainly the technology of production). Fleischer, A., and J. J. Lander, Zinc-Silver Oxide Batteries, Wiley, 1971. 

The electrodes in a silver oxide battery are silver oxide (Ag20) and zinc, (a) Which electrode acts as the anode (b) Which battery do you think has an energy density most similar to the silver oxide battery a Li-ion battery, a nickel-cadmium battery, or a lead-acid battery [Section 20.7]... 

Union Carbide Corporation Consumer Products, 270 Park Avenue. New York 10017, New York Secondary batteries, nickel-cadmium, silver-oxide, sodium-nickel chloride secondary. 

Fig. 1. Schematic representation of a battery system also known as an electrochemical transducer where the anode, also known as electron state 1, may be comprised of lithium, magnesium, zinc, cadmium, lead, or hydrogen, and the cathode, or electron state 11, depending on the composition of the anode, may be lead dioxide, manganese dioxide, nickel oxide, iron disulfide, oxygen, silver oxide, or iodine.

Silver [7440-22-4] Ag, as an active material in electrodes was first used by Volta, but the first intensive study using silver as a storage battery electrode was reported in 1889 (5) using silver oxide—iron and silver oxide—copper combinations. Work on silver oxide—cadmium followed. In the 1940s, the use of a semipermeable membrane combined with limited electrolyte was introduced by Andrir in the silver oxide—2inc storage battery. 

In acidic electrolytes only lead, because it forms passive layers on the active surfaces, has proven sufficiently chemically stable to produce durable storage batteries. In contrast, in alkaline medium there are several substances basically suitable as electrode materials nickel hydroxide, silver oxide, and manganese dioxide as positive active materials may be combined with zinc, cadmium, iron, or metal hydrides. In each case potassium hydroxide is the electrolyte, at a concentration — depending on battery systems and application — in the range of 1.15 - 1,45 gem"3. Several elec-... 

For alkaline storage batteries requirements are often demanded exceeding by far those for lead storage batteries. The reason is that the suitable materials for the positive electrode are very expensive (silver oxide, nickel hydroxide) and thus the use of these storage batteries is only justified where requirements as to weight, number of cycles, or temperature range prohibit other solutions. Besides a few standardized versions — mainly for nickel-cadmium batteries — this has led to the existence of a large diversity of constructions for special applications [4-6, 108, 109],... 

There are two major types of household batteries (a) Primary batteries are those that cannot be reused. They include alkaline/manganese, carbon-zinc, mercuric oxide, zinc-air, silver oxide, and other types of button batteries, (b) Secondary batteries are those that can be reused secondary batteries (rechargeable) include lead-acid, nickel-cadmium, and potentially nickel-hydrogen. 

Subcategory A encompasses the manufacture of all batteries in which cadmium is the reactive anode material. Cadmium anode batteries currently manufactured are based on nickel-cadmium, silver-cadmium, and mercury-cadmium couples (Table 32.1). The manufacture of cadmium anode batteries uses various raw materials, which comprises cadmium or cadmium salts (mainly nitrates and oxides) to produce cell cathodes nickel powder and either nickel or nickel-plated steel screen to make the electrode support structures nylon and polypropylene, for use in manufacturing the cell separators and either sodium or potassium hydroxide, for use as process chemicals and as the cell electrolyte. Cobalt salts may be added to some electrodes. Batteries of this subcategory are predominantly rechargeable and find application in calculators, cell phones, laptops, and other portable electronic devices, in addition to a variety of industrial applications.1-4 A typical example is the nickel-cadmium battery described below. 

It must be emphasized that the most appropriate charging regime is very dependent on the cell system under consideration. Some are tolerant to a considerable amount of overcharging (e.g. nickel-cadmium batteries), while for others, such as zinc-silver oxide and most lithium secondary cells, overcharging can result in permanent damage to the cell. Sealed battery systems require special care float charging should not be used and trickle charge rates should be strictly limited to the manufacturer s recommended values, since otherwise excessive cell temperatures or thermal runaway can result. 

Historically lead-acid, silver oxide and industrial nickel cadmium batteries were collected by entrepreneurs and recycled at the end of their lives due to the economic value in the materials they contained. 

Uses Cadmium plating reagent electrodes for storage batteries cadmium salts oxidation/hydrogenation catalyst ceramic glazes nematicide silver alloy ingred. raw material for glass, phosphors, semiconductors vulcanization accelerator, activator... 

During the last several years, the market for mercuric oxide batteries has almost completely evaporated, due mainly to environmental problems associated with mercury and cadmium and few are manufactured. They have been removed from the International Electrotechnical Commission (lEC) and the American National Standards Institute (ANSI) standards. In applications, they have been replaced by alkaline-manganese dioxide, zinc/air, silver oxide and lithium batteries. 

Nickel-Zinc Batteries. The nickel-zinc (zinc/nickel oxide) battery has characteristics midway between those of the nickel-cadmium and the silver-zinc battery systems. Its energy density is about twice that of the nickel-cadmium battery, but the cycle life previously has been limited due to the tendency of the zinc electrode toward shape change which reduces capacity and dendrite formations, which cause internal short-circuiting. 

Other cells, based on zinc anodes or on mercuric oxide cathodes are known. Among them are the silver-zinc battery, zinc-copper oxide battery, mercury-cadmium battery etc. 

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