Batteries disposable

Environmental hazards of batteries can be briefly summarized as follows. A battery is an electrochemical device with the ability to convert chemical energy to electrical energy to provide power to electronic devices. Batteries may contain lead, cadmium, mercury, copper, zinc, lead, manganese, nickel, and lithium, which can be hazardous when incorrectly disposed. Batteries may produce the following potential problems or hazards (a) they pollute the lakes and streams as the metals... 

The electrolyte was a solution of ammonium chloride that bathed the electrodes. Like Plante s electrochemistry of the lead-acid battery, Leclanche s electrochemistry survives until now in the form of zinc-carbon dry cells and the use of gelled electrolyte.12 In their original wet form, the Leclanche electrochemistry was neither portable nor practicable to the extent that several modifications were needed to make it practicable. This was achieved by an innovation made by J. A. Thiebaut in 1881, who through encapsulating both zinc cathode and electrolyte in a sealed cup avoided the leakage of the liquid electrolyte. Modern plastics, however, have made Leclanche s chemistry not only usable but also invaluable in some applications. For example, Polaroid s Polar Pulse disposable batteries used in instant film packs use Leclanche chemistry, albeit in a plastic sandwich instead of soup bowls.1... 

A dry cell battery stops producing electricity when the reactants are used up. This type of battery is disposable after it has run down completely. A disposable battery is known as a primary battery. Some other batteries are rechargeable. A rechargeable battery is known as a secondary battery. The rest of this section will deal with primary batteries. You will learn about secondary batteries in section 11.3. 

In section 11.1, you learned about several primary (disposable) batteries that contain galvanic cells. One of the most common secondary (rechargeable) batteries is found in car engines. Most cars contain a lead-acid battery, shown in Figure 11.18. When you turn the ignition, a surge of electricity from the battery starts the motor. 

Are the chemical reactions that take place in a disposable battery exothermic or endothermic What evidence supports your answer Is the reaction going on in a rechargeable battery while it is recharging exothermic or endothermic ... 

Another type of disposable battery, the more expensive alkaline battery, shown in Figure 11.10, avoids many of the problems of dry-cell batteries by operating in a strongly alkaline paste. In the presence of hydroxide ions, the zinc oxidizes to insoluble zinc oxide ... 

The small mercury and lithium disposable batteries used for calculators and cameras are variations of the alkaline battery. In the mercury battery, mercuric oxide, HgO, is reduced rather than manganese dioxide. Manufacturers are phasing out these batteries because of the environmental hazard posed by mercury, which is poisonous. In the lithium battery, lithium metal is used as the source of electrons rather than zinc. Not only is lithium able to maintain a higher voltage than zinc, it is about 13 times less dense, which allows for a lighter battery. 

Disposable batteries have relatively short lives because electron-producing chemicals are consumed. The main feature of rechargeable batteries is the reversibility of the oxidation and reduction reactions. In your car s rechargeable lead storage battery, for example, electrical energy is produced as lead dioxide, lead, and sulfuric acid are consumed to form lead sulfate and water. The elemental lead is oxidized to Pb2+, and the lead in the lead dioxide is reduced from the Pb4+ state to the Pb2+ state. Combining the two half-reactions gives the complete oxidation-reduction reaction ... 

Another major technology area that can utflize conductive IJ ink is the display market. Inkjet can be applied for both flexible and rigid displays such as electroluminescent and electrophoretic displays (including e-paper), hquid crystal displays (LCD), plasma display panels (PDP) and touch screens some functionalities have already been printed by IJ technology in certain display apphcations, for example RGB color filters. Conductive IJ is also appropriate for use in thin film transistors (TFT), disposable batteries, radio-frequency identification (RFID) tags, and a range of chemical and electronic sensors. 

Since toxic materials from improperly disposed batteries and other sources may enter ecosystems that extend beyond national boundaries, the solution of the environmentalj)roblem requires international cooperation as well as technical cooperation. The efforts of the European Community of Nations (7,8) is a good example of what can be accomplished within an international framework, although much more needs to be done. 

All waste batteries are considered RCRA solid waste except those that are returned to the manufacturer for regeneration, reused as an ingredient without reclamation, reused as a substitute, or returned as raw material. The largest percentage of disposed batteries are part of household waste and therefore exempt from regulation. The remaining waste batteries must be determined by the... 

The only power sources feasible for all these portables are electrochemical batteries. Disposable batteries were the classical power source for flashlights, and still hold a very strong position (salt Leclanche later, alkaline dry cells of zinc-manganese dioxide type). Rechargeable batteries became ever more important first, nickel-cadmium, and more recently, nickel-hydride and lithium ion batteries. For convenient handling, a power source is usually placed somewhere inside the device, so it should respect certain limitations as to weight and volume. As a rule of thumb, a power source should not exceed 30-40% by mass and volume of the device powered by it. A similar upper limit 30-40% applies to the cost. 

One refers to a secondary battery, or rechargeable battery, when the system can function easily in two modes, namely that of electrolyser as well as power source (e.g., in the case of a mobile phone battery). One uses the term primary battery, non-rechargeable battery, or indeed disposable battery, when it Is impossible or difficult to recharge, i.e., to have itworking as an electrolyser. 

It is quite clear that we do not expect complete substitution of ordinary batteries by fuel cells in the portable field. Ordinary batteries will continue to maintain their leading market position as power sources for a large number of devices. Thus, disposable batteries are expected to maintain their importance for pocket flashlights and various medical devices, for example. Simple electronic devices such as portable radios, audio players, digital cameras, and so on, will continue to be powered by rechargeable nickel-cadmium and nickel-hydride batteries. Lithium-ion rechargeables are likely to continue in simpler mobile phones. Fuel cells will be attractive for more complex equipment, such as notebooks used for more than 2 hours at a time, for instance, where even lithium-ion batteries have insufficient energy density. 

Type BY-301 This 3000 A h, 1.25 V cell in a hard rab-ber case is designed for the operation of navigational signal aids, both visible and audible. The size and shape of the battery will permit it to replace lead storage cells now widely used in this application. Special disposable battery racks are currently available for buoys with 559 or 610 nun battery pockets. These racks are furnished completed with the proper number of BY Carbonaires and the entire unit is prewired at the factory. 

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