Sealed nickel-cadmium secondary batteries

Then, A. B. Lange and others found how a cadmium electrode consumes the oxygen from a positive electrode during overcharging in 1938. Then, G. Neumann and others established the present sealing principle and basic structure of a sealed-type nickel-cadmium secondary battery in 1948. Then, the sealed-type nickel-cadmium secondary battery has come to rapidly spread mainly in the consumer electronic equipment market. 

In Japan, the Furukawa Battery Co., Ltd. industrialized a sintered-type vented nickel-cadmium battery for airplane starting in 1955. The Furukawa Battery Co., Ltd. started mass production of the vented-type nickel-cadmium secondary battery and a sealed nickel-cadmium secondary battery for industrial use in 1962 and developed the same to the fields, such as aircrafts. 

On the other hand, Sanyo Electric Co., Ltd. started mass production of a consumer sealed type nickel-cadmium secondary battery. Then, other companies produced a consumer sealed-type nickel-cadmium secondary battery commercially one after another. Then, the batteries have been used as the main power supply of portable electronic devices such as cordless power tools and toys, video cameras, and notebook PCs in 1980s, and the production amount has enlarged drastically. 

Primary batteries, zinc-alkaline manganese dioxide, mercury-zinc, carbon-zinc Leclanche, magnesium types, silver oxide-zinc, zinc chloride Leclanche, zinc-air secondary batteries, alkaline, nickel-iron, nickel-cadmium, silver-zinc, sealed lead-acid, zinc-air, nickel-metal hydride secondary, lithium-manganese dioxide, lithium-silver chromate, lithium-lead bismuthate. 

Nickel-cadmium and nickel-iron are prime examples of rechargeable (secondary) batteries, invented in 1901 by Waldemar Jungner and Edison, respectively. In the 1920s and 1930s, such batteries powered radios prior to rural clectrificadnn. The sealed nickel-cadmium battery is now the most widely used battery in consumer products. 

The manufacture of secondary batteries based on aqueous electrolytes forms a major part of the world electrochemical industry. Of this sector, the lead-acid system (and in particular SLI power sources), as described in the last chapter, is by far the most important component, but secondary alkaline cells form a significant and distinct commercial market. They are more expensive, but are particularly suited for consumer products which have relatively low capacity requirements. They are also used where good low temperature characteristics, robustness and low maintenance are important, such as in aircraft applications. Until recently the secondary alkaline industry has been dominated by the cadmium-nickel oxide ( nickel-cadmium ) cell, but two new systems are making major inroads, and may eventually displace the cadmium-nickel oxide cell - at least in the sealed cell market. These are the so-called nickel-metal hydride cell and the rechargeable zinc-manganese dioxide cell. There are also a group of important but more specialized alkaline cell systems which are in use or are under further development for traction, submarine and other applications. 

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. 

Hydrogen evolution can also be prevented, and thus the unwanted secondary reactions hydrogen evolution and grid corrosion that disturb the internal oxygen cycle in lead-acid batteries, as shown in Fig. 1.25, are not present in nickel/cadmium batteries, which therefore can be hermetically sealed so that neither vapor or gas escapes from the battery. This is the reason for the market success of these batteries in the field of portable applications. 

In battery systems based on aqueous electrolyte, water decomposition, which occurs above a cell voltage of 1.23 V, is such an unavoidable secondary reaction. But under certain conditions the resulting water loss can be avoided, and the system is used as a sealed one, as achieved with sealed nickel/cadmium, nickel/hydrogen, and nickel/metal hydride batteries. In lead-acid batteries corrosion is an additional unwanted secondary reaction with the consequence that lead-acid batteries cannot be made virtually sealed, but must have a valve, and a certain water loss cannot be prevented. 

Eveready sealed secondary nickel-cadmium cells and batteries are now widely used as a rechargeable power source in many different types of portable or cordless ele trical appliance. Charging at the safe recommended C/10 ratd has proved satisfactory for recharging the cells or batteries used in many of these appliances, such as toothbrushes, shavers, etc., where relatively long rest periods between uses are possible. However, there is now a demand for the use of sealed nickel-cadmium cells and batteries in other applianees, such as chain saws, electronic flashes, portable drills and professional hair elippers, where the rest periods between uses of the applianees are mueh shorter eonsequently shorter reeharging times, from about 3h to about 1 h, that is, C/3 to C/1 rates, are required. 

Primary batteries, carbon-zinc Leclanchd, magnesium types, lithium types, silver oxide-zinc secondary batteries, nickel-cadmium, silver-zinc, silver-cadmium, sealed lead-acid. 

Yuasa Battery Co. Ltd, 6-6 Josai-cho, Takatsukishi, Osaka-fii 569 also International Division, 12-112 Chome, Higashi-Shinbashi Minako-ku, Tokyo 105 Primary batteries, carbon-zinc Leclanchd, silver oxide-zinc secondary batteries, nickel-iron, nickel-cadmium, silver-zinc, silver-cadmium, sealed lead-acid. Sodium-sulphur, lithium-manganese dioxide. 

Secondary batteries, nickel-cadmium, sealed lead-acid, sodium-sulphur. 

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