Nickel-cadmium Accumulators
Nickel-cadmium batteries are a secondary chemical source of current; in the role of cathode, nickel hydrate plus graphite powder, electrolyte-potassium hydroxide plus lithium hydroxide, anode-cadmium oxide hydrate acts here. The operating period can vary from 200 to 1000 charge / discharge cycles, it all depends on the design features, the purity of the material used to produce the batteries. Today there are nickel-cadmium batteries, which can work up to 20 years.
A bit of history
Nickel-cadmium batteries (accumulators) were invented by the Swedish scientist Waldemar Junger, back in 1899, in such a battery the positive electrode was made of nickel, and the negative one from cadmium. A couple of years later Edison proposed an alternative design where cadmium was replaced by iron. But the cost of both batteries was high enough, so the battery did not go into mass production. Then, Schlecht and Ackerman invented in 1932 a compressed anode, which was more durable, withstanding considerable current loads. A well-known nickel-cadmium battery at the moment appeared thanks to Newman (1947), after he invented a fully sealed element.
Use of a nickel-cadmium battery
Small-sized NCBs are used in various equipment and equipment as a replacement for conventional galvanic cells; this is especially true when the technique requires the supply of a large current, while the power is more stable.
They are used in:
- Electric vehicles (traction);
- Trams;
- Trolley buses (control circuit power supply);
- River, sea vessels;
- Aviation (on-board batteries in aircraft, helicopters);
- Power supply in self-contained screwdrivers, screwdrivers, drills;
- Diving lights;
- Military equipment, aviation;
- Portable communication.
Widely used nickel-cadmium batteries in the form of disks. This kind of their type was widely used, like a battery in the memory supply, depending on the power consumption in the production of personal computers of the first generations. They were uninstalled on motherboards, later they were replaced with lithium batteries. In addition, disk NCA are used in flash units, in cameras themselves; calculators and flashlights, radios and hearing aids also cannot do without this element.
Nickel-cadmium batteries must be completely discharged, since when using and completely discharging the internal plates of the element are covered with crystals that reduce the storage capacity; this effect is called the “memory effect”.
Also, the fact that the NCA has a high price for their disposal influences the use decrease – they are disposed of in special furnaces, at extremely high temperatures. The furnace must be equipped with a specialized filter that detects volatile toxic elements that poison the air.
