The Ultimate Guide to batteries
The Ultimate Guide to batteries
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The active material on the battery plates changes chemical composition on each charge and discharge cycle; active material may be lost due to physical changes of volume, further limiting the number of times the battery can be recharged.
Nickel-cadmium battery is also a type of rechargeable battery that uses nickel oxide hydroxide and the metal cadmium as electrodes. One of the main advantages of Ni-Cd batteries is that they can maintain voltage and hold a charge when not in use.
Batteries are represented in electrical schematics and diagrams by using a simple symbol. The symbol may differ depending on the type of battery used.
Battery life can be extended by storing the batteries at a low temperature, as in a refrigerator or freezer, which slows the side reactions. Such storage can extend the life of alkaline batteries by about 5%; rechargeable batteries can hold their charge much longer, depending upon type.
Charged batteries (rechargeable or disposable) lose charge by internal self-discharge over time although not discharged, due to the presence of generally irreversible side reactions that consume charge carriers without producing current. The rate of self-discharge depends upon battery chemistry and construction, typically from months to years for significant loss. When batteries are recharged, additional side reactions reduce capacity for subsequent discharges. After enough recharges, in essence all capacity is lost and the battery stops producing power.
A battery's capacity is the amount of electric charge it can deliver at a voltage that does not drop below the specified terminal voltage. The more electrode material contained in the cell the greater its capacity. A small cell has less capacity than a larger cell with the same chemistry, although they develop the same open-circuit voltage.[49] Capacity is usually stated in ampere-hours (A·h) (mAh for small batteries). The rated capacity of a battery is usually expressed as the product of 20 hours multiplied by the current that a new battery can consistently supply for 20 hours at 20 °C (68 °F), while remaining above a specified terminal voltage per cell.
It can be used for high- and low-drain devices but can wear out quickly in high-drain devices such as digital cameras. These batteries have a higher energy density and longer life, yet provide similar voltages as zinc-carbon акумулатори batteries.
It can be mounted in any position and does not require regular maintenance. It has a relief valve that is activated when the battery generates hydrogen gas.
Batteries work by converting chemical energy into electrical energy. This process is known as electrochemical oxidation-reduction or redox. When a battery is in use, the chemical reaction produces electrons, which flow through the battery to power the attached device.
, in strict usage, designates an assembly of two or more galvanic cells capable of such energy conversion, it is commonly applied to a single cell of this kind.
Leak-damaged alkaline battery Many battery chemicals are corrosive, poisonous or both. If leakage occurs, either spontaneously or through accident, the chemicals released may be dangerous. For example, disposable batteries often use a zinc "can" both as a reactant and as the container to hold the other reagents.
They have a long service life and are found in small portable devices such as watches and pocket calculators. It is made of stainless steel that forms the cell’s lower body and positive terminal and a metallic top cap forms the negative terminal.
Nevertheless, the negative electrodes use a hydrogen-absorbing alloy instead of the cadmium that is used in NiCd batteries.
Almost any liquid or moist object that has enough ions to be electrically conductive can serve as the electrolyte for a cell.