The word "battery" comes from the Latin "accumulo" - to accumulate, collect. That is, this device is intended for the accumulation and conservation of electricity. In the article, we consider in more detail the types of these devices used for screwdrivers (household and professional). The most important parameter of this device is capacity. It displays the period of time for which the battery is able to provide the declared amperage. The second most important parameter is voltage. Batteries for a screwdriver have a voltage of 9V to 18V.
The following types of devices exist:
Nickel-cadmium batteries for a screwdriver. They have a long service life (up to 1000 discharge / charge cycles); short time required for recharging; well tolerate high / low temperatures and high charging current. The disadvantages include high self-discharge rate (if the battery has not been used for a long time, recharging will be required), the complexity of disposal. Accurate observance of charge / discharge rules is also necessary: if a battery that is not fully discharged is put on recharging, crystals will form on the plates, which reduce the capacity (the so-called "memory effect").
Nickel-metal hydride batteries for screwdrivers. Advantages: the operating life is about 1,500 charge / discharge cycles, the absence of a “memory effect", and increased capacity. The disadvantages include the high cost, poor tolerance of low or high temperatures and the fact that they do not tolerate a high discharge rate (long-term operation at high power).
Lithium-ion batteries for a screwdriver. The positive aspects include: a large capacity, the absence of a "memory effect" and self-discharge, the short time required for a charge. Disadvantages: you can not allow a complete discharge of the battery (after several full discharges, you may need a new battery); during long-term storage, it loses part of the capacity (when buying a tool, pay attention to the manufacturing date, otherwise you will get a device that has completely different parameters that are stated); responds poorly to low temperatures.
Due to the differences, all batteries are conventionally divided into models for household screwdrivers and for professional ones. It is clear why: professional should provide longer work, while having a shorter charge time. If you plan to work with a power tool constantly, you should think about purchasing a second battery: while one is in operation, the second is on charge. In this way, you can provide a decent amount of time for smooth operation. When choosing a battery, pay attention to the fact that some models of the tool can work with several types of similar devices (information on this is available in the product passport).
Workmanship and operational reliability are decisive indicators that should be taken into account when choosing. With equal technical characteristics, preference is often given to more well-known brands, despite the fact that the price is higher. For example, a Bosch screwdriver battery is in high demand due to its reputation as a manufacturer. But this does not mean that devices of other brands work worse, or are made less quality. Another sales leader - a battery for Hitachi screwdrivers - is also in demand due to the “untwisted” brand.