Correct understanding of power banks

Everyone knows about power bank, but do you really understand it? Power bank is also what everyone calls mobile power supply. It is also designed for people who are inconvenient to charge while traveling. So can you really clearly explain some of the features and working principles of the power bank? Let’s increase our knowledge together~

A mobile power supply or mobile charger is a portable charger that can be carried by individuals and can store electric energy by itself. It is mainly used to charge handheld mobile devices and other consumer electronic products (such as wireless phones and laptop computers). It is especially used when there is no external power supply. occasion. Its main components include: a battery used for electrical energy storage, a circuit to stabilize the output voltage (DC-DC converter), and most mobile power supplies have a charger for charging the built-in battery.

The emergence of mobile power supplies was originally used to charge consumer electronic products in situations where there is no external power supply. However, because its output interface is a highly versatile USB interface, it can also be used as other devices that use USB interfaces as power input terminals or Power supply for equipment, such as USB LED lights, USB electric fans, etc.

working principle

The principle of the mobile power supply is simple. When an external power supply can be found, the built-in battery is charged in advance, that is, electric energy is input and stored in the form of chemical energy. When needed, the battery provides energy and generates electric energy, which is converted into voltage. The converter (DC-DC converter) reaches the required voltage, and the output terminal (usually a USB interface) outputs the power to the required equipment for charging or other purposes.

basic component

Power banks have three basic functions, including energy storage, charging and power supply. Other functions are added according to the needs of different designs, uses and convenient operations, such as safety protection, battery status detection and display, etc.

Energy storage (battery)

In order to power other devices without an external power source, the power bank requires a battery for energy storage. Most power banks use lithium-ion batteries (Li-ion) or lithium-ion polymer batteries (Li-PO). A small number of power banks use nickel-metal hydride batteries (Ni-MH). In the early days, some power banks also used Use primary batteries.

Lithium-ion batteries (Li-ion) or lithium-ion polymer batteries (Li-PO) have the highest energy density whether by weight or volume, that is, they are the lightest and thinnest. In addition, lithium-ion/ion polymer batteries are also more efficient during charging and discharging (less energy/electricity is wasted). However, the price is also the highest among these batteries, and because overcharging or over-discharging can easily cause permanent damage to the battery, more sophisticated electronic circuits are required to control charging and discharging. Since lithium-ion/ion polymer batteries will spontaneously ignite at high temperatures, safety and stability have become extremely important requirements. A reliable safety protection circuit is required to prevent any over-temperature conditions.

Lithium-ion batteries have a hard shell, but lithium-ion polymer batteries do not, so lithium-ion batteries will theoretically be slightly heavier. Lithium-ion polymer batteries do not have a hard shell, so they can be made into specific sizes to match the appearance, but lithium-ion batteries Polymer batteries will expand slightly when fully charged, so space needs to be reserved during design to avoid danger caused by excessive pressure within the battery. The above is the technical analysis related to power bank, I hope it can help you.