Battery polarization

When the battery has a current, the phenomenon that the electrode deviates from the equilibrium electrode potential is called electrode polarization. Battery polarization is present in common batteries such as lead-acid batteries, lithium batteries, and nickel-metal hydride batteries.
A battery is a device for energy conversion and storage. It converts chemical or physical energy into electrical energy through a reaction. A battery is a kind of chemical power source. It consists of two different components of electrochemically active electrodes, which are composed of positive and negative electrodes. The two electrodes are immersed in an electrolyte that can provide media conduction. When connected to an external carrier, it is converted by Internal chemical energy to provide energy. As an electrical storage device, when two metals (usually metals with different properties) are immersed in the electrolyte, they can conduct electricity and generate a certain electromotive force between the "plates". The magnitude (or voltage) of the electromotive force is related to the metal used, and the electromotive force of different types of batteries is also different.
The performance parameters of the battery mainly include electromotive force, capacity, specific energy and resistance. The electromotive force is equal to the work done by the non-electrostatic force (chemical force) of the battery when the positive charge is moved from the inside of the battery to the positive electrode. The electromotive force depends on the chemistry of the electrode material and is independent of the size of the battery. The total amount of charge that the battery can output is the capacity of the battery, usually in ampere-hours. In a battery reaction, the electrical energy produced by 1 kilogram of reactive species is called the theoretical specific energy of the battery. The actual specific energy of the battery is smaller than the theoretical specific energy. Because the reactants in the battery are not completely reacted according to the battery reaction, and the internal resistance of the battery also causes the electromotive force to drop, the battery with higher energy is often referred to as a high-energy battery. The larger the area of ​​the battery, the smaller the internal resistance.
The energy storage of a battery is limited. The total amount of charge that a battery can output is called its capacity. It is usually measured in ampere-hours. It is also a performance parameter of the battery. The capacity of the battery is related to the amount of electrode material, that is, to the volume of the electrode.
Practical chemical batteries can be divided into two basic types: primary batteries and batteries. The current can be generated after the primary battery is made, but it is discarded when the discharge is completed. The battery is also called a secondary battery. It must be charged before use. It can be discharged after charging. It can be recharged after the discharge is completed. When the battery is charged, the electrical energy is converted into chemical energy; when discharged, the chemical energy is converted into electrical energy.