The cornerstone of new energy: Read the development and principle of lithium batteries

Lithium batteries are a common type of rechargeable battery whose electrochemical reaction is based on the migration of lithium ions between the positive and negative electrodes. Lithium batteries have the advantages of high energy density, long life and low self-discharge rate, so they are widely used in various electronic devices and electric vehicles.

The working principle of lithium batteries is based on the migration of lithium ions between the positive and negative electrodes. During the charging process, lithium ions are released from the positive material (usually an oxide such as lithium cobaltate), pass through the electrolyte, and are then inserted into the negative material (usually a carbon material). During the discharge process, lithium ions are separated from the negative material and move through the electrolyte to the positive material, generating current and electrical energy, which drives the external equipment to work.

The working principle of lithium batteries can be simplified into the following steps:

1. During the charging process, the negative electrode of the lithium battery will absorb external electrons. In order to remain electrically neutral, the positive electrode will be forced to release electrons to the outside, and the lithium ions that have lost electrons will be attracted to the negative electrode and move through the electrolyte to the negative electrode. In this way, the negative electrode replenishes electrons and stores lithium ions.

2. When discharging, the electrons return to the positive electrode through the external circuit, and the lithium ions are also removed from the negative electrode material, releasing the stored electrical energy in the process, and moving back to the positive electrode through the electrolyte, and the electrons are combined to participate in the reduction reaction to restore the structure of the lithium compound.

3. In the process of charge and discharge, in fact, it is the process of lithium ions chasing electrons, during which the storage and release of electrical energy is achieved.

The development of lithium batteries has gone through multiple stages. In the early 1970s, lithium metal batteries were first introduced, but due to the high activity and safety issues of lithium metal, their application scope was limited. Subsequently, lithium-ion batteries have become the mainstream technology, which uses non-metallic lithium compounds as positive electrode materials to solve the safety problem of lithium metal batteries. In the 1990s, lithium polymer batteries appeared, using polymer gels as electrolytes, improving the safety and energy density of batteries. In recent years, new lithium battery technologies such as lithium-sulfur batteries and solid-state lithium batteries have also been developing.

At present, lithium-ion batteries are still the most commonly used and most mature battery technology. It has high energy density, long cycle life and low self-discharge rate, and is widely used in mobile phones, notebook computers, electric vehicles and other fields. In addition, lithium polymer batteries are also widely used in fields such as thin and light devices and wireless headphones, due to their high energy density and thin design characteristics.

China has made remarkable progress in the field of lithium batteries. China is one of the world's largest producers and consumers of lithium batteries. China's lithium battery industry chain is complete, from raw material procurement to battery manufacturing has a certain scale and technical strength. China's lithium battery companies have made important progress in technology research and development, production capacity and market share. In addition, the Chinese government has also introduced a series of support policies to encourage the development and innovation of the lithium battery industry. Lithium batteries have become a major energy solution in areas such as electronic devices and electric vehicles.