Simple analysis of the structure and working principle of lithium batteries

The structure and working principle of lithium batteries are analyzed in detail. Lithium batteries are divided into lithium batteries and lithium batteries. Mobile phones and notebook computers use lithium batteries, commonly known as lithium batteries. Real lithium batteries are very dangerous and are rarely used in everyday electronic products. Lithium battery is a kind of rechargeable battery, which mainly relies on lithium ions to move between the positive and negative electrodes. During the charging and discharging process, Li+ is inserted back and forth between the two electrodes and back inserted. In a rechargeable battery, Li+ is removed from the positive electrode and inserted into the negative electrode through the electrolyte, in a lithium-rich state. When unloading, the situation is just the opposite. Lithium-containing data is generally used as the electrode of the battery, which is a representative of modern high-function batteries. How does a lithium battery work? A lithium battery uses carbon data as the negative electrode and a lithium-containing compound as the positive electrode. There is no metallic lithium. As long as it is lithium ion, this is a lithium battery. Lithium battery refers to lithium ion intercalation compound as a positive data battery. The charging and discharging process of lithium batteries is the process of intercalation and deintercalation of lithium ions. The process of embedding and de-embedding of lithium ions is accompanied by the embedding and de-embedding of lithium ions and equivalent electrons (traditionally, the positive electrode is represented by embedding or de-embedding, and the negative electrode is represented by insertion or de-embedding). During the charging and discharging process, lithium ions are inserted/de-intercalated and thrust/de-intercalated back and forth between the positive electrode and the negative electrode, which is vividly called the rocking chair battery. When the battery is charged, lithium ions are formed at the positive electrode of the battery, and the resulting lithium ions pass through the electrolyte to the negative electrode. Carbon is the negative electrode and has a layered structure with many micropores. Lithium ions reaching the negative electrode are inserted into the micropores of the carbon layer. The more lithium ions are inserted, the greater the charging capacity. Similarly, when the battery is discharged (the process we use the battery), the lithium ions embedded in the carbon of the negative electrode will come out and return to the positive electrode. The more lithium ions in the cathode, the greater the discharge capacity. The charging current of lithium batteries is generally set between 0.2c and 1C. The higher the current, the faster the charging, and the greater the heating of the battery. Moreover, when overcurrent charging, the capacity is not satisfied because of the electrochemical response demand torque inside the battery. Just like pouring beer, pouring too fast will burst the foam, but you are dissatisfied. Regarding the battery, normal use is the process of discharging. The most important requirement of lithium battery discharge is that the discharge current should not be too large. Excessive current will cause the internal heating of the battery, which may cause permanent damage. On mobile phones, this is no problem and cannot be considered. Secondly, be sure not to over-discharge! Lithium batteries are most afraid of over-discharge. Once the discharge voltage is lower than 2.7V, the battery may be wasted. Fortunately, a protection circuit has been installed inside the battery of the mobile phone. The voltage is not low enough to damage the battery, and the protection circuit will function and stop discharging. It can be seen from the figure that the larger the discharge current of the battery, the smaller the discharge capacity and the faster the voltage drop. Lithium battery structure positive electrode: active material, conductive agent, solvent, binder, matrix. When the battery is discharged, the electrode that takes electrons from the external circuit, then the electrode triggers and resumes its response. It is usually a high potential electrode. Lithium cobalt oxide battery, lithium manganese oxide electrode. Negative electrode: active material (graphite, MCMB, CMS), binder, solvent, matrix. When the battery is discharged, the electrodes that transport electrons to the external circuit will react with oxidation. Graphite electrodes in lithium batteries are generally low-potential electrodes. The gap sets up a barrier between the north and south poles of the battery as a shielding electrode device to prevent the active materials of the north and south poles from directly contacting and forming a short circuit inside the battery. But this barrier still has to allow charged ions to pass through to form a channel. Alienation requirements: 1. High ion transmission rate 2. Appropriate mechanical strength 3. It is an insulator 4. No reaction with electrolyte and electrodes Statement: Some pictures and content of articles published on this site are from the Internet. Please contact us if there is any infringement Delete the previous article: Why hasn't graphene batteries replaced lithium batteries?