The main materials for carbon negative electrode materials in lithium-ion batteries are mostly carbon materials, such as artificial graphite, natural graphite, mesophase carbon microspheres, petroleum coke, carbon fiber, pyrolysis resin carbon, etc. Tin based negative electrode materials can be divided into two types: tin oxide and tin based composite oxide. Oxides refer to the oxides of various valence metal tin. There are no commercial products. Nitrides do not have commercial products. The alloy category includes tin based alloys, silicon based alloys, germanium based alloys, aluminum based alloys, antimony based alloys, magnesium based alloys, and other alloys, and there are no commercial products. Nano level carbon nanotubes and nano alloy materials. According to the latest market development trends in the lithium battery new energy industry in 2009, many companies have started using nano titanium oxide and nano silicon oxide to add to traditional graphite, tin oxide, and carbon nanotubes, greatly improving the charging and discharging capacity and frequency of lithium batteries Selection method: Lithium thionyl chloride battery pack connected in series. Lithium ion batteries are divided into liquid lithium ion batteries and polymer lithium ion batteries. The electrolyte of lithium-ion batteries is flowing, so they are more unstable than lithium-polymer batteries. They may explode when hit by external forces or when using non-standard chargers. Many portable electronic products such as mobile phones and laptops use lithium batteries. That is to say, many people have a 'bomb' around them. For safety reasons, you must pay attention to the following points when choosing. 1、 Is there a clear indication of the capacity. Batteries without clearly labeled capacity (such as 1000mAh or 1000mAh per hour) are likely to use inferior or recycled batteries. Many cheap batteries in the market are made from recycled battery cores. Although they are cheap, their lifespan is short and their quality is unstable. Improper use may damage the phone. 2、 Is there a guarantee of standby time. Standby time refers to the continuous usage time from the time the battery is loaded into the phone to the next charging. Generally, batteries sold in the market cannot guarantee standby time for customers due to unstable battery quality. Many cheap batteries have short standby time due to the use of poor quality battery cores. 3、 Is a safety protection circuit board installed. Without a protective circuit board, there is a risk of deformation, leakage, and explosion in lithium batteries. In the fierce price competition, companies are seeking lower priced protective circuit boards or simply omitting this device, making the market full of lithium batteries with explosive risks. Consumers cannot distinguish whether there is a protective circuit board from its appearance, so it is best to choose reputable merchants to purchase. On January 19, 2022, the Ministry of Industry and Information Technology will guide relevant units to accelerate the development of lithium battery coding standards. [3]