The negative electrode of a lithium-ion battery is made by uniformly coating both sides of a copper foil with a paste-like adhesive, which is a mixture of carbon or non-carbon materials, binders and additives, and then drying and rolling it.
The negative electrode material is the main component of a lithium-ion battery that stores lithium, enabling lithium ions to be inserted and extracted during charging and discharging. During charging, lithium atoms in the positive electrode ionize into lithium ions and electrons, and these lithium ions move towards the negative electrode to combine with electrons to form lithium atoms. During discharging, lithium atoms ionize from the graphite crystal on the surface of the negative electrode into lithium ions and electrons, and then combine at the positive electrode to form lithium atoms.
In lithium-ion battery materials, the anode material is a crucial component, significantly impacting the overall performance of the lithium battery. Currently, anode materials are mainly divided into two categories: commercially available carbon materials, such as natural graphite and soft carbon, and non-carbon anode materials that are still under research but have promising market prospects, such as silicon-based materials, alloy materials, and tin-gold materials.
1. Carbon anode materials
This type of material offers a well-balanced performance in terms of energy density, cycle life, and cost, and is a key material driving the development of lithium-ion batteries. Carbon materials can be divided into two main categories: graphitized carbon materials and hard carbon. The former mainly includes artificial graphite and natural graphite.
2. Natural graphite
Natural graphite also has many advantages, including high crystallinity, numerous embedding sites, and low price, making it a relatively ideal material for lithium-ion batteries. However, it also has certain drawbacks, such as poor compatibility with electrolytes and numerous surface defects during pulverization, all of which will have a significant adverse impact on its charging or discharging performance.
