What materials are used to make lithium-ion batteries?

Lithium Batteries are divided into two types: lithium metal batteries and lithium ion batteries. This is defined by the form of lithium; lithium metal batteries use lithium metal as the electrode, and lithium ion batteries exist in the form of ions in the electrode.

Lithium metal batteries generate electricity by corrosion or oxidation of the lithium metal, which is wasted and cannot be recharged, so they are also called primary batteries. Lithium-ion batteries use the difference in concentration of lithium ions to store and discharge energy, and there is no lithium metal in the battery, so it is also called a lithium secondary battery. At present, it is used in mobile phones, cameras, power tools, electric vehicles, energy storage, communication base stations and other rechargeable lithium batteries, which are lithium-ion batteries. The most commonly used and visible lithium batteries on the general market are lithium-ion batteries, and we are also used to refer to them as lithium batteries, and the lithium batteries described in this article mainly refer to lithium-ion batteries.

First, Lithium Battery classification

1, the two types of classification methods used in the market: according to the pole plate material classification and according to the product appearance classification.

A, according to the pole material classification

Cathode materials: Lithium Iron Phosphate Battery (LFP), lithium cobalt oxide battery (LCO), lithium manganate battery (LMO), (binary battery: lithium nickel manganate/lithium nickel cobaltate), (ternary: lithium nickel cobalt manganate battery (NCM), lithium nickel cobalt aluminate battery (NCA))

Anode materials: lithium titanate battery (LTO), graphene battery, nanocarbon fibre battery.

The graphene concept in the market mainly refers to the graphene-based battery, i.e. the graphene paste is added to the pole film or the graphene coating is added to the diaphragm. Lithium nickelate and magnesium based batteries are basically absent from the market.

B, according to product appearance classification

Divided into: cylindrical, soft bag, square.

Cylindrical and square outer packaging is mostly steel shell or aluminium shell. Soft bag packaging for aluminium-plastic film, in fact, soft bag is also a square, the market is used to aluminium-plastic film packaging called soft bag, and some people will soft bag battery called polymer battery.

For cylindrical lithium-ion batteries, the model number is usually 5 digits. The first two digits are the diameter of the battery, and the middle two digits are the height of the battery. The unit is millimetres. For example, the 18650 lithium battery has a diameter of 18 mm and a height of 65 mm.

C, according to electrolyte material

Lithium-ion batteries are divided into liquid lithium-ion batteries (LIB) and polymer lithium-ion batteries (PLB).

Liquid lithium-ion batteries use liquid electrolytes (currently most power batteries use this type). Polymer Li-ion batteries are replaced by solid polymer electrolytes, which can be "dry" or "colloidal", and most polymer gel electrolytes are currently used. Strictly speaking, solid-state batteries have solid electrodes and electrolytes.

D, according to the practical performance classification of batteries

Power batteries and energy batteries. Energy type batteries are characterised by high energy density and are mainly used for high energy output; power type batteries are characterised by high power density and are mainly used for instantaneous high power output and output batteries. The power energy type lithium battery is accompanied by the emergence of plug-in hybrid vehicles. It requires the battery to store high energy, can support a distance of pure electric driving, but also have good power characteristics when the low power to enter the hybrid mode.

Simple understanding, the energy type is similar to marathon runners, to have stamina, is to have high capacity, the high current discharge performance requirements are not high; Then the power type is a sprinter, fighting is the outbreak, but the stamina must also have, otherwise the capacity is too small to run far.

Second, lithium battery material composition

Four main materials: positive electrode material, negative electrode material, diaphragm, electrolyte

Auxiliary materials: NMP, copper foil, aluminium foil, aluminium case cover, conductive agent, binder, other (EMD), etc.

"Lithium battery" is a type of battery using lithium metal or lithium alloy as the negative electrode material and a non-aqueous electrolyte solution. Lithium metal batteries were first proposed and studied by GiletN Lewis in 1912. In the 1970s, M.S. Hittingham proposed and began to study lithium-ion batteries. Due to the very active chemical properties of lithium metal, the processing, preservation and use of lithium metal have very high environmental requirements. Therefore, lithium batteries have not been used for a long time. With the development of science and technology, lithium batteries have now become the mainstream.

Lithium batteries can be broadly divided into two categories: lithium metal batteries and lithium-ion batteries. Lithium-ion batteries do not contain lithium in the metallic state and are rechargeable. The fifth generation of rechargeable batteries, lithium metal batteries, was born in 1996 and its safety, specific capacity, self-discharge rate and performance/price ratio are better than lithium-ion batteries. Due to its own high technical requirements, only a few countries produce lithium metal batteries.

Carbon anode material

The negative electrode materials actually used in Li-ion batteries are basically carbon materials, such as artificial graphite, natural graphite, mesophase carbon microspheres, petroleum coke, carbon fibre, pyrolytic resin carbon, etc.

Tin-based cathode material

Tin-based anode materials can be divided into tin oxide and tin-based composite oxide two kinds. Oxides refer to oxides of different valence metal tin. There are no commercial products.