Types and precautions for electrolyte lithium battery electrolyte

Autor: Iflowpower - Dodavatel přenosných elektráren

The role of the electrolyte in the lithium battery is better than the importance of the blood, and is the medium in the lithium battery in the lithium battery. It does not have electronics flow, and it will not There is such a battery, so its importance is self-evident. Classification of lithium battery electrolyte species The electrolyte of the primary use of lithium batteries is divided into liquid electrolytes and solid electrolytes, and liquid electrolytes are commonly known as electrolyte, mainly in cylindrical and square lithium batteries; solid electrolytes are also known as polymer electrolytes At present, it is mainly applied to the soft bag battery, and there is a very small number of lithium batteries to use solid-state electrolytes because the solid electrolyte is more expensive than liquid electrolyte, so it has not been widely used in a large number of lithium batteries.

1. The selection of liquid electrolyte electrolyte on the performance of the lithium battery is very high, it must be chemically stable performance, especially under higher potentials and higher temperature environments, which is not easy to decompose, with high ion conductivity. (> 10-3s / cm), and the overhead material must be inert, cannot invade them.

Since the charge discharge potential of the lithium ion battery is high and the anode material is embedded with a large chemically active lithium, the electrolyte must use an organic compound without containing water. However, the organic matter ion conductivity is not good, so the soluble conductive salt is added to the organic solvent to increase ion conductivity. At present, the lithium-ion battery is mainly used in liquid electrolytes, and the solvent is anhydrous organic matter such as EC, PC, DMC, DEC, and mostly mixed solvents, such as EC / DMC and PC / DMC, etc.

Conductive salts include Liclo4, LiPF6, LIBF6, LIASF6, etc., their conductivity is sequentially LIASF6> LIPF6> Liclo4> LIBF6. Liclo4 is generally limited to experimental studies due to high oxidative properties, generally only limited to experimental studies; LIASF6 ion conductivity is more purified and stabilized, but contains toxic AS, use limited; LIBF6 chemistry And the thermal stability is not good and the conductivity is not high, although the LIPF6 will decompose, but has a high ion conductivity, so the current lithium-ion battery is basically using LiPF6.

At present, most of the electrolyte used in commercial lithium batteries use LiPF6 EC / DMC, which has high ion conductivity and better electrochemical stability. 2, solid electrolyte uses metal lithium directly as an anode material having a high reversible capacity, its theoretical capacity of up to 3862mAh ¡¤ g, is a twiceide of graphite material, the price is also low, is seen as a new generation of lithium batteries Attractive anode material, but will produce lithium. The use of solid electrolytes as ions can inhibit the growth of lithium lithium, so that metal lithium is used as an anode material.

In addition, the use of solid electrolytes can avoid the disadvantages of liquid electrolyte leakage, and the battery can be made more thin (only 0.1 mm thick), high energy density, and a small volume of high energy cells. Destructive experiments show that the solid-state lithium battery is highly safe, nail, heating (200 ¡ã C), short circuit and overcharge (600%), etc.

Question, while solid-state battery has no other safety problems in addition to internal temperature, there is no other safety problem. The solid polymer electrolyte has good flexibility, film forming, stability, low cost, etc., which can be used as a positive and negative electrode spacer in which it can be used as a electrolyte of transfer ions.

Solid polymer electrolyte is generally divided into dry solid polymer electrolyte (SPE) and gel polymer electrolyte (GPE). The SPE solid polymer electrolyte is mainly based on polyethylene oxide (PEO), which is that the ion conductivity is low, only 10-40 cm at 100 ¡ã C. The ion conduction in the SPE is mainly in an amorphous region, and the transfer migration is transferred by means of a polymer chain.

A liquid organic solvent having a low relative molecular mass of a high dielectric constant in a solid polymer electrolyte such as a PC can greatly increase the solubility of the conductive salt, which is a GPE gel polymer electrolyte, which has very good at room temperature. High ion conductivity, but in the process of use. Gel polymer lithium ion battery has been commercialized.

Lithium battery electrolyte Precautions 1 Leak or other dangers. Be sure to wear a protective eye mask when you take over, and you must use a dedicated quick opening connector. 2 Using a glassware, the main component of the glass is silicon oxide, silicon oxide and hydrofluoric acid to form corrosion, volatile gas tetrafluorinated silicon, which is poisoned to cause injury to people.

3, the electrolyte container and pipeline materials that can be used on site include: stainless steel, plastic PP / PE, tetrafluoroethylene, etc. 4, this product is harmful to the human body, slightly stimulating and anesthesia. Avoid direct contact during use.

Lithium battery electrolyte has gradually replaced imported products after entering the market in 2002. The quality of the product of lithium-ion battery electrolyte is also constantly improving and improving. Its market development prospect is still very vast.

Although the ionic conductivity of solid electrolyte is unable to match the carbonate liquid electrolyte, the solid electrolyte is still one of the mainstream research and development directions of the future lithium battery electroly.