English
  • English
Home> Articles>News>What Are the Factors Battery's Performance — Professional Battery Exporter

What Are the Factors Battery's Performance — Professional Battery Exporter

From:CTECHI GROUP Limited     Release time:2018-09-29

Overview:With the rapid development of lithium-ion batteries in the fields of electric vehicles and military industry, the shortcomings of lithium-ion batteries that lithium-ion batteries can not adapt to special low-temperature weather or extreme environment become more and more obvious. At low temperature, the effective discharge capacity and energy of lithium-ion batteries ( 18650 lithium battery 3.7v 2200mah as an example) will be significantly reduced. At the same time, lithium-ion batteries are almost non-rechargeable in the environment below - 10℃, which seriously restricts the application of lithium-ion batteries ( 18650 lithium battery 3.7v 2200mah as an example).

With the rapid development of lithium-ion batteries in the fields of electric vehicles and military industry, the shortcomings of lithium-ion batteries that lithium-ion batteries can not adapt to special low-temperature weather or extreme environment become more and more obvious. At low temperature, the effective discharge capacity and energy of lithium-ion batteries ( 18650 lithium battery 3.7v 2200mah as an example) will be significantly reduced. At the same time, lithium-ion batteries are almost non-rechargeable in the environment below - 10℃, which seriously restricts the application of lithium-ion batteries ( 18650 lithium battery 3.7v 2200mah as an example).

Lithium ion batteries are mainly composed of cathode materials, anode materials, separators and electrolytes. Lithium-ion batteries in low temperature environment have the characteristics of lower discharge voltage plateau, lower discharge capacity, faster capacity decay and poor rate performance. The main factors that restrict the low temperature performance of lithium ion batteries are as follows:

18650 Lithium Battery 3.7v 2200mah

Positive Structure

The three-dimensional structure of cathode materials restricts the diffusion rate of lithium ions, especially at low temperatures. The cathode materials for lithium-ion batteries include commercially available lithium iron phosphate, nickel-cobalt-manganese ternary materials, lithium manganese oxide, lithium cobalt oxide battery and other high-voltage cathode materials such as lithium nickel-manganese oxide, lithium iron-manganese phosphate and lithium vanadium phosphate. Different cathode materials have different three-dimensional structures. At present, lithium iron phosphate, nickel-cobalt-manganese ternary materials and lithium manganate are mainly used as cathode materials for electric vehicle power batteries. Wu Wendi and others studied the discharge performance of lithium ferrous phosphate battery and nickel-cobalt-manganese ternary battery at - 20 ~C. It was found that the discharge capacity of lithium ferric phosphate battery at - 20 ~C was only 67.38% of normal temperature capacity, while that of nickel-cobalt-manganese ternary battery was 70.1%. Du Xiaoli and so on found that the discharge capacity of the lithium manganese battery at - 20 C can reach 83% of the room temperature capacity.

High Melting Point Solvent

Because of the existence of high melting point solvents in the mixed solvents of electrolyte, the viscosity of electrolyte of lithium ion batteries ( aaa lithium ion 1.5v rechargeable batteries as an example) increases at low temperature. When the temperature is too low, the solidification of electrolyte will occur, which leads to the reduction of the transmission rate of lithium ions in the electrolyte.

Diffusion Rate of Lithium-ions

The diffusion rate of lithium ions in graphite negative electrode decreases at low temperature. The influence of graphite anode on the low temperature discharge performance of lithium-ion batteries ( aaa lithium ion 1.5v rechargeable batteries as an example) was studied systematically. It was pointed out that the increase of charge transfer impedance and the decrease of lithium ion diffusion rate in graphite anode were the important factors affecting the low temperature performance of lithium-ion batteries.

SEI Film

At low temperature, the SEI thin film lithium ion battery anode thickens, and the SEI film impedance increases, which results in the decrease of the conduction rate of SEI thin film lithium ion battery. Finally, the charge-discharge polarization of lithium-ion battery at low temperature reduces the charge-discharge efficiency.

Summary

At present, many factors affect the low-temperature performance of lithium-ion batteries, such as the structure of cathode, the transfer rate of lithium ions in various parts of the battery, the thickness and chemical composition of SEI film, and the choice of lithium salts and solvents in the electrolyte.

Low-temperature performance limits the application of lithium-ion batteries in the field of electric vehicles, military industry and extreme environment. Developing lithium-ion batteries with excellent low-temperature performance is an urgent demand in the market.

18650 Lithium Battery 3.7v 2200mah

About Us

We CTECHI Group is a leading manufacturer and professional battery exporter in China, providing best long lasting lithium manganese dioxide batteries, thin film lithium ion battery, 18650 lithium battery 3.7v 2200mah and aaa lithium ion 1.5v rechargeable batteries. We are not only focus on provide single cell but provide battery assembly and do OEM service for customers, CTECHI has captured 80 percent of overseas markets in the past 16 years with more than 2000 reliable customers in our customer management system, which has been being one of the leading enterprises with the most complete category in China's battery industry.


Message BoardPlease write down your question and we will respond to you within 24 hours.