Why is the battery in winter?

　　Author ：Iflowpower – Portable Power Station Supplier

The important factor is the following aspects: 1. Effect of electrolyte on battery low temperature 1.1 Conductivity conductivity is an important parameter to measure electrolyte performance, which determines the internal resistance and magnification characteristics of the electrode, and higher conductivity is Essential conditions for achieving good low temperature performance of lithium ion batteries.

From an organic solvent perspective, important factors affecting conductivity are the dielectric constant and viscosity of the solvent. The larger the solvent dielectric constant, the weaker the electrostatic use of lithium ions and the anionic, the easier to dissoderate, the number of free ions increase. The viscosity of the solvent affects the mobility of free ions, the larger the viscosity, the smaller the mobility, the smaller the conductivity;.

1.2 Solid electrolyte phase interface (SEI film) The electrolyte composition not only determines the ion conductivity of the LR electrolyte, but also affects the formation of the SEI film. The nature of the SEI membrane, such as the pore, electron and ionic conductivity, the irreversible capacity, low temperature performance, cycle performance and safety performance of the battery.

Excellent SE1 membrane should have an organic solvent insoluble, allowed to freely enter and exit electrodes and solvent molecules cannot pass, thereby preventing solvent molecules from circulating electrode damage, improves electrode cycle life. Add an appropriate amount of film-forming additive to a lithium ion battery electrolyte, reduce the SEI film resistance, improve the low temperature performance of the battery. 2 The effect of electrode material particles on low temperature performance is significantly improved by reducing the particle size of the electrode material.

3 The charge transfer resistor affects low temperature performance The charge and discharge process of the lithium ion battery includes the transmission process of the lithium ion in the solid phase liquid phase, and includes the charge transfer process of the electrode / electrolyte interface, characterizing the resistance of the process is called Charge transmission resistance, referred to as electrochemical reaction resistance. The electrochemical reaction resistance is bigger, indicating that the electrochemical reaction is not easy, or the same current, the electrochemical reaction resistance is solarish, the more the over-potential is bigger, that is, the promotion force is bigger. The factors affecting the low temperature performance of lithium ion batteries are more complicated, and there is no uniformity.

SEI film resistance, interface charge transfer resistance, diffusion coefficient inside the lithium ion storage electrode, etc., may become an important factor affecting low temperature performance of potassium ion batteries in a particular system. Alternatively, such as the structure of the battery, the particle size of the electrode material, the preparation process, the electrolyte, the positive and negative electrode material, the electrode surface area, the porosity, the electrode density, the thickness, the porosity and the porosity of the adhesive to the electrolyte Wetness, etc.

, these factors may become an important factor affecting the low temperature performance of lithium ion batteries.