1. Limitation of electrode material
The battery can not meet the requirements of high temperature and low temperature at the same time mainly for the following reasons: 1. High temperature impact In a high temperature environment, the chemical activity of the electrode material will be enhanced. For example, the positive electrode material in lithium-ion batteries may undergo structural changes or side reactions with the electrolyte, resulting in accelerated capacity decay and shortened cycle life. At the same time, high temperature may also accelerate the diffusion of lithium ions in the electrode material, which is conducive to the charge and discharge performance of the battery to a certain extent, but it will also increase the polarization of the electrode material and reduce the stability and safety of the battery. 2. Low temperature influence At low temperature, the conductivity of the electrode material will decrease significantly. The diffusion rate of lithium ions in the electrode material is slow, which increases the internal resistance of the battery and deteriorates the charge-discharge performance. In addition, low temperatures may also lead to the formation of a passivation film on the surface of the electrode material, further hindering the insertion and removal of lithium ions, reducing the capacity and power output of the battery.
2. Electrolyte limitation
(1) High temperature effect High temperature will reduce the viscosity of the electrolyte and increase the ionic conductivity, but it will also accelerate the decomposition and volatilization of the electrolyte. This will not only reduce the performance of the battery, but also may cause safety problems, such as leakage, fire and so on. Moreover, the stability of the interface between the electrolyte and the electrode material will also be affected at high temperatures, and it is easy to form a poor solid electrolyte interface (SEI) film, which further damages the performance of the battery.
(2) Low temperature influence At low temperature, the viscosity of the electrolyte will increase, and the ionic conductivity will drop sharply. This makes the migration of lithium ions in the electrolyte difficult, resulting in increased internal resistance of the battery and severely limited charge-discharge performance.
In addition, low temperatures may also make the electrolyte solidify or crystallize, completely losing the ability to conduct ions, so that the battery can not work properly.
3. Limitations of battery structure and packaging
(1) Influence of high temperature
High temperature will increase the pressure inside the battery, causing great pressure on the packaging structure of the battery. If the strength of the packaging material is not enough or the sealing performance is not good, it may lead to battery leakage, gas and even explosion. At the same time, high temperatures will also make the thermal management of the battery more difficult, requiring a more complex cooling system to maintain the normal operating temperature of the battery.
At low temperatures, the volume of the battery will shrink, which may cause the structure inside the battery to loosen, affecting the contact between the electrode and the electrolyte, thereby reducing the performance of the battery. Moreover, the low temperature will also make the battery shell material brittle, vulnerable to external damage, affecting the safety and reliability of the battery.
In summary, due to the limitations of electrode materials, electrolytes, and battery structure and packaging, it is difficult for batteries to meet the requirements of high and low temperatures at the same time. In order to solve this problem, scientists are constantly researching and developing new battery materials and technologies to improve the performance and stability of batteries at different temperatures.
