You must have noticed that in winter, our phones consume electricity very quickly. Cold weather can indeed affect the performance of lithium polymer batteries. As shown in Figure 1, our lithium battery can experience the following situations when used in a low ambient temperature:
Capacity reduction
The main reason for the lower capacity at low temperatures is the reduced mobility of lithium ions within the electrolyte. Lithium ions are crucial in the chemical reactions that generate energy in lithium polymer batteries. As the temperature decreases, the viscosity of the electrolyte increases, making it more difficult for lithium ions to flow between the electrodes. This reduced fluidity reduces the battery's ability to store and release electrical energy, leading to a decrease in capacity.
loss of voltage
Another factor that causes voltage drop is the high internal resistance of
lithium polymer batteries in cold weather. Internal resistance is an inherent obstacle to the flow of current within a battery. As the temperature decreases, the resistance of battery components (such as electrolytes and electrodes) will increase. This increased resistance hinders the smooth passage of current, resulting in a significant voltage drop, especially under load.
Increased internal stress
Low temperature may cause internal strain within the structure of lithium polymer batteries. Temperature changes can cause material shrinkage and expansion, thereby exerting mechanical stress on electrodes and electrolytes. These forces may cause micro cracks and deformations in the internal structure of the battery, thereby endangering its integrity and potentially damaging long-term performance.
The risk of cell damage
At extremely cold temperatures, the electrolyte in lithium polymer batteries may freeze, leading to battery damage. The freezing of electrolytes can disrupt the ion transport pathway, thereby preventing the occurrence of electrochemical processes. In addition, the expansion of frozen electrolytes may cause physical damage to battery separators and separators, leading to leakage and potential fire problems.
voltage fluctuation
Rapid temperature changes can cause voltage fluctuations in lithium polymer batteries. These changes are caused by the different conductivity and reactivity of battery materials at different temperatures. Sudden temperature changes can disrupt the equilibrium of electrochemical reactions, resulting in voltage spikes or drops. These oscillations can disrupt the functionality of the battery and cause potential safety issues.
Fortunately, technological advancements have promoted the development of low-temperature resistant lithium polymer batteries, addressing pain points related to cold weather.
For example, doping electrode materials with specific elements can improve their conductivity and ion diffusion rate, enabling effective charge transfer even in cold environments. There are also some low-temperature lithium polymer batteries that use internal heating mechanisms. These mechanisms, such as self heating elements or resistance heaters, generate heat within the battery, raising its temperature to a range more suitable for efficient operation. This internal heating helps maintain consistent performance and prevents voltage drop, especially in high current or low temperature environments. These technical measures can generally withstand low temperatures of -40 ℃ or even lower.
Guangzhou Battsys Co., Ltd (NEEQ:837375), was founded in 2006, which is a join-stock high-tech enterprise engaging in ODM and OEM , specially for customized and diverse research&production of lithium-ion battery，BATTSYS annual production capacity is tens of millions battery cells. The products are exported to dozens of countries & regions such as Europe, America & Asia etc.
