What are the main safety features of Polymer Lithium-Ion Battery?
Publish Time: 2024-09-10
Electrolyte properties:High stability: Polymer Lithium-Ion Battery uses polymer gel film as electrolyte. Compared with the liquid electrolyte of traditional liquid lithium battery, polymer gel is more stable in the event of a safety accident. Even in extreme cases, such as when the battery is impacted by external force or overheated, polymer gel is not prone to violent chemical reactions, reducing the risk of fire and explosion.Not easy to leak: Polymer gel has a certain viscosity and flexibility, can be well attached to the positive and negative electrode materials of the battery, and can effectively prevent the leakage of electrolyte. When the battery shell is broken or the seal is poor, the liquid electrolyte is easy to leak out, and it may cause dangers such as combustion after contact with air or other substances.Battery structure design:Multi-layer isolation design: Modern Polymer Lithium-Ion Battery usually uses multi-layer polymer film for isolation. This design can effectively prevent short circuits between positive and negative electrodes. The multi-layer isolation film can increase the insulation between the positive and negative electrodes, and reduce the possibility of direct contact between the positive and negative electrodes even when the battery is squeezed or collided, thereby reducing the safety hazards caused by internal short circuits in the battery.Advantages of soft packaging: The battery packaging adopts a composite structure of metal aluminum foil and polymer film. Metal aluminum foil can effectively block external moisture and oxygen, slow down the speed of chemical reactions inside the battery, and reduce corrosion and aging of the battery due to moisture or contact with oxygen; at the same time, the polymer film can ensure the normal flow of electrolytes inside the battery and maintain the normal operation of the battery.Safety protection mechanism:Overcharge protection: Polymer Lithium-Ion Battery is usually equipped with an overcharge protection circuit. When the battery charge reaches the set voltage upper limit, the protection circuit will automatically cut off the charging current to prevent the battery from overcharging. Overcharging may cause problems such as increased internal battery temperature and damage to the electrode material structure, which may cause safety accidents in severe cases. The overcharge protection circuit can effectively avoid this situation.Over-discharge protection: Similarly, the battery also has an over-discharge protection function. When the battery is discharged to the set voltage lower limit, the protection circuit will stop the battery from discharging to protect the positive and negative electrode materials of the battery from excessive damage. Excessive discharge will reduce the capacity of the battery, affect the service life of the battery, and may also cause safety problems in some cases.Thermal stability:High temperature resistance: The material and structural design of Polymer Lithium-Ion Battery make it have good high temperature resistance. Within the normal operating temperature range, the battery can work stably and will not cause safety problems due to temperature increase. Even in a high temperature environment, the battery can maintain relatively stable performance and is not prone to dangerous situations such as thermal runaway.Good heat dissipation: The structural design of the battery is conducive to heat dissipation. For example, the soft packaging material of the battery has a certain thermal conductivity, which can transfer the heat generated inside the battery to the outside in time and reduce the temperature inside the battery. Good heat dissipation performance can avoid safety accidents caused by heat accumulation in the battery.Gas release mechanism:Pressure release: When an abnormal situation occurs inside the battery, such as overheating, short circuit, etc., and a large amount of gas is generated, the soft packaging of the Polymer Lithium-Ion Battery can break through the shell earlier, release the internal pressure, and prevent excessive gas accumulation from causing the battery to rupture violently or explode. In contrast, traditional liquid lithium batteries use metal shells, and the internal pressure is not easy to release. Once a safety problem occurs, it may have more serious consequences.
