Why Lithium-Ion Battery Performance Drops When Left on Charge
Have you ever left your device charging while it was already fully charged? Did you wonder whether it was affecting the battery's performance or longevity? In this article, we will explore the reasons behind the degradation of a lithium-ion battery's performance when left on charge, especially when it is fully charged. We will discuss the modern approaches to battery charging, the impact of heat, and the role of frequent charge/discharge cycles.
Modern Chargers and Smart Charging Control
One of the earliest pieces of advice given to users was to be careful about leaving batteries on charge for long periods. However, modern lithium-ion batteries have advanced to a point where the charging process is much more controlled and efficient. Unlike older battery technologies that relied on simple trickle charging strategies, modern battery management systems include smart charging controllers.
These smart charging controllers automatically shut down the charging process once the battery reaches the optimal charge level. The rationale behind this is that fully charged batteries are more prone to degradation, primarily due to heat buildup. Additionally, leaving a battery fully charged for extended periods can lead to unnecessary heat, which can significantly shorten its lifespan.
Impact of Heat on Battery Performance
Batteries, especially lithium-ion and lithium-polymer batteries, are highly susceptible to heat. Excessive heat can damage the battery's internal components and degrade its overall performance. As the battery begins to overcharge, the temperature starts to rise. This overheating not only reduces the battery's efficiency but can also cause issues such as swelling, deformation, or, in extreme cases, the venting of electrolyte, which can lead to further damage.
Smart Batteries and Self-Discharge Mechanism
Modern batteries are designed with self-discharge mechanisms to mitigate the effects of long-term storage at full charge. These smart batteries are equipped with sensors that can detect when the battery has been left for extended periods in a fully charged state. In response, they may slowly begin to discharge the battery to prevent excessive heat buildup.
Why Lithium-Ion Batteries Don't Like to Sit at 100% for Too Long
One of the primary reasons lithium-ion batteries should not remain continuously charged at 100% is the risk of overcharging. When a battery is overcharged, it starts to undergo a process known as overvoltage. This condition can cause physical and chemical changes within the battery, leading to the failure of internal cells and a reduction in overall battery life.
To avoid overcharging, the charging system is designed with safety mechanisms to cut off the charging process once the battery reaches its maximum capacity. This ensures that the battery does not continue to draw current, leading to further heat generation and potential damage.
Conclusion
While modern battery technologies have made significant progress in improving battery life and performance, it is still crucial to follow best practices to ensure optimal functionality. Leaving a fully charged lithium-ion battery for long periods can lead to heat buildup, which can degrade the battery's performance and shorten its lifespan. By understanding the mechanisms behind battery charging and the potential hazards of overcharging, you can help extend the life of your battery and ensure your devices perform at their best.