To prevent the battery from being damaged due to improper usage, a single lithium-ion battery incorporates a triple protection mechanism. The first aspect involves utilizing a switching element. In the event of a surge in battery temperature, the internal resistance increases, triggering an automatic shutdown of the power supply to avert any potential hazards. Additionally, the separator features micro-scale pores that can dissolve autonomously. This dissolution blocks the passage of lithium ions and effectively halts any internal reactions within the battery. Lastly, a safety valve is implemented, commonly referred to as the vent hole situated atop the battery. When the internal pressure surpasses a preset threshold, this safety valve promptly opens, ensuring the battery's safety and integrity. By integrating these precautionary measures, the battery is adequately shielded from discharging or charging issues, thereby enhancing overall safety.
In certain cases, even with safety control measures in place, the control system can malfunction due to various factors. This could be a result of either the absence of a safety valve or the gas being unable to release in a timely manner through the safety valve. Consequently, the battery's internal pressure will experience a rapid increase, ultimately leading to an explosion.
Safety is a crucial consideration when it comes to lithium-ion batteries. In general, the more energy a battery can store, the less safe it tends to be. This is because as the battery's capacity increases, its volume also increases, which in turn hampers its ability to dissipate heat effectively. As a result, the chances of accidents occurring increase significantly.
For mobile phone lithium-ion batteries, it is imperative that the probability of a safety incident is kept below one in a million. This stringent requirement is not only necessary for consumer trust but also the minimum standard acceptable to the public.
However, when it comes to large-capacity lithium-ion batteries used in automobiles, ensuring forced heat dissipation becomes even more crucial. With higher energy storage capabilities, these batteries must be able to dissipate heat efficiently to mitigate safety concerns. Overall, prioritizing safety measures in lithium-ion batteries remains a paramount concern across different applications.
By opting for electrode materials that are comparatively safer and utilizing lithium manganate materials, the molecular structure of the battery is designed in such a way that once it is fully charged, the lithium ions of the positive electrode are entirely incorporated in the carbon pores of the negative electrode, thus effectively preventing the formation of dendrites. Additionally, the steady structure of lithium manganate results in much lower oxidation performance than that of lithium cobalt oxide, and its decomposition temperature exceeds 100 °C of lithium cobalt oxide, making it less prone to combustion or explosion due to the precipitation of metallic lithium.