What impact will the lithium battery have after being put aside for a long time?

When the lithium battery is idle, due to the nature of the battery itself, self-discharge, passivation of positive and negative electrode materials, electrolyte decomposition and other phenomena will occur. The instability of the negative SEI will lead to the rapid decline of the negative active substance, which is easy to cause the precipitation of lithium metal. At the same time, different electrolyte components have different effects on the attenuation of electrode materials. Therefore, it is particularly important for lithium batteries to have good long-term storage performance. Lithium-ion battery is a relatively complex electrochemical system. After a long period of storage, the internal balance will gradually change. 

When accumulated to a certain extent, lithium batteries tend to undergo the following changes:

1. Physical characteristics
According to the actual proof after the storage time of the lithium battery, the physical characteristics of the battery (appearance, size, weight, etc.) will change to a certain extent, especially the appearance characteristics. This trend is more obvious when the temperature and humidity of the storage environment are not good. In the case of high humidity, the importance of lithium batteries after long-term storage is significantly higher than that of batteries placed under low humidity conditions. For example, the steel shell of the battery is prone to rust in the case of high humidity, resulting in a slight improvement in quality. Rust will not affect the internal state of the battery, but will directly affect the shipment of the product and may have a negative impact on the matching electronic components.

2. Electrochemical characteristics

● Capacity, long-term storage lithium battery capacity changes are mainly reflected in two points: first, the battery capacity decline, mainly caused by self-discharge; The other is the reduction of irreversible capacity, which mainly depends on the irreversible consumption reaction between the chemical systems inside the battery. Self-discharge is unavoidable in all lithium-ion batteries.
● Internal resistance. For long-term storage of lithium batteries, the resistance tends to increase with the increase of storage time. Exceeding a certain internal resistance will cause the internal battery to exceed the benchmark and be scrapped or degraded. Therefore, it is necessary to pay attention to the resistance change of the battery during long-term storage.
● Discharge characteristics: The discharge characteristics of lithium-ion batteries show a downward trend after long-term storage. The low temperature performance of batteries stored for a long time is significantly reduced.

How to store lithium batteries for a long time?

The life of a lithium battery is affected by the operating temperature and ambient humidity. High temperature and humidity will accelerate the life of the lithium battery of the rechargeable battery. It is recommended to store rechargeable batteries in a dry natural environment between 10°C and 35°C. The lithium battery should be charged with 50% to 60% of the power if it is not used for a long time, and should be removed from the instrument and stored in a dry and cool environment. The battery should be charged every 3 months to avoid excessive storage time and self-discharge of the battery. Too low, resulting in irreversible capacity loss. If the lithium battery emits odor, heat, discoloration, deformation, or any abnormality during use, storage, or charging, remove the battery from the device or charger immediately and stop using it.

Storage requirements for lithium iron phosphate batteries

1, lithium iron phosphate battery can be based on the technical requirements of the product itself, using three-dimensional shelves for storage, which is conducive to cost control and the utilization of storage space.
2, lithium iron phosphate battery in storage should avoid due to stacking, extrusion deformation, or battery product damage and leakage.
3, lithium iron phosphate batteries should be stored in a place that is not exposed to direct sunlight or rain. If the battery gets wet, the insulation resistance will drop and self-discharge and chlorination may occur. Rising temperatures can impair the normal function of the battery.
4, the use of safe storage or transportation of packaging, such as ordinary wooden boxes, corrugated boxes, PVG boxes, etc., to ensure the maximum degree of safe storage of goods.
5, develop a variety of lithium iron phosphate battery accident emergency plans, and carry out regular drills if conditions permit.
Therefore, in order to make full use of the energy efficiency of lithium batteries, in the daily use and storage process, we must pay attention to the maintenance of lithium batteries and the knowledge of how to store lithium batteries for a long time.