Storage of rechargeable batteries, rechargeable batteries, batteries for mobile equipment

Batteries fall into the category of “perishable products”, starting to lose their quality immediately after production. Although the degree of degradation for some types of batteries is quite low, it is still not recommended to store them for a long period of time before use.

All battery types should be stored in a dry and cool place. We can recommend storage of batteries in the refrigerator (but not in the freezer, because not all types of batteries can withstand storage at freezing temperatures). When stored in a cool place, place the battery in a plastic bag to protect it from moisture condensation.

NiCd batteries can be stored in an unattended state for up to five years. But for best results, before storage, fully charge the battery, then discharge to zero voltage and then short-circuit its terminals. If this procedure is burdensome, discharge the battery up to one volt per cell and store in a dry, cool place. Fully charged NiCd batteries during storage are subject to self-discharge, which leads to the formation of crystalline formations (memory effect).

After long-term storage, NiCd and NiMH batteries must be prepared before use, by slowly charging them, and following several discharge / charge cycles. Depending on the duration and temperature of storage, it may take from two to five such cycles to restore the full capacity of the batteries. And in the case of storage at a higher temperature, more cycles will be required. Several cycles may be required after, for example, two months of storage.

Li-ion and Li-pol batteries should be stored in a charged state. If a Li-ion battery is stored with a voltage lower than 2. 5 V for a period of three months or more, an irreparable loss of its capacity occurs. In addition, corrosion of elements may occur. Some Li-ion batteries do not allow recharging if the voltage at the terminals of the cell drops below a critical level. This requirement is made for safety reasons, because a deeply discharged cell has a chemical structure that changes and charging can be dangerous. The best results will be at storage Li-ion batteries, charged to the value of their capacity from 70 to 90%. Some manufacturers may recommend lower capacity values ​​during storage.

Typical errors when storing batteries.

The most common mistake made by owners of mobile equipment: laptop, tablet, smartphone, PDA, mobile phone, camera, camera, camcorder, MP3 player, radio station, radiotelephone, game console, e-book, netbook, WiFi router, navigator and other devices , is that they leave the mobile equipment or a spare battery (battery, battery, charging) in the car in hot summer or cold in winter. In summer, the temperature inside the car may exceed 60 ° C. It should be noted that high temperature is usually harmful to the operation of all types of batteries, regardless of their electrochemical system. Prolonged storage and operation of the battery at high temperatures accelerates the degradation of active materials inside the battery. It is curious to refer to the data of manufacturers of elements for batteries. The specifications for household items are the following figures (they are typical for all manufacturers):

NiMH batteries:

Standard charge: 0 ° C ... + 45 ° C.
Fast charge: 0 ° C ... + 40 ° C (for some manufacturers, 5 ° C ... + 45 ° C).
Discharge: -10 ° C ... + 65 ° C (for some manufacturers -20 ° C ... + 60 ° C).
Storage: -20 ° C ... 35 ° C (for 1 year)
Storage: -20 ° C ... 45 ° C (within 180 days)
Storage: -20 ° C ... 55 ° C (within 30 days)
Storage: -20 ° C ... 65 ° C (within 7 days)

Li-ion and Li-pol batteries:

Charge: 0 ° C ... + 40 ° C (for some manufacturers, 5 ° C ... + 45 ° C).
Discharge: -10 ° C ... + 60 ° C (for some manufacturers -20 ° C ... + 60 ° C).
Storage: -20 ° C ... 35 ° C (for 1 year), with some manufacturers -20 ° C ... + 25 ° C
Storage: -20 ° C ... 55 ° C (within 90 days), with some manufacturers -20 ° C ... + 45 ° C
Storage: -20 ° C ... 60 ° C (within 30 days)

In addition, I will give an interesting sign for a high-quality Li-ion battery with 100% initial capacity before storage:

Thus, the higher the temperature, the less time the battery should be in these conditions. Nickel-metal hydride batteries are most sensitive to high temperatures compared with batteries from other electrochemical systems. So continuous use and storage at 45 ° C will reduce the number of NiMH battery cycles by about 60 percent. NiCd elements, on the contrary, are less sensitive to high temperatures. Li-ion behave much like NiCd. And lithium-ion polymer elements, which are mainly of the same nature as Li-ion, can sometimes swell, especially at higher temperatures.

At low temperatures, the storage conditions are the best, but we note that it is for storage, because energy return at subzero temperatures for any battery drops, and it’s impossible to charge at all.

In addition to temperature, the degree of its charge has a significant effect on battery life. As research results show the best option is to charge the battery before storing it in half.