Many people buy lfp battery packs and do not know how to install and maintain them. There are many places to pay attention to when using lithium batteries, because everything needs to be maintained, so as to prolong the service life of lithium batteries.
Precautions for installation of lfp battery pack
The open circuit voltage must be measured before the lfp battery pack is installed. The open circuit voltage difference cannot be greater than 50mV. The battery test should be done and recorded.
Although the lfp battery pack is shipped from the factory, the positive and negative plates have been activated by charging and discharging. If the installation date of the lfp battery pack is far from the date of delivery, the capacity of the lfp battery pack will inevitably be lost after long-term self-discharge. In addition, the lfp battery pack is generally about 60% charged when leaving the factory. Therefore, the lithium battery pack should be supplemented at the beginning of installation. In addition, due to the difference in the self-discharge of the single cells, the terminal voltage of each cell may be unbalanced.
Before installing a new lfp battery pack, the open circuit voltage must be measured, and battery test records must be made. The capacity test can be performed on the battery pack at the hour rate of 0.1C10(A) and 0.2C5(A) with a dummy load. This test also does not need to be connected to the battery management system, just connect the battery packs in series, but the discharge process During the test, the battery cell voltage must be strictly tested.
During the test, the total voltage, discharge current, and cell voltage of the battery should be measured and recorded every hour. Only when the terminal voltage of the battery reaches 2.5V, stop discharging immediately, and calculate whether the actual battery discharge capacity is basically consistent with the rated capacity of the battery.
If the discharge capacity of the battery pack is too different from the rated capacity (greater than 15%) when the discharge reaches the termination voltage, it means that there may be a problem with the factory capacity of the lithium battery pack, and you should contact the relevant manufacturer to deal with it in time.
Maintenance of lfp battery pack
(1) Operating environment requirements for lfp battery packs
Requirements for the operating environment of the lfp battery pack: According to the environmental requirements of the battery, the room temperature should not exceed 55°C, and it is recommended that the ambient temperature should be kept between 0°C and 55°C. Avoid direct sunlight on the battery, and the sun-facing windows should be shaded. Make sure to leave enough maintenance space between the lithium battery packs.
(2) Precautions for the use of lfp batteries
Lfp battery packs of different specifications and models are prohibited from being used in the same DC power supply system, and batteries with different degrees of old and new should not be mixed in the same DC power supply system.
If there is a power and environment centralized monitoring system, the total voltage, current, single module voltage, temperature, and capacity of the battery pack should be monitored in real time through the dynamic environment centralized monitoring system and BMS. At the same time, the battery monitoring device is used to understand the battery charge-discharge curve and performance, conduct actual measurements regularly, and deal with faults in time.
(3) Items frequently inspected for lfp batteries
Always check whether the poles and connecting strips of the lfp battery are loose. Whether there is damage, deformation or corrosion. Whether the connection is loose, whether the battery case is damaged, leaking or deformed, and whether the temperature rise of the battery and the connection is abnormal.
According to the technical parameters and on-site environmental conditions provided by the manufacturer, check whether the voltage of the battery pack and the single module meets the requirements, and check whether the charging current of the battery pack during intermittent floating charging is within the required range. Check whether the charging current limit value of the battery pack is set correctly. Check whether the low-voltage alarm and high-voltage alarm settings of the battery pack are correct.
(4) Voltage requirements for equalizing and floating operation of lfp batteries
The intermittent charging voltage of lfp battery pack is generally set to the single battery: 3.60 ~ 3.76V, and the high-voltage DC output voltage is 278V. Measure the voltage of the battery pack and the terminal voltage of the single cell every month and compare it with the battery monitoring display, and solve the problem in time.
What aspects should be paid attention to in the maintenance of lithium battery packs?
1. Charge according to the standard time and procedure, even for the first three times;
2. Lithium battery packs should be stored in a cool, dry and safe environment;
3. The activation of the lithium battery pack does not require any special method, and the lithium battery will be activated naturally in the normal use of the mobile phone. If you insist on using the popular “first three 12-hour long charge activation” method, it won’t actually work.
4. Avoid placing lithium batteries near heat sources, open flames, flammable and explosive gases, and liquids, which may cause battery leakage, heat, smoke, fire and explosion.
5. If the lithium battery needs to be stored for a long time (more than one month), it is recommended to charge it to 40%-60%, and the battery needs to be recharged for 1-2 hours every month during the storage time.
The above are the precautions for the installation and maintenance of lfp battery packs. In addition to the fact that manufacturers must recognize and prevent the safety risks that may be caused by the use of lithium batteries, the general consumer also has the responsibility to face the dangers of lithium batteries and understand how to be safe. Use, reduce the injury caused by the accident of the lithium battery pack.
The engineer team of the OEM manufacturer of Keheng lithium battery can provide technical solutions for installation and maintenance free of charge for all users. Welcome to leave a message in reviewl or quara for questions or email consultation.