Causes of colloidal battery swelling

In many outdoor edge base stations, a large number of gel batteries have begun to be used as the basic guarantee power source.　　 In recent years, with the expansion of user communication demands and the improvement of service levels, mobile communication networks have rapidly extended to the countryside. Since this type of base station is completely exposed to the field, it has been found in the maintenance practice that under the high temperature environment in the south, the shell bulging phenomenon of the gel battery will have a greater impact on the battery life and the reliability of the communication power supply. Analysis of the cause of the swelling of the colloidal battery The electrolyte of the colloidal battery is gelled between the positive and negative plates of the battery pole group and the separator, so that the electrolyte does not flow, and has high cycle reliability and high charging efficiency in a high temperature environment. It has the advantages of long service life, and also has significant advantages in energy saving and pollution reduction. In the maintenance practice, it was found that after the gel battery was installed and used for about half a year, the swelling of the individual gel battery shell was very serious: the side wall and the cover of the battery had different degrees of swelling; the leakage of the safety valve was very obvious, and the battery cover The distribution of acid traces is basically 'sprayed' with the safety valve as the center; battery leakage causes the battery compartment body to be rusted; the safety valve port is cracked.　　From the analysis of maintenance records and on-site conditions, the main reasons for this phenomenon are as follows: 　　 One, the safety valve is not exhausted smoothly. The safety valve has the function of adjusting the air pressure inside the battery, and should be able to release the internal gas in time under normal circumstances. In the initial stage of use of a gel battery, since the electrolyte inside the battery is relatively 'richIf there is a problem with the safety valve and the exhaust is not smooth, when the amount of gas released during the charging process of the battery is large to a certain extent, the housing will swell due to 'flatulence　　 2. The battery management program chip parameter design of the switching power supply system is inconsistent with the use characteristics of the gel battery. By comparing the switching power supply parameter settings of the bulging battery site and the switching power supply parameter setting of the non-blowing battery site, it is found that the switching power supply manufacturer at the battery bulging site has designed a continuous current equalization function in order to fully charge the battery (that is, use a small current after charging is completed) Continue to charge the battery). When the equalizing current of the battery drops to the conversion condition of 10mA/Ah, the equalizing charge fails to switch to the floating charge program, and freewheeling equalization is required (the current of equalizing during the freewheeling phase in a high temperature environment may still be The rebound rises, and the freewheeling equalization time is generally 4 to 10 hours). In addition, the outdoor base station has poor power supply conditions and frequent power outages, which will inevitably cause the switching power supply to overcharge the battery every time it is charged. It also accelerates the corrosion rate of the battery electrodes and the battery's loss of water. The extremely high temperature inside the battery causes the battery to swell.　　 3. The temperature sensing line of the colloidal battery compartment is not connected, causing the system to fail to switch from equal charge to floating charge when the temperature reaches 40°C. In a high temperature environment, the failure of the temperature compensation function actually increases the total float voltage of the battery pack, which directly causes the final charging current of the battery to not be reduced, but it will increase the charging current by multiples and continue to affect the internal analysis of the battery. Gas and heat, thereby intensifying the electrolysis of the colloidal electrolyte water, causing the battery to swell.　　 Fourth, the battery ventilation conditions are poor. The design of the battery cabinet fully considers the anti-theft safety, resulting in poor ventilation and natural heat dissipation of the battery pack, and the temperature generated by the battery pack during the charging process cannot be diffused in time, which also has a certain impact on the swelling of the battery shell.　　Look at the solution together next time.