Industry Knowledge

Maintenance-free lead-acid batteries are widely used in UPS, telecommunications, solar storage, security and medical equipment systems. Unlike batteries that need regular topping up, maintenance free means no topping up and no water addition, so the focus of routine inspection shifts from electrolyte level maintenance to checks of appearance, mounting condition and the operating environment. Understanding what maintenance free, leak resistant and low self-discharge mean in practice helps buyers and engineers judge whether a battery is still serviceable and when replacement should be arranged.

Routine checks can start from appearance and installation. The sealed construction and the absence of free electrolyte mean that no electrolyte leakage occurs in normal use, so during inspection look for any abnormal marks on the case or around the terminals. On mounting direction, this type of battery supports vertical and horizontal mounting but must not be used inverted, and confirming that the on-site mounting position respects this limit is one of the check items. Carrying handles make installation easier and should be used when replacing or moving a battery, so that improper handling does not damage the case. Each cell integrates a flame arrestor and is fitted with an explosion-proof filter and flame arrester as safety features of the battery itself, and inspection need only confirm that the relevant parts are not obscured or altered.

Low self-discharge is another characteristic of this type of battery: the self-discharge rate is below 3% per month and capacity loss is under 3% per month. This means capacity falls slowly while the battery is in storage or standby, but it does not mean that periodic checking can be omitted. For UPS and telecommunications batteries on long-term float standby, record changes in condition using the monitoring already provided by the system; for batteries held in storage, the low self-discharge rate can serve as one reference for setting the inspection interval, while the actual interval should still follow the project's operating and maintenance procedure.

Replacement judgement should be based on inspection records rather than a single observation. Where appearance checks reveal an abnormal case or signs of leakage around the terminals, or where the mounting position and connection condition do not meet requirements and cannot be restored, the case should be included in a replacement assessment. For products that use absorptive glass mat technology for efficient gas recombination, or gelled electrolyte technology, the maintenance-free and free-acid-free characteristics likewise require the integrity of the sealed construction as a precondition for judgement. It should be noted that figures such as a float service life of up to 10 years come from the product description, and the actual replacement timing should be determined from the description of the specific model together with the on-site operating records.

For selection and replacement checks, confirm item by item against the application: uninterruptible power supplies, data centres, telecommunications facilities, security systems, access control, emergency lighting and video surveillance, medical equipment, alternative energy, grid and electric power applications, road lighting and traffic signals, and mowers, golf carts, e-bikes and scooters, wheelchairs and floor cleaning equipment. Different applications have different requirements on mounting direction and discharge regime; for example, models designed specifically for heavy-duty cycling or supporting high-rate discharge should be checked against the corresponding characteristics. B.B. Battery was founded in 1992 and operates a production base in the Changsha XingSha National Economic and Technological Development Zone, Hunan Province, commissioned in 2006, with about 60,000 square metres of plant, providing a basis of product information for battery selection in the applications above.