Battery Industry Basics

CSB is a global leader in the manufacture of valve-regulated lead-acid batteries, with products sold in more than 100 countries and regions, and its VRLA product lines are all built on the same technical route. VRLA stands for Valve Regulated Lead Acid, i.e., valve-regulated sealed lead-acid battery. Although it still belongs to the lead-acid family, its mode of operation differs from that of older open batteries: during normal use the battery remains sealed, and the gas generated internally reaches the negative electrode via the absorbent glass mat (AGM) and completes recombination; only when pressure becomes abnormal does the safety valve open and release. This gives rise to features such as maintenance-free operation, rechargeability, and leakage resistance.

In VRLA-AGM, the key task of the AGM separator is to provide a path for oxygen: oxygen transfers from the positive electrode side to the negative electrode side and then recombines into water. According to official data, the recombination rate can reach up to 99%. Electrolyte loss is therefore significantly reduced, and the battery does not require water replenishment during its service life. Another design element is the pure lead grid and proprietary formulation: the grid both conducts current and supports the active material; the pure lead system helps slow corrosion, so float/standby life can be made longer. For this reason, standby power scenarios that require long-term online operation and low maintenance have widely adopted VRLA-AGM batteries.

The electrical specifications of VRLA-AGM are uniformly rated at 25°C (77°F). For a 12V battery, the equalization voltage is 14.4-15.0 Vdc, and the float voltage is 13.5-13.8 Vdc; different models and different cell constructions will cause the values to vary. For temperature conditions, the nominal value is 25°C: the discharge range is -15°C~50°C, and some series can be extended to -25°C~50°C; the charge and storage range is -15°C~40°C. Design life is stated under 25°C float/standby conditions, ranging from 5 years to 20 years, and some series have an additional Eurobat (20°C) classification. When selecting a model, capacity correction and service-life expectation judgments must refer to these specifications.

CSB currently has 142 models on sale, distributed across 20 series. Voltage specifications include 2V cells, 6V, 12V, and 512V lithium battery cabinets; capacity types cover 4.5Ah to 1700Ah, and power types cover 18W to 9000W (5–15 minute rate). VRLA-AGM product lines are further divided by application: data center UPS uses HR, HRL, XHRL, XPL, XHT, etc.; telecom scenarios correspond to MSJ, MSV, MU, TPL, XTV, etc.; renewable energy corresponds to RE, XTV-WT, etc.; general-purpose types are GP, GPL; and electric mobility includes EVX, EVH. Each series has different emphasis in terminal type, front terminal or top terminal, cycle life, and high-temperature tolerance.

Understanding the working mechanism of VRLA-AGM is practically helpful for daily use and maintenance. Gas recombination requires suitable charge voltage and temperature conditions: high temperature or overcharging accelerates water loss and grid corrosion, while undercharging causes sulfation, and both conditions shorten actual service life. Therefore, in project applications, the settings of charging equipment should refer to the equalization and float ranges given in the corresponding model documentation, and ambient temperature should be included in the evaluation of the design life specifications. CSB model documentation also lists referenced standards such as IEC 61056, IEC 60896, IEC 60254, IEC 61427, and UL1989 Recognized for technical cross-reference.