15 Steps from Lead to Sealed Battery

VRLA battery manufacturing transforms lead and glass-fiber separators into sealed, maintenance-free energy storage. From grid casting and paste mixing to AGM wrapping, electrolyte filling and valve-regulated formation, every stage is engineered for precision and repeatability, so every battery leaves the line with dependable standby power and long service life for UPS, solar, telecom and industrial applications.

Quality is built in at each step, not inspected in at the end. Our China factory combines automated production equipment with strict process controls, delivering sealed VRLA batteries that meet the demands of OEM manufacturers and system integrators alike.

01

LEAD AS A RAW MATERIAL

Lead in 45 kg bars is the most important raw material for VRLA batteries. The delivered lead is processed into positive and negative plates.

02

PRODUCTION OF LEAD OXIDE

A ball mill comminutes the lead into a fine powder to create the largest possible surface for oxidation.

03

PRODUCTION OF LEAD OXIDE IN THE BARTON REACTOR

Very fine lead droplets and air are used to create lead oxide, which is then stored in oxide silos.

04

GRID CASTING

VRLA grids are cast from lead-calcium alloys, ensuring low self-discharge and dimensional precision for long, consistent service life.

05

PASTE MIXING

Positive and negative lead pastes are mixed separately with different formulations, with density and consistency controlled for optimum electrochemical performance.

06

PASTING AND CURING

The pastes are applied to the grids by automatic pasting machines. The pasted plates are then cured under controlled temperature and humidity to build the active material structure.

07

PLATE FORMATION

Cured plates are electrochemically formed to convert the paste into active material with the required capacity and voltage characteristics.

08

PLATE DRYING

Formed plates are thoroughly dried. Precise moisture control is critical for VRLA batteries, because the electrolyte volume is limited by design.

09

AGM SEPARATOR WRAPPING

Dried plates are wrapped with microporous glass-fiber separators that absorb and hold the electrolyte. This AGM design enables internal oxygen recombination and a truly sealed, maintenance-free battery.

10

GROUP STACKING AND BURNING

Wrapped positive and negative plates are stacked alternately into plate groups, and the lugs are welded to cast-on straps to connect the cells.

11

CONTAINER INSERTION AND SEALING

Plate groups are inserted into the battery container, and the cover is heat-sealed to the container for a tight, leak-proof enclosure.

12

ELECTROLYTE FILLING

A precisely measured amount of electrolyte is filled under vacuum so that the AGM separators are fully saturated. The starved electrolyte design makes the battery spill-proof and position-independent.

13

VALVE-REGULATED FORMATION

Assembled batteries are charged in a controlled formation process. Oxygen generated at the positive plates recombines at the negative plates inside the cell - the principle behind valve-regulated, sealed operation.

14

VALVE INSTALLATION AND TESTING

Pressure-relief valves are installed to regulate internal gas pressure. Every battery then undergoes leakage, capacity, open-circuit voltage and load testing before dispatch.

15

PACKAGING AND DELIVERY

Tested batteries are labeled, coded, packed and dispatched to OEM customers, distributors and system integrators worldwide.

From raw lead to a sealed, fully tested VRLA battery, all 15 steps serve one goal - reliable standby power you can count on. Explore our storage battery range to see the result: FM and GFM series, 2V long-life, 12V front terminal, OPzV and OPzS batteries, each engineered for dependable backup power.