Who makes VRLA for AI data centers

Valve-regulated lead-acid is the battery the industry is moving away from and still has an enormous installed base of. It is cheap, thoroughly understood, and supported by a mature recycling chain — genuine advantages that get lost in the comparison with lithium. The disadvantages are the ones that decide new builds: much lower energy density, so the battery room is large, and a service life measured in a handful of years, so it is replaced repeatedly over a facility's life. The replacement cycle is the part operators underestimate. A VRLA string degrades gradually and can fail to deliver its rated runtime long before it fails outright, which is why capacity testing rather than voltage monitoring is what actually tells you whether the UPS will hold. Cells also fail individually inside a string, and a single weak cell limits the whole string. Where it still gets specified is retrofit and cost-driven builds — replacing strings in an existing room is far cheaper than converting that room for lithium, and the code and insurance path is already established. AI-scale new build has largely gone the other way. What to look for is whether a site is running VRLA by choice or by inheritance, the age and test history of the strings, and whether the room's ventilation and spill containment are still appropriate for the chemistry actually installed.