Who makes grid-scale BESS for AI data centers

Grid-scale batteries at a campus are a different animal from the batteries inside a UPS. The UPS bridges seconds to minutes and exists to protect the load; a battery energy storage system sits on the utility side of the problem and exists to change the site's relationship with the grid — shaving demand peaks, smoothing a load profile the utility is uncomfortable with, storing contracted renewable output, or in some interconnection agreements standing in for capacity the grid cannot yet deliver. That last use is what has made this part matter to AI specifically. Interconnection queues are long, and a campus that can demonstrate it will not draw its full load at system peak has a materially easier negotiation than one that cannot. Storage becomes a way to buy a connection date, which is a different justification from energy arbitrage and tends to survive changes in power prices. The suppliers here split into cell makers, system integrators who buy cells and sell installed capacity, and developers who own and operate the asset next to the campus. Those are three different businesses that all appear on this part. What to look for is which of the three a company actually is, how the asset is contracted — owned by the operator, by the utility, or by a third party selling a service — and the augmentation plan, since a storage system loses capacity over its life and the contract has to say who pays to restore it.