Just under 3,000 LBS for the battery is quite a lot but at least it gets enough estimated range.
The Hummer pack (and likely the Silverado packs) will likely be a lot heavier per kWh than what most of the other Ultium-based EV packs for other upcoming GM EV's. (Lyriq, Equinox, etc.). Since the BT1 platform does not use a conventional frame-and-rail structural concept, but an "integrated body-frame-pack" structural concept, the BT1-based Ultium pack structure itself has to be extremely strong. It is the key element to provide extreme torsional stiffness to keep everything together while towing, bouldering, etc. This means the outer frame and crossmembers carrying the modules will be super-strong and have rigid attachments, and likely be heavier than required for BEV3-platform passenger EVs. Also, transmitting almost 2,000 total amps to those three 259-kW motors means massive bus-bars, main contactors, etc, also adding weight. That said, the modules themselves will likely be very similar or identical to Lyriq's . And for recycling, the unique issue is recycling the cells within the modules. Everything else - bus-bars, module cases, pack frames, etc. are either stamped steel or aluminum and recyclable through conventional means.