It's a pretty big claim, 280kWh/m^2. That's 4x the density of proposed iron-air batteries at utility scale (100h storage x 3MW/acre = 74kWh/m^2). However, I don't know if areal energy density is relevant to the market.
For bulk grid storage, batteries will likely be buried and not very dense.
For local spot backup for buildings and urban areas you absolutely want the highest power per cubic unit.
Hyundai Ioniq-5 and other vehicles can utilize the increasingly common 350 kW connectors — including the Lucid Air, the Porsche Taycan, the Audi E-Tron GT, and the GMC Hummer EV. [0]
This enables them to deploy the fastest DC charging in places where the grid cannot support it. It’s a big deal.
[0] https://www.greencarreports.com/news/1135771_hyundai-ioniq-5...
It might also be designed to support multiple EV’s as most cars can only stay at 350kW for a relatively short period.
ESS == stationary Battery Energy Storage System. So this would be comparable to Tesal's Megapack business unit. I mean 790kW in an EV? That's must be for a rocket.