The Multi-Day Storage Gap
Why lithium-ion can't solve 24/7 carbon-free energy for AI infrastructure
Lithium-Ion (Tesla Megapack)
CO2 Battery (Energy Dome)
Lithium-IonTesla Megapack 3
⚠ The 8–100 Hour Gap
Wind and solar droughts can last 3–7 days. Lithium-ion maxes out at 8 hours. This gap is where iron-air and CO2 batteries compete — and where 24/7 carbon-free energy either works or doesn't.
Iron-Air Cost
<1/10×
vs lithium-ion per kWh
CO2 Battery Savings
30%
cheaper than lithium-ion
Google Minnesota
30 GWh
world's largest iron-air deployment
Li-Ion Efficiency
85–95%
round-trip (but 8h max)