| Founded | 1994 |
|---|---|
| Closed | 2019 |
| Country | USA |
| Sector | Cleantech |
| Collapse type | Zombie Startup |
Sion Power
"25 years and $300M couldn't bridge the lab-to-factory gap for lithium-sulfur batteries."
Technically alive but effectively dead, burning cash
Key Events Timeline
Sion Power, a Tucson-based advanced battery startup backed by BASF with over $300M invested over 25 years, developed lithium-sulfur batteries promising 500Wh/kg energy density — double conventional Li-ion.
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