# Ionblox

> Ionblox is a Fremont, California battery company building high-energy, high-power lithium-ion cells around a proprietary pre-lithiated silicon (SiOx) anode. Spun out of the earlier Zenlabs Energy effort and rebranded in 2022, the company targets two demanding markets - electric vehicles and electric aviation (eVTOL) - with cells that it says exceed 330 Wh/kg and can charge to roughly 60% in five minutes while holding up past 1,000 cycles. Backed by eVTOL maker Lilium, Applied Ventures, Temasek and Catalus Capital, Ionblox has raised about $32M in Series B funding and holds more than 40 patents.

- **Founded:** 2017
- **Headquarters:** Fremont, California, United States
- **Founders:** Sujeet Kumar (Co-Founder & CEO), Herman Lopez (Co-Founder & VP of Product / CTO)
- **Team size:** Small (roughly 5-50 employees reported across sources; early-stage)
- **Products:** Pre-lithiated silicon (SiOx) anode cells, Electric aviation (Air) cells, Electric vehicle (Drive) cells
- **Notable:** Named one of America's Top GreenTech Companies of 2024 by TIME and Statista., Cells reported to exceed 330 Wh/kg using a pre-lithiated SiOx anode with high-nickel NMC cathode., Extreme fast charge: ~60% capacity in 5 minutes, ~80% in 10 minutes, over 1,000 cycles.

## Products & services

- **Pre-lithiated silicon (SiOx) anode cells** — Lithium-ion cells built around a proprietary pre-lithiated silicon-oxide anode paired with a high-nickel NMC cathode, engineered to exceed 330 Wh/kg while charging to ~60% in 5 minutes and ~80% in 10 minutes.
- **Electric aviation (Air) cells** — Large-format high-power cells developed for eVTOL and electric aircraft, including cells being qualified for the Lilium Jet, validated by third-party labs at high energy retention over hundreds of cycles.
- **Electric vehicle (Drive) cells** — Low-cost, extreme-fast-charge (XFC) silicon-based cells for passenger EVs, developed in part under United States Advanced Battery Consortium (USABC) contracts.

## Achievements

- Named one of America's Top GreenTech Companies of 2024 by TIME and Statista.
- Cells reported to exceed 330 Wh/kg using a pre-lithiated SiOx anode with high-nickel NMC cathode.
- Extreme fast charge: ~60% capacity in 5 minutes, ~80% in 10 minutes, over 1,000 cycles.
- Earned UN 38.3 certification for its high-performance silicon-dominant-anode cells (2023).
- Idaho National Laboratory validated 1,000 charge-discharge cycles from its silicon-anode cells.
- Third-party lab reported 88% energy retention after 800 full (100% DoD) cycles on Lilium-bound cells.
- Holds more than 40 issued patents, including for pre-lithiation of silicon-based anodes.
- Attracted eVTOL maker Lilium as both an investor and a customer.

## Latest updates

- **2024-03** — Named one of America's Top GreenTech Companies of 2024 by TIME Magazine and Statista.
- **2023-11** — Signed a joint development agreement with Gelion to advance battery technology toward global electrification.
- **2023-10** — Debuted lithium-silicon cells claiming breakthroughs in extreme fast charging and extended range.
- **2023-08** — Earned UN 38.3 certification for its silicon-dominant-anode cells.
- **2023-03** — Appointed battery scientist Dr. Shirley Meng to its advisory board.
- **2023-02** — Increased Series B to $32M with Lilium, Applied Ventures, Temasek and Catalus Capital.

## Links

- Website: https://www.ionblox.com
- LinkedIn: https://www.linkedin.com/company/ionblox/
- Twitter/X: https://twitter.com/ionblox_

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Profile page: https://yespress.io/ionblox
Published by YesPress — https://yespress.io
Last updated: 2026-07-11