theion

A new kind of battery. Built around sulfur.

Why now: Lithium-ion is reaching its practical ceiling. Just as electrification needs lighter, cleaner storage.

• Sodium-ion: 160 Wh/kg (State-of-the-art)
• LFP: 220 Wh/kg (State-of-the-art)
• NMC: 330 Wh/kg (State-of-the-art)
• Solid state: 450 Wh/kg (State-of-the-art)
• Today's practical ceiling: 450 Wh/kg

Why us: 500 Wh/kg redraws the map. Our crystalline sulfur cathode targets 1,000 Wh/kg at 1,000 cycles.

• theion: 500 Wh/kg (theion next milestone)
• theion target: 1,000 Wh/kg (theion target)

Why sulfur: Abundant, low-cost, sustainable. 5 million tonnes of the 85 million tonnes of sulfur produced each year could satisfy total battery demand.

• Produced each year (industrial by-product): 85 Mt
• Enough for every battery (total battery demand): 5 Mt

The next step in electrification will not come from another bigger pack. It will come from a better chemistry.

Lithium Anode

Pre-lithiated host structure

Electrolyte

Semi-solid state

Sulfur Cathode

Monoclinic crystalline and conductive coating

Pouch

Cell housing

Our vision

We are developing a cell to outperform today's best battery technologies.

• 3× the energy per kilogram, vs. today's lithium-ion cells
• ¹/₃ the material cost, per cell
• ¹/₃ the CO₂ in production, per kWh

All figures are targets for our cell.

Areas of usage

Electric vehicles (Mobility)

4× the range at equal battery mass. Driving range: Lithium-sulfur 2,532 km, NMC 633 km. Assumptions: 2,000 kg EV, 100 kWh pack, 250 Wh/kg baseline vs. 1,000 Wh/kg theion cells, 15.8 kWh/100 km. Cell weight drops from 400 kg to 100 kg, or range rises from 633 km to 2,532 km at constant battery mass.

Satellites (Space)

–75% cell mass at equal energy. Energy density: Lithium-sulfur 1,000 Wh/kg, NMC 250 Wh/kg. Assumptions: 250 Wh/kg lithium-ion baseline vs. 1,000 Wh/kg theion cells at equal stored energy.

Power tools (Tools)

4× the runtime in the same pack. Energy density: Lithium-sulfur 1,000 Wh/kg, NMC 250 Wh/kg. Assumptions: 250 Wh/kg lithium-ion baseline vs. 1,000 Wh/kg theion cells in a pack of equal mass.

Humanoid robots (Robotics)

12 h of useful work on one charge. Uptime: Lithium-sulfur 12 h, NMC 3 h. Assumptions: 75 kg humanoid robot, 8 kg payload, 1 kWh battery, 250 Wh/kg baseline vs. 1,000 Wh/kg theion cells, 330 Wh/h consumption. Cell weight drops from 4 kg to 1 kg, or operating time rises from 3.0 h to 12.1 h at 4 kWh.

Drone delivery (Logistics)

1.8× payload-based revenue. Flight distance: Lithium-sulfur 30 km, NMC 25 km, LFP 18 km. Assumptions: Delivery drone at equal pack mass, LFP and NMC baselines vs. 1,000 Wh/kg theion cells; cost per mission and payload revenue scale with range and payload.

eVTOL (Urban air)

2.8 h aloft instead of 0.8 h. Flight time: Lithium-sulfur 2.8 h, NMC 0.8 h. Assumptions: Four-seat eVTOL, 1,950 kg empty weight, 453 kg payload, 125 kWh pack, 300 Wh/kg baseline vs. 1,000 Wh/kg theion cells, 150 kWh/h consumption. Cell weight drops from 417 kg to 125 kg, or flight time rises from 0.83 h to 2.78 h.

Vision

For decades, battery-powered machines have been designed around energy scarcity. The result is not a lack of ambition. It is a chemistry limit.

Weight · Energy · Charge time · Cost.

theion tackles that limit at the battery level, with a lithium-sulfur architecture built around a crystalline sulfur wafer. This is not meant to stay in the lab: the battery is engineered in Berlin with manufacturability in mind, so partners can bring it into existing production environments.

Made in Berlin. Powering the world.

Own production

For high-value markets where performance matters more than pure volume.

Partnerships

For selected applications.

Licensing

To scale the technology globally through manufacturers that already operate at industrial volume.

Power. Unbound.

Sulfur crystal batteries · engineered in Berlin.

Follow our path

Get major technical and company milestones.

Partner with us

For industrial customers, investors, and policy partners

Careers

Open roles in engineering, science, and operations, based in Berlin

Three functional layers. One cell architecture

The theion Crystal Battery stack eliminates the performance trade-offs of conventional lithium–ion. Each layer plays a precise role in delivering up to 3× more energy density at 1/3 the material cost.

Lithium Anode: Pre-lithiated host structure

Proprietary lithium metal host anode reduces weight, enables fast charging and avoids dendrites. Patented safe anode design

Electrolyte: Semi-solid state

Proprietary gel polymer electrolyte operating within the sulfur wafer voids. Enables intrinsically safe operation

Sulfur Cathode: Monoclinic crystalline and conductive coating

Grown directly on top of highly conductive CNTs from molten sulfur via theion's Direct Crystal Imprinting (DCi), with no undefined slurry

Our battery aims to outperform the state of the art across disciplines

Battery cell targets based on theion's patent portfolio.

• Gravimetric energy density: 1,000 Wh/kg, Li-ion ~330 Wh/kg (3× Li-ion)
• Volumetric energy density: 1,000 Wh/l, today's cells ~500 Wh/l (2× today)
• Production CO₂: 18 kgCO₂/kWh, NMC ~54 kgCO₂/kWh (¹/₃ of NMC)
• Peak power: 12,000 W/kg (Ultra-fast charge)
• Cycle life: 1,000+ cycles (Target)

Engineered in Berlin

Cells designed, built, and tested in theion's Berlin facility.

Measurement and testing · Precision winding · Battery cell testing · Berlin facility · Crystal growth reactor · Measurement station · Dry room equipment · Cell assembly · Sulfur melt, lab scale · Berlin headquarters.

From lab to scale

From our first pouch cell developed in Berlin towards industrialization and mass production. By 2029 we target to manufacture cells with 1000 Wh/kg and 500 cycles in our 50 MWh pilot line.

2026 (Next milestone) · Pouch cell multi layer

500 Wh/kg, 50 cycles, >2 Ah. First single-layer pouch cells in Berlin. BMFTR project awarded.

2027 · Pouch cell multi layer

500 Wh/kg, 500 cycles, 5 Ah. Stacked multi-layer cells with ten times the cycle life.

2028 · Pilot line setup

500 Wh/kg, 500 cycles, 20+ Ah. Automotive-format cells while the pilot line is equipped.

2029 · Pilot line SOP

1000 Wh/kg, 500 cycles, 50+ Ah. Start of production on the 50 MWh pilot line.

Want to learn more? Let's talk.

Supervisory board

• Dr. Gerhard Cromme, Chairman. Chaired the supervisory boards of Siemens and thyssenkrupp; chaired the German Corporate Governance Code commission. Chairman at Aroundtown, AUTO1 and Target Global.
• Lukasz Gadowski, Vice Chairman. Vice Chairman since March 2021. Founder and CEO of Team Global, co-founder and Chairman of Delivery Hero, Vice Chair at Enpal, Chairman at MILES Mobility.
• Stine Rolstad Brenna, Board member. Board member since August 2022. Former CFO of Hafslund (E-CO); Chair of Rabbalshede Kraft, deputy chair and chair of the audit committee at Lyse (utility and telecom), director at Arendals Fossekompani (industrial investments), director and chair of the audit committee at Bohus, chair of LKP (pension fund), chair of FEC (energy management) and director at Heimdall Power (grid line rating).
• Osman Dumbuya, Board member. Founder and CEO of Incari. Strategic Advisor at Team Global; previously Managing Director of CGI Studio. Diploma in Computer Science, TFH Berlin.
• Henning Rath, Board member. Board member since September 2023. CEO of EnerVenue; board member at Enpal, formerly its Managing Director and Chief Supply Chain Officer. Young Global Leader, World Economic Forum.
• Sven Wiszniewski, Board member. Board member since February 2025. Venture and growth capital investments at Oetker Collection; investor and board observer at R3 Robotics and Hadrian, board director at Win-Win.

Team Global · Enpal · SPRIN-D · Oetker Collection · Hub71 · BMFTR.

“theion is in the vanguard of this tech revolution.” Lukasz Gadowski, Lead Investor · CEO, Team Global.

Join the team. Explore our open roles and help shape the future of batteries.

Open positions

All roles are based at our Berlin facility. Select a role to read the full description and apply on our hiring portal.

• Unsolicited Application · Berlin · Full-time · Permanent

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