Overview
A supercapacitor stores charge directly at the electrode–electrolyte boundary in an electric double layer, so the whole physics of the device reduces to one number: how many square metres of surface are hidden in each gram of electrode. For half a century the industry has ground carbon ever finer and activated it with alkali or steam, reaching 1,500–2,000 m²/g with activated carbon from coconut shells and apricot, cherry, and peach stones. Fine-milled graphite has a physical ceiling: a particle of any size is a three-dimensional lump whose surface-to-volume ratio follows the sphere formula, so carbon remains locked inside while only the outer layer works. Porosity partly compensates, but a significant part of the area sits in micropores below 2 nm that ions enter slowly, so at fast rates 30–40% of the surface simply does not respond — precisely in the regimes where power is needed. Graphene has no such problem: it is a single-atom-thick carbon layer with no "inside", every atom lies on the surface, and both sides of the sheet work.
EXTRACAPACITOR is the construction the world industry has watched from the sidelines for twenty years — a supercapacitor with no metal substrate — made possible because Arbok produces its proprietary engineered-carbon material at roughly $50/kg instead of the $10,000–15,000/kg market price for industrial-purity graphene-like powders.
Applications
Warehouses with electric forklifts; city electric buses; highway DC fast-charging stations; hybrid buffer in electric vehicles alongside a lithium pack. Adjacent markets: forklifts, trams, lifts, truck starters, base-station buffers, data-centre backup power, cold climate down to −40 °C where lithium fails, military, space, and island power systems.
Operating Principle
In a classical device aluminium foil serves as the current collector and carries a layer of activated carbon; the aluminium accounts for 30–40% of the product mass and plays no part in charge storage — it is needed only because carbon conducts poorly. Arbok's proprietary engineered-carbon material conducts current itself, with specific conductivity exceeding copper, so EXTRACAPACITOR contains no aluminium. The material is pressed into thin sheets that act simultaneously as electrode and current collector; a solid ionic separator sits between two such sheets; the assembly is wound into a roll and packed into a housing. Every gram of the construction works to store energy. The design is only possible because the raw material is both pure enough and cheap enough — it cannot be done with activated carbon, and it cannot be done with market-priced graphene, but it can be done with Arbok's material at its in-house cost.
System effect: EXTRACAPACITOR does not replace a battery; it does what a battery cannot. A battery stores energy, a supercapacitor handles power. Placed as a buffer ahead of a battery, it lets a 150 kW grid connection deliver the 400–500 kW peak a car needs for fast charging, cutting charge time from 25–30 minutes to 7–10 and moving the stress of high current off the battery and onto the supercapacitor.
Key Parameters
Engineered-carbon electrode:
| Parameter | Value |
|—|—|
| Theoretical specific surface | 2,630 m²/g |
| Practical specific surface (folds, sheet restacking) | 1,800–2,400 m²/g |
| Specific capacitance | 180–250 F/g (vs 80–120 F/g for activated carbon) |
| Peak power | 3–5× higher than the carbon analogue |
| Electrical conductivity | Exceeds copper on a specific basis |
| Chemical inertness | Higher; fewer parasitic reactions with electrolyte |
EXTRACAPACITOR versus a classical supercapacitor:
| Parameter | EXTRACAPACITOR | Classical |
|—|—|—|
| Mass | −30–40% | — |
| Volume | −25–35% | — |
| Specific capacitance | 180–250 F/g | 80–120 F/g |
| Specific energy | 30–40 Wh/kg | 10–15 Wh/kg |
| Self-discharge | 5–8% per day | 20–25% per day |
| Cycle life | 500,000 cycles | 100,000–300,000 cycles |
| Batch consistency | ±1–2% | ±10–15% |
Arbok's engineered-carbon material versus the market:
| Indicator | Arbok | Market leaders |
|—|—|—|
| Purity | 99.98% | 92–97% |
| Price | $50/kg | $10,000–15,000/kg |
| Output | Up to 1,000 kg/h | 50–100 kg/month |
| Installation | Autonomous, gas/diesel | Requires tens of MW grid supply |
One installation running 20 hours a day produces 20 tonnes, or 7,200 tonnes a year. Total world graphene output from all producers in 2023 was estimated at 3,500–4,000 tonnes, so one Arbok line delivers twice the entire global industry.
Architecture and Components
Arbok's proprietary engineered-carbon material is pressed into thin sheets acting simultaneously as electrode and current collector; a solid ionic separator between two sheets; the stack wound into a roll and packed into a housing. No aluminium foil and no metal substrate. Modules connect in series and parallel without matching, balancing, or sorting on the assembly line, thanks to ±1–2% batch consistency.
Advantages
30–40% lower mass and 25–35% lower volume than a classical supercapacitor. Specific capacitance of 180–250 F/g and specific energy of 30–40 Wh/kg against 80–120 F/g and 10–15 Wh/kg. Self-discharge of 5–8% per day against 20–25%. Cycle life of 500,000 against 100,000–300,000. Batch consistency of ±1–2% against ±10–15%, so modules need no matching, balancing, or sorting. Fast charging no longer degrades the battery, because the supercapacitor absorbs the current stress. Raw-material independence: Arbok manufactures its engineered-carbon material in-house through a proprietary route — fast, clean, scalable — at 99.98% purity and roughly $50/kg, a combination of "industrial volume + high purity + affordable price" that no competitor occupies.
Integrations
Lithium battery packs (as a power buffer ahead of the battery); DC fast-charging infrastructure; Arbok's own engineered-carbon production lines.
Deployment & Operation
Deployed as a buffer module ahead of a battery or grid connection. Natural testing is under way: −40 °C cold, +60 °C heat, automotive vibration, accelerated degradation over thousands of cycles — approximately 18–24 months of work remaining.
TRL
The technology sits at an early-series stage: core electrode and cell performance is established and reproducible in production batches, while full qualification for automotive and industrial duty is still being built out. Natural testing (cold, heat, vibration, accelerated degradation) is in progress with roughly 18–24 months of work remaining before the platform is ready for full-scale qualification and broad commercial release.
Market Potential
Direct supercapacitor market in 2024: about $4 billion; forecast for 2030: $12–15 billion. A 10% share for EXTRACAPACITOR would mean $1.2–1.5 billion in annual sales. The adjacent market is larger — forklifts, trams, lifts, truck starters, base-station buffers, data-centre backup, cold climates below −40 °C where lithium fails, military, space, and island power systems — giving a total addressable market of $60–80 billion by the end of the decade.
Typical Project Economics
Engineered-carbon material production cost: $15/kg. Finished EXTRACAPACITOR module price: $80–120/kg. The margin in this range is secured because Arbok produces the raw material itself at its own cost; no competitor has this scheme.
Warehouse with electric forklifts: a lithium battery costs $10,000–12,000, lasts 3–5 years, and is replaced 3–4 times over the 15-year life of the machine — $30,000–48,000 per machine. A comparable EXTRACAPACITOR block costs $14,000–16,000 and works all 15 years without replacement, saving $15,000–30,000 per unit. A fleet of 50 forklifts frees $0.75–1.5 million.
City bus: an electric bus currently spends 4 hours on overnight charging. With a 10 kWh EXTRACAPACITOR buffer it tops up in 3 minutes at the terminus, raising useful working time from 14–16 hours per day to 20. A fleet of 300 buses delivers the productivity of 375–400 vehicles without buying new equipment.
Highway fast-charging station: a 150 kW DC charger serves one car in 20–30 minutes. A station with a 200 kWh EXTRACAPACITOR buffer delivers a 500 kW peak into the car, charging it in 7–10 minutes and tripling station throughput on the same grid connection.
Hybrid in an electric vehicle: a 150 km lithium pack plus a 50 km EXTRACAPACITOR buffer. Fast charging goes into the buffer (5 minutes to full) and the lithium is topped up from the buffer in the background under gentle conditions. Lithium lasts 2–3× longer, battery warranty rises from 8 to 15 years, and the manufacturer saves $5,000–8,000 on a smaller lithium pack.
Risk Factors
Part of the current EXTRACAPACITOR data is calculated and early-series rather than measured in mass production. Natural testing — −40 °C cold, +60 °C heat, automotive vibration, accelerated degradation over thousands of cycles — is still in progress, with approximately 18–24 months of work remaining.
Related Technologies
Engineered-Carbon Materials Platform · Modified Glassy Carbon (GCM) · LONG BATTERY