Feasibility Study

Battery Passport
on Cardano

Lambda Sistemi · 2026

The EU Battery Regulation

Regulation (EU) 2023/1542 — first product passport ever mandated

Feb 2027
Mandatory deadline
4–5M
Batteries / year in EU
Item-level
Each battery gets its own passport

Art. 77(1): "each LMT battery, each industrial battery >2 kWh and each EV battery shall have an electronic record"

Five regulations converge on batteries

Raw Materials

CRMA 2024/1252

16%

Recycled cobalt 2031

Carbon

Battery Reg Art. 7

A–E

Class per site

Second Life

Art. 77(2)

SoH

History per battery

Consumer

Empowering Dir.

Verified

No greenwashing

Recycling

Battery Ch. VIII

Chem ID

Hazardous, disassembly

The unsolved problem

Article 14

BMS must contain
SoH data

?

Article 77

Passport must have
SoH data

The bridge is undefined

The regulation creates two obligations and leaves the data path between them completely unspecified. Battery Pass consortium, CEPS, and Seraph all flag this as the biggest unsolved challenge before Feb 2027.

Connected EVs: maybe telematics. E-bikes, forklifts, UPS: no internet, no path.

Who is responsible?

Manufacturer Creates passport OEM / Dealer Sells vehicle Consumer Uses battery Repurposer New passport Recycler End Manufacturer responsible for ENTIRE first life (Recital 94) KEY TENSION The manufacturer has a legal obligation to keep the passport up-to-date but no practical way to get data from batteries they no longer control.

Our proposal

Incentivize users
to bridge the gap

The manufacturer needs data.
The user has physical access.
A smart contract coordinates the exchange.

System architecture

Battery NTAG 5 Link NFC + I2C master OPTIGA Trust M ECDSA signing $0.81 / battery Phone NFC tap Wallet Submit tx < 500ms tap Cardano L1 MPFS trie root / operator COSE signature verify Reward release $18/year per operator Off-chain IPFS / cloud Full passport data EU Registry Art. 13 sync NFC tx Each operator: 1 UTxO holding MPT root. Millions of batteries as leaves. No on-chain bloat.

The user experience: one NFC tap

1 COMMIT User mints commitment UTxO on-chain Proves intent NOW ~0.2 ADA 2 TAP Phone taps battery NFC with commitment tx hash BMS signs state + hash < 500ms, no internet 3 SUBMIT Submit reading on-chain consuming commitment Reward released ~0.3 ADA + reward
Single-use
Commitment consumed — no replay
No internet
NFC powered by phone field
Trustless clock
Blockchain slot = timestamp

Hardware-signed BMS readings

A $0.81 module on every battery

What it proves

✓This specific BMS produced this data
✓Nobody modified it after leaving the chip
✓It was produced in response to a fresh challenge
✗Sensors are physically accurate (residual risk)

Bill of materials

NTAG 5 Link
$0.35 (1M vol)

OPTIGA Trust M
$0.40 (1M vol)

Antenna + passives
$0.06

$0.81

0.2% of EV BMS cost

User reporting incentives

Manufacturer Funds reward pool Smart Contract Validates + pays User Taps + submits ADA deposit reward signed reading Smart contract guarantees: • Manufacturer cannot refuse to pay for a valid report • Cannot selectively ignore unfavorable readings • All submissions are public

Ownership transfer

One atomic transaction at point of sale

Before sale

  • Seller holds ownership token
  • Seller can claim reporting rewards
  • Buyer has no verified data
→

Transfer transaction

  • Token moves seller → buyer
  • Fresh signed BMS reading attached
  • Both parties sign (mutual consent)
  • Condition at handover: on-chain forever
→

After sale

  • Buyer holds token + reporting right
  • Seller can no longer claim rewards
  • Dispute? On-chain evidence exists

Full chain: Manufacturing → Owner 1 → Owner 2 → … → Repurposing → Recycling. Each handover includes a signed condition snapshot.

Payload: CBOR + COSE_Sign1

Existing IETF standards, not invention

COSE_Sign1 (RFC 9052)

Same signing envelope as:

• EU Digital COVID Certificate

• Mobile driving licences (ISO 18013-5)

• WebAuthn / FIDO2

CBOR (RFC 8949)

Why not JSON:

• Deterministic encoding (signable)

• Compact (integer keys, binary)

• Integer-only: no floats, no strings

• Cardano-native (ledger is CBOR)

Payload

160–200 B

Base reading (SoH, cycles, voltage, temp)

360–430 B

With 96 cell voltages

Fits in 1 NFC tap. Fits in 1 Cardano tx.

Cost breakdown

ComponentCostNotes
NFC + signing module$0.81 / batteryAt 1M volume. 0.2% of EV BMS cost.
On-chain (all EU operators)$1,800–3,600 / year~200 operators, daily trie root updates
Per operator (e.g. BMW)~$18 / yearOne UTxO, one tx/day, regardless of battery count
User reward1–2 ADA / readingMonthly. Funded by manufacturer's reward pool.
Commit + submit~0.5 ADAPer reading (commitment + submission tx)
Off-chain storage$0.10–0.50 / GB / monthIPFS pinning or equivalent

Even at 10x ADA price, operator cost = ~$180/year. Trivial for any battery manufacturer.

Five genuine blockchain value-adds

Each requires a blockchain. A centralized database cannot provide them.

01

Tamper-evident history

Can't alter past readings

02

Trustless incentives

Contract guarantees reward

03

Commitment clock

Proves intent to read NOW

04

Ownership-gated reporting

Token = reporting right

05

Single-use challenge

eUTxO consumed: no replay

Trust chain

Cells Physics Analog FE V, I, T BMS MCU CBOR Secure Element ECDSA sign NFC Tap Phone Submit Cardano Verify WEAKEST LINK MCU → SE: signs whatever MCU gives it MITIGATIONS: Schema validation Plausibility checks Workshop EIS Physical tamper-evidence (CBOR conformance) (SoH can't increase) (independent measurement) (board modification = high bar)

EU registry integration

Cardano L1 MPFS trie roots Adapter Middleware Sync + translate EU DPP Registry (Art. 13) Operational July 2026 Without registry entry = legally non-compliant = product seized at border. The EU is technology-neutral. Blockchain is permitted, not mandated. But the registry sync is mandatory.

Next steps

Q2 2026
Hardware prototype — NTAG 5 Boost + OPTIGA Trust M on a reference BMS board
Q3 2026
Standardization — Propose CIP for signed BMS readings + engage ISO/SAE
Q4 2026
Pilot — Partner with a battery manufacturer for real-world test
Q1 2027
EU registry adapter — Build when Art. 13 API specification is published
Feb 2027
Battery passport mandatory — System operational
2027+
Regulatory engagement — Propose signed BMS readings to Commission as implementing act

The battery passport is coming.
The data bridge isn't built yet.
We can build it.

lambdasistemi.github.io/eu-digital-product-passport