# WIA-AUTO-028: Solid-State Battery Standard
## Phase 1: Data Format and Specifications

**Version:** 1.0.0
**Status:** Active
**Last Updated:** 2025-12-27
**Category:** AUTO / Mobility

---

## 1. Overview

Phase 1 of WIA-AUTO-028 establishes foundational data structures and formats for representing solid-state battery information. This phase defines JSON schemas, data models, validation rules, and semantic specifications that enable interoperability between manufacturers, vehicles, chargers, and management systems.

### 1.1 Scope

Phase 1 covers:
- Battery specification schemas
- Performance metrics data structures
- Real-time status and telemetry formats
- Historical data representations
- Diagnostic and fault code schemas
- Test results formats
- Manufacturing and traceability data

### 1.2 Design Principles

- **Machine-Readable:** All data uses JSON format with strict schemas
- **Self-Describing:** JSON-LD context provides semantic meaning
- **Extensible:** Additional fields allowed for future expansion
- **Validated:** All data must pass schema validation
- **Unit-Explicit:** Units always included, never assumed
- **Timestamped:** ISO 8601 timestamps with timezone

---

## 2. Core Data Schemas

### 2.1 Battery Specification Schema

Complete technical specification of a solid-state battery.

**Schema URI:** `https://wiastandards.com/schemas/auto-028/battery-spec-v1.json`

#### 2.1.1 Required Fields

- `@context`: JSON-LD context URI
- `type`: "SolidStateBatterySpecification"
- `id`: Decentralized Identifier (DID)
- `manufacturer`: Manufacturer information
- `model`: Model designation
- `electricalSpec`: Electrical specifications
- `performanceMetrics`: Key performance indicators

#### 2.1.2 Example

```json
{
  "@context": "https://wiastandards.com/contexts/auto-028/v1",
  "type": "SolidStateBatterySpecification",
  "id": "did:wia:battery:ssb-2025-12345",
  "manufacturer": {
    "name": "WIA Battery Corporation",
    "location": "Seoul, South Korea",
    "certifications": ["ISO-9001", "IATF-16949"]
  },
  "model": "WIA-AUTO-028-100-Premium",
  "productionDate": "2025-01-15",
  "serialNumber": "2025011500001",
  "physicalSpec": {
    "dimensions": {"length": 600, "width": 400, "height": 150, "unit": "mm"},
    "mass": {"value": 45, "unit": "kg"},
    "volume": {"value": 36, "unit": "L"}
  },
  "electricalSpec": {
    "nominalVoltage": {"value": 400, "unit": "V"},
    "capacity": {"value": 100, "unit": "Ah"},
    "energy": {"value": 40, "unit": "kWh"},
    "continuousPower": {"value": 150, "unit": "kW"},
    "peakPower": {"value": 300, "unit": "kW", "duration": 30, "durationUnit": "s"}
  },
  "electrolyteType": "sulfide",
  "electrolyteComposition": "Li6PS5Cl",
  "performanceMetrics": {
    "gravimetricEnergyDensity": {"value": 450, "unit": "Wh/kg"},
    "volumetricEnergyDensity": {"value": 1100, "unit": "Wh/L"},
    "fastCharge10to80": {"value": 12, "unit": "min", "power": 150, "powerUnit": "kW"},
    "cycleLife": {"value": 3000, "condition": "80% DOD", "retentionAtEOL": 80}
  }
}
```

### 2.2 Status and Telemetry Schema

Real-time battery operational data.

**Schema URI:** `https://wiastandards.com/schemas/auto-028/battery-status-v1.json`

#### 2.2.1 Status Parameters

| Parameter | Type | Unit | Update Rate | Description |
|-----------|------|------|-------------|-------------|
| stateOfCharge (SOC) | number | % | 1-10 Hz | Available charge percentage |
| stateOfHealth (SOH) | number | % | 0.1-1 Hz | Battery health/capacity retention |
| stateOfPower (SOP) | object | kW | 1-10 Hz | Charge/discharge power limits |
| voltage | object | V | 1-100 Hz | Pack and cell voltages |
| current | number | A | 1-100 Hz | Charge/discharge current |
| temperature | object | °C | 0.1-10 Hz | Cell, pack, ambient temperatures |
| power | number | kW | 1-100 Hz | Instantaneous power |

#### 2.2.2 Example

```json
{
  "@context": "https://wiastandards.com/contexts/auto-028/v1",
  "type": "BatteryStatus",
  "batteryId": "did:wia:battery:ssb-2025-12345",
  "timestamp": "2025-12-27T14:30:00Z",
  "stateOfCharge": {"value": 67.5, "unit": "%", "confidence": 0.98},
  "stateOfHealth": {"value": 94.2, "unit": "%"},
  "stateOfPower": {
    "chargeMax": {"value": 120, "unit": "kW"},
    "dischargeMax": {"value": 180, "unit": "kW"}
  },
  "voltage": {
    "pack": {"value": 386.4, "unit": "V"},
    "cellMin": {"value": 3.81, "unit": "V"},
    "cellMax": {"value": 3.87, "unit": "V"}
  },
  "current": {"value": -45.2, "unit": "A", "direction": "discharge"},
  "temperature": {
    "cellMin": {"value": 24.3, "unit": "C"},
    "cellMax": {"value": 28.7, "unit": "C"},
    "cellAvg": {"value": 26.1, "unit": "C"}
  }
}
```

---

## 3. Performance Metrics

### 3.1 Certification Level Requirements

| Metric | Unit | Level 1 Min | Level 2 Min | Level 3 Min |
|--------|------|-------------|-------------|-------------|
| Gravimetric Energy Density | Wh/kg | ≥300 | ≥400 | ≥450 |
| Volumetric Energy Density | Wh/L | ≥700 | ≥900 | ≥1100 |
| Fast Charge (10-80%) | minutes | ≤30 | ≤20 | ≤15 |
| Cycle Life (80% DOD) | cycles | ≥1000 | ≥2000 | ≥3000 |
| EOL Capacity Retention | % | ≥70 | ≥75 | ≥80 |
| Peak Power Density | W/kg | ≥800 | ≥1000 | ≥1200 |

### 3.2 Operating Ranges

All batteries must specify:
- Temperature range (min, max, optimal)
- Voltage range (min, max, nominal)
- Current limits (charge, discharge)
- Power limits (continuous, peak with duration)

---

## 4. Diagnostic Schema

### 4.1 Fault Code Categories

| Category | Prefix | Severity Levels | Examples |
|----------|--------|-----------------|----------|
| Temperature | SSB-T | Info, Warning, Critical | T001: High temp, T002: Low temp |
| Voltage | SSB-V | Info, Warning, Critical | V001: Overvoltage, V002: Undervoltage |
| Current | SSB-C | Warning, Critical | C001: Overcurrent, C002: Short circuit |
| Interface | SSB-I | Info, Warning | I001: High impedance, I002: Delamination |
| Degradation | SSB-D | Info, Warning | D001: Capacity fade, D002: SOH decline |
| System | SSB-S | Warning, Critical | S001: BMS fault, S002: Sensor failure |

### 4.2 Fault Code Structure

```json
{
  "code": "SSB-T001",
  "severity": "warning",
  "timestamp": "2025-12-27T14:30:00Z",
  "description": "Cell temperature exceeds warning threshold",
  "details": {
    "cellId": "module-3-cell-12",
    "temperature": {"value": 42.5, "unit": "C"},
    "threshold": {"value": 40.0, "unit": "C"}
  },
  "recommendedAction": "Reduce power demand, activate cooling"
}
```

---

## 5. Validation Rules

### 5.1 JSON Schema Validation

All Phase 1 data MUST:
1. Conform to published JSON schemas
2. Include @context and type fields
3. Use correct data types for all fields
4. Include units for all numerical measurements
5. Pass cross-field validation (e.g., energy = capacity × voltage)

### 5.2 Unit Validation

Accepted units:
- **Energy:** Wh, kWh
- **Power:** W, kW
- **Capacity:** Ah
- **Voltage:** V
- **Current:** A
- **Mass:** kg
- **Volume:** L
- **Temperature:** C, K (Celsius required for display)
- **Time:** s, min, h

### 5.3 Range Validation

Numerical values must be within physically reasonable ranges:
- SOC: 0-100%
- SOH: 0-100%
- Voltage: >0
- Temperature: -50°C to 100°C (battery operating range)
- Energy density: 100-1000 Wh/kg (current technology bounds)

---

## 6. Data Quality Requirements

### 6.1 Accuracy

- SOC estimation: ±2% at steady state, ±5% during transients
- SOH estimation: ±3% over battery lifetime
- Voltage measurement: ±10 mV
- Current measurement: ±1% of full scale
- Temperature measurement: ±1°C

### 6.2 Precision

Recommended decimal places:
- SOC, SOH: 1 decimal (67.5%)
- Voltage: 1-2 decimals (386.4 V)
- Current: 1 decimal (45.2 A)
- Temperature: 1 decimal (26.1°C)
- Energy density: 0-1 decimals (450 Wh/kg)

### 6.3 Latency

Data freshness requirements:
- Safety-critical (SOC, temperature, faults): <100ms
- Performance data (power, voltage, current): <500ms
- Health metrics (SOH): <60s
- Historical data: No real-time requirement

---

## 7. Implementation Guidance

### 7.1 Data Generation

Implementations SHOULD:
- Generate data at appropriate frequencies
- Include confidence/accuracy metrics for estimated values
- Timestamp all data with microsecond precision
- Handle missing data gracefully (null vs. absent field)

### 7.2 Data Storage

Recommendations:
- Use time-series databases for telemetry (InfluxDB, TimescaleDB)
- Store specifications in document databases (MongoDB, PostgreSQL)
- Maintain audit trail of changes
- Implement data retention policies (min. 2 years for critical data)

### 7.3 Data Transmission

- Use compression for large datasets (gzip, brotli)
- Support incremental updates (only changed fields)
- Implement checksums for data integrity
- Handle network failures gracefully

---

## 8. Compliance and Certification

### 8.1 Level 1 Requirements

- Implement Battery Specification Schema
- Implement Status and Telemetry Schema
- Pass JSON schema validation
- Provide accuracy specifications
- Document data generation methods

### 8.2 Testing

Conformance testing includes:
- Schema validation of sample data
- Cross-field consistency checks
- Unit validation
- Range validation
- Accuracy verification against reference measurements

---

## 9. References

- JSON Schema: https://json-schema.org/
- JSON-LD: https://json-ld.org/
- ISO 8601: Date and time format
- IEEE 754: Floating-point arithmetic

---

**弘益人間 (Hongik Ingan) · Benefit All Humanity**

*WIA - World Certification Industry Association*
*© 2025 MIT License*