Safety Requirements for Energy Storage Batteries in the Japanese Market

Interpretation of JIS C 8715-2:2019

Preface

In Japan, energy storage batteries are not yet subject to mandatory PSE certification under the Electrical Appliance and Material Safety Law. However, for market entry, exported energy storage batteries products must comply with JIS C 8715-2:2019 and provide a valid test report. Compliance with this standard is a prerequisite for accessing the Japanese market.

1. Standard Overview

1)Standard Number and Title

• JIS C 8715-2:2019
• Secondary lithium cells and batteries for industrial applications — Part 2: Safety requirements

2)Origin and Scope

Source: Based on IEC 62619:2017, with modifications tailored to Japan’s specific usage conditions and technical requirements.

Scope of Application: Applies to secondary lithium batteries and battery packs for industrial use, including stationary applications.

Typical Applications:

• Stationary applications: telecom, uninterruptible power supplies (UPS), electrical energy storage system, emergency power and similar applications.
• Motive applications: fork-lift truck, golf cart, automated guided vehicle (AGV), railway, marine, etc., excluding road vehicles.

2. Core Safety Test Items

The JIS C 8715-2 standard outlines a comprehensive set of tests designed to evaluate battery safety under severe and abusive conditions. Key categories include:

1)Electrical Safety Tests

• External Short Circuit Test: Simulates output short circuits to verify protective functions against overheating, fire, or explosion.
• Overcharge Test: Assesses the BMS capability to prevent hazards when charged beyond rated voltage/current.
• Forced Discharge Test: Evaluates safety and recovery performance after deep overdischarge.
• Insulation Resistance Test: Verifies insulation between the internal circuit and outer casing to prevent leakage.

2)Mechanical Safety Tests

• Impact Test: Simulates shocks during transport/handling.
• Drop Test: Assesses structural safety under accidental drops.
• Crush Test: Evaluates battery integrity under compression.

3)Environmental & Abuse Tests

• Thermal Abuse Test: Assesses stability under high-temperature exposure.
• Internal Short Circuit Test: Simulates cell-level shorts to ensure risk containment.
• Temperature Cycling Test: Evaluates performance and reliability under rapid temperature variations.

4)System Protection Function Tests

• Overvoltage/Undervoltage Protection
• Overcurrent Protection (charge/discharge)
• Overtemperature Protection

5)Special Safety Tests

• Leakage Test: Ensures no electrolyte leakage under normal and extreme conditions.
• Fire Resistance Test: Evaluates flame resistance of external materials.
• Thermal Runaway Propagation Test: Determines whether cell-level runaway propagates to the entire module.

3. Comparison of Differences between JIS C 8715-2:2019 and IEC 62619:2017