1. Main Application and Functions

1.1 Application

This test system is used for compression (crush) and nail penetration performance testing of electric vehicle (EV) traction/power batteries. The test bench is designed and operated in accordance with the following standards:

1. GB/T 31467.3-2015
        Lithium-ion traction battery pack and system for electric vehicles —      Part 3: Safety requirements and test methods

2. GB/T 31485-2015
        Safety requirements and test methods for traction battery of electric      vehicles

2. Goods Configuration and Technical Parameters

2.1 Basic Requirements

2.1.1 Test Space Dimensions

L 3000 mm × W 3000 mm

2.1.2 Test Machine Type

Horizontal type, with an open (un-enclosed) crush area.

2.2 Test Requirements

2.2.1 Current GB/T 31467.3-2015 Test Method Requirements

• Crush platen type: A semi-cylindrical platen with radius 75 mm. The length of the semi-cylinder shall be greater than the height of the battery under test, but not exceed 1 m.

• Crush direction: X-axis and Y-axis directions (vehicle driving direction is X-axis; the other horizontal direction perpendicular to driving direction is Y-axis).

• Crush endpoint: Stop crushing when the crush force reaches 200 kN or when the deformation reaches 30% of the overall dimension along the crush direction.

• Hold time: Maintain the crush force at that condition for 10 min.

• Observation: 1 h.

2.2.2 Current GB/T 31485-2015 Test Conditions for Cell (Single Battery)

GB/T 31485-2015, 6.2.7 Crush

• Crush direction: Apply force perpendicular to the direction of the cell plates (electrodes).

• Crush platen type: A semi-cylindrical platen with radius 75 mm, with length L greater than the cell dimension.

• Crush speed: (5 ± 1) mm/s.

• Crush endpoint: Stop crushing when voltage reaches 0 V, or deformation reaches 30%, or crush force reaches 200 kN (whichever occurs first).

• Observation: 1 h.

GB/T 31485-2015, 6.2.8 Nail Penetration

• Use a high-temperature-resistant steel nail of Φ5 mm to Φ8 mm, penetrate at a speed of (25 ± 5) mm/s, perpendicular to the direction of the cell plates (electrodes), fully penetrating the cell.

• The penetration location should be near the geometric center of the penetrated surface.

• The nail shall remain in the cell.

• Observation: 1 h.

2.2.3 Current GB/T 31485-2015 Pressurization Test Conditions for Battery Module

GB/T 31485-2015, 6.3.7 Crush

• Crush platen type: A semi-cylindrical platen with radius 75 mm. The length of the semi-cylinder shall be greater than the module dimension, but not exceed 1 m.

• Crush direction: Same as the direction most likely to be subjected to crushing in the vehicle layout.

• If such direction cannot be determined, apply force perpendicular to the arrangement direction of the single cells.

• Crush speed: (5 ± 1) mm/s.

• Crush endpoint: Stop crushing when the module deformation reaches 30%, or when the crush force reaches the greater of:

  Number of cells in contact with the crush surface (n) — Crush force (kN)

• n = 1: 200 kN

• n = 2–5: 100 × n kN

• n > 5: 500 kN

1. 1000 times the module weight, and

2. the force value specified in the table below.

• Hold time: 10 min.

• Observation: 1 h.

GB/T 31485-2015, 6.3.8 Nail Penetration

• Use a high-temperature-resistant steel nail of Φ6 mm to Φ10 mm, penetrate at a speed of (25 ± 5) mm/s, perpendicular to the direction of the cell plates (electrodes), and sequentially penetrate at least 3 single cells (the nail shall remain in the module/battery).

• Observation: 1 h.