UL 1973 Test and Sample Requirements

Tests required in UL 1973 cover electrical, electromagnetic, mechanical, environmental, and failure tolerance. Non-compliant test results include explosion, fire, combustible vapor concentrations, electric shock hazard, leakage, rupture, and loss of protection controls.

UL 1973: Electrical Testing

• Ability to withstand high voltage without electrical breakdown
• Electrical connections must be properly connected and secure
• Battery maintains thermal stability when exposed to high temperatures
• Capacity to withstand sudden, and prolonged, increases of current
• Must demonstrate it can safely interact with required external sources
• A non-compliant result can’t occur when the battery is exposed to the following charging/discharging conditions: overcharge, overload under discharge, overdischarge, high rate of charge, and imbalanced charging

UL 1973: Electromagnetic Immunity Evaluation

Battery systems must operate without damage, or interference, when exposed to the following conditions:

• High-voltage electrostatic discharge
• Radio-frequency electromagnetic fields and low frequency electromagnetic energy
• Sudden bursts of electromagnetic energy caused by switching circuits
• Voltage spikes caused by power surges
• Common-mode radio-frequency interference

UL 1973: Mechanical and Environmental Testing

• Battery must have structural integrity and the ability to withstand applied testing forces
• Must demonstrate resistance to impact damage
• Ability to operate safely when exposed to repeated temperature changes
• Demonstrates the battery can resist moisture ingress to prevent corrosion and damage

UL 1973: Tolerance to Internal Cell Failure Test for Lithium-ion

• Testing is completed to initiate thermal runaway in a single cell
• Test requires that fire does not propagate, or explosion occur, from the test cell
• Evaluates cell spacing, and design protections, intended to mitigate excessive heat spread during normal and abnormal conditions