How to write an insulation test report for energy storage batteries

How to test battery cell insulation resistance?

Battery cell insulation resistance testing is generally carried out as follows (*1): DC voltage is applied between each cell’s anode and cathode, and the insulation resistance is measured. DC voltage is applied between each cell’s electrodes and enclosure, and the insulation resistance is measured.

How to test an energy storage system?

The energy storage system's insulation resistance is typically tested using the existing BMS (Battery Management System) and its standards. The bridge method is employed for measurement, in conjunction with the PCS (energy storage converter) system. The insulation test principle of the entire energy storage system is shown in Figure 1-1.

What voltage is used in battery insulation resistance testing?

The test voltage is the voltage that the insulation tester applies to the cell under test. The appropriate test voltage varies from battery to battery. DC voltage of 100 V to 200 V is generally applied in battery cell insulation resistance testing. Recently, it has become more common to use a low voltage such as 5 V or 50 V.

How does a battery insulation tester work?

Insulation testers use either the resistance method or the constant-current method to provide discharge functionality. When testing battery cells, the constant-current method offers faster discharging, which translates into shorter test times.

What are the standards and principles of DC insulation test?

According to the Gb/T18384.1-2015 standard for on-board rechargeable energy storage systems, the BMS is required to conduct insulation tests on the integrated state of all components of the power lithium-ion battery system and use the insulation resistance value to calculate the insulation state.

Why is insulation resistance measurement important?

Insulation resistance measurement serves as an important test for detecting defects on lithium-ion battery (LIB) cell production lines. Structurally, it’s necessary to keep the anode and cathode, as well as the electrodes and enclosure (case), insulated from each other.