Measure battery insulation with a voltmeter to detect short circuits between the negative electrode and the enclosure to ensure battery safety and prevent a reduction in the battery’s service life. Removing insulation defect cells prior to the very time-consuming charge/discharge aging process also contributes to a higher yield of aging tests.
The worst-case scenario for insulation failure of a battery is for the outer insulation to short-circuit to the negative electrode and come into contact with the electrolyte. It is therefore extremely important to verify the state of insulation after electrolyte filling. This test is executed with low voltages starting from 0.1 V in order to prevent decomposition of the electrolyte or other negative influences on the performance of the battery.
The outer aluminium of a normal pouch cell is insulated from the electrodes and the electrolyte.
Insulation failure can cause the outer insulation to short-circuit to the negative electrode and come into contact with the electrolyte. The resulting current pathway formed by cracks inside the pouch causes an electrochemical reaction, which results in a significantly reduced the life of the battery cell.
Detect short-circuits between the negative electrode and the enclosure by measuring the DC voltage between the positive electrode and the enclosure. 0 V is the result as a good cell, but if the same voltage as the battery is detected, it indicates that the negative electrode has short-circuits to the enclosure.
Precision DC Voltmeter DM7276
|DC Voltage||100 mV (±120.000 00 mV) to 1000 V (±1000.000 0 V), 5 ranges|
|Basic accuracy||10 V range: ±0.0009% rdg. ±12 μV|
|Temperature||-10.0°C to 60.0°C, combined with sensor Z2001: ±0.7°C (-10°C to 50°C)|
|Measurement support functions||Temperature compensation, Contact check, Comparator, BIN, Absolute value judgment, etc.|
|Power supply||100 to 240 V AC, 50/60 Hz, 30 VA|
|Interfaces||Standard: LAN (100BASE-TX), EXT. I/O, USB flash drive / USB device (USB2.0 Full-Speed). Optional: GP-IB (-02 type only) / RS-232C (-03 type only) / PRINTER (-03 type only)|