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1 Quick Reference
Welcome
What is Self-discharge?
Self-discharge of an electrical cell is the loss of charge over time while not connected to any load.
Some amount of self-discharge is a normal attribute resulting from chemical reactions taking place
within the cell. Additional self-discharge can result from leakage current paths existing within the cell.
Particulate contaminants and dendrite growths produce internal "micro-shorts", creating such
leakage current paths. These are not normal attributes and they can lead to catastrophic failure of the
cell. For this reason it is a priority to evaluate cells for self-discharge.
Electrically, self-discharge can be modeled as a high-value resistance existing in parallel across the
cell. Note that self-discharge current is very difficult to measure in practice. Usually a defective cell
can only be detected after days or weeks of aging. This is where the proprietary technology of the
Keysight BT2152A/B Self-Discharge Analyzer provides a superior method of measuring self-discharge
over other traditional methods.
Advantages of the Keysight BT2152A/B Self-Discharge Analyzer
The Keysight BT2152A/B Self-Discharge Analyzer uses a proprietary measurement technique to
determine the open-circuit discharge of the cell due to its internal parallel resistance. This proprietary
direct measurement technique lets you determine the quality of the cell within one to two hours after
the cell has been initially charged and rested. This can significantly reduce the test time required to
determine the self-discharge characteristic of the cell due to internal parallel resistance. Key test
features are as follows:
The voltage applied to the cell is quickly matched (±5 μV) to the actual cell voltage. This minimizes
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any new charge or discharge and limits any new RC settling to a minimum.
The voltage applied to the cell is very stable (±10 μV
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current noise on the self-discharge current measurement.
For Keysight Model BT2152A, the measurement system accurately measures low-level self-discharge
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currents to ± (0.33% of reading + 1 μA).
For Keysight Model BT2152B, the measurement system accurately measures low-level self-discharge
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currents to ± (0.3% of reading + 0.25 μA).
Contact Keysight Technologies
Click
www.keysight.com/find/assist
Alternatively you can contact your Keysight Technologies representative.
For more information about Li-Ion cell self-discharge and Keysight's self-discharge measurement
solution, refer to www.keysight.com/find/self-discharge.
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) to minimize continuing charge redistribution
peak
to contact Keysight for warranty, service, or technical support.
Keysight BT2152A/B Operating and Service Guide
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