Method for verification of precharge in nickel hydrogen batteries

Methods for storing nickel hydrogen batteries and cells continue to be of interest due to the degradation that may occur as a result of loss of precharge within the cells. Most launches require storage of the batteries for a period of time prior to final installation. Knowledge of the state of charge during this time along with the precharge is important. This is especially true for batteries used for integration and testing with the final item, such as a satellite, prior to storage and launch. The loss of cell precharge can occur during these intervals for various reasons. If returned to inactive storage without the proper precautions or maintenance, loss of useable capacity can occur. In this paper a test is discussed which verifies the presence or absence of hydrogen. This allows the user to select the correct method to store the battery for later use.