Primary reserve batteries used in weapons systems are typically not activated until immediately before use. To periodically test the condition of these inactivated batteries, sample batteries are removed from the weapons, activated, tested, and from the tested samples, statistical techniques used to estimate the condition of the stockpile. This takes considerable time and money. In this project non-destructive techniques for determining the condition of these reserve batteries will be considered. Various stimuli to the battery including electrical, mechanical, and thermal together with the batteries' responses to these stimuli will be assessed. Both theoretical analysis of the battery response and experimental verification will be performed to develop a few candidate approaches for non-destructive testing of primary reserve batteries. One of the techniques that will be investigated in more depth is ac impedance measurements at various temperatures for the molten-salt Li-based primary thermal batteries. The present method of monitoring the condition of primary reserve batteries used in weapons systems is to test samples of stockpiled batteries by activating the batteries, and using statistical analysis to estimate the condition of batteries in the stockpile. This method has several drawbacks. It requires that samples be selected for testing, and the selected samples be activated for testing. This means that these particular tested batteries must be replaced and so a procurement process for these replacement batteries must be conducted. Additionally, time and money are spent in performing the statistical analysis to estimate the condition of the batteries in a particular stockpile. Clearly, the development of a non-destructive technique for estimating the condition of a stockpile of reserve batteries can provide considerable savings in time and money. Reducing the cost and time to assess the conditions of primary reserve batteries will be an important result of this project. The same approach developed in this project for non-destructive testing of batteries would be of use in weapons systems across the armed services and therefore benefit the entire Department of Defense (DoD). Furthermore, some of the techniques developed in this program may be applicable to commercial electrochemical systems and for biomedical applications where remote monitoring of implanted defibrillator and pacemaker batteries may benefit from the technology being developed in this project.
Keywords: PRIMARY BATTERIES, RESERVE BATTERIES, THERMAL BATTERIES, BATTERY TESTING, NON-DESTRUCTIVE TESTING
