In this paper we report on the characteristics and performance of a new rechargeable Li-LixMnO2 3 V battery system developed at Tadiran. The behavior of AA cells of an 800 to 750 mAh capacity is described in terms of charge-discharge curves, cycle life, and low-temperature and high-current performance. At charging regimes around C/10, more than 350 cycles at 100% DOD could be obtained. These batteries have a unique cell chemistry based on LiAsF6/1,3-dioxolane/tributyl amine electrolyte solutions which provide internal safety mechanisms that protect the cells from short circuit, overcharge, and thermal runaway upon heating up to 135°C. This behavior is due to the fact that the electrolyte solution is stable at low-to-medium temperatures but polymerizes at temperatures over 125°C.