For emergency backup of communications and other industrial equipment, the compact and low-maintenance, MSE series, valve-regulated lead - acid battery has mainly been used in place of conventional flooded types. Because of the keen competition in the communications industry, it is becoming more important to reduce battery maintenance and replacement costs. In addition, operations in extreme environments are becoming more common as networks expand. In response to this trend, the new long-life MSE-AT series has been developed. It has twice the life at normal temperatures, i.e., 13 to 15 years, and increased life at high temperatures. This has been attained by improving the negative electrode and separator to reduce the float-charging current, and by using a highly corrosion-resistant alloy for the positive grid. (C) 2000 Elsevier Science S.A. All rights reserved.