The MS920T raises the bar on operating temperature for lithium rechargeable batteries. Rather than the typical 60°C, Seiko Instruments’ coin-type battery operates at up to 85°C. To achieve that temperature watermark, the company leveraged its own sealing technology to meet indoor and outdoor and interior-vehicle applications. The MS920T keeps more than 95% of its initial capacity after 60 days of storage at that temperature (conventional-type batteries lose their capacity to 40% of initial capacity under the same conditions). Discharge characteristics will remain stable even after being overdischarged to 0 V. In addition, it can be charged and discharged more than 100 times with 100% depth of discharge, when the battery is charged and discharged at 3.3 to 2.0 V (estimated based on the design). Specifications include 3-V nominal voltage, 6.4-mAh nominal capacity, and 60-Ω internal impedance. Measuring 9.5 mm in diameter and 2.0 mm high, the battery will find homes in backup power supplies for memory real-time clocks in various electric devices.