Lithium carbon-monofluoride batteries for extended ultra-high temperature storage and surface mount applications

Abstract

Industry has dictated a growing need for cells and batteries capable of sustained use and storage in elevated temperature environments. This usage varies from short term exposures for surface mount technology, to the long term service environments of the automotive industry for computer memory backup.The storage temperature for typical lithium carbonmonofluoride (Li/CFx) cells range from -40°C to +6OoC. Accelerated thermal testing has identified three primary failure modes for the standard design as: electrolyte diffusion through the seal, degradation of the polymeric seal material, and internal component corrosion/degradation. All three of these failure modes are essentially related.The electrochemical couple itself should be capable of functioning up to 181°C for the lithium and 450-650°C for the carbon-monofluoride. The lithium of this cell system can further be modified by alloying for increased thermal stability.(Li/CFx) coin cell system has been optimized for high temperature (1 25°C) applications. The optimization was accomplished utilizing the standard BR1225 cell size as a test vehicle. An unique electrolyte formulation and polymeric seal material have resulted in cells that tolerate temperatures up to 125°C for a year without substantial degradation in performance.

Progress towards high-power Li/CFxbatteries: electrode architectures using carbon nanotubes with CFx

“…45,46 Besides medical industries, Li/CF x batteries have been found in a wide range of applications in military, aerospace and electronic devices such as gas meters, cameras, computer clock and memory back-up which mostly require low-to-medium rates. 6,[47][48][49][50] Li/CF x cells exhibit the flexibility to be packed into different shapes such as spiral, coin, cylindrical and pouch based on the specific use. Extensive development on battery packing has been conducted to improve the overall energy density, where lighter materials such as aluminum and plastic are often used for packaging.…”