Temperature stability Clause Samples

Temperature stability. The ideal operating temperature of lith- ium batteries ranges from 20 °C to 40 °C. In this temperature range, lithium ion batteries are most efficient, while their aging behavior is still acceptable. At temperatures below zero, cells may be irreversibly damaged if charged, for example when lithium is deposited on the anode (“lithium plating”). In the worst case, this may result in an inter- nal short circuit. Most lithium ion cells are not conceived for operating and storage at tempera- tures above 60 °C. At higher temperatures, the pressure within lithium ion cells may increase, inflammable gases are released, cells may ignite, right up to self-accelerating “explosive” burning of the battery (ther- mal runaway). This makes it dangerous to leave fully charged mobile phones or laptops on the hot dash board in the car on sunny summer days, as tempera- tures inside the car may reach up to 80 °C. If devices are immediately used at such high temperatures, this results in further heating and damage or failure.