L R AS Published on Sunday 24 September 2023 - n° 458 - Categories:lithium batteries
What causes batteries to deteriorate and how can their life be extended?
Germany's Volytica Diagnostics points out that each cell type, and device subspecies, has a unique vulnerability to degradation, influenced by use and other factors. Some cells thrive at low temperatures, others excel at high currents.
Battery ageing is either related to time (in the case of "calendar" ageing) or to use (since charging and discharging represent "cyclic" ageing). Both forms of ageing contribute to a decrease in capacity and efficiency, as well as an increase in internal resistance as ions become permanently trapped in unpleasant secondary reactions.
Temperature plays a central role in battery life. Most cellular chemicals benefit from being stored and rested at low temperatures, below 20°C, because this slows down calendar ageing by reducing the risk of secondary reactions.
Lithium-ion (li-ion) batteries are generally safe. However, under certain conditions - at cold temperatures, under high current or with an already full host electrode - they can undergo lithium plating. Plating is a form of residue that occurs when lithium ions form metallic deposits inside battery cells. Over time, this process can build up and eventually lead to internal short circuits that can trigger a thermal runaway.
The state of charge has a considerable impact on the life of the battery. The inactive SOC, during non-use (i.e. calendar ageing), and the range or window of the SOC during operation (i.e. cyclic ageing) are important.
Other interesting information can be found in the article
https://www.pv-magazine.com/2023/09/19/the-battery-cycle-part-two-device-lifespan/
PV Magazine of 19 September 2023
