Comparing the Cold-Cranking Performance of Lead-Acid and Lithium Iron Phosphate Batteries at Temperatures below 0 °C
Sophia Bauknecht, Florian Wätzold, Anton Schlösser, Julia Kowal
Abstract
Six test cells, two lead–acid batteries (LABs), and four lithium iron phosphate (LFP) batteries have been tested regarding their capacity at various temperatures (25 °C, 0 °C, and −18 °C) and regarding their cold crank capability at low temperatures (0 °C, −10 °C, −18 °C, and −30 °C). During the capacity test, the LFP batteries have a higher voltage level at all temperatures than LABs, which results in a higher power and energy output. Moreover, LFP batteries have a lower capacity decline and a lower energy decline for decreasing temperature. Regarding the cold-cranking test definition, the LABs passed the test at 0 °C, −10 °C, and −18 °C, but not at −30 °C. The LFP batteries passed the test at 0 °C and −10 °C. At −18 °C, only two of the four LFP batteries passed, while all LFP batteries failed the test at −30 °C. For comparability between technologies, it is suggested to redefine the requirements of the standard test in terms of power or energy. With this redefinition, the LFP battery can generate comparable cold-cranking results till −18 °C.