Tesla Megapack 2 and Megapack 2XL 2023

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(52.3°F) to a maximum surface temperature of 16.8°C (62.2°F). Similarly, as plotted in Figure 14, the 24 thermocouples installed on the instrumented wall also gentle rose throughout the test and fluctuated slightly with the outdoor environmental conditions (i.e., wind blowing, sun exposure, increasing ambient temperatures). The maximum temperature measured on the instrumented wall was 25.9°C (78.6°F), which was temperature rise of 5.5°C (9.9°F) above its ambient temperature at the start of the test. Note, the temperature rise above ambient reported in Table 5 can be attributed to the environmental conditions during the 21⁄2-hour test and are not directly related to the thermal runaway of the seven cells within the initiating MP2. As these measurements are surface temperatures, the temperature rise within the front target surface and the instrumented wall surface is predominantly due to the sun heating up those surfaces during the test (the test was run between 11 am and 1:30 pm on a mostly sunny day). These temperature measurements indicate an exposure surface 5 ft (1.52 m) to the side and adjacent MP2 cabinets 8 ft (2.44 m) in front were not affected by the thermal runaway of the seven cells within initiating battery module.
Figure 13 Front target external surface temperature 8 ft (2.44 m) directly in front of the initiating module.
FEI Project # 22035 Page 26 01/23/2023 22035-03R (MP2 and MP2XL FPE Report)