Nail penetration tests are a requirement covered in SAE J2464 and US ABC & Freedom Car, SAND-2005-3123 as well as other standards. These tests can be conducted safely inside the ARC® 254 system. Two examples of nail penetration tests are shown in the diagram below. Inside the ARC® 254 we can accurately set and held the test temperature at 25°C and 75°C for the nail penetration tests. The pressure inside the ARC® calorimeter is measured and plotted as a function of time. In these two the tests were conducted in air so external combustion could take place. These tests can also be done in an inert environment. The starting temperature as the largest impact on the measured pressure while there is little variation in the temperature spikes recorded.
Here we see the same data but for two different tests- one run at 25°C and another run at 70°C. We can see that the temperature and temperature rate data is nearly the same for both but there is a considerable increase in the measured pressure form the test conducted at 70°C. In some cases we have found batteries which pass the nail penetration test at room temperature but fail when at elevated temperature. Nail type, speed, and temperature all play a roll in the outcome of these tests.