9.3 Cranking performance test 9.3.1 Cranking performance test – Standard temperature 9.3.1.1 After a rest period of up to 24h after preparation according to 6.2, the battery shall be placed in a cooling chamber with (forced) air circulation at a temperature of –18 °C ± 1 °C until the temperature in one of the middle cells has reached –18 °C ± 1 °C.