This paper discusses the comprehensive detection of the open circuit voltage of automobile battery as well as discharge current, final voltage and environment temperature of the battery. Then it calculates the electromotive force, internal resistance, cold cranking ampere and charging capacity of the battery under 25℃, and demonstrates through thorough analysis of automobile starter battery failure mechanism the characteristics of various states of battery, including open circuit, single circuit, dead short circuit, vulcanization and performance degradation. Based on the analysis, this paper proposes the health diagnosis scheme of automobile starter battery, and for practical purpose, integrates health diagnosis with emergency ignition function and develops the emergency ignition apparatus of automobile starter battery