A non-aqueous electrolyte secondary battery comprising: a positive electrode comprising a positive electrode current collector and a positive electrode material mixture layer formed thereon; a negative electrode comprising a negative electrode current collector and a negative electrode material mixture layer formed thereon; and a non-aqueous electrolyte, characterized in that at least one of said positive and negative electrodes has a positive temperature coefficient of resistance; and said non-aqueous electrolyte contains an additive which is stable in the normal operating voltage range of said battery and is able to polymerize at the voltage exceeding the maximum value of said operating voltage range.