NOVELTY - A non-aqueous electrolyte secondary battery comprises electrode body consisting of positive electrode and negative electrode arranged on both sides of separator, battery case which accommodates electrode body inside, pressure-type electric current interruption mechanism which interrupts charge-and-discharge electric current when internal pressure of battery case exceeds working pressure, and gas forming agent which generates gas when positive electrode electric potential exceeds a gas-evolution electric potential.    USE - A non-aqueous electrolyte secondary battery used as power supplies for motor vehicles, such as hybrid vehicle or electric vehicle, factories, or domestic power supply.    ADVANTAGE - Safety of battery when positive electrode electric potential exceeds gas-evolution electric potential can be improved without degrading battery characteristic.    DETAILED DESCRIPTION - A non-aqueous electrolyte secondary battery comprises electrode body consisting of positive electrode and negative electrode arranged on both sides of separator, battery case which accommodates electrode body inside, pressure-type electric current interruption mechanism which interrupts charge-and-discharge electric current when internal pressure of battery case exceeds working pressure, and gas forming agent which generates gas when positive electrode electric potential exceeds a gas-evolution electric potential. Positive electrode contains positive electrode active material particle (1) in which part of surface of positive electrode active material particle is covered with insulating particle (3) which consists of zirconium dioxide (ZrO2), aluminum oxide (Al2O3), titanium dioxide (TiO2), and/or boron trioxide (B2O3), positive electrode active material particle has particle size of 4-8 mu m micrometers, and insulating particle has particle size of 0.03-0.2 mu m. Ratios of number-of-moles of element except oxygen element which comprises the insulating particle with respect to total molar number of transition metal element which comprises the positive electrode active material particle is 0.1-1 mol.%. Coverage of insulating particle on surface of positive electrode active material particle is 6-20%.    DESCRIPTION OF DRAWING(S) - The drawing shows a cross-sectional diagram of the positive electrode active material particle.    Positive electrode active material particle (1)    Insulating particle (3)    Boundary (5)