▎ 摘　　要

NOVELTY - A secondary battery (5) comprises an electrolyte comprising a low viscosity solvent, an electrolyte salt and high dielectric constant solvent, and a negative electrode comprising a negative electrode current collector and a negative electrode active material arranged on at least one surface of the current collector layer. The mass content (B) of low viscosity solvent in the total solvent in the electrolyte, the mass content (C) of electrolyte salt in the electrolyte, and the porosity (P), the coating amount (CW) and the orientation index (OI) of the negative electrode active material layer satisfy a preset relation. The orientation index of the negative electrode active material layer is a ratio of peak area (C004) of 004 feature diffraction peak in an X-ray diffraction pattern of the negative electrode active material layer, and peak area (C110) of 110 feature diffraction peak in the X-ray diffraction pattern of the negative electrode active material layer. USE - Secondary battery used in battery module and battery pack of electrical device (claimed) e.g. car. Uses include but are not limited to mobile phone, notebook computer, hybrid electric vehicle, plug-in hybrid electric vehicle, electric bicycle, electric scooter, electric club car, electric truck, electric train, satellite energy storage system, etc. ADVANTAGE - By using specific negative electrode and electrolyte and designing the specific relationship between the negative electrode battery and the electrolyte, the multiplying power performance of the battery, circulation performance and storage performance can be improved. DETAILED DESCRIPTION - A secondary battery (5) comprises an electrolyte comprising a low viscosity solvent, an electrolyte salt and more than 20 %mass high dielectric constant solvent with respect to total solvent in the electrolyte, and a negative electrode comprising a negative electrode current collector and a negative electrode active material arranged on at least one surface of the current collector layer. The low viscosity solvent has a viscosity of 0.3-0.6 mPa.second at 25° C. The high dielectric constant solvent has a dielectric constant of 30-100 F/m. The mass content (B) of low viscosity solvent in the total solvent in the electrolyte, the mass content (C) of electrolyte salt in the electrolyte, and the porosity (P), the coating amount (CW) (in mg/cm2) and the orientation index (OI) of the negative electrode active material layer satisfy the relation: 1x 10-4≤ (Bx Cx P)/(OIx CW)≤ 1x 10-3. The orientation index of the negative electrode active material layer is a ratio (C004/C110) of peak area (C004) of 004 feature diffraction peak in an X-ray diffraction pattern of the negative electrode active material layer, and peak area (C110) of 110 feature diffraction peak in the X-ray diffraction pattern of the negative electrode active material layer. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of secondary battery. 5Secondary battery