Non-aqueous electrolyte secondary battery and battery pack

摘要

A non-aqueous electrolyte secondary battery of an embodiment includes an exterior member, a negative electrode containing a titanium-containing oxide housed in the exterior member, a positive electrode housed in the exterior member, a separator housed in the exterior member and arranged between the positive electrode and the negative electrode, and a non-aqueous electrolyte solution housed in the exterior member. At least one type or more chain carbonates are contained in a solvent of the non-aqueous electrolyte solution. A self-diffusion coefficient of the chain carbonate in −20° C. is front 1.4×10−10 to 2.0×10−10 m2/sec.

主权项

1. A non-aqueous electrolyte secondary battery comprising:
an exterior member; a negative electrode containing a titanium-containing oxide housed in the exterior member; a positive electrode housed in the exterior member; a separator housed in the exterior member, and arranged between the positive electrode and the negative electrode; and a non-aqueous electrolyte solution housed in the exterior member, wherein at least one type or more chain carbonates are contained in a solvent of the non-aqueous electrolyte solution, a self-diffusion coefficient of the chain carbonate in −20° C. is from 1.4×10−10 to 2.0×10−10 m2/sec, the separator includes a hole having a diameter of from 10 to 100 μm, Rsol<20 Ω·cm2 and Rct<120 Ω·cm2 are satisfied where the magnitude of resistance of the non-aqueous electrolyte secondary battery at a time of application of an alternating-current voltage of 1 kHz in −20° C. is Rsol, and the magnitude of resistance at a time of application of an alternating-current voltage of 0.1 Hz is Rct, and Rsol/Rct>0.16 is satisfied where the magnitude of resistance of the non-aqueous electrolyte secondary battery at a time of application of an alternating-current voltage of 1 kHz in −20° C. is Rsol, and the magnitude of resistance at a time of application of an alternating-current voltage of 0.1 Hz is Rct, the non-aqueous electrolyte solution includes lithium electrolyte, and the lithium electrolyte includes LiPF6 and at least one of LiBF4, LiBOB (lithium bis (oxalate) borate), LiH2PO3, Li2HPO3, Li2PO2, LiPO2F2, LiFSI (lithium bis (fluorosulfonyl) imide), LiTFSI (lithium bis (trifluoromethanesulfonyl) imide), LiClO4 (lithium percrorate), and LiAsF6 (lithium hexafluoroarsenate).