CYLINDRICAL NONAQUEOUS ELECTROLYTE SECONDARY BATTERY

摘要

To improve the service life of a cylindrical nonaqueous electrolyte secondary battery in cases where the negative electrode active material thereof contains a silicon compound. This cylindrical nonaqueous electrolyte secondary battery (10) comprises: a bottomed cylindrical case main body (12) which houses an electrode body (30); and a cover body (20) which closes an opening of the case main body (12). The electrode body (30) comprises a negative electrode (32) that comprises a negative electrode active material, and the negative electrode active material contains a compound containing silicon (Si). The cover body (20) comprises a current interrupting mechanism (23) which comprises an upper valve body (24) and a lower valve body (26) that is arranged below the upper valve body (24) and is bonded to the upper valve body (24), and which blocks the current path by means of a rise in the gas pressure within a space that is formed between the upper valve body and the lower valve body. The bottom part of the case main body (12) has a thin portion (13) that constitutes at least a part of a ring, and the portion other than the thin portion (13) of the bottom part has a thickness t satisfying 0.25 mm < t < 0.35 mm.