Sulfide solid electrolyte and method for manufacturing same

A sulfide solid electrolyte to be used for a lithium-ion secondary battery, the sulfide solid electrolyte comprising:

• an argyrodite crystal phase comprising Li, P, S, and Ha, wherein
• the Ha is one or more halogen elements comprising at least Cl,
• a content ratio represented by [Ha]/[P] (atomic ratio) is 1.3 or more, where [P] is a content of the P and [Ha] is a total content of the Ha,
• in a 35Cl-NMR spectrum,
• an area intensity ratio represented by SB/SA is 3.5 or more, where SA is an area intensity of a peak observed at 0 ppm to 30 ppm and SB is an area intensity of a peak observed at −150 ppm to 0 ppm, or
• a peak is observed at −150 ppm to 0 ppm and no peak is observed at 0 ppm to 30 ppm, and
• the 35Cl-NMR spectrum is measured under the following conditions:
• measurement is made using LiCl as an external standard, a chemical shift position having a highest intensity in an obtained 35Cl-NMR spectrum is set to 9.93 ppm;
• and a 35Cl-NMR measurement is made to obtain the 35Cl-NMR spectrum under conditions of a probe:
• a probe for 3.2 mm solid, a measurement condition:
• a single pulse method, a pulse width:
• 2.45 μs, an observation center:
• 20 ppm, an observation width:
• 1000 ppm, a relaxation delay:
• 10 sec, a cumulative number:
• 1024, and a rotation speed:
• 15 kHz.