Electrode group, secondary battery, battery pack, vehicle and fixed power source

Provided are an electrode group having excellent low-temperature characteristics and hardly causing self-discharge, and a secondary battery, a battery pack, a vehicle, and a stationary power supply including the electrode group. According to one embodiment, an electrode group is provided. The electrode group 500 includes a positive electrode 51, a negative electrode 52, and a separator 53. The positive electrode 51 includes a positive electrode active material containing layer 510 containing a positive electrode active material. The negative electrode 52 includes a negative electrode active material containing layer 520 containing a negative electrode active material. The separator 53 is located at least between the positive electrode and the negative electrode. The separator 53 includes an organic fiber layer 531, first solid electrolyte particles 533a, and second solid electrolyte particles 533b. The organic fiber layer 531 includes organic fibers 531a. The first solid electrolyte particles 533a are in contact with the organic fibers 531a and the positive electrode active material containing layer 510. The second solid electrolyte particles 533b are in contact with the organic fibers 531a and the negative electrode active material containing layer 520. [Selection diagram] Fig. 1