A battery cell , comprising: a housing , being a hollow cylinder with a first opening ; an electrode assembly , arranged in the housing ; an end cover assembly , comprising an end cover , a pressure relief mechanism and a first insulating member , the end cover covers the first opening , the pressure relief mechanism is arranged at the end cover , the pressure relief mechanism is configured to be actuated to relieve the internal pressure of the battery cell when an internal pressure or temperature of the battery cell reaches a threshold, the first insulating member is located on a side of the end cover close to the electrode assembly to isolate the electrode assembly and the end cover , and the first insulating member is configured that a projection of the first insulating member on the end cover along a thickness direction (D) of the end cover covers a projection of the pressure relief mechanism on the end cover along a thickness direction (D) of the end cover to protect the pressure relief mechanism ; wherein the pressure relief mechanism and the first insulating member are provided with a first gap (A) in the thickness direction (D) of the end cover , the battery cell further comprises a flow path, and the flow path is configured to communicate the inner portion of the battery cell and the first gap (A); wherein the flow path comprises a second opening (B) arranged on the first insulating member , and the second opening (B) is configured that a projection of the second opening on the end cover along the thickness direction (D) of the end cover is staggered with the pressure relief mechanism ; wherein a projection of the second opening (B) on the end cover is formed in an arc, and two radius of the end cover pass through two ends of the arc and form a fan shape with the arc, the pressure relief mechanism is located within the fan-shaped range. a housing , being a hollow cylinder with a first opening ; an electrode assembly , arranged in the housing ; an end cover assembly , comprising an end cover , a pressure relief mechanism and a first insulating member , the end cover covers the first opening , the pressure relief mechanism is arranged at the end cover , the pressure relief mechanism is configured to be actuated to relieve the internal pressure of the battery cell when an internal pressure or temperature of the battery cell reaches a threshold, the first insulating member is located on a side of the end cover close to the electrode assembly to isolate the electrode assembly and the end cover , and the first insulating member is configured that a projection of the first insulating member on the end cover along a thickness direction (D) of the end cover covers a projection of the pressure relief mechanism on the end cover along a thickness direction (D) of the end cover to protect the pressure relief mechanism ; wherein the pressure relief mechanism and the first insulating member are provided with a first gap (A) in the thickness direction (D) of the end cover , the battery cell further comprises a flow path, and the flow path is configured to communicate the inner portion of the battery cell and the first gap (A); wherein the flow path comprises a second opening (B) arranged on the first insulating member , and the second opening (B) is configured that a projection of the second opening on the end cover along the thickness direction (D) of the end cover is staggered with the pressure relief mechanism ; wherein a projection of the second opening (B) on the end cover is formed in an arc, and two radius of the end cover pass through two ends of the arc and form a fan shape with the arc, the pressure relief mechanism is located within the fan-shaped range. <EOS>