A power battery, characterized in that the power battery comprises: a case comprising two openings opposite to each other; an electrode assembly which is formed by winding a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet around a winding axis, wherein the electrode assembly is disposed in the case, and two opposite ends of the electrode assembly along the winding axis are respectively disposed corresponding to the two openings; a first cap assembly covering one of the two openings, wherein the first cap assembly comprises a liquid injection hole communicating with an interior of the case; a second cap assembly covering the other of the two openings, wherein the second cap assembly comprises a through hole communicating with the interior of the case; in a length direction, the liquid injection hole and the through hole are located on a same side of a central axis of the case, the liquid injection hole comprises a first inlet and a first outlet, the first cap assembly comprises a first blocking member, the first blocking member is disposed between the first outlet and the electrode assembly, and a projection of the first blocking member in the height direction at least partially blocks the first outlet, the first cap assembly comprises a first cap plate, the liquid injection hole and the first blocking member are disposed at the first cap plate, a first guide channel is formed between the first blocking member and the first cap plate, the first guide channel communicates with the first outlet, and an outlet of the first guide channel is oriented towards the central axis of the case. a case comprising two openings opposite to each other; an electrode assembly which is formed by winding a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet around a winding axis, wherein the electrode assembly is disposed in the case, and two opposite ends of the electrode assembly along the winding axis are respectively disposed corresponding to the two openings; a first cap assembly covering one of the two openings, wherein the first cap assembly comprises a liquid injection hole communicating with an interior of the case; a second cap assembly covering the other of the two openings, wherein the second cap assembly comprises a through hole communicating with the interior of the case; in a length direction, the liquid injection hole and the through hole are located on a same side of a central axis of the case, the liquid injection hole comprises a first inlet and a first outlet, the first cap assembly comprises a first blocking member, the first blocking member is disposed between the first outlet and the electrode assembly, and a projection of the first blocking member in the height direction at least partially blocks the first outlet, the first cap assembly comprises a first cap plate, the liquid injection hole and the first blocking member are disposed at the first cap plate, a first guide channel is formed between the first blocking member and the first cap plate, the first guide channel communicates with the first outlet, and an outlet of the first guide channel is oriented towards the central axis of the case.