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 (X), 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 (Y) 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 (X), 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 (Y) 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 . <EOS>