Lead-acid battery

A lead-acid battery comprising:

• a container having an opening on one side in a first direction and formed with a housing chamber communicating with the opening;
• a positive electrode and a negative electrode housed in the housing chamber of the container;
• and
• a lid disposed so as to close the opening of the container and has a discharge port formed on an outer surface of the lid, wherein
• a communication chamber is formed inside the lid, the communication chamber being surrounded by a partition wall between the housing chamber and the communication chamber, a facing wall that faces the partition wall in the first direction, and a sidewall that connects the partition wall and the facing wall,
• a communication hole communicating with the housing chamber is formed in the partition wall,
• a vent hole communicating with the discharge port of the lid is formed in the sidewall,
• the communication chamber is provided with an inner wall disposed so as to face the communication hole,
• a first distance between the inner wall and the vent hole in the sidewall is shorter than a second distance between the inner wall and the communication hole, and
• a tip of the inner wall on the other side in the first direction is formed at a position on the other side in the first direction than the vent hole.