Liquid container and liquid ejection system

A liquid container capable of containing a liquid, comprising:

• a liquid containing portion configured to contain the liquid;
• a liquid inlet port through which the liquid is injectable into the liquid containing portion;
• an atmosphere opening port communicating with the liquid containing portion and through which atmosphere is introducible into the liquid containing portion;
• a first sheet member having a first face that faces outward in a first direction;
• and
• a second sheet member having a second face that faces outward in a second direction that is different from the first direction;
• an atmosphere communicating portion leading to the liquid containing portion from the atmosphere opening port, the atmosphere communicating portion comprising a plurality of atmosphere chambers including:
• a first atmosphere chamber, at least one side of which is defined by the first sheet member, and
• a second atmosphere chamber, at least one side of which is defined by the second sheet member;
• and
• a wall, at least a portion of which is located between the first atmosphere chamber and the second atmosphere chamber, the wall comprising at least one communicating portion;
• wherein the first atmosphere chamber and the second atmosphere chamber are communicably connected to one another via the at least one communicating portion of the wall.