Albert Barnes Commentary 1 Kings 22:35

"And the battle increased that day: and the king was stayed up in his chariot against the Syrians, and died at even; and the blood ran out of the wound into the bottom of the chariot." — 1 Kings 22:35 (ASV)

The battle increased—that is, the tide of battle rose higher .

The king was stayed up in his chariot—The king’s wound made it impossible for him to remain standing without help. He therefore had attendants support him in his chariot so his soldiers would not lose heart, which they surely would have done if they knew of his peril. Ahab must not be denied the credit of right princely fortitude on this occasion.

The midst of the chariot—This literally refers to the “bosom” of the chariot, which is the rounded front and the adjoining portion of the standing board. The blood would have naturally collected here, forming a pool in which the king and his charioteer must have stood.