Figure 1. The equivalent circuit of a solar cell. From Wikipedia's Theory of solar cells.
To understand the electronic behavior of a solar cell, it is useful to create a model which is electrically equivalent, and is based on discrete ideal electrical components whose behavior is well defined. An ideal solar cell may be modelled by a current source in parallel with a diode; in practice no solar cell is ideal, so a shunt resistance and a series resistance component are added to the model. The resulting equivalent circuit of a solar cell is shown on the left. Also shown, on the right, is the schematic representation of a solar cell for use in circuit. [Emphasis mine.]
If the solar cell is behaving as a constant current source then it doesn't matter how many you put in series, you can only get IL from the combination. If, for example, IL = 1 A then two or more panels in series will give 1 A into a short circuit.