Hopefully it is less than the solar panel controller output voltage.
Does the amperage increase with each additional solar panel.
Measure the solar panel controller output voltage try to get maximum voltage by angling the panels.
Since each panel is 12v and the battery bank you want to charge is 24v then you need to series your system to increase the voltage.
Measure the battery voltage.
For safety use the open circuit voltage to calculate series connections in this case the 100 watt panel has 22 5 volts open circuit and 5 29 amps.
You can either wire multiple panels in series to increase voltage with current amps remaining the same as any one panel or wire the panels in parallel to increase current with the voltage output remaining the same as any one panel.
In arranging solar panels you have two options for modifying the power output according the ohm s law.
It may be that you can never get more than 12 13v.
With parallel solar panels the positive terminal from one panel is connected to the positive terminal of another panel and the negative terminals of the two panels are connected together.
In fact by wiring several solar panels in series we increase the voltage keeping the same current while wiring them in parallel we increase the current keeping the same voltage.
When you intend to wire two panels produced by different vendors the vendors are not the problem.
If it is proceed.
How much energy does a solar panel produce.
For the sake of example if you are getting 5 hours of direct sunlight per day in a sunny state like california you can calculate your solar panel output this way.
When stringing panels in parallel each additional panel increases the current amperage of the circuit however the voltage of the circuit remains the same equivalent to the voltage of each panel.
Connect the ve solar controller output lead to the ve.
For example if the solar panel is rated at 175 watts and the maximum power voltage vmp is given as 23 6 volts then calculate the current as 175 watts divided by 23 6 volts which is equal to 7.
Wiring solar panels in parallel causes the amperage to increase but the voltage remains the same.
Though mixing different solar panels is not recommended it s not forbidden and things would be ok as long as each panel s electrical parameters voltage wattage amps are carefully considered.