A capacitor is an energy-saving device in an electrical field. The potential (Static Voltage) difference between their plates is close to that of a small rechargeable battery.
It is a passive electronic component with two endpoints. The purpose is to store the electrical energy and, if necessary, give back the circuit this energy.
Is it just going to keep building up charges or to hit a point where it can no longer charge or can be damaged?
The charging of a capacitor is extremely easy. It is powered by connecting to a source of DC voltage, which could be a battery or a DC power supply. When the capacitor is wired to the DC voltage source, it will charge the voltage from the source of the DC voltage.
Suppose we have a 9-volt battery and we connect it to a capacitor, so it will charge up to 9 volts. Similarly, if 15 v battery connected to the capacitor will charge up to 15 volts. The only thing to do is connect the positive side of the DC voltage source to the positive side of the capacitor (the long lead) and the negative side of the DC voltage to the negative side of the capacitor (the shorter lead).
Mostly a resistor is often used in series with the capacitor and voltage source to decrease the amount of current flowing through the capacitor so that the capacitor is not harmed.
The charging of the capacitor should be below the voltage rating, which is specified. The capacitor may explode if the charging of a capacitor to a voltage exceeds beyond its voltage level because the power load is not limited at all.
It depends on the type of capacitor. In the case of electrolytic capacitor, they are clearly marked with the working voltage, which must never be exceeded. Most of the capacitor tolerate a minor overvoltage without obvious damage, but normally overvoltage will result in a short circuit. If a capacitor has a large capacity then it can result in a big explosion. Smaller amounts are literally exploded with flames, with a loud crack, pop and fizzle.