I am powering an array of LED lights via the car alternator (the LEDs are connected to the car battery leads, but only run when the engine is on). The problem with this setup is that the natural alternator/battery voltage spikes cause the LEDs to flicker slightly. I would like to remove this flickering, however I am unsure how. The setup is an array of 12v LED strip lights. Should I use capacitors or some other method? Note that there is a large number of individual LED strips, totaling about 30 amps of current draw.
A high-quality car capacitor should work. The bigger it is the smoother the signal. Bigger capacitors do take longer to charge and cost more.
Just be careful it does not short, there is no overvoltage, it does not get connected backward, and it can handle your current load. If something is wired wrong, these capacitors may explode. Just make sure the top of the capacitor is not pointed to anything important and any escaping gasses can vent somewhere safe in the event of an explosion.
A fuse or better yet breaker which automatically resets would be useful to prevent a short from damaging setup.
A switch which can disconnect the capacitor when the engine is not running may save your battery life.