if your lights are dimming or the voltage is dropping, you need a larger alternator. capacitors are a gimmick. the second battery would only help when your engine is off, and you'd still need a battery isolator, a lot more work, and the high output alternator to recharge two batteries instead of just the starter battery.
Pat L
Unregistered guest
Posted on
Screw the cap, just get a seconed battery or just a nice new alt.
1. Install basic splitter $30, splits alternator power into 2 directions
2. Battery isolator, charges the lower voltage battery first. $70
3. Battery sepparater, charges the primary battery first (the engine battery, up to 13.5v) and then after the car is running and drawing little battery power it charges the secondary battery in the trunk or engine. This option is the most expensive, but the most effective. $130
The first two options can leave your engine battery dead and u in a parking lot switching your batteries so you can get home. Option 3 ensures that your engine will always start, but if your alternator is too small to charge both batteries then the secondary battery for the stereo may need to be recharged every so often. This is my setup, and once a month or so i have my batteries on trickle chargers because the local alternator refurbishing center won't do my car for whatever reason and I dont want to order a high performance as i plan to sell this car in the near future.
Hope this helped answer your question about the split charging. Email me is more questions
"2. Battery isolator, charges the lower voltage battery first"
um, no. with an isolator, both the starter battery, and the batteries for the audio system are all charged at the same time, but each of the two circuits are isolated so that the starter battery is never affected by the load from the audio system, allowing you to run the deep cycle car audio circuit batteries to zero, and still start the car with a fresh battery.
A battery isolator isn't that complex of a device. It's a bank of diodes essentially.