lets see, $100+ for a battery, $50+ each for battery cables to the rear where there is space and you have $200.
now lets compare the proper way,
$80 for new squareback alternator, $25 for solid state voltage regualtor. 3 hours or less to wire it in.
so how is that more cost effective for two batteries? two batteries are for more cranking amps when starting like in a diesel truck, once it starts you need to charge those batteries just the same as any vehicle would. and if your having problems charging one battery two is going to be worse
