I was also going to post this. I saw this and wondered if it works that much better, and what was involved in putting one in. I really want to charge my car on the controller instead of using a separate battery charger.
I got the exact same capacitor they sell off an old VCR! I just saved myself $1.50. If you wire them in parallel the capacitance is added, so you should get a 135sec charge! It makes sense to triple the charge time when you replace a 50mAH battery with a 150mAH, right?