🔋 KOOBOOK 1Set(6pcs): Ultra-High Capacity 2.7V 500F Farad Capacitor Super Capacitor with Protection Board Review

very good, update: 11/24/2019 use only in the car, connect in parallel with the car battery, put a small suit in the cabin and a small reader, after a few seconds it is fully charged, then i close the switch. that's all.

very good, as of: 11/24/2019 simply use it in the car, connect it parallel to the car battery, put a small suit in the driver's cab and a small vol reader, in a few seconds it is full charged, then I close the switch. that's all.

These capacitors are poorly matched and self-discharge very quickly. The entire battery lost 4 volts in less than 24 hours. The worst of the group has lost over 1.5 volts and is always the first to start balancing.

Great price there is a ready made unit for $179 that does what it does. I bought it for $49, then added a waterproof case for $15, a switch for $10, I had a different cable and parts and built my own. This had a significant impact on the voltage swing damping on my truck which was having trouble turning the high load intake grille heaters on and off causing voltage sags and spikes. This has been removed. Highly recommend, I will be making a second unit for my RV inverter to improve its ability…

I bought this to use as a "battery booster" to start a dead battery car (in cold weather etc). It works well enough; With this capacitor bank I can start a car in parallel with a 5 year old battery. The capacitors aren't very well balanced though, ranging from 2.1v to 2.6v for a total voltage of 14.5v. It would also be nice if the capacitors were hot glued to reinforce the whole assembly; The board is quite flexible. Overall it does what I planned, if not quite what I was hoping for. I'll…

Update: Well that was too good to be true, as of today (2 days after the first review) I have 2 caps (#1 and #4) under 0 .5 charge volts in series , and a cap (#2) that is always 10mV over low, today it actually charged to 2.8V but luckily I caught that quickly and emptied the bank, the caps 3 , 5, 6 are all charged equally. I'm not sure if I have bad capacitors or a bad circuit board as there doesn't appear to be any equalization. When connecting a simple voltmeter, the voltage drops by 1 volt