capacitor bank

I guess this could work in a regular prius too not just a phev, but seemed like a good place to post it,
I was trying to wrap my head arround batery management systems and I came across capacitor banks wich are supposed to help with high loads, now I do not know enough about it but I thought that a capacitor bank could help recover more energy during regen braking and also take some beating so that the stock battery doesnt have to .
I know the stock batery runs at about 220v, and than there is an inverter that steps it up to 650v now in pure ev aplication there is also a moptor controller, I asume the prius has one too, the hybrid ecm they call it, questin is if one were to atempt such a capacitor bank, what size would it have to be and where would it go? the mg1 mg2 are ac motors if I am not mistaking and capacitors are dc, so it would have to be on the battery side I would say.
the 650v the inverter outputs I assume is ac, as well as the regen current comming from mg2, like I said I do not know enough so any thoughts?

 

thanks for stating the obvious, don't get me wrong I am not clueless but no where near knowledgeable, as for articles like wikipedia, there is nothing on there that I do not know about or that would provide a clue as to weather a capacitor bank is a feasable mod or a bad idea or rubbing a woden leg beating on a dead horse etc.
I was actually hoping somebody with somewhat experience would consider the thought and pitch in some ideas as to how to go about it and what to expect.
my experience with capacitors, I used to work with airconditioning units, and most compressors, even brand new ones wont start wihout one, rarely a fluke one may start but I never bother to try it they are built to use one, simply because there is not enough power in the supply to turn them 220v @30 amp, the capacitors on most had 3 terminals, comon run and start, some just a start, and even most fans would need one, I have seen them anywhere from 35mf to 5 mf.
I know they add up funny unlike batteries series is sum of 1/c, and most I worked with I believe they were rated for 370v
I know they take a charge very quickly and can discharge just as fast but they do not hold up much or for long for thet matter, further more there were jumppacks available if you have an old stuborned compressor that wont start in the spring one of those woul get it going again it would start thereafter till next spring eventually givving up.
I have read that in the prius especially at regen some large ammounts of amps are generated, theat is where I figured a cap bank could take the charge and either slowly bleed it into the batery or bounce right back at acceleration but that may get the computers all confused, may improve with efficiency, may even improve performance, may also blow something up.
so has anyone else ever considetred the thought?

 

that is kind of the input I was looking for, has anyone considered using common household/ industrial electric motors capacitors widely available and relatively cheap, than again I do not know what size of a pack one would need to build at least in theory therefore how many it would take, I searched for such a thread and came up empty, from what I remember your average AC compressor cap is 35 mf 370v, I have to go have a look at mine to confirm, these used to be a few bucks, a jumper ( as I mentioned previously used to get those older units going in the spring ) was about 15, I used to have shelves full of them at work, wonder how many it would take to build a pack, even 100 of them would be about 500 - 600 especially in large quantities, again not sure if those spec caps would even be feasable,
I'll try to find that thread

 

I have seen some built capacitor banks and they are huge I'll give you that, like I said I do not know enough, it's a thought that crossed my mind while looking up other phev stuff figured I'd bring it up, I haven't foud too much info as far as to what specs they are built, there is a you tube video looks like he has 10 of them and they are the size of a 2 liter, but not a whole lot of info as to specs or the batery pack it is in conjunction with, etc

 

I do not remember what a farad was, but I am pretty suer those common caps were rated ar 35 micro farads, 370volts, theyr role was it to give that motr an initial jolt, some of these motors were 220v with 30 amp fuses so do the math , the prius motor can take what something loke 650v at what amps?

 

I thought they would have a total different purpose, I had read that they can take a charge much larger and faster that a battery can just capacity is not much, so the idea was to use them as a buffer to take in the large amps from regen that the battery cannt handle or at least is what I thought they would do, I think that is the ideea in those racecars

 

I get that, and that's why the thought interested me, I figured some of the regen is getting dumped if you will because the batery can not handle it, a capacitor probably could

 

yeah good point, so B is for engine brake? it doesn't necesarily recover more energy in B, i did not know that, I guess the whole EV drivetrain would have to be built to incorporate a capacitor bank not just a simple upgrade

 

I came across that 100 amp number before and I think that was one of the issues with doing away with the hv battery in phev converssions, 40 ah lithium cells can't handle it, gues that's where the caps could come in,
I suppose the controler could pump more than 100 amps in some situations but that is probably getting complicated reprograming spooofing........... I get lost there