capacitors for rc car question.

[Jstagzsr]

id ont know where else to turn so i always end up back on LTT hoping someone knows whats going on.. sorry if this isnt the place..


I recently bought a new rc car. Arrma Typhon 6s.. i am using two 3S 5200mah 60C lipos. it is very snowy here in NY so ive only got a chance to run the car once for about 5 minutes. when i got inside i noticed that my batteries were warm. which leads me to believe either the 150amp esc is asking for too much power from my batteries (35c+ recommended), or the spikes in power from the brushless system are too harsh on the battery.. either way, i want to build a capacitor bank to run in the car.. i know everything there is to know about doing this besides the most important part, what capacitors to use... i have a sh!t load of capacitors laying around in cases from taking apart old electronics and recycling the parts to be used in other projects in the future (like this).. all the forums and posts ive read and all the products ive tried to reverse engineer in my head still havent given me the answers im looking for.. i know im gonna need a high uf count. i have 100uf, 460uf, 1uf, .5uf, etc.. and each of those varying uf capacitors all have varying volts... and thats the question im wondering about.. the forums ive read peopel are using 50v capacitors.. but my 6s lipo is only like 25 volts.. i know i need to accomodate for the spikes, but double seems a bit crazy.. wouldnt plugging a 50v capacitor into my esc immediately fry it? seeing how its not meant to take more than 6s (arguable 8s).. and if it is the case that the capacitors will only discharge what is being asked of them and the 50v is only the ceiling of what it can do, then could i just run a couple 450v 1000uf capacitors? or 200v 100uf? also, seeing how my total power from the battery is only going to be 25 volts roughly, does that mean the capacitors can only charge to 25 volts? and is that why the voltage of the capacitors doesnt matter? and if the capacitors can only charge to the amount of what the battery outputs, wouldnt it make sense to use the two massive capacitors like the 450v 1000uf ones so i therefore would only really be using 25v 2000uf of the capacitors and therefore putting negligible stress on the capacitors? and that way eliminating any heat they would other wise build up if i was maxing them out?

[Biomecanoid]

7 minutes ago, Jstagzsr said:

id ont know where else to turn so i always end up back on LTT hoping someone knows whats going on.. sorry if this isnt the place..


I recently bought a new rc car. Arrma Typhon 6s.. i am using two 3S 5200mah 60C lipos. it is very snowy here in NY so ive only got a chance to run the car once for about 5 minutes. when i got inside i noticed that my batteries were warm. which leads me to believe either the 150amp esc is asking for too much power from my batteries (35c+ recommended), or the spikes in power from the brushless system are too harsh on the battery.. either way, i want to build a capacitor bank to run in the car.. i know everything there is to know about doing this besides the most important part, what capacitors to use... i have a sh!t load of capacitors laying around in cases from taking apart old electronics and recycling the parts to be used in other projects in the future (like this).. all the forums and posts ive read and all the products ive tried to reverse engineer in my head still havent given me the answers im looking for.. i know im gonna need a high uf count. i have 100uf, 460uf, 1uf, .5uf, etc.. and each of those varying uf capacitors all have varying volts... and thats the question im wondering about.. the forums ive read peopel are using 50v capacitors.. but my 6s lipo is only like 25 volts.. i know i need to accomodate for the spikes, but double seems a bit crazy.. wouldnt plugging a 50v capacitor into my esc immediately fry it? seeing how its not meant to take more than 6s (arguable 8s).. and if it is the case that the capacitors will only discharge what is being asked of them and the 50v is only the ceiling of what it can do, then could i just run a couple 450v 1000uf capacitors? or 200v 100uf? also, seeing how my total power from the battery is only going to be 25 volts roughly, does that mean the capacitors can only charge to 25 volts? and is that why the voltage of the capacitors doesnt matter? and if the capacitors can only charge to the amount of what the battery outputs, wouldnt it make sense to use the two massive capacitors like the 450v 1000uf ones so i therefore would only really be using 25v 2000uf of the capacitors and therefore putting negligible stress on the capacitors? and that way eliminating any heat they would other wise build up if i was maxing them out?

If you think your batteries are getting too hot then you need higher C rating batteries, higher discharge batteries NOT capacitors.

[Jstagzsr]

3 minutes ago, Biomecanoid said:

If you think your batteries are getting too hot then you need higher C rating batteries, higher discharge batteries NOT capacitors.

i said they were warm, not hot. i havent ran it long enough to know if they get any warmer. and if the recommended discharge rating is 35c and up, and mine are almost double the recommended rating, i assume the discharge rating isnt the issue.

[BuckGup]

The capacitor thing will be a large waste of time and reliability will not be terrible. Lipos will get hot and swell under normal use. I don't think there is anything wrong with your setup. Also a 150A ESC doesn't mean it will always pull 150 amps. It is rated up to that which it mostly likely won't reacg since it's a prebuilt so they designed the components to be balanced. Capacitors aren't the same thing as a Lipo is, they aren't batteries.

[Jstagzsr]

1 minute ago, BuckGup said:

The capacitor thing will be a large waste of time and reliability will not be terrible. Lipos will get hot and swell under normal use. I don't think there is anything wrong with your setup. Also a 150A ESC doesn't mean it will always pull 150 amps. It is rated up to that which it mostly likely won't reacg since it's a prebuilt so they designed the components to be balanced. Capacitors aren't the same thing as a Lipo is, they aren't batteries.

im well aware of what capacitors are, and im well aware of why i want them in my system. in a brushless setup capacitors take stress off your battery. lipo batteries arent made to have power draw way up then way down then way up then way down then way up, etc. the "spikes" of power draw.. . when you install a capacitor bank on your esc the only thing your batteries have to do is supply the steady stream of undemanding power to the capacitors, and the capacitors which are made to extremely quickly dump power and charge up, all the stress that the brushless esc puts on the power system is drawn from the capacitors, eliminating the stress on the batteries.

[Biomecanoid]

3 minutes ago, Jstagzsr said:

i said they were warm, not hot. i havent ran it long enough to know if they get any warmer. and if the recommended discharge rating is 35c and up, and mine are almost double the recommended rating, i assume the discharge rating isnt the issue.

The higher the C rate the better for the battery. The battery does not get strained under load, does not get that warm, its less likely to swell, and it lives longer plus you can charge it faster.

[Jstagzsr]

Just now, Biomecanoid said:

The higher the C rate the better for the battery. The battery does not get strained under load, does not get that warm, its less likely to swell, and it lives longer plus you can charge it faster.

i am aware of this. this is why they give you a recommended C rating to use.. which mine is almost double of. the discharge rating is not the problem. 60c is more than sufficient. and lipo batteries arent supposed to swell AT ALL!! and if they ever do, i immediately dispose of them. healthy lipos dont heat up and dont swell at all.

[Biomecanoid]

1 minute ago, Jstagzsr said:

i am aware of this. this is why they give you a recommended C rating to use.. which mine is almost double of. the discharge rating is not the problem. 60c is more than sufficient. and lipo batteries arent supposed to swell AT ALL!! and if they ever do, i immediately dispose of them. healthy lipos dont heat up and dont swell at all.

If you are at double the recommended C rating you should be fine but if you notice swelling or batteries run super hot go up the C rating some more.

 

Also expo and dual rates on the controller help smooth hard acceleration and load spikes on the ESC, battery and gears

[nick name]

@Jumper118

[BuckGup]

40 minutes ago, Jstagzsr said:

im well aware of what capacitors are, and im well aware of why i want them in my system. in a brushless setup capacitors take stress off your battery. lipo batteries arent made to have power draw way up then way down then way up then way down then way up, etc. the "spikes" of power draw.. . when you install a capacitor bank on your esc the only thing your batteries have to do is supply the steady stream of undemanding power to the capacitors, and the capacitors which are made to extremely quickly dump power and charge up, all the stress that the brushless esc puts on the power system is drawn from the capacitors, eliminating the stress on the batteries.

 

38 minutes ago, Jstagzsr said:

i am aware of this. this is why they give you a recommended C rating to use.. which mine is almost double of. the discharge rating is not the problem. 60c is more than sufficient. and lipo batteries arent supposed to swell AT ALL!! and if they ever do, i immediately dispose of them. healthy lipos dont heat up and dont swell at all.

There is a difference from swelling under use and being puffed. If the battery stays inflated after it cools then you should dispose of it. Otherwise this is completely normal. As for the power draw it doesn't matter either. The largest factors to degrade a LiPo battery are charging rate, temperature, and discharge rate. If your C rating is ample for your setup,  you are charging at the recommended rate, and using a high LiPo cutoff. Your battery will last a long time. Also many ESCs already have these capacitors you talk about.

 

[Jstagzsr]

1 hour ago, BuckGup said:

 

There is a difference from swelling under use and being puffed. If the battery stays inflated after it cools then you should dispose of it. Otherwise this is completely normal. As for the power draw it doesn't matter either. The largest factors to degrade a LiPo battery are charging rate, temperature, and discharge rate. If your C rating is ample for your setup,  you are charging at the recommended rate, and using a high LiPo cutoff. Your battery will last a long time. Also many ESCs already have these capacitors you talk about.

 

agreed. on all counts. besides the swelling part. literally none of my lipos have ever swelled under normaL use. if they did i threw them out immediately. its only happened a few times but ive seen the damage lipos can cause. i may just be overly paranoid but id much rather be safe than sorry when it comes to lipo batteries. i definitely have seen people with swollen lipos that i wouldve been afraid to touch let alone use, and they were performing perfectly normal, but it still scares me to know i could not only burn my house down, or burn myself or someone else very very bad, but i could also lose my investments that i cant afford to replace (my cars).

and yes i also do acknowledge the capacitors on the esc already that do exactly what i am trying to accomplish, but i want something overkill to be perfectly honest. whatever my system requires from a capacitor, i would like to tripple or quadrupple that number. just for peace of mind's sake if nothing else.

but this leads back to initial questions, what specs am i looking for in a capacitor.. i am mainly trying to figure out the questions i asked about the voltages.

The info is definitely appreciated though.

[Jstagzsr]

1 hour ago, Biomecanoid said:

If you are at double the recommended C rating you should be fine but if you notice swelling or batteries run super hot go up the C rating some more.

 

Also expo and dual rates on the controller help smooth hard acceleration and load spikes on the ESC, battery and gears

i agree with that. but that kinda defeats the purpose of what im trying to accomplish. i want to be able to beat the piss out of the car and have it laugh and ask for more. lol. and im most likely perfectly fine as is, its just a peace of mind thing knowing i have a capacitor bank taking care of the high draw spikes when i full throttle it. i dont want to have to worry about whats going on under the hood. if that makes sense.

[Biomecanoid]

8 minutes ago, Jstagzsr said:

i agree with that. but that kinda defeats the purpose of what im trying to accomplish. i want to be able to beat the piss out of the car and have it laugh and ask for more. lol. and im most likely perfectly fine as is, its just a peace of mind thing knowing i have a capacitor bank taking care of the high draw spikes when i full throttle it. i dont want to have to worry about whats going on under the hood. if that makes sense.

If you worry about the battery just get 80c or 100c ones. You will strip the drive-train of break something before you wear the batteries out. You worry for the wrong thing you will have mechanical issues before you start having electrical/electronic issues.

You are trying to find a complicated solution for a problem that does not exist.

 

I don't think capacitors are the way to go and no-one has done that before. The only capacitors i know of in RC cars are the ones found on the ESC and the ones used as "Turbo" or "NOS" that you assign to a switch on your controller flip it and they give you a temporary boost.

 

Also adding capacitors on your power-line will probably add delay and your throttle response will lag.

 

 

[mariushm]

If you do decide to use capacitors, you will most likely need to use polymer or ultra low esr capacitors with high current ripple specs.... capacitors similar to the ones used on motherboards near the cpu socket.

The voltage rating has to be higher than the maximum voltage the batteries would ever output, but sometimes one goes for a capacitor that has a higher volume because higher volume means better specs (higher current handling, less internal resistance, more resistant to voltage spikes)

Probably would make sense to parallel some ceramic capacitors with the regular "bulk" capacitors.

 

[Jstagzsr]

30 minutes ago, Biomecanoid said:

If you worry about the battery just get 80c or 100c ones. You will strip the drive-train of break something before you wear the batteries out. You worry for the wrong thing you will have mechanical issues before you start having electrical/electronic issues.

You are trying to find a complicated solution for a problem that does not exist.

 

I don't think capacitors are the way to go and no-one has done that before. The only capacitors i know of in RC cars are the ones found on the ESC and the ones used as "Turbo" or "NOS" that you assign to a switch on your controller flip it and they give you a temporary boost.

 

Also adding capacitors on your power-line will probably add delay and your throttle response will lag.

 

 

it is an extremely popular option among high end rc's.. everyone knows that you add capacitors on your power line in between esc and battery for those quick powerful spikes of draw. most, if not ALL RC companies sell theri own "cap packs" that you you plug in to your battery to esc line to do the exact same thing that im trying to do.. i dont think youre understanding the concept of what it is im trying to do.. when you add capacitors to your system it completely eliminates the stress that is put on your battery from a brushless system.. brushless systems put huge stress on lipo batteries. lipo batteries are great for steady consistant powerful drain, but they are bad at sudden spikes in draw. the constant ups and downs in draw caused by the way brushless systems work is bad for any battery, regardless of the discharge rating.. even the highest end lipo batteries on earth are still no match for the quick discharge capabilities of a capacitor. brushless systems require a modulating power stream. lipos want to put out a steady stream. i dont know how else to explain it. you should look into it though because if youre into RC youre gonna get way way longer use out of your batteries and just have an overall healthier system with the use of capacitors.

and i have never heard of the "turbo" thing youre talking about but that doesnt make sense to me.. a capacitor is not an extra battery that adds to your power. theyre used to supplement the power stream during spikes and drops in power from the pwm signal that brushless systems use. and they discharge so fast that even if you could hook it up against what its designed for and use it as an aditional power source, what are you gonna get a .01 second boost? ive never heard of that and it doesnt make sense to me. im sure someone has done it somewhere but thats not what capacitors are made to do. i would be worried of exploding the capacitors or overheating them and melting down something in the system elsewhere because of the bad capacitor.

[Jstagzsr]

13 minutes ago, mariushm said:

If you do decide to use capacitors, you will most likely need to use polymer or ultra low esr capacitors with high current ripple specs.... capacitors similar to the ones used on motherboards near the cpu socket.

The voltage rating has to be higher than the maximum voltage the batteries would ever output, but sometimes one goes for a capacitor that has a higher volume because higher volume means better specs (higher current handling, less internal resistance, more resistant to voltage spikes)

Probably would make sense to parallel some ceramic capacitors with the regular "bulk" capacitors.

 

yeah absolutely. the only capacitors i have are pulled out of high end motherboards and power supplies and bords like that. and i dont have a way to test the esr of them but i agree that is definitely vital.

[BuckGup]

7 hours ago, Jstagzsr said:

agreed. on all counts. besides the swelling part. literally none of my lipos have ever swelled under normaL use. if they did i threw them out immediately. its only happened a few times but ive seen the damage lipos can cause. i may just be overly paranoid but id much rather be safe than sorry when it comes to lipo batteries. i definitely have seen people with swollen lipos that i wouldve been afraid to touch let alone use, and they were performing perfectly normal, but it still scares me to know i could not only burn my house down, or burn myself or someone else very very bad, but i could also lose my investments that i cant afford to replace (my cars).

and yes i also do acknowledge the capacitors on the esc already that do exactly what i am trying to accomplish, but i want something overkill to be perfectly honest. whatever my system requires from a capacitor, i would like to tripple or quadrupple that number. just for peace of mind's sake if nothing else.

but this leads back to initial questions, what specs am i looking for in a capacitor.. i am mainly trying to figure out the questions i asked about the voltages.

The info is definitely appreciated though.

You are definitely being paranoid about it. I would be more concerned strapping a ton of capacitors to my Lipos as now you have many more points of failure and shorting out. A Lipo is waterproof but adding a ton of capacitors, if not properly weather sealed, is asking for a short. LiPo fires are mostly due to punctures which puffing on a soft cell increases the pressure so it's easier to puncture. Otherwise lithium is a malleable metal 

[Biomecanoid]

10 hours ago, Jstagzsr said:

it is an extremely popular option among high end rc's.. everyone knows that you add capacitors on your power line in between esc and battery for those quick powerful spikes of draw. most, if not ALL RC companies sell theri own "cap packs" that you you plug in to your battery to esc line to do the exact same thing that im trying to do.. i dont think youre understanding the concept of what it is im trying to do.. when you add capacitors to your system it completely eliminates the stress that is put on your battery from a brushless system.. brushless systems put huge stress on lipo batteries. lipo batteries are great for steady consistant powerful drain, but they are bad at sudden spikes in draw. the constant ups and downs in draw caused by the way brushless systems work is bad for any battery, regardless of the discharge rating.. even the highest end lipo batteries on earth are still no match for the quick discharge capabilities of a capacitor. brushless systems require a modulating power stream. lipos want to put out a steady stream. i dont know how else to explain it. you should look into it though because if youre into RC youre gonna get way way longer use out of your batteries and just have an overall healthier system with the use of capacitors.

and i have never heard of the "turbo" thing youre talking about but that doesnt make sense to me.. a capacitor is not an extra battery that adds to your power. theyre used to supplement the power stream during spikes and drops in power from the pwm signal that brushless systems use. and they discharge so fast that even if you could hook it up against what its designed for and use it as an aditional power source, what are you gonna get a .01 second boost? ive never heard of that and it doesnt make sense to me. im sure someone has done it somewhere but thats not what capacitors are made to do. i would be worried of exploding the capacitors or overheating them and melting down something in the system elsewhere because of the bad capacitor.

I think your inventor mode is on overdrive. There is no need for capacitors, that is not the solution to your problem. No-one has done anything similar nor there is a relevant product on the market.

 

If there was a need for such a product, there would have been manufacturers from china making it. These guys make everything and anything

 

As i said before you will be breaking gears, differentials, A-arms, bumpers etc before your battery die. RC cars get mechanical issues 1st electronics are much more reliable.

 

If you want to beef up something get upgraded drive-train parts. It would be a shame to have a super battery+capacitor setup and not be able to run your RC because you stripped your gears.

 

 

 

 

[Jstagzsr]

41 minutes ago, Biomecanoid said:

I think your inventor mode is on overdrive. There is no need for capacitors, that is not the solution to your problem. No-one has done anything similar nor there is a relevant product on the market.

 

If there was a need for such a product, there would have been manufacturers from china making it. These guys make everything and anything

 

As i said before you will be breaking gears, differentials, A-arms, bumpers etc before your battery die. RC cars get mechanical issues 1st electronics are much more reliable.

 

If you want to beef up something get upgraded drive-train parts. It would be a shame to have a super battery+capacitor setup and not be able to run your RC because you stripped your gears.

 

 

 

 

omg dude.. literally 30 seconds of research would show you youre wrong. idk why youre arguing with me over something so easily proven. this is a very popular thing with high power rc cars. clearly you are either out of the loop or you dont own any high powered rc cars.
so, like i said, i suggest you do some research. literally EVERY major company has cap packs for sale. Youre arguing against easily proven facts.

i have a Arrma Typhon 6s. which can take up to an 8s. 150amp esc. 2200kv motor.  and the entire drivetrain is hardened steel. all my gears are hardened steel. and i have the stock Dboots tires, and some foamies for speed runs, and my main badlands set.. For bashing, this is just about as good as it gets. thats why i chose this platform as my base. theres always some upgrade that can be done, but i am satisfied with the setup.

https://www.ebay.com/itm/EM-PERFORMANCE-RC-CAP-PACK-Hobao-Mugen-Traxxas-Losi-Kyosho-Arrma-/272512958331

https://www.amazon.com/Castle-Creations-011-0002-02-Pack-Capacitor/dp/B0062GK06A

https://www.killmoderc.com/

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR2.TRC1.A0.H0.Xrc+cap+pack.TRS0&_nkw=rc+cap+pack&_sacat=0

[Biomecanoid]

 

 

 

 

 

15 hours ago, Jstagzsr said:

id ont know where else to turn so i always end up back on LTT hoping someone knows whats going on.. sorry if this isnt the place..


I recently bought a new rc car. Arrma Typhon 6s.. i am using two 3S 5200mah 60C lipos. it is very snowy here in NY so ive only got a chance to run the car once for about 5 minutes. when i got inside i noticed that my batteries were warm. which leads me to believe either the 150amp esc is asking for too much power from my batteries (35c+ recommended), or the spikes in power from the brushless system are too harsh on the battery.. either way, i want to build a capacitor bank to run in the car.. i know everything there is to know about doing this besides the most important part, what capacitors to use... i have a sh!t load of capacitors laying around in cases from taking apart old electronics and recycling the parts to be used in other projects in the future (like this).. all the forums and posts ive read and all the products ive tried to reverse engineer in my head still havent given me the answers im looking for.. i know im gonna need a high uf count. i have 100uf, 460uf, 1uf, .5uf, etc.. and each of those varying uf capacitors all have varying volts... and thats the question im wondering about.. the forums ive read peopel are using 50v capacitors.. but my 6s lipo is only like 25 volts.. i know i need to accomodate for the spikes, but double seems a bit crazy.. wouldnt plugging a 50v capacitor into my esc immediately fry it? seeing how its not meant to take more than 6s (arguable 8s).. and if it is the case that the capacitors will only discharge what is being asked of them and the 50v is only the ceiling of what it can do, then could i just run a couple 450v 1000uf capacitors? or 200v 100uf? also, seeing how my total power from the battery is only going to be 25 volts roughly, does that mean the capacitors can only charge to 25 volts? and is that why the voltage of the capacitors doesnt matter? and if the capacitors can only charge to the amount of what the battery outputs, wouldnt it make sense to use the two massive capacitors like the 450v 1000uf ones so i therefore would only really be using 25v 2000uf of the capacitors and therefore putting negligible stress on the capacitors? and that way eliminating any heat they would other wise build up if i was maxing them out?

*I know everything there is to know about doing this besides the most important part, what capacitors to use ...

If you don't know what capacitors to use then you don't know that much, or anything useful.

 

* it is very snowy here in NY so ive only got a chance to run the car once for about 5 minutes

LOL you can't even run your otherwise awesome Arrma Typhon because its snowing and you worry about battery temperatures?

.

Go waterproof your electronics so you can actually use your car in any weather and not have it as a self queen. I don't need to waterproof my cars because it never snows where i live but i do waterproof the electronics of my speedboats.

 

 

 

1 hour ago, Jstagzsr said:

omg dude.. literally 30 seconds of research would show you youre wrong. idk why youre arguing with me over something so easily proven. this is a very popular thing with high power rc cars. clearly you are either out of the loop or you dont own any high powered rc cars.

so, like i said, i suggest you do some research.

have a good one. i wont be replying to anymore of your comments.

*omg dude.. literally 30 seconds of research would show you youre wrong.

Well if its a 30sec research project why your need help and haven't finished already?

 

* so, like i said, i suggest you do some research.

Well i don't need to do any research for a fictional problem. My RC cars are running fine no issue with electronics or batteries and i made them myself.

 

* have a good one. i wont be replying to anymore of your comments.

Well go do your thing and be merry while doing it. Its not that i will be crying my heart out if you will not be replying  .

 

 

 

Your Arrma Typhon can do like 100mph so with that speed if you hit gravel, a pebble or a pothole the wrong way it will go flying thru the air and come crashing down. The batteries won't hinder you from having fun with your car broken parts WILL, so start stocking on parts that are more likely to break.

 

It seems that you have already set your mind on doing your capacitor mod so there is no point on asking people about it. Its like your are just looking for people to agree with your rather than gather opinions.

 

You are obsessing and you have your priorities mixed up. There are way more important issues you have to address and your "spectacular" capacitor fix for a virtually non existent issue is on the very bottom of the list.

 

 

 

 

 

 

 

 

[johnny5c]

On 1/23/2020 at 12:09 PM, Jstagzsr said:

 i know i need to accomodate for the spikes, but double seems a bit crazy.. wouldnt plugging a 50v capacitor into my esc immediately fry it? seeing how its not meant to take more than 6s (arguable 8s).. and if it is the case that the capacitors will only discharge what is being asked of them and the 50v is only the ceiling of what it can do, then could i just run a couple 450v 1000uf capacitors? or 200v 100uf? also, seeing how my total power from the battery is only going to be 25 volts roughly, does that mean the capacitors can only charge to 25 volts? and is that why the voltage of the capacitors doesnt matter? and if the capacitors can only charge to the amount of what the battery outputs, wouldnt it make sense to use the two massive capacitors like the 450v 1000uf ones so i therefore would only really be using 25v 2000uf of the capacitors and therefore putting negligible stress on the capacitors? and that way eliminating any heat they would other wise build up if i was maxing them out?

I had the same question when I added a Castle cap pack to my E-Revo's MXL-6s ESC.  The answer I got at R/C Universe was that the capacitors will only charge to the line voltage they're supplied with so the 50v capacitors will never charge higher than 22v when connected to two 3s packs.  The only warning I got was to make sure it was fully discharged before installing if it had been used before with a higher voltage system.  And FWIMC capacitor packs are a well known thing in the hobby grade R/C world.

 

But nice setup you have there, was considering a Kraton bur ended up getting a X-Maxx instead.

[Matacks]

Nice.  I really like arrma RCs.  They are really the hot thing thats out right now.  I've been eyeing one of the buggies.  The speed of these RCs is ridiculous.   

 

Concerning your lipos it's entirely normal for lipo batteries to warm up or even get a little hot during use..    the main thing to look out for is never discharging below 3.3v per cell during running.  The esc has a built in low voltage cutoff to try to prevent this but careless running down your batteries can puff the lipos.   Also never charge a hot battery.  It has to cool first.    I would say it's unnecessary to hook up a capacitor battery system but I have seen some crazy speed runner guys hook up such crazy things.   They are very experienced though and not so concerned about ruining their toys.  The way I've seen it used is to give the esc a crazy high amperage boost kinda like a nitrous shot but even then it can make the RC impossible to control and it just sorta takes off like an airplane.    Often times they get free stuff to make YouTube videos and such..   it's not something I'd ever need to try.  Getting an RC to hit 100 mph is sorta serious business and a lofty goal for any hobby enthusiast.  Be careful friend. 

[meenmeen1103]

I've built several impractical speed run cars. Things like 1/10 touring and 1/16 micro on 4s lipo, and a slash 4x4 on 6s.

First I'll agree that the theory of cap packs has been explained in the thread already: stores excess power when system is not under load, and can more quickly release stored power than the batteries in said system.

 

However, the scope to which this is actually helpful hasn't been explained or argued much. The battery temps increase when under load specifically because of their internal resistance, which IS used to determine C rating but: C ratings are about as accurate as CPU TDP ratings when you consider them as a whole in the industry (not taking shots at specific brands) . They shouldn't be used as an exact basis.

 

Now, practicality: they don't store anywhere near enough power for long term. A capacitance of 1 Farad (1 million uF's) can hold 1 amp for 1 second. In systems rated over 100 amps, cap packs, which are definitely not anywhere near 1 Farad, can only ever help on startup power i.e. take-off burst power, 'burst' meaning microseconds.

 

The reason cap packs from known brands even exist is because they are cheap af to manufacture, and marked up substantially to a market that looks for any and every possible advantage for their setups, this also ignores the marketing behind them. Oh, and laziness. I would say some people just can't solder for various reasons and these products being pre-built helps but soldering caps of this size to a board is no more difficult than soldering the leads, which you will definitely have to do anyway. 

 

This is absolutely no solution to helping batteries run cooler, but it's a passion driven hobby so if you want to give them a try, just pick low ESR (again, internal resistance is the biggest factor) and try to ignore any placebo for a validated answer yourself!

Edited January 29, 2020 by meenmeen1103
broke up paragraph for reading-friendliness

[Jstagzsr]

On 1/26/2020 at 5:32 AM, johnny5c said:

I had the same question when I added a Castle cap pack to my E-Revo's MXL-6s ESC.  The answer I got at R/C Universe was that the capacitors will only charge to the line voltage they're supplied with so the 50v capacitors will never charge higher than 22v when connected to two 3s packs.  The only warning I got was to make sure it was fully discharged before installing if it had been used before with a higher voltage system.  And FWIMC capacitor packs are a well known thing in the hobby grade R/C world.

 

But nice setup you have there, was considering a Kraton bur ended up getting a X-Maxx instead.

awesome dude. thank you. i was starting to want to bang my head against a wall talking to other people. lmao. i wish i wouldve checked my notifications here sooner. thank you for the help. that was the main question i wanted answered!!!!

#TeamArrma

[Jstagzsr]

On 1/28/2020 at 11:22 PM, Matacks said:

Nice.  I really like arrma RCs.  They are really the hot thing thats out right now.  I've been eyeing one of the buggies.  The speed of these RCs is ridiculous.   

 

Concerning your lipos it's entirely normal for lipo batteries to warm up or even get a little hot during use..    the main thing to look out for is never discharging below 3.3v per cell during running.  The esc has a built in low voltage cutoff to try to prevent this but careless running down your batteries can puff the lipos.   Also never charge a hot battery.  It has to cool first.    I would say it's unnecessary to hook up a capacitor battery system but I have seen some crazy speed runner guys hook up such crazy things.   They are very experienced though and not so concerned about ruining their toys.  The way I've seen it used is to give the esc a crazy high amperage boost kinda like a nitrous shot but even then it can make the RC impossible to control and it just sorta takes off like an airplane.    Often times they get free stuff to make YouTube videos and such..   it's not something I'd ever need to try.  Getting an RC to hit 100 mph is sorta serious business and a lofty goal for any hobby enthusiast.  Be careful friend. 

thank you man. much appreciated.