Check what I found in a drawer at work

[xlDooM]

4x 1000uF 40V capacitors



Did you know castle charges $21 for a PCB with 4 caps about the equivalent of 1 of these on it? Even if they have dried out somewhat, they'll have significant capacity left.

I'm going to solder it onto the battery leads of my $11 ebay ESC and hope that's enough to keep it somewhat cool. Without having really looked into it in detail, I believe voltage ripple is one of the reasons why ESCs burn up. I guess everytime you gun the throttle the battery voltage sags and the ESC caps have to provide a significant proportion of the current, and warm up as a result. If you have a capacitor bank outside of (but nearby) the ESC, it will take part of the blow (and therefore the heat) instead.

 

[X]

Not a bad idea. Luckily electrolytic caps can be relatively cheap. If those don't work out for you I could probably spec you something new. Though axial cans like you have are becoming harder to find in a any quality.

 

[xlDooM]

Indeed I was looking for new ones, cheapest I found for 1000uF 25V or more alu caps was 60 cents a pop, in a bag of 5, so it's really not that expensive. Shipping would probably take it close to $10. Not sure if this is something an electronics shop has on the shelf or not. We don't have radioshack over here...