6 ms·

All supercaps. Shorting a charged supercap is vastly more deleterious than shorting a battery or even a dc power supply.

finnh 10y ago
Deleterious or dangerous? (ie, does it hurt the supercap, or the thing shorting the supercap)? "When first I appear, I seem deleterious / But when explained, I'm nothing serious"
- lutorm 10y ago
  Probably both. The fraction of energy deposited in each depends on how the internal resistance of the cap compares to that of the load.
- deleted 10y ago
  [deleted]
- nerfhammer 10y ago
  Dangerous. Hurts the thing shorting the supercap and anything in close proximity to that thing
  - jhou2 10y ago
    wow, it sounds like it would make Samsung's Note 7 battery problems seem elementary. Who would want to carry a device like that in their back pocket or hand it to kids to play with? Would a good drop on hard pavement or sheet metal cause this thing to go off?
    - nerfhammer 10y ago
      It's not particularly easier to physically rupture than a normal battery. You would have to smash it hard enough to break apart the device.
Dylan16807 10y ago
Alternatively: All supercaps. They have vastly inferior energy density compared to a battery.
jonawesomegreen 10y ago
Shorting batteries is also never a great idea, but supercaps are more dangerous because of their low internal resistance. This video is a good demonstration: https://www.youtube.com/watch?v=EoWMF3VkI6U https://www.youtube.com/watch?v=EoWMF3VkI6U I was working on a controls project where we had large banks of supercaps that would charge up to ~900v. Have to treat those with some respect. However as long as they are kept cool the caps had no trouble being charged and discharged with a couple minute cycle with each bank providing 2kWh of energy. In the particular application I was working on we actually had 17 2kWh banks providing ~34kWh of energy every couple minutes. Would not fit in a cellphone though :)

finnh 10y ago

Deleterious or dangerous? (ie, does it hurt the supercap, or the thing shorting the supercap)? "When first I appear, I seem deleterious / But when explained, I'm nothing serious"

lutorm 10y ago
Probably both. The fraction of energy deposited in each depends on how the internal resistance of the cap compares to that of the load.
deleted 10y ago
[deleted]
nerfhammer 10y ago
Dangerous. Hurts the thing shorting the supercap and anything in close proximity to that thing
- jhou2 10y ago
  wow, it sounds like it would make Samsung's Note 7 battery problems seem elementary. Who would want to carry a device like that in their back pocket or hand it to kids to play with? Would a good drop on hard pavement or sheet metal cause this thing to go off?
  - nerfhammer 10y ago
    It's not particularly easier to physically rupture than a normal battery. You would have to smash it hard enough to break apart the device.

Dylan16807 10y ago

Alternatively: All supercaps. They have vastly inferior energy density compared to a battery.

jonawesomegreen 10y ago

Shorting batteries is also never a great idea, but supercaps are more dangerous because of their low internal resistance. This video is a good demonstration: https://www.youtube.com/watch?v=EoWMF3VkI6U https://www.youtube.com/watch?v=EoWMF3VkI6U I was working on a controls project where we had large banks of supercaps that would charge up to ~900v. Have to treat those with some respect. However as long as they are kept cool the caps had no trouble being charged and discharged with a couple minute cycle with each bank providing 2kWh of energy. In the particular application I was working on we actually had 17 2kWh banks providing ~34kWh of energy every couple minutes. Would not fit in a cellphone though :)