Comment on New breakthrough may let us charge smartphones in 60 seconds
Umbrias@beehaw.org 3 months agoAlmost every electrical system on the planet uses capacitors. Especially high power systems. Of which evs are.
“No real point in mixing capacitors in with a large battery” ?? That’s done literally all the time for both filtering and for intermittent high power output. Like when I say almost every electrical system uses caps, I mean almost every electrical system.
sonori@beehaw.org 3 months ago
Obviously nearly every electrical circuit board uses capacitors in some respect, especially for filtering and smoothing, but it is extremely rare for them to be used for bulk energy storage outside of things like adjusting power factor.
Given we are talking about charging times, which are primarily limited by the batteries charge current vs degradation curve and not at all by the various small capacitors in the charger’s electronics, there is fundamentally no effect on charge times unless you are replacing the energy storage medium itself with supercapacitors.
We can already supply enough dc power to charge an EV battery at its maximum designed curve via dc fast charging stations, which involve some contractors and shunts but actually don’t even involve any size of capacitors at all in the car itself on the HV side.
Umbrias@beehaw.org 3 months ago
Or you know, reducing thermal load by using broadly more efficient capacitors allowing you to shove more current in the car. Or by meeting grid scale requirements for car charging by smoothing out the grid impact of a bunch of charging at once. Or any number of benefits.
Ultimately this certainly benefits car charging. It benefits all electronics. No you won’t be getting two second car charges with this.
sonori@beehaw.org 3 months ago
Again, there are no capacitors car side to be produceing thermal load in the first place during dc fast charging in the first place, and that thermal load is not the primary barrier to how much current can go into the battery without degradation anyway. After all, if it was we would just upscale the cars heat pump and be charged in five minutes.
Car charging is not coordinated to the point where they all plug in within a few seconds, and if it was a few second randomizer on when eqch timer actually starts charging would accomplish the exact same effect without hundreds of millions to billions of dollars in new grid scale capacitors and inverters.
This is also unlikely to become a significant problem because a lot of the grid is moving to battery backed solar and wind, where the limit is price per megawatt hour and as such said batteries can provide far more current than the grid could consume. You might be limited by inverter capacity, but storage capacitors are also fundamentally a DC technology so you would need them anyway.
This may turn out to have benefits for electronics that rely on already specialized supercapacitors, but it can by definition not have any impact on processes that are not currently limited in any way by capacitor technology like battery bulk charge current, the thing that actually limits how fast a car can fast charge.
Umbrias@beehaw.org 3 months ago
At this point I can only determine you are arguing for the sake of arguing.