Battery 'Stress' Reliever?

[JT646]

This is currently not practical for most of us...but might be the future for big battery setups:



Video shows a homemade capacitor bank added to a solar panel.

An electrician friend of mind said this would be VERY expensive (currently) to make...but would reduce high amp load/stress from a battery bank. His comment:    Think of big batteries as Kilowatt/hour storage....and big capicators as  Megawatt/seconds storage.  

Supposedly Tesla is considering capicator banks for future EV's....allows them to recover much more power from regenerative braking.

 

[StarliteRambler]

Capacitors can discharge all their stored power in an instant. Huge safety issue there..

 

[Wabbit]

Oh!... I guess I was wrong, I was expecting something else... Carry on.

 

[tx2sturgis]

Dang perverts....some of us anyway.

 

[optionsexplored]

Google "hard start kit" some companies selll them (Dometic maybe?) for their appliances, air conditioning units, etc.

It's just a capacitor. You could put one online for any high start up amp device if you wanted. But yes there are some safety considerations.

 

[Tom_M]

The topic is about storing 12 volt DC power, so it is no more dangerous than a 12 volt battery. A hard start kit does not store any power. It changes the voltage to current phase which will aid in starting an AC induction motor. A capacitor can not store AC power just as a battery can not store AC power.

 

[optionsexplored]

So why do they call them "hard start capacitors" as well? I swear they say it includes a capacitor.

 

[MrAlvinDude]

Sure, the original poster (OP) had a link to a DC storage system.  And those super capacitors can indeed lighten the load of supplying in-rush amps from a "slow" energy storage device, like a battery.

Enough super capacitors (in series and parallel) CAN indeed be the only energy storage, as shown in the video.

It can also be used (in parallel) combination with a battery, and it can lighten the start amp load on the battery, if there is a sudden/quick need for amps.
I believe the same youtuber has examples of this with his car-starter setup.


Now, the "hard start kit" that are offered to assist AC in-rush currents, are also still capacitors, but the way they are used are different from how a "battery" capacitor-bank is used.  
Because AC and DC work in different ways.  

Capacitors used in combination with AC voltage, typically store and release energy many times each second.
Where capacitors used in combination with DC voltage typically will store the energy for many, many consecutive seconds (or days) at a time.

For AC motors, I would say that the AC capacitors does some of their "magic", in combination with the coils in the motor. As the combination of AC, a capacitor and a coil has its own "magic" results.  
Well, it is currently magic to me anyway, but I know that it is a matter of some basic math to my engineering friends.


Here is for instance an example of how the right kind of capacitor, used in combination with AC power, limits the in-rush current of a motor:

Currently I have no idea if a "hard start kit" and a "soft start kit" (for an Air Conditioner) is actually just the same thing, but with two different names.


Now, using capacitors, in both the DC and AC setup method, might actually make life quite a bit smoother for the battery that is powering the entire setup and load.  As the short lived high amp needs are smoothed by the strategically placed capacitors.

 

[B and C]

Capacitors will release all their energy instantaneously if allowed. In the olden days before electronic ignition, there were points and a Condenser (capacitor) used to signal the coil to send a spark. The parts house guys used to charge one up and lay it on the counter to see who was dumb enough to pick it up. The ones that did not were deemed smart enough to know what they were talking about when ordering parts. If you picked it up, you got a nasty shock and everyone laughed. Be VERY CAREFUL around capacitors. These were very small capacitors. A large one could kill you.

 

[optionsexplored]

It sounds like you still need the capacitor for a soft start, but it uses some electrical voodoo to make the compressor ramp up nicer. I dunno, just posting what I'm reading. See my signature for details.

https://www.microair.net/products/start-capacitors-for-easystart-366

 

[tx2sturgis]

Ultracapacitors have been in use in industry and transportation for years...they are not really 'new'...

https://www.maxwell.com/products/ultracapacitors/modules

https://www.maxwell.com/solutions/transportation/heavy-transportation

.

 

[Tom_M]

Capacitors will release all their energy instantaneously if allowed.
This is also true of a battery.

 In the olden days before electronic ignition, there were points and a Condenser (capacitor) used to signal the coil to send a spark.
The condenser is there to prevent arcing of the points which would wear out the points rapidly. It does not send a signal.

 The parts house guys used to charge one up and lay it on the counter to see who was dumb enough to pick it up.  The ones that did not were deemed smart enough to know what they were talking about when ordering parts.  If you picked it up, you got a nasty shock and everyone laughed.  Be VERY CAREFUL around capacitors.  These were very small capacitors.
The capacitor was obviously charged to much more than 12 volts.

A large one could kill you.
If charged to 12 volts there is no more danger than a 12 volt battery.