All u did was decrease the life span of power bank
this post was submitted on 10 Jan 2025
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I nearly did this by accident a few nights ago. I was worried I almost killed it.
Most banks can't charge and discharge at the same time.
If they did, worst case it heats up as it moves the energy around until it runs out due to losses or blows up.
Nothing that can go wrong really.
...or blows up.
Nothing that can go wrong really.
hmmm
Yeah, that's actually worse than I thought it might be, lol
Battery pack loopback test successful...
No you shorted your battery
I'm pretty sure both directions are regulated, and the only reason it went up is some slight change in the voltage reading due to temperature or somesuch. All that I believe will happen here is that the battery, due to generating a bit of heat, will discharge itself at a safe rate.
I'm not sure though
the power output and the charging input are both regulated and (almost certainly) current limited. So I think (not positive...) that you're basically dissipating your power in the inefficiency the charging and output circuits, with this power coming from the battery.
The inefficiency should (I think...) just be the round-trip inefficiency of the charging/discharging of your power bank
this should be way, way less than the short-circuit power dissipation.
The simplest toy model is to take a battery and try to charge itself. So you put jumpers on the + terminal and you connect those to the + terminal, and same for - (charging is + to +, NOT + to -). But this is silly because you've just attached a loop of wire to your terminals, which is equivalent to doing nothing. With charging circuits in between things get much more complicated, but I'm not sure if it goes full catastrophic short...
I think you're right and I was just memeing, but I'm curious how the battery percentage went up
I guess that running power in a circle like that as fast as possible might heat up the battery, which reduces internal resistance, which increases battery voltage during load, which tricks the sensor that uses voltage to estimate charge.
It similar to when a fully charged but very cold car battery cannot start a car, as if the battery was discharged. Then you turn on the cars lights for a while, which to the cold batter is a significant load. The battery heats up, and then you can start the car.
I think the charge controller counts the amount of energy that has passed through it.
You're probably mostly correct. Some of them do literally count that, but (to my knowledge) most measure voltage as a battery with lower charge usually outputs less and vice versa.
My guess is it didn't, and the numbers were pulled out the OP's ass.
Otherwise, idk how power banks monitor their percentage of charge, but being that it's a percentage, if you fuck up the capacity, the same amount of energy will take up a higher percentage of that capacity. /shrug
I'm curious how the battery percentage went up
Physicists hate this one weird trick...
In this house we obey the laws of thermodynamics!!
Does burning down your own house count as science? Give this guy a medal!
Is that true though? As in, is it really that dangerous? It seems that you'll dissipate power equal to the inefficiency times the nominal charging power, so something like 5V x 2A x inefficiency (inefficiency being 1-efficiency), which will probably be of order a watt.
I can use my car battery to charge itself without any issues
I just plug the red terminal to itself, and same with the black, which is to say, a battery is always connected in a way that "charges itself."
I think the key is that the battery probably isn't really playing a big role in OOP's setup
electricity doesn't "go through the battery," it just goes from the charging input to the power output circuits, with the additional power (due to inefficiency) being provided by the battery.
No anymore, but if you destroy it in some more interesting way...
Just informed to the Nobel comittee.
Yea just gotta bring it on a plane and strap a coundown timer to it that makes loud beeping sounds
Rip BMS
My heart can't take it anymore