this post was submitted on 10 Jan 2025
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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
Physicists hate this one weird trick...