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The Battery at what state of discharge.
What resistor value would you expect to pass 25mA with 9V across it? BIG HINT: R=V/I
And who suggested internal resistance made the battery discharge?
I said a battery can be visualized as a perfect source with a series resistance, what makes you think a series resistance drains current? In my world, a series resistance limits current.
You have been told that some of its chemicals have been used up.I just don't understand how a brand new battery has a very low internal resistance but how does the internal resistance raise in value to get larger? what makes it grow in size?
YOU DO NOT UNDERSTAND!!A brand new battery has no discharge because the internal resistance is low but when the battery has a high value internal resistance there is a discharge?
NO!When a battery has a low internal resistance, there is no discharge
When a battery internal resistance raises in value , there is discharge
We have told you many times to use a typical load on a throw-away battery so you do not kill it and measure its voltage.How do you measure the state of discharge? do you measure the voltage or the current? does it make a difference?
You look on its datasheet. The Duracell alkaline 9V battery with a 50mA load current is almost dead when its voltage measures about 6.6V and it is half used up when its voltage measures about 7.5V.But how do you know what state of discharge the battery is at when you do measure the voltage and current?
The curves on the datasheet show the state of discharge and Ohm's Law can be used to calculate the internal resistance.Which you know the battery is discharging from a load, but how do u know what state of the discharge the battery is in and how do u know what the internal resistance is at what value?
We have told you many times to use a typical load on a throw-away battery so you do not kill it and measure its voltage.
On a rechargeable battery you can measure its maximum current then re-charge it.
When the battery is discharging then some of its chemicals get used up. Then its internal resistance becomes high.
The internal resistance is in series with the battery creating a voltage divider with the load resistance.
Its load is parallel to the output of the battery but is in series with the internal resistance.
Correct.so what you guys are saying is that a "Non-Rechargeable Battery" you can't measure the maximum current because it will kill it or use up all the chemicals?
Because of the chemical reaction slowing down when most of the chemicals are used up.Why does the internal resistance becomes HIGH when the chemicals get used up?
You still don't understand that the internal resistance is in series with the battery and the load forms a voltage divider that reduces the voltage at the junction of the resistors. Without a load the internal resistance is MUCH lower than the resistance of the meter so you measure the full voltage of the battery.when you measure the voltage of the battery it's still measures 9 volts without a load
Don't be silly. I showed you the datasheet for a Duracell 9V alkaline battery that says its internal resistance is 1.7 ohms when new.When you SHORT the battery terminals together, the voltage will measure ZERO volts, but the current is at the max. because the ESR internal series resistance is converting the battery voltage into a current
"maybe up" is bad English.This internal series resistance is maybe up of chemicals or charges
You do not understand electronics and chemistry and "discharge".Why does the internal series resistance get larger in value when the chemicals get used up? or there is discharge?
the shorted current is 9V/1.7 ohms= 5.3A for less than 2 seconds then the battery is dead. 9V x 5.3A= 47.7w so the battery will begin getting very hot.
Because of the chemical reaction slowing down when most of the chemicals are used up.
Of course not. Only a brand new Duracell 9V ALKALINE battery. The cheap Chinese ones in The Dollar Store are probably a few years old and use obsolete carbon-zinc chemicals. They might be able to produce 100mA if they do not leak too much "beer".So every 9 volt battery in general outputs 5 to 6 Amps of current?
Learn chemistry to find out why.So slowing down chemical reaction cause the internal resistance to get larger in value? i still don't get as to why
Yes.Internal resistance gets larger in value
1.) Chemical reaction slowing down
2.) Chemical being used up
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