Internal Resistance of Average Car Battery: Discharge/Charge & Temperature Dependence

Hello. I think I chose the right department. I can't find this information anywhere. Namely:

What is the internal resistance of the average car battery? Discharged to zero and charged?

How much does it depend on the battery temperature?

Poor looking: http://www.fizykon.org/elektrycznosc/el_opor_wewnetrzny.htm
This is one of the many results from Google.

I don't see the answer to my question here.

After all, it can be measured very easily.

internal resistance of the source in this case, the battery should be as low as possible, strive for
zero, take zero practically at home, because you will not measure it

esperoaranos wrote:

Discharged to zero and charged?

Discharged to 0V or to 10.7V? If the voltage at the terminals = 0, it is a scrap and not a battery. The internal resistance will depend on the battery capacity, the higher the resistance, the lower the resistance. As a guide, the internal resistance of a fully charged battery is 3-10 m?

vodiczka wrote:

esperoaranos wrote:

Discharged to zero and charged?

Discharged to 0V or to 10.7V? If the voltage at the terminals = 0, it is a scrap and not a battery. The internal resistance will depend on the battery capacity, the higher the resistance, the lower the resistance. As a guide, the internal resistance of a charged battery is 30-100 m?

So when consuming only 30 A, the voltage drops by 3 V. Interesting? And what about starting, it goes down to minus 6V (for a small starter).

Aleksander_01 wrote:

vodiczka wrote:

esperoaranos wrote:

Discharged to zero and charged?

Discharged to 0V or to 10.7V? If the voltage at the terminals = 0, it is a scrap and not a battery. The internal resistance will depend on the battery capacity, the higher the resistance, the lower the resistance. As a guide, the internal resistance of a charged battery is 30-100 m?

So when consuming only 30 A, the voltage drops by 3 V. Interesting? And what about starting, it goes down to minus 6V (for a small starter).

I don't want to be malicious, but 1m? = 0.001?
You got something wrong with your calculations.

On average, the internal resistance of a lead-acid battery is:
10m? for capacities up to 20Ah, 5m? 20-50Ah, 2m? for 50-100Ah, 1m? for 100-240Ah, 0.5m? for 240-500Ah and 0.1m? for 500-1000Ah.
A used battery has this resistance at least about 2.5-3 times greater.

U = I * R. e.g. for 100Ah, the starter consumes 350A, so we have a voltage drop of around 0.35V.

krau wrote:

You got something wrong with your calculations.

Sorry, actually It should be 3-10 m?, I have already corrected.

vodiczka wrote:

The internal resistance will depend on the battery capacity, the higher the resistance, the lower the resistance.

AWESOME, where they taught or teach. I suggest a little bit of study.

Aleksander_01 wrote:

AWESOME, where they taught or teach. I suggest a little bit of study.

SHOW you how they taught you, I'd like to read what can you accuse my statement? Probably only that I did not indicate that I compare batteries made in exactly the same technology and not any batteries.

Since the battery capacity is related to its internal resistance We write about acid batteries. From a battery, e.g. 50 Ah, you can easily get a battery with a much larger capacity by removing its plates from the housing and immersing it in a much larger amount of acid solution. But his resistance wen. will not change.
Internal resistance acid battery depends only on the surface of the plates, and the capacity on the amount of acid solution.

There are 12 V 50 Ah batteries on the market with a starting current of about 1000 A, to achieve this the cells are rolled (surface). There are 1.5 V batteries on the market with the inscription HEVY DUTY - used for toys, motor drives where electricity is required, and LONG LIFE batteries - "long life" used for watches, remote controls, etc.

I'm not malicious, but seeing someone writing such stupid things is .......... it's a pity to write.

Aleksander_01 wrote:

Internal resistance acid battery depends only on the surface of the plates, and the capacity on the amount of acid solution

Only now have YOU GIVEN BODIES, it's funny when you give up writing nonsense and write them yourself. :D

Where do you think the battery stores its energy? Write the equation of the chemical reactions occurring on the electrodes during the charging and discharging of the battery and you will understand what nonsense you were doing :cry:

And do not confuse the relationship between the capacity and the internal resistance of the battery with the relationship between the inrush current and the internal resistance of two batteries of the same capacity.

But you girls are scratching ...

The capacity and impedance of the battery depend on many factors, but the surface of the claddings (and this may be larger than the surface that is the product of the length and width, because the structure of the cladding is spatial) is of the greatest importance here - generally batteries with a larger capacity have lower impedances and are able to deliver larger current (and thus have less "internal resistance").

As it was written earlier in the thread - you can indirectly calculate it from the starting current provided by the manufacturer (according to the manufacturer's conditions, i.e. current expenditure with an acceptable voltage drop).

deus.ex.machina wrote:

But you girls are scratching ...

But gender

deus.ex.machina wrote:

The capacity and impedance of the battery depend on many factors, the surface of the claddings (which may be larger than the product of the length and width, because the cladding structure is spatial) is of the greatest importance.

Right, only the surface of the cladding cannot "be larger" but "it is always larger". The times when the active surface area of the electrodes was approximately equal to the product of dimensions are long gone.

One could further discuss, but write Vodiczka technically and not "The times when the active surface of the electrodes was equal to the product of dimensions are long gone." Write down how it is done today in acid or similar batteries.

Compare such aku
http://allegro.pl/akumulator-volt-zap-sznajder-12v-100ah-760a-i4046543323.html
http://allegro.pl/akumulator-optima-red-rtc4-2-12v-50ah-swiezy-2013r-i4111564687.html

The questioner asked a fairly simple question - how to calculate the internal resistance. the battery in question.
For this, all you need is a resistor, ammeter and voltmeter, and an internal resistance. any voltage source is computable having these three things.

Aleksander_01 wrote:

The questioner asked a fairly simple question - how to calculate internal resistance given the battery.

You are stubborn and you distort everything in your own way, the questioner asked:

esperoaranos wrote:

How much is internal resistance average car battery?

Aleksander_01 wrote:

Write down how it is done today in acid or similar batteries.

I am not going to lecture to someone who thinks that the capacity of the battery does not depend on the surface of the electrodes but on the amount of acid:

Aleksander_01 wrote:

Internal resistance lead acid battery depends only from the surface of the plates, and the capacity depends on the amount of acid solution .

The internal resistance also depends on other factors, e.g. the gap between the electrodes.
deus.ex.machina he wrote correctly: "The capacity and impedance of the battery depends on many factors, with the surface of the cladding being the most important factor here"

vodiczka wrote:

Right, only the surface of the cladding cannot "be larger" but "it is always larger". The times when the active surface area of the electrodes was approximately equal to the product of dimensions are long gone.

It depends on the purpose of the battery - sometimes the spatial structure is not significantly expanded, e.g. for the sake of battery longevity - a lot could be written about it.

Aleksander_01 wrote:

The questioner asked a fairly simple question - how to calculate the internal resistance. the battery in question.
For this, all you need is a resistor, ammeter and voltmeter, and an internal resistance. any voltage source is computable having these three things.

I dare say that the matter is a bit more complicated - yes, you can use the technical method using two different resistors to try to determine the impedance of the battery, but the problem itself is much more complex because to determine the actual impedance you would have to take into account the dynamics of the physicochemical processes taking place in the battery, which is a bit more complex than the treatment of the battery as a static current source.
As I already wrote - for working use, you can use the starting current specified by the manufacturer, which usually determines the safe from the battery point of view, the duty cycle, the actual battery impedance will usually be even lower, but "using" it may mean irreversible damage to the battery.

deus.ex.machina wrote:

It depends on the purpose of the battery - sometimes the spatial structure is not significantly expanded, e.g. for the sake of battery longevity

You are right again, but this topic applies to car batteries, and in them there has been a long-standing tendency to increase the capacity and inrush current without increasing the dimensions and weight of the battery, which can only be achieved by expanding the active surface of the electrodes and their tighter packing. The result - the battery is less long-lived than a dozen years ago and, what's worse, it can fall unexpectedly, without signaling its near end by the resistant turning of the starter.