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On August 27, 2019, @xeexee wrote:
Plx in an experiment to determine the internal resistance of a cell, why is it that a cell should not be kept assembled for a long time??
On March 5, 2019, Mechatronix wrote:
Dear community, as it is commonly done, calculate the inner resistance (direct current method in discharge direction) as following: DCIR=dV/dI=(Vnoload-Vunderload) / (Iunderload-Inoload) whereas I at noload is normally zero, but also two load levels can be used for this test. The SoC is percentage value of Energy (Wh), normally, you can get out of the Battery. The max. Wh value depends on manufactures definition, the energy amount he allows you to suck out of the battery (limited by max an min voltage specification. Some device manufacturers might deviate from this definition, to give you good feeling when having a look to your cell phone SoC.. br & take care
On January 29, 2019, DASARI jOSHI wrote:
Dear Sir, Of-course you have given to all of us a great knowledge in and through this notes. Thanks and Regards.
On January 29, 2019, Anand wrote:
How to calculate internal resistance of 12V 35AH lead acid battery. What are the parameters we need to consider while calculating the resistance.
On July 1, 2018, phil w wrote:
Mr L: no battery has an internal resistance of zero. A bit of copper wire doesn't have zero resistance. Even superconductors don't have zero resistance - the have tiny resistance.
On June 27, 2018, Mr. Lam wrote:
I have measured the internal resistance using a internal resistance meter and I found when a battery is new the internal resistance is always zero. After sometimes of usage it will go up to more than 1 ohm. When it is more than 1 ohm it is time to replace the battery. It apply to all kind of battery. Usually I due with 12vdc lead acid battery and Lithium battery. Is it true? The internal resistance must not more than 1 ohm using a internal resistance meter to measure. Is it true?
On April 20, 2018, phil w wrote:
Walter S - If the flashlight has any kind of regulating circuit - a buck-regulator for instance the brightness is set by the regulator's current setting. An any battery chosen would not affect the brightness. If it has no regulator then Alkaline batteries would give a brighter output. This is due to their having around 1.5V open circuit whereas NiMh has 1.2V per cell.
On April 20, 2018, phil w wrote:
There's an equation for calculating battery condition "Peukert's" equation - based on his law. To properly measure charge in and out you would need an arduino running such an equation so time and current could be integrated. To do this you need a low ohm precision shunt resistor for measuring the current. Internal resistance is only really of general interest when considering max current draw. I ran into a banana-skin using electronic flash kit. I tried NiMH. These are semi useless despite their claimed capacity giving very long re-cycling times. After research I resorted to NiCd which, for the Sanyo/Panasonic Cadnica AA, a minimal value for a new battery is claimed to be 15mOhms at 50% discharge. These really can deliver monster current and thus make the flash re-cycling times 1 or 2 seconds as opposed to the 10s of NiMh. Watch-it though, if the circuit was designed in view of NiMH and high IR then putting NiCd may overload the tansistors controlling the current so killing the device. Yes folks, Nicads are nasty polluting technology so I shall be careful as to how I dispose of then when their days are over.
On January 14, 2018, Walter Saucier wrote:
Which AA will make my LCD flashlight shine brighter - eneloop Pro, standard eneloop 2000 mAh, or other NIMH AA? Does one have lower internal resistance than the others?
On July 3, 2017, Mayank Vyas wrote:
Hello Sir, 1.How to determine the diffusion rate and its after effects using EIS? 2. Is it possible to use EIS to determine the fault diagnosis of a battery ONLINE?
On May 15, 2017, Catalin Vladareanu wrote:
Hello to every one, The internal resistance can be an indicator of the state of health of the battery (SOH) ? What are relation between those. Many thanks. BR
On February 8, 2017, DaBigDude wrote:
What is considered high IR and what is considered low IR. I have a rack full of AA. Some have IR of 40, some have IR of 600+. At what point are the batteries effectively done and to be tossed/recycled? They all still charge. Some last longer than others in use.
On January 5, 2017, SUNIL CHAUHAN wrote:
SIR PLEASE TELL ME THAT HOW MUCH INTERNAL RESITANCE FOR 100 AMPR. BATTERY OF SELENIUM ALLOY THANKS
On December 3, 2016, Abhijeet Saxena wrote:
This article doesn't include the internal resistance of the Lithium Ion cells with age, i.e., with number of discharge cycles. I think that is also a big factor in comparing the different types of batteries. It would be better if that is also included.
On June 2, 2016, Archie Goldswain wrote:
I recover used 12volt car batteries and recharge them using dhc smart chargers, I find that seemingly good batteries measuring higher than 10.5v take charge up to 75% but doesn't top out at 100% where after the temperature rises and the battery is permanently lost. Intarnal resistance measures "Hi" or "Low" indicating the values are out or range. Please advise.
On December 30, 2015, Ted Brown wrote:
I am measuring the internal resistance of a marine deep cycle 12 v battery. I want to know when is the resistance too high. I know a new battery is measuring about 4.5 m ohoms
On October 14, 2015, Jake Willis wrote:
Yeh, id just like to say thanks again for the help. I've spent the whole class sitting on tinder trying to organise a slam pig for this evening. Peace out, Jakey
On October 14, 2015, Jake Willis wrote:
Cheers for helping me for 2b m8. eternally grateful, your m8 Jake
On September 30, 2015, Aminos wrote:
Hi every one, how can I estimate the internal resistance from some measured results such as voltage, current temperature.........is there any relationship between those parameters. Thanks
On July 24, 2015, Angus wrote:
Please tell me how many number of internal resistance is standard of a new battery? For example: 12V 60Ah car battery.
On July 8, 2015, Sanjay wrote:
How to calculate IR of 12 volt ok battery Example :- 12 Volt 130 AH SMF Battery
On November 23, 2014, dave backer wrote:
well, i think that there are many other things who affect performance, and they should be taken under consideration, <a href="https://thegreencard4u.com/green-card-lottery/">green card lottery</a> .
On August 21, 2014, YeonWoo Kim wrote:
hello. I'm interested in Battery. I have currious that how to look for State of Charge(SOC). Could you please let me know a mathematical formula of SOC. Thank you.
On March 24, 2014, Rob David wrote:
I am flying my 450 helicopter with a set of 6 2.2A 3 cell 11.1V 30C Lipo Battery Packs which I monitor as carefully as possible. Post every flight I measure output voltage, IR of each cell, internal temperature and then I measure these same parameters pre and post charge. This possibly seems a bit of an overkill but I am able to carefully see if any trends are occurring in any of my battery packs and I believe I have saved my helicopter exactly for this reason as one of my pack failed as I was spooling up the motor - as expected according to my recorded parameters. I was expecting this failure because the one pack's IR different between the 3 cells was getting progressively further apart and progressively more. IR for the 3 new cells started of at 4,4,1 failed at 18,15,12. Knowing perilously little about battery electronics, I saw this as a sign of pending failure and I was, possibly by coincidence, correct. But here is the real question. If this parameter is as important as I think it is, How much difference between the 3 cells is too much? I am currently getting concerned when the max and minimum cell are 50% of each other. Is this too much or too little or am I barking up the totally incorrect tree here?
On February 25, 2014, Thegraj Govindasamy wrote:
Hi All Please assist with the following related to flooded lead acid batteries; 1) Can an internal resistance test detemine state of charge of the battery. 2) Is it still necessary to do a Specific Gravity reading if the above confirms this? 3) What's the relation between internal resistance tests and specific gravity tests. REGARDS THEGRAJ GOVINDASAMY
On December 17, 2012, gaurav wrote:
how internal impedence calculation is better than self dicharge voltage ?
On November 6, 2012, Claudius Mudefi wrote:
hi guys, mine is not a comment but honestly i want to know if there is any advantage of a battery having a higher value of internal resistance.
On October 9, 2011, Roberlanio Melo wrote:
Gentlemen, what was the method used to measure the internal resistance of cell phone batteries?
On June 10, 2011, Antonio Sarasua wrote:
Hello, is anybody here? please i need to know the full reference of Shukla et al. 1998. Rodrigues et al. 1999. THANKS!
On February 25, 2011, Ingo Kitzmann wrote:
Can you please provide me with a state-of-charge curve for a typical lithium-ion manganese cell, maybe discharged at 0.2C, 1C and 2C, with the voltage both measured under these discharge conditions, and as open terminal voltage. If there is such a curve available: Is the open terminal voltage a reliable measure for the state of charge?
On January 28, 2011, M.Nouman Ansari wrote:
Wonderfull Web I never saw before ,with full information Thanks
On December 3, 2010, Antonio Sarasua wrote:
Hello, where can I find the Rerences: Shukla et al. 1998. Rodrigues et al. 1999? Tahnks a lot in advance
Figure 1: Effects of internal battery resistance.
High resistance causes the battery to heat up and the voltage to drop. The equipment cuts off, leaving energy behind.
Internal resistance provides useful information in detecting problems and indicating when a battery should be replaced. However, resistance alone does not provide a linear correlation to the battery's capacity. The increase of cell resistance only relates to ageing and provides some failure indications.Why is internal resistance important? ›
Internal resistance is one of the parameters that indicate a battery's ability to carry current. When the value of internal resistance is low, the battery is able to carry a significant amount of current. On the other hand, a battery with high internal resistance can only carry a small amount of current.Does internal resistance affect power? ›
The effect of the internal resistance is that the voltage supplied by the power supply drops as the current drawn from the power supply is increased. It also determines the maximum current that can be drawn from the supply.What affects internal resistance? ›
In practice, the internal resistance of a battery is dependent on its size, state of charge, chemical properties, age, temperature, and the discharge current.What is meant by internal resistance? ›
Internal resistance refers to the opposition to the flow of current offered by the cells and batteries themselves resulting in the generation of heat. Internal resistance is measured in Ohms. The relationship between internal resistance (r) and emf (e) of cell s given by. e = I (r + R)How the performance of the plug in power supply would be affected if its internal resistance were reduced? ›
The internal resistance is used to explain changes in the terminal voltage when the current in a circuit varies. The lower the internal resistance of a given power supply, the more current it can supply while maintaining a nearly-constant terminal voltage.Why does internal resistance increase with time? ›
The metal particles absorb hydrogen during charging and desorb during discharging. The electrolyte slowly corrodes the metal particles, increasing the dead layer at the surface of the grain, which makes it harder for the hydrogen ions to get to and from the metal, increasing the resistance.What is low internal resistance? ›
One of the urgent requirements of a battery for digital applications is low internal resistance. Measured in milliohms, the internal resistance is the gatekeeper that, to a large extent, determines the runtime. The lower the resistance, the less restriction the battery encounters in delivering the needed power spikes.What happens when internal resistance is negligible? ›
What is 'negligible internal resistance'? This expression often appears in exam questions. It doesn't mean the resistance has to be small per se. It simply means that the battery isn't being made to work hard enough for its voltage to drop much.
I've searched around and here's all that I could find on "ideal" internal resistance measurements. Quote: Based on my online research, combined with my own experience and findings, I would say, as a general rule, a per cell rating of between 0-6 mΩ is as good as it gets. Between 7 and 12 mΩ is reasonable.How does resistance cause power loss? ›
Any resistor in a circuit that has a voltage drop across it dissipates electrical power. This electrical power is converted into heat energy hence all resistors have a power rating. This is the maximum power that can be dissipated from the resistor without it burning out.Why do we ignore internal resistance? ›
While analyzing a circuit, the internal resistance of EMF sources is ignored. ... When there is no potential difference in the circuit, then no current will flow.Does internal resistance increase voltage? ›
As current decreasesd, voltage across the internal resistance of the cell, Ir, decreased (using V=IR), because internal resistance should remain constant. Therefore voltage across the terminals increased (as less is wasted across the internal resistor).How does internal resistance affect battery? ›
The lower the internal resistance, the better the battery performance is. The higher internal resistance in a battery, the more the battery will heat up creating a voltage drop.What is the difference between resistance and internal resistance? ›
What is the difference between resistance and internal resistance?Which is not affected by internal resistance? ›
Which is not affected by internal resistance?Which are the two factors that influence resistance? ›
Which are the two factors that influence resistance?How do you find internal resistance? ›
How do you find internal resistance?Can a good circuit have internal resistance? ›
Can a good circuit have internal resistance?
Does internal resistance act in open circuit?How is the output power of a device affected by the high internal resistance of a battery? ›
How is the output power of a device affected by the high internal resistance of a battery?How much internal resistance should a battery have? ›
How much internal resistance should a battery have?What is the internal resistance of a car battery? ›
What is the internal resistance of a car battery?What is the relationship between current and internal resistance? ›
What is the relationship between current and internal resistance?How do you increase the internal resistance of a circuit? ›
How do you increase the internal resistance of a circuit?Does internal resistance increase with age? ›
Does internal resistance increase with age?Which of the following has a high internal resistance? ›
Which of the following has a high internal resistance?What happens to EMF when internal resistance increases? ›
What happens to EMF when internal resistance increases?How does internal resistance of a cell affect the amount of current it generates? ›
How does internal resistance of a cell affect the amount of current it generates?
Can the internal resistance of a battery be negative?What is a good IR for LiPo? ›
What is a good IR for LiPo?What is a good IR for a LiPo battery? ›
What is a good IR for a LiPo battery?What is high IR on LiPo? ›
What is high IR on LiPo?Does higher resistance mean more power? ›
Does higher resistance mean more power?Does less resistance mean more efficient? ›
Does less resistance mean more efficient?Does higher resistance reduce power? ›
Does higher resistance reduce power?Why does voltage decrease when internal resistance increases? ›
The voltage decreases because of the increasing current through the internal resistance.Why does the internal resistance of a battery increase with use? ›
As the battery is discharged the electrolyte concentration is reduced, becoming pure water when the battery is fully discharged. Because of this change in electrolyte concentration the battery resistance increases during discharge. Loss of electrolyte is also a frequent cause of increased electrolyte resistance.How do you increase the internal resistance of a circuit? ›
The internal resistance of an electrical source depends on the distance between the two electrodes. It also depends upon the internal area of the electrical source. Hence, the internal resistance can be increased by increasing the length between the electrodes and by decreasing the area of the electrical source.
Even if the cell is not connected in a circuit, electrons /ions travel inside the electrolyte. A dry cell always has some internal resistance. Because of this internal resistance there is always some voltage drop associated with the cell even if the cell is not being use, and eventually become dead after a long time.What is the relationship between current and internal resistance? ›
What is the relationship between current and internal resistance?How does internal resistance affect battery? ›
How does internal resistance affect battery?What happens to voltage if resistance decreases? ›
What happens to voltage if resistance decreases?How the performance of the plug in power supply would be affected if its internal resistance were reduced? ›
How the performance of the plug in power supply would be affected if its internal resistance were reduced?What is IR value of battery? ›
What is IR value of battery?How much resistance should a 12V battery have? ›
How much resistance should a 12V battery have?How does resistance cause power loss? ›
How does resistance cause power loss?What is the effect of the internal resistance on the external potential difference? ›
What is the effect of the internal resistance on the external potential difference?What does high resistance mean? ›
What does high resistance mean?
What are the effects of internal resistance in the terminal characteristics of source?What effect does increasing the internal resistance of the source have on the load circuit? ›
What effect does increasing the internal resistance of the source have on the load circuit?Is internal resistance a drawback of the cell? ›
Is internal resistance a drawback of the cell?