Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [state-of-charge]

9 questions
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Can you monitor the state of charge of lead-acid batteries through their terminal voltage if they're being used?

Lead-acid batteries have -approximately- linear discharge curves and are therefore more easily monitored through their open-circuit voltage. Is there a way to monitor their SoC without disconnecting them from the circuit? (For example, when they…
A.H.Z
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At what charge of a battery should its internal resistance be calculated?

I am trying to determine a battery's internal resistance using the open circuit voltage, terminal voltage, and load current for each battery cycle. As per my current understanding, these calculations must be conducted at a particular charge of the…
Noor
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SLA battery under load: Is the absolute voltage or the state of charge primary for wear avoidance?

When an SLA battery is under load, they say not to go below a certain value to avoid wear. So, don't go under 30% State of Charge (SoC), which is also a certain Open Circuit Voltage (Voc), say 11.8V . So, here both values are linked, one value means…
e-motiv
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How does a lead acid battery accept more current when it is discharged than when it is charged if the resistance is higher when it is discharged?

I'm just trying to get my head around the above question. It doesn't seem to follow Ohm's law. Could someone please explain what I am missing in this? Below is a chart I found of the changing resistance of a lead acid battery compared to state of…
TMax
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what is the best design choice for making an ACCURATE solar battery monitoring system?

I plan on making a high accuracy solar battery monitoring system where I keep track of the voltage of two 12 V batteries in series (using voltage dividers) and the load current in order to determine the state of charge and the overall health of the…
A.H.Z
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How to calibrate coulomb counter using the open circuit voltage method? (Estimating battery state of charge)

According to u/Krexington_III answer from Reddit, to estimate battery state of charge in a mobile device, such as a cell phone, and do it pretty accurately (and without a need of heavy stuff like a neural network) device needs to use 2 methods -…
Wiktor Tomanek
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How to protect Li-ion cells from over-discharge when drawing high current?

I would like to throttle the power output of an LED light when the battery level is getting low. My initial approach was to measure the voltage and start throttling at about 3.7 V (which in my estimation is 20% left). However, drawing high current…
Yuriy Kulikov
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Is battery charge efficiency related to its self-discharge?

I've read a couple of research papers and technical user manuals concerning SOC estimation, all of which mentioned both charge efficiency and Self-discharge but did not mention whether these effects are related: charge efficiency is affected by…
A.H.Z
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Is there a relativily simple way to determine state of charge (SoC) for LiFePO4 batteries?

I'm searching for information regarding this matter and I can only find academic papers. I am wondering if anyone knows of any (more accurate or less accurate) way to evaluate the state of charge for batteries with LifePo4 chemistry. Prefer…
user733606
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