Questions tagged [capacity]
The capacity tag has no usage guidance.
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Two 14S Lithium-Ion batteries have different charging speeds: the smallest is slower than the higher capacity one
Long story short: I built one 14S battery last year, using Molicell P42A cells. 6 cells in parallel for every series. So, around 58.8V total voltage on the battery.
Recently I made another battery ...
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Determine capacity of batteries for solar installation
I have four 420 Ah 6 volt batteries wired in series and then parallel.
What is the capacity of the combined four?
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18650 capacity tester opamp voltages on inputs different
I assembled an 18650 Li-Ion capacity tester with an Arduino Pro Mini.
Here is the schematic:
When I set the discharging current to 100 mA in the code (which means there has to be 100mV on pin 3 of ...
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How do you measure capacity without a constant current? (coulomb counting?)
What would be the most accurate (but not too expensive) method to find the capacity of NiMH battery cells when you are not able to use a constant current? Would using coulomb counting work or is that ...
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How does mixing wire sizes affect voltage drop over distance?
I am installing a well pump. The pump is single phase 240 V, 12.3 amps and has a soft start. Supply voltage from the Mfg: 1 x 200-240 V –10%/+6%, 50/60 Hz.
It's 200 feet (61 m) from the panel to the ...
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Calculating battery run time
How long will a 12 V, 35 Ah battery powering a 5 V, 1 A device last? Yes, there is a 12-5 V converter in this circuit.
Is the correct method for finding the solution to convert both sources to watts ...
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Nominal voltage of supercap
Is it possible to replace a supercap e.g. an FCS0V224ZFTBR24 which is a 3.5 V type by its equivalent with a higher voltage (5.5 V), the FCS0H224ZFTBR24? The datasheet of both types is here.
What will ...
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Battery capacity evaluation
To measure NiMH battery capacity, everything I've read so far indicates that in order to get an accurate evaluation you have to measure the discharge parameters.
I can understand that, however in my ...
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Question on NiMH battery circuit configurations
How do you calculate the total capacity (mAh) of batteries with unequal capacity when connected in parallel? Is it just simply the sum total of the capacities, or something else, like 4 times the ...
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Calculate duty cycle of device's on and sleep state to drain coin cell in given amount of time
I am trying to drain a 25 mAh ECR1216 coin cell in 2 days. My device draws 6 mA when on, and about 15 μA when on standby.
I am having a hard time determining a duty cycle for on/standby time to drain ...
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UPS vs portable power station capacity ratings
I have been looking to buy a dedicated 220V AC offline UPS or portable power station with an offline UPS functionality. What surprised me is that, whereas both are very similar devices, is that ...
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How to measure channel capacity performance for enhanced speech samples in GSM speech coders?
I've been conducting some research lately on Speech Enhancement of the ITU-T Recommended G.729 Voice Activity Detection (VAD) algorithm for GSM Speech coders.
It has been suggested in the literature ...
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Wouldn't charging a lithium battery to 80% only defeat the purpose of putting the battery into longer use in the first place?
I see most smart devices (laptops/tablets/phones) now have the option to optimize your battery by charging it to 80% only.
But wouldn't this reduce your capacity i.e. your brand new battery now only ...
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Why do I hear hissing sounds when I discharge my sealed lead acid batteries at high currents?
I've been doing some discharge tests in order to figure out the Peukert exponents of two sealed lead acid batteries with capacities 7 and 9 Ah, in addition to an initial current of 2.1 and 2.7 A, ...
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Presence of bandwidth in capacity formula
I'm looking two papers https://ieeexplore.ieee.org/abstract/document/9370130 and https://ieeexplore.ieee.org/abstract/document/8855846.
In the first paper, achievable rate is
w_n is bandwidth. p_n is ...
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Measuring capacitance of two wires [closed]
I have made a capacitor as follows:
I cut two straight wires of diameter 0.52 mm and length of 29 cm and separation width of s=2.5 cm.
I stuck them on a piece of neon to keep them fixed.
Here is the ...
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RMS or average current in battery lifetime
For the purpose of estimating the lifetime of a battery which supplies an irregular load (the current waveform is more or less arbitrary series of pulses - Bluetooth radio). The current is a pulsating,...
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Bandwidth distance product
A fundamental principle of communications states that for any given transmission medium, bandwidth-length product is constant. I know that optical fibers, for example, are used for high data rate ...
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Maximum bit rate over a communication channel
Shannon formula C= B log (1+S/N)
Is this formula applied for baseband transmission only? or for both baseband and passband modulation? Can we apply it without any changes to any modulated signal? What ...
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What is the capacity of this battery (details in the body)
Can someone give me the capacity (in Ah) for this battery?
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How do I increase the current a battery delivers? [closed]
Let's say there's a 2Ah battery with a C rating of 2C. So this means that I could discharge 4 amperes for half an hour at best.
Now, there is a default current that we get from a battery right? How ...
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Battery capacity in mWh instead of mAh [duplicate]
I know that the capacity of a battery is expressed in mAh, i.e. A/s (international system of units). Today I used a command in PowerShell (*) in order to get the battery capacity, but the unit of ...
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How to swap 3 AAA batteries for a rechargeable battery with a charging module [closed]
I have this table lamp that uses 3 AAA batteries to function, but the batteries run out pretty fast, so I'd like to swap them for a rechargeable battery that I can plug into a USB charger without ...
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Impact of Bandwidth Increase on Shannon Capacity
What is the impact of doubling of bandwidth on Shannon Capacity, assuming noise power spectral density and signal power remain the same?
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Can I connect batteries of different capacity in parallel?
I don't think this has been covered in other posts.
I have a 3.7V 6000mAh li battery pack and three 3.7V 2000mAh li battery packs. If I wire the three 2000s in parallel to make a 6000mAh cell, then ...
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Node voltage increases in voltage divider
I am planning to use a voltage divider in order to measure the capacity of a group of lithium batteries; in order to minimize power consumption, I biased a common-emitter switch (Q1) with the ...
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How to find capacity of a battery in terms of mAh or Ah?
I know that this question has been asked a number of times and even received negative feedback but I want to find a shortcut method of determining capacity of a battery in terms of mAh instead of ...
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Why the does channel capacity not increase as the number of subcarriers increases?
We usually consider multi-carrier (interchangeably multi-channel) communications.
By using the multi-carrier system, instead of one-broadband system, we can obtain many advantages, for example, able ...
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I need to power a device that requires 12V and 0.43A, with as small of a battery as possible
Basically, I have a device that MUST be powered by battery and it requires according to the item description an operating voltage of 12V and 0.43 Amperes. There are small batteries (A23 batteries) ...
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how to determine the Remaining useful life of lithium battery given charging discharging voltage, load, temperature of different cycles?
given 3 datas
1st-dataset contains charging details with fields:Voltage_measured,Current_measured,Temperature_measured,Current_charge,Voltage_charge,Time.
2nd-dataset contains discharging details with ...
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Determine a known battery's instantaneous capacity through voltage? / voltage's relation to capacity
Is it possible to approximate a battery's current (the "right now" kind of current) capacity, given its absolute capacity and a voltage measurement?
An example:
I have a 1s 260mAh LiPo that ...
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If a Li-Ion cell has 3000mAh capacity shouldn't I be able to pull 3A from it for 1 hour?
I have these brand new Li-Ion cells that are rated for 3000mAh and I'm trying to get their actual capacity. I have a discharger and its max current it can draw is 2A. However when I set that and run ...
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What is the derivation of the Shannon-Hartley theorem? [closed]
I know by Hartley's theorem that information is proportional to bandwidth and time. The capacity corresponds to information and bandwidth is there. I don't get how the logarithmic part corresponds to ...
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Measuring capacitance of Metal-Insulator-Semiconductor (MIS) structure with LCR meter
I can not get my head around what a LCR meter measures. My LCR meter measures my device (MIS) which is displayed as C_p and G_p (other components can be neglected). My LCR meter displays C_p, G_p, the ...
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Capacitive distance sensor - humidity influence?
We are using a capacitive sensor to measure displacement (from here: https://www.micro-epsilon.com/displacement-position-sensors/capacitive-sensor/?sLang=en). However, we seem to notice a significant ...
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Is a VL3030 coin cell battery a suitable replacement for a ML2430?
I am attempting to replace a battery in my electronic compass and im supposed to use an ML2430, however this is proving to be hard to get hold of and expensive.
I'm concidering using a VL 3032/HF5N ...
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Measuring the capacity of a 40v lithium ion, lawnmower battery
I purchased a 40v Greenworks lawnmower battery, and it's listed capacity (6,000 mah) doesn't seem to be accurate based on what I'd expect to get out of it when mowing a lawn.
How would you go about ...
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Can I replace an original laptop battery with an OEM battery with higher voltage / power?
My original laptop battery is 11.1 V and 74 Wh. It was starting to swell and needed replacement, but I accidentally bought a wrong OEM battery that is 11.4 V and 71 Wh.
Is it safe to proceed and use ...
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Difference between capacity and output current rating [duplicate]
I'm linking to this example, but all battery packs i see on Ebay and Aliexpress are like this.
https://www.ebay.com/itm/4800-20000mAh-Rechargeable-Portable-Power-Li-ion-Battery-DC-12V-For-Camera-PVD/...
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Same mAh, same volt - different current
I need to replace the 18650 battery of one application. The battery doesn't have any marking about volts, mAh or amperes.
Because it's 18650, the voltage is fixed - done. mAh - will use 2000mAh (let'...
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How long will my x 2 23a 12v battery last running a 300mah camera?
I’ve brought some WiFi cameras to run in bird boxes but the battery life on them aren’t very good at all.
I’ve tried running them from battery power banks but they switch off after the cameras have ...
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Preservation of power when wiring batteries in series - battery life is reduced if load is kept the same
This is really just a "sanity check" type question. Am I correct that if you place two batteries in series, that the battery life is effectively halved relative to just one battery, assuming the load ...
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Solar battery draining too fast
I have a Bosch L5077 180 Ah, 12 V deep-cycle sealed Pb battery for my solar setup. I bought it recently (two weeks ago) but since the weather was rainy the last two weeks, and the solar panels didn't ...
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Is it normal to have 40% capacity after 1.5 years of charging Li-Ion? [closed]
I have a laptop computer that spends 99% of its time plugged in. The last time prior to today I used the computer not plugged in was 1.5 years ago.
Today morning, I put the computer to sleep (with ...
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Is there a reason why lower voltage batteries are preferred for high AH?
I was looking at these batteries and considering whether to use a 12V battery or multiple 2V batteries for backup power. In any case, I came across this battery by Exide Tech - GNB Flooded Classic H1T ...
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18650 pack building - is it better to have similar batch or similar capacity?
I'm gonna build battery packs. I have quite a lot of experience with 18650 Li-ion cells, but there's one thing I still don't know.
I will buy CCA 100 new cells from seller (for example LGEBHE21865). ...
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Wire capacity - Total power or just current?
So I've gotten myself into a healthy, educational Facebook discussion. Link is here if you're a member of that group.
When I thought about it, everyone defines wire capacity by current only. The ...
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How to calculate remaining battery capacity from charge discharge data?
If a dataset contains data collected over time from a re-chargeable battery and includes information such as voltage, current, average discharge rate and peak discharge rates.
how can the remaining ...
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Usability of a deeply discharged Li-ion batteries
I have a question about Li-ion batteries.
About three years back I bought two Sony VTC 5 batteries for my vape. They are rated as 2500 mAh 30 A.
But I quit smoking about a year ago and I left these ...
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MW of installed capacity
I am conducting research on wind turbines, specifically into how many hectares wind farms use.
I have come across the phase 'installed capacity'. If wind farms typically use up 10 hectares per ...
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