Questions tagged [capacity]
The capacity tag has no usage guidance.
144 questions
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Resistance vs Capacity in Building a Power Bank
I am building a power bank consisting of "12" 18650 cells arranged as 3 set of 4 in parallel and then putting the 3 sets in series to achieve 12.6 V more or less.
My questions are:
do I ...
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How is capacity fade calculated?
https://www.ipaceforums.co.uk/threads/capacity-fade-vs-power-fade.6794/
According to this post capacity fade is defined as the percentage of total capacity left. So I'm assuming it would be calculated ...
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Theoretical equation to describe capacity fade
https://www.researchgate.net/publication/357842717_How_do_Depth_of_Discharge_C-rate_and_Calendar_Age_Affect_Capacity_Retention_Impedance_Growth_the_Electrodes_and_the_Electrolyte_in_Li-Ion_Cells
I am ...
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How to calculate the capacity from a given list of currents,RelativeTime and Time which are obtained through experiment?
I'm working on machine Learning Project to build a model that predicts Remaining useful life time of a battery using NASA dataset which consists data of four 18650 batteries (identified as RW9,RW10,...
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TP4056 charge discharge for a NiMH prius battery?
I want to make a capacity tester for a 6 cell module for prius batteries. They have 6000mAh new and anywhere from 2500-5000 mAH used. I was wondering if theTP4056 would work for a NiMH battery and if ...
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Lithium polymer battery size versus energy density
I am building a small device that needs to use a rechargeable lithium polymer battery. The dimensions I am looking for are 351125 { 35 mm (H) x 11 mm (W) x 25 mm (L) }, which is the standard way these ...
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Lithium-ion battery 36V, 10Ah in electrical scooter
Battery lithium 36V, 10Ah is running for 9 hours with no load on the motor (with 0.5 A draining) which gives us 4.5 Ah, and for 2 minutes with load on motor (with 17 A draining). If we consider 4.5 Ah ...
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What components will I require to ascertain the capacity of a lithium iron battery?
I see quite a few posts on measuring battery capacity. However, I cannot find one that shows how this is practically achieved (if there is a post, kindly inform me).
I am assuming in order to ...
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Battery monitoring for voltage, current and capacity
I have a 12V 7Ah and 12V 18Ah lithium-ion battery at home. I want to be able to monitor the battery's voltage, current, and capacity.
I came across this IC from TI, BQ26621, however I then noticed ...
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Can an MN27 alkaline battery power my 12 V, 0.16 A motor?
I have two motors in parallel rated for 12 V at 0.16 A.
They generate a small 14.4 pounds (64 N) of force combined at a slow speed of 30 mm/s.
The motors open and close a door for this project.
The ...
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RTE schematic diagram for battery with a load
I am trying to draw a schematic to get information for battery round trip efficiency. My equipment is:
1 x 5 kW battery
1 x 48 VDC power supply
1 x 48 VDC load (const current)
1 x DC shunt
1 x ...
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Why are life cycles used as a measure for battery health?
I was curious on how the depth of discharge for batteries affects the battery health as I've heard never to let your phone go down to 0%.
I was searching online and every paper I found on this topic ...
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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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651
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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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321
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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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81
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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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66
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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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643
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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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280
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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 ...