Questions tagged [capacity]
The capacity tag has no usage guidance.
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Capacity meter across deep-cycle lead-acid 24 V series with 12 V chargers [closed]
I've recently purchased a boat converted to use a 24 V trolling motor. Instead of one large 24 V battery it has four 6 V golf cart batteries in series to create 24 V. These are charged by a dual-bank ...
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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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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 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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Does an inverter only draw power from a battery as-needed?
In other words, does a 1000-watt inverter, draw the same as a 500-watt inverter if they are charging only a laptop? The laptop will draw the same amount and the inverter capacity is really just that, ...
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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 ...
CommunityBot
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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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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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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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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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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 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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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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What is the capacity of capacitors in this power supply circuit?
Imagine the following circuit with two capacitors and diodes acting as passive PFC.
My question is what is the capacity of these two capacitors? I mean compared to a circuit with just a single ...
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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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Calculate battery state of charge percentage
What is the correct formula to calculate battery state of charge percentage based on the battery type (12v, 24v, 48v and so on) and the current battery voltage.
For example if I have a 12v battery ...
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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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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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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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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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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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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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What does "capacity achieving code" mean?
I am an electrical engineer passed several courses in information theory and coding theory, however as I think now, I see that I have not understand the basic ideas in these concepts till now.
We ...
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how to understand the capacity in binary symetric channel (BSC)
According to the wiki about the BSC (binary symetric channel),
given the bit flip rate p,
the capacity is derived as :
H(p) = -p*log2(p) – (1-p)log2(1-p)
C = 1 - H(p).
the error probability p ...
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Optimal Capacity of Wireless Relaying
"Optimal approach to relaying occurs when transmission is recieved simultaneously at the destination and relay." Is this still valid in the light of recent research? Are there trade-offs involved?
...
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Relation between battery cell capacity & internal resistance
I'm trying to design a large battery pack, that should provide a given amount of power, with a reasonable amount of heat dissipations. To do so, I have three degrees of freedom:
indidividual cell ...
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Why do series combinations of Batteries not increase Capacity?
I've come to realize that batteries connected in series does not increase the capacity. But why is this so?
This question explains that it doesnt Adding mAh when wiring battery cells in series?,
but ...
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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 ...
