Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [battery-operated]

Involving or pertaining to a circuit or device that is intended to be operated with cells or batteries (as opposed to mains power, for example).

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Why do smoke detectors run off 9v batteries?

Is there a component that requires a higher voltage? Wouldn't they last longer on AA/AAA batteries?
Ryan Detzel
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battery lifetime with self discharge

I want to calculate the lifetime of a battery operated device. Without self discharge of the battery, it is easy to calculate the lifetime, it's just the battery capacity \$Q\$ (given in mAh) divided by the average current \$I\$ (given in mA). In…
Rick
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What size portable battery do I need?

I need to power a 10 W device to operate 16 hours a day on a 50% use capacity. So 10 W device running 8 hours a day I guess. I need to run this device from a battery pack as no AC is available. How many days can I run on what size of battery? Ideal…
Marty Lax
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Powering nichrome wire from battery

I'm looking to power nichrome wire from a battery. The problem I ran into is that desired length/width of the wire has very small resistance of ~ 8 Ω. Several kinds of batteries I've tested have internal resistance much higher than that, which leads…
Marcin Raczkowski
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Electrifying a Battery Operated Clock

I have a motion clock that runs off of two C cell batteries. One battery runs the movement at 1.5 volts. That other battery then continues in series to run the motion part delivering 3 volts to it. I would like to use a 3 volt dc plug in power…
Jim Ondracek
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Estimate current draw for battery replacement

Trying to revive an old electronic keyboard. It is labelled to take 9-12V and I have an appropriate connector, but don't have an idea of how much current to allow for. It can also be powered by 6 D cells, and presuming that they should last for…
sdg
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Should I connect battery ground to the metal enclosure

I'm aware in the automotive world the chassis of the vehicle is used as the return path to the battery negative however I am building an electric-powered cart running on 48V lithium batteries. The batteries come pre-built within a plastic enclosure…
Matt Roberts
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Using a modified non-proprietary battery for CPAP

My apologies if this isn't the correct place for this question. I am not familiar enough with some of these concepts to move forward on this without bouncing the ideas off of some more experienced people. I have this CPAP (medical device for…
coconuts
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Boat Auxiliary battery - this simple ok?

I have feared running out of battery voltage to start the boat engine after running the electronics with the engine off. Would something as simple as this figure work? Obviously both are 12V. Main is deep cycle lead acid and aux battery would be…
n c
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specific application of 9V battery pack substituted for a 9V power supply

I have a JamMan Solo XT loop pedal that is rated at 9V DC, 200mA. I want to make a really simple altoid tin battery pack. I'm checking with you guys because I don't want to damage the foot pedal with incompetence. So if Pmax occurs at R1 = Rload,…
chazalex
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Low current solution to standby power for battery powered electronics

Say I have a 12 V battery powered device, with a logic and control board that take 5V sourced from the 12V supply, what is the solution to powering up the device from standby while not unnecessarily draining the battery while in standby? I expect I…
J Collins
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LiPo battery powering low power MCU

I have an "ultra-low-power" MCU STM32L011F4. According to the specs its powering voltage range is from 1.65 V to 3.6 V. I want to power it with a LiPo battery with nominal voltage of 3.7 V. Which is slightly larger. But according to the table of…
Teivaz
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Where can I get informations about smartphones battery datasheet?

I'm hardly trying to find the datasheets and I still got nothing :(, what I was try to find is like Asus battery for Zenfone 4 Model: C11P1404 datasheet. Please for your kindness tell me where can I find that one :)
user251691
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Battery bank paralleling

Sir's/ madam, Is it possible to make a parallel comnection of 110V DC battery bank which are about 4 kms apart from each others. How to calculate the voltage drop and size of cable in between. Thanks. Pls. help.
NedupT
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I have a solar powered keyboard

I'm no engineer and am no electronics type person at all. I friend suggested I post my question here. I have a solar powered keyboard that uses an ML2032 3v lithium battery. I ordered a new one and received an LIR2032 3.6v battery. Will the higher…
Will
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