Questions tagged [low-battery]
The low-battery tag has no usage guidance.
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Why do batteries recover after a load is removed?
I carry a small 2-AA flashlight, and a few times, I have accidentally left it on in my holder. Each time it dies completely, so that no light is emitted, but if I turn it back off and wait for a few ...
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At what voltage is a NiMH battery empty?
I have a battery pack of NiMH batteries. It is ten cells with 1.2V, 4000mAh each, put together in series. So rated voltage is 12V. After charging, i.e. when the charging device says that it is ...
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Low battery level circuit - Changing "trigger" level
I am re-creating a simple low-battery level circuit that turns on a low-power LED to indicate that the battery needs to be changed. The circuit is shown below.
There are two things I would like to ...
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One battery slot kills its sitting battery
My kid has a battery-operated toy, it runs on three AAA batteries, connected in serial. Once, the toy suddenly stopped working, but all batteries were good. I decided to disassemble the toy and look ...
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Batteries and running time
If I have a system working at 2.5V-0.3mA powered by two CR123 3.7V-2000mAh.Is my system going to last the same time if I put my batteries in parallel or in series?Because if I want it to last 12hrs a ...
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A Lipo battery protection circuit
I would like to make a simple Li-Po protection circuit that will prevent a single-cell from going below 3.7V. My circuit needs to have a low current input detector (pref < 5uA.)
My attempt at this ...
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Low Battery Indicator
I'm looking to make a battery life indicator that I can use in conjunction with a micro-controller. I'm hoping that I can then read the current battery life remaining and increasingly put the micro-...
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If Li-Ion battery is deeply discharged, is it harmful for it to remain in this state unused?
It is well known that Li-Ion batteries should not be deep discharged.
But sometimes they do discharge deeply. Is it OK for the device to remain in such state for a long time (and recharge again only ...
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What's a good estimate on how low an alkaline battery voltage can be to still make the battery useful?
Here's a YT video by Duracell about how many batteries declared dead and sent to recycling still have some usable energy. In the beginning of the video there's a sequence where they have a row of ...
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how to build a low-voltage disconnect switch for DC 12.4V 70A?
How can I make a device that will make the power connected as long as the voltage of the power-supply keeps over 12.4 V (adjustable) and disconnect it if it falls below?
It also must connect the ...
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Best way to halve 12V battery voltage for 6V device, while still being able to measure the battery level?
I have a device that is powered by 4 AA (4x1.5V=6V) batteries, but I want to power it with a 12V battery.
The device measures its input voltage to determine the battery level. I only need to know if ...
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Low Battery Indicator for 2x AA Batteries
How would I create a circuit which turns on an LED when the voltage goes below 2.5V? I am using 2x AA batteries
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Why does this lithium battery have such a flat discharge curve?
I'm trying to understand some apparently anomalous observations of the discharge profile of a 1S lithium battery. I'm using this battery to run a Raspberry Pi Zero W, back-powering the Pi via the +5V ...
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Li-ion vs Li-Po batteries cut-off protection
I am confused with the differences between Li-ion batteries (like 18650) and Li-Po (the flat ones).
I know that basically they are both lithium ion, but when I want to buy I see that LiPos have always ...
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2xAAA battery => 3.3v/250mA step-up converter with logic-driven power control [superseded]
EDIT: The requirements in the question below appear to be practically unsolvable, but happily after a bit of digging I actually found an alternative equivalent RS232 device which runs off a 3.7V Li-Po ...
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