Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [battery-charging]

Please specify the battery type in your question. Include chemistry (e.g. lead-acid, Li-ion), voltage, capacity (in A·h or W·h), number of cells and how they are connected (series or parallel) .

References:

Lithium chemistries charging:

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Why are there 3 pins on some batteries?

Lots of new batteries (for mobile devices, MP3 players, etc) have connectors with 3 pins. I would like to know what is the purpose of this and how should I use these three pins? They are usually marked as (+) plus, (-) minus, and T.
adopilot
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How to measure capacity of a Lithium-ion battery

I bought a Lithium-ion battery for a camera (much cheaper than the brand replacement but non unreasonably cheap compared to AAA Li-Ion batteries with similar charge). I however have doubts that it has the capacity it claims on the package (in mAH).…
user12889
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Why charging Li-Ion batteries in cold temperatures would harm them?

Accordingly to what I've found in several sources (user's manual of electronic devices, various forums, e.t.c.) I shouldn't charge my Li-Ion batteries in cold temperatures because this would harm them. However it's completely unclear which kind of…
vdudouyt
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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 minutes, the light works weakly again. The…
Daniel
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How do USB charging and "smart" charging ports (e.g. Anker's PowerIQ) work?

Software engineer with a hobbyist understanding of EE here. I've noticed lately lots of claims from producers of USB battery packs that their ports are "smart" and "identify the device" to "deliver the maximum current for the device." A cursory look…
Kevin Wood
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Why are Alkaline, NiMH, and Li-ion AA measured differently (mAh, mWh, etc)?

Looking around Amazon, it seems that different types of batteries are measured differently: Does anyone know why? Li-ion are measured in mWh 1200mWh ALTIZURE (Cheap-Os) 3200mWh Deleepow 3000mWh AmpTorrent NiMH are measured in mAh 2000mAh…
coolaj86
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Measure Lithium ion battery voltage (thus remaining capacity)

What I am working with: I am running my self-made Arduino board (in the sense that I use the Arduino bootloader and code editor) at 3.3V, and powered from a Lithium ion battery, which is USB-charged by a corresponding Microchip charger IC. What I am…
boardbite
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Powering laptop from 12V sources without inverter

This question has two parts: 1) How inefficient is it to boost 12V to 120V and then back to 12V as in using a traditional car power inverter to power a laptop (i.e. the 12V car battery power is boosted to 120V by a power inverter and then back to…
Reed G. Law
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Can I disable a battery powered device by reversing half of its batteries?

When I have a device that is powered by two batteries, can I disable it by turning one battery around? For illustration, the purpose is to leave batteries in the device for storage, but it does not have an off switch. There are multiple solutions…
Volker Siegel
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Some advice on charging circuit used in simple UPS

I have looked around for some way of having a 5 volt power supply that acts like a UPS. Basically want to use a micro usb connector for +5 have a battery and li-ion or other charging circuit that will maintain uninterrupted power on the output. I…
Piotr Kula
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Lithium Battery Protection Circuit - Why are there two MOSFETs in series, reversed?

I was studying a battery protection chip and reference circuit (below) commonly used in cell phone Li-ion batteries, and am confused by the two MOSFETs in series on the negative terminal EB-. According to this question, I now understand that MOSFETs…
Ryan Griggs
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Can I safely trickle charge a 24v garage actuator battery with a pair of 12v solar panels?

I have a Hormann Promatic Akku Garage door actuator, since my garage doesn't have mains electricity. Generally speaking I'm very impressed with how well it works. Unfortunately while it lasts around two months between charging, it gives almost no…
Mark Booth
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How long does it take to recharge a car battery after starting?

Assuming a typical lead-acid, 12 V car battery (typically at 13 V or so fully charged), and that it takes roughly 500 A over 3 seconds to start an engine, how long will it take to recharge the battery at any given charge rate? Here's my attempt from…
Nick
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Why battery chargers take a pair of batteries and not one?

I have a number of AA- and AAA-sized NiMH rechargeable batteries ('accumulators'). All the chargers I encountered allow to charge 2 (4, 6, 8,..) such batteries at a time, but never a single battery. Is there a good engineering reason for this?
9000
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How fast can a Li-Ion battery be charged?

So far I've seen many Li-Ion battery chargers that do the full charge in about 1,5 hours or more. There're also NiMH battery chargers that claim they charge a NiMH battery in 15 minutes and then the manufacturer follows to say that it reduces the…
sharptooth
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