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Questions tagged [batteries]

Devices to store chemical energy and convert it to electrical energy.

A battery is a device that stores chemical energy and releases it as electrical energy. Batteries are made up of one or more electrochemical cells that convert stored chemical energy into electrical energy. There are many different types of batteries, including disposable batteries (e.g., Alkaline, Zinc-Carbon) and rechargeable batteries (e.g., lithium-ion batteries used in cell phones, laptops, and cars).

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Why do we use capacitors and not batteries in defibrillator?

Why do we use capacitors in defibrillators and not batteries? I know that capacitors are used to store electrical energy but isn't the function of a battery just the same? Moreover, I know that batteries are used to make capacitors work in a…
musicinmyheart
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Does the mass of a battery change when charged/discharged?

If so, how much? Is it possible to detect it, or is it beyond any measurement? I'd say there are two possible scenarios (depending on the battery type) and both seem interesting: The battery reacts chemically with its environment. The battery…
Petr
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How do batteries lose capacity in winter?

One problem of electric vehicles is that the battery capacity often shrinks under low temperatures. Some batteries can lose as much as 50% of capacity in winter. What I don’t quite understand is how the capacity shrinks. Does the low temperature…
哲煜黄
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Why do 'dead' batteries work again after exchanging the places of the batteries in an electronic device?

My camera, which is powered by two AA batteries in series, would not power on. I removed the batteries, exchanged their locations, and the device worked again - for another 15 minutes or so. The temperature of the batteries did not change, and only…
David LeBauer
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Different batteries connected in parallel

If we have 2 batteries one of emf x and the other is of emf y and we connect them in series we get an effective emf of x+y. But what if we connect them in parallel, how to calculate the emf now?
Revo
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What happens when we connect a metal wire between the 2 poles of a battery?

As I remembered, at the 2 poles of a battery, positive or negative electric charges are gathered. So there'll be electric field existing inside the battery. This filed is neutralized by the chemical power of the battery so the electric charges will…
smwikipedia
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What is the difference between a battery and a charged capacitor?

What is the difference between a battery and a charged capacitor? I can see lot of similarities between capacitor and battery. In both these charges are separated and When not connected in a circuit both can have same Potential difference V. The…
claws
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Why can't batteries be charged quickly?

Charging of laptops, cell phones take so much time. Why can't we make such batteries easily/commercially which are charged more quickly? What's the thing behind this limiting?
biogirl
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Why doesn't the voltage increase when batteries are connected in parallel?

Can you please explain the thing below? When we add a battery in circuit then, it gives out some electric field that moves through the circuit and gives a force on electrons in conductor to produce current. When we connect two batteries parallel…
Predaking Askboss
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How can a battery charge up another battery to a higher percentage?

Say I have my phone on 5% and a large battery pack on 35% and I charge the phone. By the end the phone is on 100% and the pack is on 12%. How can the battery pack charge the phone up to a higher percentage of its current charge? I would expect that…
Giulio Crisanti
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Why does connecting a battery's positive terminal to the negative terminal of another battery not create a short circuit?

This is a question regarding the physics behind the observation. I have guessed the answer to the question, but I may be wrong, so I want to wait for the responses before posting it. Some major considerations: A battery's positive terminal does…
mehfoos
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What is Electromotive force (EMF)? How is it related to potential difference?

What is Electromotive force (EMF)? How is it related to the potential difference? Is it created by the potential difference in any conductor? Is it a process? Why is it called force? Does writing EMF instead of voltage make any difference in AC…
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At an atomic level, what happens when you connect two batteries in series so that their voltages are added?

I can't for the life of me figure this out. I feel like i'm missing some crucial detail about how batteries work. Imagine two batteries connected in series, like this: Circuit <= -(Battery A)+ <= -(Battery B)+ <= Circuit As far as I've studied,…
Lucas Cioffi
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Why aren't betavoltaics and alphavoltaics batteries widely used?

Betavoltaic batteries are devices which creates electricity from beta radiation of a radioactive material. Alphavoltaics operate similarly, using alpha radiation. The concept was invented roughly 50 years ago and they are safe enough to be used, for…
Suzan Cioc
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Theoretical physics for better batteries?

It is Earth day, so I started thinking about the theoretical physics problems that could help reduce greenhouse-gas emissions and fight climate change. We actually have a reasonable range of ways to generate energy without fossil fuels. The problem…
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