# Laptop and cell phone batteries

1. Jul 22, 2008

### student85

How do these batteries work? Are they simply capacitors being connected in a parallel configuration?
What is the difference between a laptop and a cell phone battery?

2. Jul 22, 2008

### Integral

Staff Emeritus
Batteries are chemical devices. A battery contains different materials which react with a characteristic voltage. The ability to produce a current is determined by the amount of un-reacted materials present. When all (or most) of the material has undergone the reaction, no current can be produced..The battery is dead.

By applying a reverse voltage the direction of the reaction can be reversed, thus restoring the original composition and the ability to produce a current. The battery has been recharged.

3. Jul 22, 2008

### Staff: Mentor

Laptop and cell phone batteries are typically the same type of lithium ion battery.

4. Jul 22, 2008

### student85

Thanks guys.
So no capacitors involved?

5. Jul 22, 2008

### Integral

Staff Emeritus
No caps are used for energy storage. There will be some small ones in any an board circuitry associated with the battery.

6. Jul 23, 2008

### student85

Thanks Integral.
Btw, what is your profession? How do you guys know the answers to all problems??
I'm quite amazed by all the smart people on this site :P
I love this site :P

7. Jul 23, 2008

### Integral

Staff Emeritus
Answers to ALL questions. :rofl: That won't happen!

The mentors on this site have degrees in either science or Engineering. Mine are Physics and Math. For now, I am a Technican working in a wafer fab.

8. Jul 23, 2008

### Beasticly

Hey Integral,

I don't mean to barge in, but you seem to be quite knowledgable with batteries and the like so would you mind quickly poking over to my thread (https://www.physicsforums.com/showthread.php?t=246208) and telling me if I'm on the right track as far as batteries are concerned? Thanks! :)

9. Aug 9, 2011

### DrGeek

This might be the single best explanation of how cell phone batteries work that I have ever read. You concisely break down how they expend energy to power the phone, and you also explain how they are able to recharge in an easy-to-understand manner. Bravo to you!

Can you explain why lithium seems to be the core component of most modern batteries? What about the element allows it to store so much energy?

10. Aug 9, 2011

### Pengwuino

You may need to ask in a new thread as this may be in violation of our necroposting policy (this thread is 3 years old).

One thing you may also want to consider is that it's not always what is the best chemical or element for the job when it comes to things like these. You have to consider how much it costs to acquire the material, whether or not it's really usable in the environment it needs to be used in, etc.