100,000,000 iPod owners and counting! A remarkable tribute to Apple’s iPod music player – no question! I wonder how many of these iPod owners know how their iPod battery works. Understandably most people don’t really care as long as it does. However I am interested and I’m sure there are others out there as well who want to know how their iPod battery actually delivers power to their iPod.
Most people would never realize how complex an iPod battery is nor would they realize how many components can be found within their iPod battery. For starters your iPod battery is made up of highly specialized battery components including:
- iPod battery connector
- iPod battery fuse
- iPod battery charge and discharge FETs
- iPod battery cell pack
- iPod battery sense resistor
- iPod battery primary and secondary protection ICs
- iPod battery fuel-gauge IC
- iPod battery thermistor
- iPod battery pc board
These components together allow your iPod battery to function so that you can listen to music while doing the various activities of your day. Before we can delve deep into each of these ipod battery components I want to make sure that we understand that these components together work in an effort to produce electrical current to supply to the iPod.
iPods require electrical power in order to function. iPods’ draw electrical current on demand from your iPod battery. However your iPod battery is not a storage house of electrical energy but instead your iPod battery is your iPod’s internal electrical “factory” that creates electrical energy through a process known as an electrochemical energy conversion and subsequently your iPod battery delivers electrical current to your iPod. The electrochemical energy conversion is a process of replenishing of electrons and it is this electron replenishment that causes the chemical conversion to take place and create the electrical energy byproduct. To understand electrochemical conversion let’s see how electricity is created in the first place.
Electricity is a property of subatomic particles which couples to electromagnetic fields and causes attractive and repulsive forces between them. This repulsive force between the subatomic particles creates an electric current; the flow of electric charge transports energy from one atom to another. Electrical current is measured in amperes, where 1 ampere is the flow of 62,000,000,000,000,000,000 electrons per second!
Inside your iPod battery engineers have designed a constant state of disequilibrium, which cause a continuous flow of electrons. When electrons move between the atoms (atoms are made up of particles called protons, neutrons, and electrons) a current or flow of electricity is created. But how is this current of electricity created to begin with? This comes back to our electrochemical conversion. In order to create electrical energy (or a constant state of disequilibrium, which cause a continuous flow of electrons) there must be an electrochemical system which includes the electrodes and the electrolyte housed within your battery. Electrons flow from one electrode to another and the electron flow is conducted by an electrolyte. In ipod batteries for example an electrochemical system can be comprised of the electrodes consisting of Carbon/Graphite for the negative electrode and Lithium cobaltite for the positive electrode. Between these electrodes is an electrolye which can be a highly conductive solution consisting of lithium hexafluorophosphate. The electrolyte solution is a chemical compound that when dissolved in a solvent (i.e. water) forms a solution that becomes an ionic conductor of electricity. Hence the electrochemical conversion!
Once the electrochemical conversion begins then the balance of the ipod battery’s specialized hardware components I mentioned above can be put to work transferring and monitoring the iPod battery and the iPod – all for the sole purpose of delivering power to your iPod.
Until next time, Dan Hagopian – www.batteryship.com
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