another thing to remember is all cell phones use lithium batteries just like laptops. so dont let them die. if u keep them above 50% charge... they will last much much longer.
for example, most cellular batteries are 3.7volts(thats how much a single pouch of a lithium battery produces, compared to alkaline.. 1.5 volts, and nickel.. 1.2) they are full voltage until they start to die.. they fall on their face!!
at 100% battery life they read 3.7 volts
at 75% battery life, they read 3.7 volts
at 50% battery life, they read 3.7 volts.
at 25% they read 3.69
when your battery says it is low... the voltage cut off turns your phone off. (this is why u can keep turning it on over and over and it shuts itself back down....)
if u let the battery droop down to 3 volts, you just damaged its TOTAL life and charge caspacity be 30%
if u let it reach 1 volt, it will hold a charge for 20 minutes maximum.
if u let it reach any lower than 1 volt, throw it away, it will never hold a charge again. the cathode got smacked... literally... the anode touched the cathode... they will never separate again.
lithium batteries are actually in a "pouch", the plastic around them is a case to protect it. if u expose a LI-Ion battery to oxygen, it will catch on fire!!! fun fun fun. it is very violent.. they actually sit there and burn like a sparkler until the battery reaches 0 volts
an alkaline battery loses power gradually. when they are full they make 1.5 volts,
at half dead, they made .75.
the problem with that, especially in cameras and such, is the camera needs at least 1 volt (for example) to take a picture... even though the battery still has half its life remaining.. the camera thinks it is dead. you can pull that battery out and use it in your tv remote for another 2 years.
alkaline only lose 1 to 2% of their battery life per month.... if u keep them refrigerated.... they only lose 1 to 2 % a YEAR!!! alkaline performs very poorly under high drain devices, like RC cars or cameras. it is very good in emergency equipment though because u can pick it up in a year when you need it and it will still have a charge
Nickel produce 1.2 volts, and lose power gradually, however they have much more current, so even though they produce less voltage than an alkaline.. their power is identical.
it really shines in a high power device pulling a lot of amperage, these will hold a charge much longer in a camera or RC car, 40% or more
now there are 2 types, Ni Cd and Ni Mh
NiCd has a memory effect. if u charge it when its only half dead... it remembers that... and will no longer hold anymore than half a charge
when you charge.. it produces tiny crystals in the paste of the cell... however if u keep charging at half capacity(think a cordless house phone for example, every night you oput it on the charger.. even though its not dead) the crystals build up in one spot... blocking off the rest of the battery. that is why when you put them in a battery tester, they still read 1.2 volts... even though they appear to be dead.
NiMh has no memory effect, so u can charge it whenever you want. the crystals push off of each other(electricity.. think magnetic..) preventing a blockage
heres a few tricks for anyone who has read this far...
if u need more voltage because ur about to get eaten by a lion and ur battery is dead... put it in your arm pit... heat the battery up,
heating the battery causes the chemical process to react faster... producing more voltage for a short time
to have a longer battery life on a single charge... charge it slower.. a house charger for example.
charging a battery is like building a ladder... the faster you charge it... the less steps you have to climb up... however, you also have less to climb down on..
the slower you charge it, the longer it will last.
the heavier the battery, the longer the life. literally. especially true with NiCd and NiMh
(when we raced RC cars, if we had a short 3 minute race.. we would charge them at 6 to 10 amps... (a 3 minute charge) and the 7.2 volt batteries would read as high as 10 volts, but by the time we got the battery in the car and on the track they were at 9 volts. for the first few laps we would have a very fast car, but it would lose its charge fast, by the final lap the battery would read 6 volts.
for long races we would have special batteries we charged over night... they only read 7.3 or 7.4 volts.. but we could do a 10 minute race and test the battery and they would still read 6 volts.)
dont charge your battery while discharging it. if u feel any heat, that is wasted electricity.. literally, that is how electricity dissipates.. through heat. youre hurting your batteries life.
i have a certificate in DC electronics(direct current... battery power) lol
im waiting on electric cars