Understood, thank you and thank you all.
Have a nice day guys
What I'm going to write here may seem a little terse and rude, but I'm trying to get your ATTENTION! Please don't take it personally but this is your life and/or your family's life were talking about.
No, not 'understood' at all. I don't know if realise the implications of '4.4 - would be a problem.' A lipo burns a 2000F and shoots flames up to 6'. Anything within reach that is potentially combustable instantly combusts. That includes your face.
Back in the day lipos got a very bad reputation for causing fires, generally caused by crappy chargers. Lately, most fires are caused by overcharging, or trying to keep using damaged batteries.
How can i get to know the maximum amps of a battery?
The mere fact that you ask question says that you are not an engineer, and are therefore not qualified to 'know' (measure) the A of a battery.
The mAh of a battery is a shell game. It is essentially determined by how many potential -cycles- a battery will have.
The cycles are determined partly by how hard you draw the current, and how far down you run the voltage.
A lipo is fully charged at 4.2V. Notice though that when you buy one brand new it's at 3.65-3.75V. That's the nominal voltage, the 3.7 that's printed on the label. That's what the factory charges the battery to to give the longest life when sitting on a retail store shelf for a year or two.
When they say that 4.2 is the maximum, they mean that anything beyond that risks fire/explosion. (OK 4.25 or whatever but who wants to risk it.)
Beyond 4.2 the battery doesn't necessarily immediately go 'poof.' It starts to get warm, probably it puffs, the chemicals degrade, it gets hotter, there's a thermal runaway and -then- it goes poof. The only lipo fire I ever saw personally was a 'moderate impact' helicopter crash. walking over to it, and then looking for a bit, it had to be somewhere between 1 and 2 minutes before it actually caught fire, 3' flames. A multicell battery fire can -appear- to go out, then catch fire a minute later as another cell catches.
These numbers aren't cast in stone either. Manufacturers vary, chemistries vary, production processes vary. Stay on the *safe* side of all the numbers and you'll have the best chance of not suffering a disaster. But the reason I'm being LOUD about all this is that so far you're playing on ALL the UNSAFE sides of the numbers.
The point being that once you go past 4.2x, or give it a severe shock/impact, you're holding a grenade in your hand, the pin is pulled, you just haven't released the yet. But the the detonator is not under your -control-, it's a chemical reaction that will light up sooner or later.
...i just discharged a Lipo Battery completely (0v now)
BTW you just destroyed the lipo. Yes there're potentially ways to 'revive' them but it is severly damage, will have a drastically shortened lifespan, and every time you charge it you're playing 'pull the pin on the grenade and see if it lights up this time.'
Ok, so after a lipo battery charging, if the battery is low than 4.2V, this means that the battery is not fully charged right? So in other words, it will not overcharge if i keep charge it the same way over and over?
Not necessarily, and probably not, because you haven't mentioned what you're charging it with, also given some of the treatment you give them such as discharging down to 0V. A damaged battery -may- not have the ability to be fully recharged to 4.2. The fact that it won't go to 4.2 -may- be a sign of damage. A reputable charger, first, won't let a battery charge past 4.2, and if it doesn't reach 4.2 won't let it charge past a certain time limit.
The C rating of a battery is not cut and dried. Again, it is a shell game number picked by the manufacturer to get an 'OK' number of cycles from the battery by the average consumer. 100 cycles is generally assumed to the target cycles. (As was mentioned, manufacturers don't publish -real- specs.) You can, for instance, discharge a 10C battery at 20/30/40/whatever rate you want, but it may work only 20 or 5 times, or only once. OTOH I've heard of rare instances of mocel aircraft catching fire in flight because they pushed a battery too hard.
Battery usage isn't supposed to be measured by mA, it's supposed to be measured by V. The 'ABSOLUTE maximum discharge' is -generally- touted at 80% or about 3.4V. But, that will give you the fewest usable cycles. One fellow I read about, whose -job- it is to manage battery systems, said he got -600- cycles by dischargong to the nominal 3.7 / 50%.
Regardless the topic really was about charging. You didn't mention what size batteries you're using. Common consumer toys come with a charger, and shouldn't be messed with by either using a different charger or using the charger on other batteris unless you *KNOW* what you're doing. Here's a good reference about overcharging and the 4056.
http://www.rcgroups.com/forums/showpost.php?p=27249411&postcount=334One more BTW. NEVER leave a charger unattended. There was a story this past Xmas about a new toy, got used a few times in the morning, and was left on the charger while the family went out. They came home and the house was burned down. It was -probably- a 10-15 minute charger, that -probably- had a warning label on it that said 'do NOT leave on charge for more than one hour.' Misuse = 'poof.' Junky charger = 'poof'