Battery questions

[sundance2013]

I need a little battery class. I'm not sure what some of the terms are and what the norms are for the batt.

First I think I need to get a charger that tells me how much juice I'm putting back into the battery. What are some good chargers
that will do this and are there any that will charge multiple batteries at once as well (2 or 3 at least)?

If my assumptions are correct from what I am seeing so far, with the Phantom I get about 2/3 usage of the capacity of the battery. Example, 2800mAH battery I get 1398 consumed mAH when the light flashes red. With my 3000mAH I get 1845mAH before the light flashes red. with the Phantom stock batter I get close to 50% usage, 1154mAH from the 2200mAH battery.

Does this sound right, normal?

OK terms, I know what rated capacity is but what does Charge capacity (Max Charge) and discharge rate (Max Discharge) relate to? What does the "3s" relate to?

Any good Android apps for keeping track of all this?

Thanks

 

[simonthk]

BAtteries are fairly simple. When you are using a charger and you choose how much AH ampere you are charging with, you are just choosing the speed of the charge. 3 ah faster than 1 ah.

There are some charger things on ebay that makes your normal charger charge like 6 batteries at once xt60. But it doesn't make it a faster charge, it just divides the charging ampere.

I am not sure what you mean by assumption of your weird battery testing The batteries are all the same voltage and the phantom only looks at what voltagte the battery delivers. Tus reaching low voltage will make your phantom blinking and tell you to land soon.
A higher MAH capacity battery will let you fly longer before the battery reaches a lower voltage.

When it comes to discharge, it is only important that it can discharge as fast as the motors can maximum use power. If the motors use a higher power (watt) than the battery can handle (lets say it has small wires, where little power can travel through) it will lower the voltage of the battery ouput, trying to force a higher ampere. But either way it will have the same power out. This can be fatal if not thought about in the right conditions. Meaning that a battery that still makes you fly, will not have the same power availble for the motors to handle quick movements or avoidance from tress or ground per say. This really sucks, because this can easily be the reason why you crash some day.

But that is why your assumption might be right. It is very difficult to say this exactly. It is all about when they reach the correct voltage for the blink to turn on.

The most important about batteries is, that you have them fully charged when you fly and that you never fly any longer time than they can easily handle. Get a voltage measure tool from ebay and check any battery before a flight. Also if the battery normally can handle 7 minutes of flight time, then be most athletic in the first 4 minutes, slow down the last 2 and land one minute before you really needs to. Both the batteries and the safety of the phantom will love this.

http://www.ebay.com/itm/DJI-Phantom-Bat ... 3a839df146
I am not aware of how great this charger works.

 

[simonthk]

Also I would like to know how you measure exactly how much power you have used from the batteries?

 

[sundance2013]

The assumption was comparing the OSD mAH consumed with the capacity rating of the battery. You gave me a lot of good information but it wasn't much help in answering my questions .

 

[Gizmo3000]

it's a lot of info to ingest.

-almost any battery charger you get will tell you how many may is being pumped back into a battery. (I think many use the same circuitry, as they all have the same digital readout), I have the Accucel6, as cheap as they come but loaded with features.

3s means it's a 3-cell battery/12volt system (tho it actually varies between 12.6 and 11volts ).

read up all all that stuff here
http://www.rchelicopterfun.com/rc-lipo-batteries.html